[Federal Register Volume 85, Number 169 (Monday, August 31, 2020)]
[Proposed Rules]
[Pages 54178-54232]
[FR Doc No: 2020-17730]

Vol. 85

Monday,

No. 169

August 31, 2020

Part VI

Environmental Protection Agency

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40 CFR Part 60

Standards of Performance for New Stationary Sources and Emission
Guidelines for Existing Sources: Other Solid Waste Incineration Units
Review; Proposed Rule

Federal Register / Vol. 85, No. 169 / Monday, August 31, 2020 /
Proposed Rules

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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 60

[EPA-HQ-OAR-2003-0156; FRL-10013-19-OAR]
RIN 2060-AU60

Standards of Performance for New Stationary Sources and Emission
Guidelines for Existing Sources: Other Solid Waste Incineration Units
Review

AGENCY: Environmental Protection Agency (EPA).

ACTION: Proposed rule.

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SUMMARY: In accordance with requirements under the Clean Air Act (CAA),
the U.S. Environmental Protection Agency (EPA) performed a periodic
review of the emissions standards and other requirements for Other
Solid Waste Incineration (OSWI) units, covering certain very small
municipal waste combustion (VSMWC) and institutional waste incineration
(IWI) units. Although the EPA is not proposing revisions to the OSWI
New Source Performance Standards (NSPS) and Emission Guidelines (EG)
specifically based on its statutory periodic review, the EPA is
otherwise--in accordance with its authority under the CAA--proposing
changes to the OSWI NSPS and EG.

DATES: Comments. Comments must be received on or before October 15,
2020. Under the Paperwork Reduction Act (PRA), comments on the
information collection provisions are best assured of consideration if
the Office of Management and Budget (OMB) receives a copy of your
comments on or before September 30, 2020.
    Public hearing. If anyone contacts us requesting a public hearing
on or before September 8, 2020, the EPA will hold a virtual public
hearing. Please refer to the SUPPLEMENTARY INFORMATION section for
additional information on requesting and registering for a public
hearing.

ADDRESSES: You may send comments, identified by Docket ID No. EPA-HQ-
OAR-2003-0156, 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-2003-0156 in the subject line of the message.
     Fax:<PHONE_NUMBER>. Attention Docket ID No. EPA-HQ-OAR-
2003-0156.
     Mail: U.S. Environmental Protection Agency, EPA Docket
Center, Docket ID No. EPA-HQ-OAR-2003-0156, Mail Code 28221T, 1200
Pennsylvania Avenue NW, Washington, DC 20460.
     Hand Delivery or Courier (by scheduled appointment only):
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).
    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 are closed to the public, with limited exceptions, to
reduce the risk of transmitting coronavirus disease 2019 (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 may
be a delay in processing mail and faxes. Hand deliveries and couriers
may be received by scheduled appointment only. For further information
on EPA Docket Center services and the current status, please visit us
online at https://www.epa.gov/dockets. Refer to the SUPPLEMENTARY
INFORMATION section below for additional information.

FOR FURTHER INFORMATION CONTACT: For questions about this proposed
action, contact Dr. Nabanita Modak Fischer, Sector Policies and
Programs Division (E143-05), Office of Air Quality Planning and
Standards, U.S. Environmental Protection Agency, Research Triangle
Park, North Carolina 27711; telephone number:<PHONE_NUMBER>; fax
number:<PHONE_NUMBER>; and email address<EMAIL_ADDRESS>
SUPPLEMENTARY INFORMATION:
    Participation in virtual public hearing. Please note that the EPA
is deviating from its typical approach because the President has
declared a national emergency. Due to the current Centers for Disease
Control and Prevention (CDC) recommendations, as well as state and
local orders for social distancing to limit the spread of COVID-19, the
EPA cannot hold in-person public meetings at this time.
    If requested, the virtual public hearing will be held on September
15, 2020. The hearing will convene at 9:00 a.m. Eastern Time (ET) and
will conclude at 5:00 p.m. ET. The EPA may close a session 15 minutes
after the last pre-registered speaker has testified if there are no
additional speakers. The EPA will announce further details on the
virtual public hearing at https://www.epa.gov/stationary-sources-air-pollution/other-solid-waste-incinerators-oswi-new-source-performance.
    The EPA will begin pre-registering speakers for the hearing upon
publication of this document in the Federal Register. To register to
speak at the virtual hearing, please use the online registration form
available at https://www.epa.gov/stationary-sources-air-pollution/other-solid-waste-incinerators-oswi-new-source-performance or contact
Ms. Virginia Hunt at<PHONE_NUMBER> or by email at
<EMAIL_ADDRESS>The last day to pre-register to speak at the
hearing will be September 14, 2020. Prior to the hearing, the EPA will
post a general agenda that will list pre-registered speakers in
approximate order at: https://www.epa.gov/stationary-sources-air-pollution/other-solid-waste-incinerators-oswi-new-source-performance.
    The EPA will make every effort to follow the schedule as closely as
possible on the day of the hearing; however, please plan for the
hearing to run either ahead of schedule or behind schedule.
    Each commenter will have 5 minutes to provide oral testimony. The
EPA encourages commenters to provide the EPA with a copy of their oral
testimony electronically (via email) by emailing it to Dr. Nabanita
Modak Fischer and Ms. Virginia Hunt. The EPA also recommends submitting
the text of your oral testimony as written comments to the rulemaking
docket.
    The EPA may ask clarifying questions during the oral presentations
but will not respond to the presentations at that time. Written
statements and supporting information submitted during the comment
period will be considered with the same weight as oral testimony and
supporting information presented at the public hearing.
    Please note that any updates made to any aspect of the hearing will
be posted online at https://www.epa.gov/stationary-sources-air-pollution/other-solid-waste-incinerators-oswi-new-source-performance.
While the EPA expects the hearing to go forward, if requested, as
described in this preamble, please monitor our website or

contact Ms. Virginia Hunt at<PHONE_NUMBER> or<EMAIL_ADDRESS>to
determine if there are any updates. The EPA does not intend to publish
a document in the Federal Register announcing updates.
    If you require the services of a translator or a special
accommodation such as audio description, please pre-register for the
hearing with Ms. Virginia Hunt and describe your needs by September 8,
2020. The EPA may not be able to arrange accommodations without advance
notice.
    Docket. The EPA has established a docket for this rulemaking under
Docket ID No. EPA-HQ-OAR-2003-0156. All documents in the docket are
listed on the Regulations.gov website. 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 and will be publicly available only in hard
copy. Publicly available docket materials are available electronically
through https://www.regulations.gov/.
    Instructions. Direct your comments to Docket ID No. EPA-HQ-OAR-
2003-0156. 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 electronically any information that you consider
to be CBI or other information whose disclosure is restricted by
statute. 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.
    The EPA is temporarily suspending its Docket Center and Reading
Room for public visitors, with limited exceptions, to reduce the risks
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/ as there may be a delay in processing mail and
faxes. Hand deliveries or couriers will be received by scheduled
appointment only. 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 CDC, local area health departments, and our federal partners
so that we can respond rapidly as conditions change regarding COVID-19.
    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-2003-0156. Note that
written comments containing CBI and submitted by mail may be delayed
and no hand deliveries will be accepted.
    Preamble acronyms and abbreviations. 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
identifies the following terms and acronyms here:

ACI air curtain incinerator
ANSI American National Standards Institute
AOGA Alaska Oil and Gas Association
ASME American Society of Mechanical Engineers
Cd cadmium
CAA Clean Air Act
CBI Confidential Business Information
CDC Centers for Disease Control and Prevention
CDX Central Data Exchange
CEDRI Compliance and Emissions Data Reporting Interface
CEMS continuous emissions monitoring systems
CFR Code of Federal Regulations
CISWI commercial and industrial solid waste incineration
CO carbon monoxide
COVID-19 coronavirus disease 2019
D.C. Circuit U.S. Court of Appeals for the District of Columbia
Circuit
DCOT digital camera opacity technique
DF dioxins/furans
ECHO Enforcement and Compliance History Online
EG emission guidelines
EPA Environmental Protection Agency
ERT Electronic Reporting Tool
ET Eastern Time
FVF fuel variability factor
HCl hydrochloric acid
Hg mercury
HMIWI hospital, medical, and infectious waste incineration
ICR Information Collection Request
IWI institutional waste incineration
MACT maximum achievable control technology
MSW municipal solid waste
MWC municipal waste combustor
NEI National Emissions Inventory
ng/dscm nanograms per dry standard cubic meter

N nitrogen
NOX oxides of nitrogen
NRDC Natural Resources Defense Council
NSPS new source performance standards
NTTAA National Technology Transfer and Advancement Act
OSWI other solid waste incineration
Pb lead
PM particulate matter
ppmvd parts per million by dry volume
PRA Paperwork Reduction Action
RFA Regulatory Flexibility Act
SO2 sulfur dioxide
SRI small remote incinerator
SSM startup, shutdown, and malfunction
TEQ toxic equivalency factor
TMB total mass basis
TPD tons per day
[micro]g/dscm micrograms per dry standard cubic meter
UMRA Unfunded Mandates Reform Act
VCS voluntary consensus standards
VSMWC very small municipal waste combustion
XML extensible markup language

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

I. General Information
    A. Does this action apply to me?
    B. What is the background?
    C. What action is the Agency taking?
    D. What is the Agency's authority for taking this action?
    E. What data collection activities were conducted?
    F. What other relevant background information and data are
available?
    G. What are the incremental costs and benefits of this action?
II. OSWI Review and Proposed Revisions
    A. CAA Section 129(a)(5) Review
    B. What other actions are we proposing?
    C. What compliance dates are we proposing?
III. Summary of Cost, Environmental, and Economic Impacts
    A. What are the affected sources?
    B. What are the air quality impacts?
    C. What are the cost impacts?
    D. What are the economic impacts?
    E. What are the benefits?
IV. Request for Comments
V. Statutory and Executive Orders 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. General Information

A. Does this action apply to me?

    Categories and entities potentially affected by the proposed action
are those that operate OSWI units. The NSPS and EG for OSWI,
hereinafter referred to as ``the OSWI standards,'' affect the
categories of sources identifed in Table 1 of this preamble:

 Table 1--Industrial Source Categories Affected by This Proposed Action
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                                                        Examples of
        Source category           NAICS code \1\   potentially regulated
                                                          entities
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Any state, local, or tribal     562213, 92411....  Solid waste
 government using a VSMWC unit.                     combustion units
                                                    burning municipal
                                                    solid waste (MSW).
Any correctional institutions   922 7213.........  Correctional
 using an IWI unit.                                 institutions.
Any nursing or residential      623..............  Any nursing care,
 care facilities using an OSWI                      residential
 unit.                                              intellectual and
                                                    developmental
                                                    disability,
                                                    residential mental
                                                    health and substance
                                                    abuse, or assisted
                                                    living facilities.
Any federal government agency   928, 7121........  Department of Defense
 using an OSWI unit.                                (labs, military
                                                    bases, munition
                                                    facilities) and
                                                    National Parks.
Any educational institution     6111, 6112, 6113.  Primary and secondary
 using an OSWI unit.                                schools,
                                                    universities,
                                                    colleges, and
                                                    community colleges.
Any church or convent using an  8131.............  Churches and
 OSWI unit.                                         convents.
Any civic or religious          8134.............  Civic associations
 organization using an OSWI                         and fraternal
 unit.                                              associations.
Any industrial or commercial    114, 211, 212,     Oil and gas
 facility using a VSMWC unit.    221, 486.          exploration
                                                    operations; mining;
                                                    pipeline operators;
                                                    utility providers;
                                                    fishing operations.
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\1\ North American Industry Classification System.

    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 the 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 action, you should carefully
examine the applicability criteria found in 40 CFR 60.2885, 60.2981,
and 60.2991. 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.

B. What is the background?

    Section 129 of the CAA requires the EPA to develop and adopt NSPS
and EG for solid waste incineration units in accordance with CAA
sections 129 and 111. Section 129(a) of the CAA requires the EPA to
establish NSPS for new sources, and CAA section 129(b) requires the EPA
to establish procedures for states to submit plans for implementing EG
for existing sources (and see CAA sections 111(b) and (d)). The EPA
proposed NSPS and EG for OSWI units on December 9, 2004, and
promulgated them on December 16, 2005 (70 FR 74870), at 40 CFR part 60,
subparts EEEE and FFFF.\1\ Following that final action, the
Administrator received a petition for reconsideration of the OSWI
standards, and on June 28, 2006, the EPA announced reconsideration on
the final OSWI rules (71 FR 36726). After consideration of comments and
information received through the reconsideration process, we concluded
that no additional changes were necessary to the final OSWI rules (72
FR 2620, January 22, 2007).
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    \1\ The regulations were revised on November 24, 2006 (71 FR
67802) in a direct final rule to address corrections.
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    In addition to the administrative reconsideration requests, some
entities petitioned for judicial review of the 2005 OSWI standards. The
judicial

review proceedings initially were stayed and, ultimately, the EPA
requested a voluntary remand of the OSWI standards. By Order dated
April 21, 2016, the U.S. Court of Appeals for the District of Columbia
Circuit (the D.C. Circuit) granted the EPA's request for a remand.
Sierra Club v. EPA, No. 06-1066. The remand was requested to allow the
EPA to consider potential revisions, if any, to the OSWI standards that
might be appropriate in light of certain legal developments, including
2007 and 2008 decisions from the D.C. Circuit.
    The OSWI standards establish maximum achievable control technology
(MACT) emission limits for OSWI units. Under current regulations, the
term ``OSWI unit'' means either a VSMWC unit or an IWI unit. A VSMWC
unit is any municipal waste combustion unit that has the capacity to
combust less than 35 tons per day (TPD) of MSW or refuse-derived fuel.
An IWI unit is any combustion unit that combusts institutional waste
and is a distinct operating unit of the institutional facility that
generated the waste. The OSWI standards set emission standards for nine
pollutants: Cadmium (Cd), carbon monoxide (CO), dioxins/furans (DF),
hydrochloric acid (HCl), lead (Pb), mercury (Hg), oxides of nitrogen
(NOX), particulate matter (PM), and sulfur dioxide
(SO2) and also establish opacity standards.
    CAA section 129(a)(5) requires the EPA, every 5 years, to review
and, in accordance with CAA sections 129 and 111, revise standards and
other requirements for solid waste incineration units (such as the OSWI
standards). In 2018, the U.S. District Court for the District of
Columbia found that the EPA had failed to undertake the requisite CAA
section 129(a)(5) periodic review of the OSWI standards and ordered the
EPA to do the review; publish a proposed rulemaking by August 31, 2020;
and promulgate a final rule by May 31, 2021. Sierra Club v. Wheeler,
330 F.Supp.3d 407.

C. What action is the Agency taking?

    The EPA has conducted the requisite CAA section 129(a)(5) 5-year
review, and we are giving notice of that review. We are not proposing
any revisions to the OSWI standards specifically based on that review,
but we are proposing various changes to the OSWI standards, including
some changes that were occasioned by the 2016 voluntary remand of the
OSWI standards (and the legal developments related to that request for
a remand). In accordance with the EPA's general authority under CAA
section 129(a) and and as discussed further in sections II.A and II.B
of this preamble, we are proposing: (1) Certain MACT floor
redeterminations; (2) changes to applicability provisions; (3) testing
and monitoring flexibilities so that units with rudimentary designs can
demonstrate compliance with the rule; (4) revised regulatory provisions
related to emissions during periods of startup, shutdown, and
malfunction (SSM); (5) provisions for electronic reporting of certain
notifications and reports; (6) revisions to recordkeeping and reporting
provisions consistent with the revised testing and monitoring; (7)
changes to title V permitting requirements; and (8) other technical
edits, clarifications, and revisions intended to improve the
understanding of the rule and improve consistency with other CAA
section 129 rules.

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

    Section 129 of the CAA requires the EPA to establish NSPS and EG
pursuant to sections 111 and 129 of the CAA for new and existing solid
waste incineration units, including ``other categories of solid waste
incineration units.'' This action amends the OSWI standards under such
authority. In addition, CAA section 129(a)(5) specifically requires the
EPA to periodically review and revise the standards and the
requirements for solid waste incineration units, including OSWI units.
    The EPA has substantial discretion to distinguish among classes,
types, and sizes of incinerator units within a category while setting
standards. CAA section 129(a)(2) provides that standards ``applicable
to solid waste incineration units promulgated under . . . [section 111]
and this section shall reflect the maximum degree of reduction in
emissions of . . . [certain listed air pollutants] that the
Administrator, taking into consideration the cost of achieving such
emission reduction and any non-air quality health and environmental
impacts and energy requirements, determines is achievable for new and
existing units in each category.'' This level of control is referred to
as a maximum achievable control technology, or MACT standard. CAA
section 129(a)(4) further directs the EPA to set numeric emission
limits for certain enumerated pollutants (Cd, CO, DF, HCl, Pb, Hg,
NOX, PM, and SO2). In addition, the standards
``shall be based on methods and technologies for removal or destruction
of pollutants.'' CAA section 129(a)(3).
    In promulgating a MACT standard, the EPA must first calculate the
minimum stringency levels for new and existing solid waste incineration
units in a category, generally based on levels of emissions control
achieved in practice by the subject units. The minimum level of
stringency is called the MACT ``floor,'' and there are different
approaches to determining the floors for new and/or existing sources.
For new (and reconstructed sources), CAA section 129(a)(2) provides
that the ``degree of reduction in emissions that is deemed achievable .
. . shall not be less stringent than the emissions control that is
achieved in practice by the best controlled similar unit, as determined
by the Administrator.'' Emissions standards for existing units may be
less stringent than standards for new units, but CAA section 129(a)(2)
requires that the standards ``shall not be less stringent than the
average emissions limitation achieved by the best performing 12 percent
of units in the category.'' The MACT floors form the least stringent
regulatory option the EPA may consider in the determination of MACT
standards for a source category. The EPA must also determine whether to
control emissions ``beyond-the-floor,'' after considering the costs,
non-air quality health and environmental impacts, and energy
requirements of such more stringent control.
    In general, all MACT analyses involve an assessment of the
emissions from the best performing units in a source category. The
assessment can be based on actual emissions data, knowledge of the air
pollution control in place in combination with actual emissions data,
or on other information, such as state regulatory requirements, that
enables the EPA to estimate the actual performance of the regulated
units. For each source category, the assessment involves a review of
actual emissions data with an appropriate accounting for emissions
variability. Other methods of estimating emissions can be used provided
that the methods can be shown to provide reasonable estimates of the
actual emissions performance of a source or sources. Where there is
more than one method or technology to control emissions, the analysis
may result in several potential regulations (called regulatory
options), one of which is selected as MACT for each pollutant. Each
regulatory option the EPA considers must be at least as stringent as
the minimum stringency ``floor'' requirements. The EPA must examine,
but is not necessarily required to adopt, more stringent ``beyond-the-
floor'' regulatory options to determine MACT. Unlike the floor minimum
stringency requirements, the EPA must consider

various impacts of the more stringent regulatory options in determining
whether MACT standards are to reflect ``beyond-the-floor''
requirements. If the EPA concludes that the more stringent regulatory
options have unreasonable impacts, the EPA selects the ``floor-based''
regulatory option as MACT. If the EPA concludes that impacts associated
with ``beyond-the-floor'' levels of control are acceptable in light of
additional emissions reductions achieved, the EPA selects those levels
as MACT.
    Under CAA section 129(a)(2), for new sources, the EPA determines
the best control currently in use for a given pollutant and establishes
one potential regulatory option at the emission level achieved by that
control with an appropriate accounting for emissions variability. More
stringent potential beyond-the-floor regulatory options might reflect
controls used on other sources that could be applied to the source
category in question.
    For existing sources, the EPA determines the average emissions
limitation achieved by the best performing 12 percent of units to form
the floor regulatory option. More stringent beyond-the-floor regulatory
options reflect other or additional controls capable of achieving
better performance.
    As noted above, CAA section 129(a)(5) requires the EPA to conduct a
review of the standards at 5-year intervals and, in accordance with CAA
sections 129 and 111, revise the standards. In conducting periodic
reviews under CAA section 129(a)(5), the EPA attempts to assess the
performance of and variability associated with control measures
affecting emissions performance at sources in the subject source
category (including the installed emissions control equipment), along
with recent developments in practices, processes, and control
technologies, and determines whether it is appropriate to revise the
NSPS and EG. This approach is consistent with the requirement that
standards under CAA section 129(a)(3) ``shall be based on methods and
technologies for removal or destruction of pollutants before, during or
after combustion.'' We do not interpret CAA section 129(a)(5), together
with CAA section 111, as requiring the EPA to recalculate MACT floors
in connection with this periodic review.\2\ This general approach is
similar to the approach taken by the EPA in periodically reviewing CAA
section 111 standards, which, under CAA section 111(b)(1)(B), requires
the EPA, except in specified circumstances, to review NSPS promulgated
under that section every 8 years and to revise the standards if the EPA
determines that it is appropriate to do so.
---------------------------------------------------------------------------

    \2\ Elsewhere in the CAA, including under CAA section 112(d)(6),
the EPA is also obliged to undertake periodic reviews. Although the
nature or scope of the periodic review under CAA section 112(d)(6)
is different than under CAA section 129(a)(5), it may be worth
noting that, even under CAA section 112(d)(6), the EPA is not
obligated to recalculate MACT floors in the course of a periodic
review. NRDC v. EPA, 529 F.3d 1077, 1084 (D.C. Cir. 2008); Nat'l
Ass'n for Surface Finishing v. EPA, 795 F.3d 1, 7-9 (D.C. Cir.
2015).
---------------------------------------------------------------------------

E. What data collection activities were conducted?

    The EPA reviewed the inventory of OSWI units developed for the
current standards and performed data gathering to identify additional
units.\3\ The current OSWI rule covers VSMWC and IWI as well as air
curtain incinerators (ACIs) combusting municipal solid waste or
institutional waste. ACIs burning only wood waste, clean lumber, and
yard waste are only subject to opacity requirements in the OSWI rule.
The EPA identified 97 VSMWC, IWI, and ACI units at 84 facilities from
the prior inventory. Data searches to identify additional units
encompassed review of the existing EPA databases, state permit
databases, manufacturers' websites, other government agencies, and
military and police sources.
---------------------------------------------------------------------------

    \3\ An OSWI inventory was developed for the 2005 rulemaking and
included in Docket ID No. EPA-HQ-OAR-2003-0156.
---------------------------------------------------------------------------

    The EPA's Enforcement and Compliance History Online (ECHO) website
allows users to search for facilities by NSPS subparts.\4\ The ECHO
database provides integrated compliance and enforcement information for
approximately 800,000 regulated facilities nationwide. For facilities
identified by ECHO as subject to the OSWI NSPS, the EPA conducted web
searches and reviewed online state air permits, where available. The
EPA added 20 units at 20 facilities to the OSWI inventory from the ECHO
search results. No emissions data were found for these units.
---------------------------------------------------------------------------

    \4\ See https://echo.epa.gov/.
---------------------------------------------------------------------------

    The EPA also searched the 2014 National Emissions Inventory (NEI),
Version 2, to identify facilities with OSWI units. The NEI is a
database that contains information about sources that emit certain air
pollutants, known as ``criteria'' pollutants, their precursors, and
hazardous air pollutants. The database includes estimates of annual air
pollutant emissions from sources in the 50 states, the District of
Columbia, Puerto Rico, and the U.S. Virgin Islands. The EPA collects
this information and releases an updated version of the NEI database
every 3 years. The NEI also includes information about control devices
and control approaches. Based on the NEI, four units at four facilities
were added to the EPA's inventory of OSWI sources. Emissions data are
available for only three of these units; no emissions data were found
for the remaining unit.
    The EPA searched state permit databases and reviewed online
permits, including title V and general permits, to identify additional
OSWI units. Fourteen additional units at 14 facilities were identified
and added to the OSWI inventory as a result of the permit reviews. No
emissions data were found for these units in the permit documents;
however, Pima County Department of Environmental Quality (PDEQ)
provided a recent test report from 2019 for one unit in Arizona.
    The EPA reviewed customer lists available on two incinerator
manufacturer websites. These incinerators are small, portable
incinerators, and the customer lists included universities and other
entities. Ten units at 10 facilities were added to the OSWI inventory
from incinerator manufacturer customer lists. Other searches included
the EPA's WebFIRE database, the U.S. Drug Enforcement Administration
website, the National Park Service website, the EPA's Toxics Release
Inventory, and the California Air Resources Board and Air Quality
Maintenance Districts websites. No units were added to the OSWI
inventory from these data sources.
    In addition to the OSWI units identified through the data searches
described above, we also considered and included 29 remote incinerators
at 25 facilities and associated emissions test and waste information
collected from commercial and industrial facilities in Alaska (as
further discussed in section II.B of this preamble). Taking these all
together, a total of 174 OSWI units at 157 facilities were identified.
These searches are documented in the memorandum, Documentation of Data
Gathering Efforts for Other Solid Waste Incineration (OSWI) Units,
which is available in the docket for this action.

F. What other relevant background information and data are available?

    In addition to inventorying OSWI units, the EPA reviewed the ECHO
and the NEI information, as well as state permit databases, for
representative emissions data for OSWI units. In state permit
databases, we obtained limited information for two OSWI units, both
with capacities greater than 10 TPD (but

less than 35 TPD), one located at a Texas facility and the other at an
Arizona facility. The information for the Texas facility included an
emissions test report for the nine OSWI pollutants for one OSWI unit,
and the information for the Arizona facility included a test summary
for one OSWI unit. The EPA also obtained limited emissions data (for
the nine pollutants) from the 2014 NEI, Version 2 for three of the four
OSWI units identified in the NEI. The NEI data did not include control
device information for these four units. We also reviewed data
collected during the development of the NSPS and EG for Commercial and
Industrial Solid Waste Incineration (CISWI) units,\5\ as well as
additional test data submitted by the Alaska Oil and Gas Association
(AOGA) for small remote incinerators (SRI) in Alaska (submitted in
connection with a request that the EPA modify the SRI emission limits
established in the February 7, 2013, final CISWI rule).\6\
---------------------------------------------------------------------------

    \5\ Includes emissions data collected from Phase II of the CISWI
ICR survey used to support the March 21, 2011 CISWI final rule (76
FR 15704) as well as the 2013 CISWI final reconsideration (78 FR
9112, February 7, 2013).
    \6\ As further discussed in sections II.B.1 and II.B.2 of this
preamble, the EPA has re-evaluated the applicability of the CISWI
rules to certain incinerators burning more than 30-percent MSW and
is also proposing to revise the OSWI rules such that the OSWI
standards will be applicable to these incinerators, which would be
treated as VSMWC units.
---------------------------------------------------------------------------

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

    We have estimated that this proposed rule will decrease burden by
$57,000 annually. We anticipate about 31 tons per year in emission
reductions in the CAA section 129 pollutants as a result of the
proposed amendments. See section III of this preamble for additional
information.

II. OSWI Review and Proposed Revisions

A. CAA Section 129(a)(5) Review

1. How did the EPA conduct the review under CAA section 129(a)(5)?
    In conducting periodic reviews under CAA section 129(a)(5), the EPA
attempts to assess the performance of and variability associated with
control measures affecting emissions performance at sources in the
subject source category (including the installed emissions control
equipment), along with developments in practices, processes, and
control technologies. For development of the proposed rule, the EPA
reviewed available performance data for currently operating OSWI units
or the best representative sources. In reviewing the standards based on
currently available emissions information, we address the CAA section
129(a)(5) review's goals of assessing the performance efficiency of the
installed equipment and ensuring that the emission limits reflect the
performance of the technologies required by the MACT standards. In
addition, we considered whether new technologies and processes and
improvements in practices have been demonstrated at sources subject to
the 2005 OSWI rule.
    Our review focused on identifying OSWI units to develop an
inventory of units and evaluating developments in processes and control
technologies that have occurred since the OSWI standards were
promulgated. Where we identified additional units or new developments
at units, we analyzed their emissions and controls and the technical
feasibility, estimated costs, energy implications, and non-air
environmental impacts of any identified controls. We also considered
emission reductions associated with applying each development, if any.
This analysis informed our decision of whether to revise the OSWI
emissions standards. In addition, we considered the appropriateness of
applying controls to new sources versus retrofitting existing sources.
For these purposes, we considered any of the following to be a
development:
     Any add-on control technology or other equipment that was
not identified and considered during development of the original
standards;
     any improvements in previously identified and considered
add-on control technology or other equipment that could result in
additional emissions reduction;
     any process change or pollution prevention alternative
that could be broadly applied to the industry and that was not
identified or considered during development of the original standards;
and
     any significant changes in the cost (including cost
effectiveness) of applying controls (including controls the EPA
considered during the development of the original standards).
    In addition to reviewing the processes and control technologies
that were considered at the time we originally developed the OSWI
standards, we reviewed, as discussed in sections I.E and I.F of this
preamble, a variety of data sources in our investigation of potential
processes or controls to consider.
2. Results and Proposed Actions From the EPA's CAA Section 129(a)(5)
Review
    We identified limited emissions data for three out of four OSWI
units from the NEI, and emissions test data for two new large OSWI
units from state permit documentation that demonstrate compliance with
the OSWI standards through use of add-on control devices similar to
those considered during the original OSWI rule development. From the
limited data available, we did not identify any new developments in
practices, processes, or control technologies for any OSWI units. Based
strictly on our 5-year review analysis, we do not believe that any
changes to the OSWI standards are appropriate, and, accordingly, the
EPA is not proposing any revisions pursuant to CAA section 129(a)(5).

B. What other actions are we proposing?

    Although not predicated on the CAA section 129(a)(5) review, the
EPA is taking the opportunity to propose certain changes to the OSWI
standards in light of other developments and our experience with the
CAA section 129 solid waste incinerator rules, as well as
considerations associated with the 2016 remand of the 2005 OSWI
standards. Thus, we are proposing changes to OSWI sub-categories and
related MACT floor recalculations. Additionally, we are proposing other
applicability-related and definitional changes. These proposed
revisions are discussed in sections II.B.1 and II.B.2 of this preamble.
We are also proposing changes to the SSM provisions; the testing,
monitoring, recordkeeping, and reporting requirements; the
applicability of title V permitting for certain ACIs; and miscellaneous
other technical and editorial changes to the regulatory text. These
proposed changes are discussed in sections II.B.3 through II.B.8 of
this preamble.
1. Proposed Revisions to the MACT Floor
    We are proposing MACT floor recalculations for the OSWI source
category in light of the 2016 voluntary remand of judicial proceedings
relating to the OSWI standards, as well as public comments regarding
the final OSWI standards (70 FR 74870, December 16, 2005) that raised
issues that, upon further consideration, we believe should be
readdressed. At the time the EPA set the OSWI standards, we lacked
emissions data on OSWI units, and the emission limits were based on
information for similar sources in the hospital, medical, and
infectious waste incineration (HMIWI) unit source

category, considering the similarities in combustion unit size, design,
operations, and waste composition between OSWI and HMIWI units.\7\ We
have now collected additional information on two new OSWI units
(constructed after the OSWI standards were issued) and emissions
information for certain existing small incineration units located in
Alaska that previously have been regarded as CISWI units, as small
remote incinerators (SRI), but--under this proposal--are treated as
OSWI units.\8\ We are proposing to consider the existing SRI units as
VSMWC units subject to the OSWI standards. In light of the voluntary
remand and the additional data gathered, we are proposing revised
subcategories and MACT standards that better reflect actual emissions
test data from OSWI units and the population of OSWI. These standards
are based, in part, on the size of the OSWI unit. The proposed
standards are more representative of and better reflect the emissions
achievable for new and existing units in each category required under
CAA sections 129(a)(2) and (4).
---------------------------------------------------------------------------

    \7\ The 2005 MACT standards were developed based on the best
representative sources. For new IWI and VSMWC units, the MACT floor
emission limits were based on emissions information from HMIWIs
similar in size, design, and operation and using medium-efficiency
wet scrubbers for emissions control. For existing IWI and VSMWC
units, the EPA considered the MACT floor based on emissions test
information from small, uncontrolled, modular/starved air municipal
waste combustion (MWC) units that were collected during the MWC
regulatory development process. However, the EPA had also identified
one existing OSWI unit, an IWI unit, with a medium efficiency wet
scrubber. Therefore, the EPA ultimately set beyond-the-floor
standards for existing OSWI reflecting the use of a medium-
efficiency wet scrubber, based on the emission limits that were
achievable considering the available HMIWI data.
    \8\ The CISWI NSPS are found at 40 CFR part 60, subpart CCCC,
and the EG are found at 40 CFR part 60, subpart DDDD (collectively
the ``CISWI standards''). The CISWI standards initially were
promulgated in 2000 (60 FR 75338) and revised in 2005 (70 FR 55568),
2011 (76 FR 15704), 2013 (78 FR 9112), and 2016 (81 FR 40956). The
CISWI standards generally apply to operating units of commercial or
industrial facilities that combust solid waste (see, e.g., 40 CFR
60.2015 and 60.2265). The CISWI standards cover certain small,
remote incinerators (SRI) that combust three TPD or less of solid
waste and are located more than 25 miles from a MSW landfill (see,
e.g., 40 CFR 60.2265).
---------------------------------------------------------------------------

    The EPA did not previously address SRI units in the OSWI standards.
At the time the OSWI standards were promulgated, we contemplated
regulating the small incinerators that are located at commercial
businesses or industrial sites as CISWI units under future revisions to
the final CISWI rules (70 FR 74882). Prior to revising the CISWI
standards, we had insufficient information about the small units
operated in the commercial and industrial facilities (e.g., operating
at oil exploration sites or oil-field based camps) to determine if they
could be treated as VSMWC units. In 2010, in connection with a CISWI
rulemaking, the EPA conducted an Information Collection Request (ICR)
to collect data for these small incinerators. The data, however, did
not provide detailed information on the type of waste these units were
burning (i.e., industrial waste or municipal-type waste generated
onsite) and the percentages of each type being combusted. Consistent
with our stated intent during the OSWI rulemaking, the EPA set the
emission standards for the SRI subcategory under the CISWI rule because
such combustion units are located at commercial/industrial facilities
(typically in isolated areas of Alaska).
    In June 2017, AOGA submitted to the EPA data that provided
additional information on waste characterization for SRI in Alaska. The
new data indicated that most such units burn more than 30-percent
municipal type solid waste; that is, the type of waste material--
regardless whether it is collected from households, the general public,
institutions, commercial or industrial operations, or some
combination--that is typically regarded as municipal waste.
    Based on the new information provided by AOGA in 2017 and a re-
evaluation of the OSWI definition of MSW and related terms, we
reconsidered the dividing line between the OSWI standards and the CISWI
standards. Units that combust more than 30 percent MSW, even units
located at commercial or industrial facilities, that otherwise meet the
definition of VSMWC (as proposed herein), including units with a
capacity of three TPD or less located away from MSW landfills, should
be subject to the OSWI rule instead of the CISWI standards.\9\
Consistent with this revised approach on the coverage or applicability
of the OSWI standards, we have considered the information from AOGA in
recalculating the MACT floors--for certain subcategories of OSWI units.
---------------------------------------------------------------------------

    \9\ Incinerators that burn less than 30-percent MSW and are
located at an industrial or commercial facility, including SRI,
would remain subject to the CISWI rule. However, the units under
consideration here are burning greater than 30-percent MSW,
according to AOGA members. For a more detailed discussion of OSWI
applicability-related issues and proposals relating to OSWI
definitions, see the discussion in section II.B.2 of this preamble.
---------------------------------------------------------------------------

    As noted in section I.F of this preamble, we have also gathered
emissions information on two OSWI units constructed since 2005, with
waste capacities greater than 10 TPD (but less than 35 TPD), including
one at a Texas facility and one at a facility in Arizona. Both of these
units are continuously-fed rotary combustors that use add-on air
pollution control devices, including wet and dry scrubbers and fabric
filters, to comply with the current OSWI standards.
    In light of the design and compliance information obtained for two
OSWI units (one in Arizona and one in Texas) and the addition of design
and operational information from the CISWI ICR and the AOGA for the SRI
units, we are proposing to subcategorize IWI and VSMWC units based on
size. The two subcategories proposed are large units that have
capacities greater than 10 TPD and small units that have capacities
less than or equal to 10 TPD. For incineration units, differences in
size typically reflect differences in operation and equipment
complexity. Units with capacities less than or equal to 10 TPD
typically feed waste to the unit in batches and some units may not even
be equipped with stacks. Units larger than 10 TPD typically feed waste
to the unit continuously or semi-continuously and also typically have
stacks or flues that can be routed to air pollution control devices.
Therefore, we are proposing subcategories as follows: (1) VSMWC units
with a capacity to combust less than or equal to 10 TPD of MSW or
refuse-derived fuel; (2) IWI units with a capacity to combust less than
or equal to 10 TPD of institutional waste; (3) VSMWC units with a
capacity to combust greater than 10 TPD of MSW or refuse-derived fuel
(but less than 35 TPD); and (4) IWI units with a capacity to combust
greater than 10 TPD of institutional waste. In connection with this
size-based sub-categorization, we are also proposing to add a
definition of ``small OSWI unit,'' a unit with a capacity less than or
equal to 10 TPD. (Accordingly, the term ``small OSWI unit'' will be
used, hereinafter, to refer to units with capacities less than or equal
to ten TPD.)
    Based on the updated inventory, emissions, and waste data provided
by AOGA, we have developed revised emission limits for existing small
OSWI units, using the average emission limitation of the best
performing 12 percent of such sources and also considering variability
in emissions, consistent with CAA section 129(a)(2). To calculate the
MACT floor emission limits for small existing OSWI sources, we
considered the available test run data \10\ provided in response to the
2010

ICR and test data from 2014 submitted in June 2017 by AOGA in their
attempt to address concerns that they had with the 2010 ICR data
pertaining to the emissions test data representativeness and waste
variability. In the MACT floor analysis, we used the run data from the
2010 and 2014 emission tests to calculate the 99th percentile upper
limits (UL) statistical interval for the best 12 percent of such
incineration units for each pollutant to address the range of operating
conditions of the incinerator. The UL is a common statistical interval
used to address variability and was the same statistical interval used
to calculate the CISWI SRI emission limits (76 FR 15723, March 21,
2011).
---------------------------------------------------------------------------

    \10\ Run data includes the emissions data captured during a
stack test comprising at least three sampling runs.
---------------------------------------------------------------------------

    In addition to addressing the range of operating conditions of the
incinerator, AOGA noted that the waste profile of the 2010 emissions
test data was not representative of the range of wastes combusted
during normal operations. The AOGA asserted that the testing sites
seemed to misinterpret the goal of the testing and may have prepared
``best case'' waste for the 2010 testing instead of a more
representative waste profile. To address this, accompanying the
additional emission tests conducted in 2014, AOGA also submitted waste
composition and elemental analysis data for nitrogen (N), Cd, Pb, Hg,
chlorine, and sulfur in the wastes combusted (sometimes also referred
to as the ``fuel'' in similar fuel variability factor (FVF)
calculations used in boiler and CISWI standards for certain
pollutants). We applied the EPA's previous analytical approach of
calculating FVF to calculate an analogous ``waste variability factor''
(WVF) for small OSWI units since these units are not designed to co-
fire waste with coal or other solid fuels, and applied this WVF to the
99-percentile UL calculation for the six pollutants that are influenced
directly by waste composition; Cd, HCl, Pb, Hg, SO2, and
NOX. A detailed discussion of the emission limit calculation
can be found in the memorandum, OSWI Emission Limit Calculations for
Existing and New Sources, which is available in the docket for this
action.
    The new proposed emission limits for the pollutants regulated under
CAA section 129(a)(4) (Cd, HCl, Pb, Hg, SO2, NOX,
PM, DF, and CO) are shown in Table 2 of this preamble. We are providing
two options for limits for DF, one based on the total mass basis (TMB)
and one based on the toxic equivalency factor (TEQ). As we have done
for other CAA section 129 standards, sources may meet one or the other
of the DF limits, but are not required to meet both. We are proposing
to apply these revised emission limits for small VSMWC and IWI units
(with capacity less than or equal to 10 TPD of solid waste), as the
data reflect our best knowledge of existing OSWI units of this size.

    Table 2--Revised OSWI Standards for Existing Small OSWI Units \1\
------------------------------------------------------------------------
                                                              Revised
             Pollutant               Concentration units  emission limit
------------------------------------------------------------------------
Cd................................  [micro]g/dscm \2\...           2,000
HCl...............................  ppmvd \3\...........             500
Pb................................  [micro]g/dscm.......          32,000
Hg................................  [micro]g/dscm.......              69
SO2...............................  Ppmvd...............             130
NOX...............................  Ppmvd...............             210
PM................................  mg/dscm.............             280
DF (TMB) \4\......................  ng/dscm \5\.........           4,700
DF (TEQ) \4\......................  ng/dscm.............              86
CO................................  Ppmvd...............             220
------------------------------------------------------------------------
\1\ Emission limits are for small existing VSMWC and IWI units with
  capacities less than or equal to 10 TPD.
\2\ Micrograms per dry standard cubic meters.
\3\ Parts per million by dry volume.
\4\ For DF, you must meet either the TMB limit or the TEQ limit.
\5\ Nanograms per dry standard cubic meters.

    We are also proposing to revise the MACT floors for new, small OSWI
units (both VSMWC and IWI). Section 129(a)(2) of the CAA requires that
MACT for new sources be no less stringent than the emissions control
achieved in practice by the best controlled similar unit. Therefore,
the approach for new sources was similar to that used with the existing
sources (i.e., 99 percentile UL with FVF applied for the pollutants
influenced by waste composition), except the top performing unit's data
were used to calculate the MACT floor emission limit instead of the
average of the best performing 12 percent of units. A detailed
discussion of the emission limit calculation can be found in the
memorandum, OSWI Emission Limit Calculations for Existing and New
Sources, which is available in the docket for this action. The new
source emission limits are shown in Table 3 of this preamble.

      Table 3--Revised OSWI Standards for New Small OSWI Units \1\
------------------------------------------------------------------------
                                                              Revised
             Pollutant               Concentration units  emission limit
------------------------------------------------------------------------
Cd................................  [micro]g/dscm.......             400
HCl...............................  ppmvd...............             210
Pb................................  [micro]g/dscm.......          26,000
Hg................................  [micro]g/dscm.......              12
SO2...............................  ppmvd...............              38
NOX...............................  ppmvd...............             180
PM................................  mg/dscm.............             210
DF (TMB)..........................  ng/dscm.............           3,100

DF (TEQ)..........................  ng/dscm.............              40
CO................................  ppmvd...............              69
------------------------------------------------------------------------
\1\ Emission limits are for small new VSMWC and IWI units with
  capacities less than or equal to 10 TPD.

    For OSWI units that are not small OSWI units, we have not
recalculated the MACT floors and are not proposing any changes to the
emissions limitations. As mentioned before, large VSMWC and IWI units
(with capacities greater than 10 TPD) have a different design and mode
of operation than small OSWI units. We do not have sufficient
information on these units that would enable us to revise the MACT
floor for these existing OSWI units, and we are not proposing any
changes to the current OSWI limits for existing sources for these
units. Emissions data for two units in this size category demonstrate
that sources require use of add-on control devices similar to those
considered in the development of the 2005 OSWI standards to meet the
emission limits, which supports our decision to retain the 2005 OSWI
emission limits for this OSWI subcategory. Information provided on the
units shows that the units are meeting the current OSWI emission limits
and are in compliance with the current rule. We are not proposing any
changes to the current OSWI emission limits for VSMWC and IWI units
with capacities greater than 10 TPD (new and existing).
    The EPA also examined whether it was appropriate to adopt more
stringent ``beyond-the-floor'' regulatory options to determine MACT.
Unlike the floor minimum stringency requirements, the EPA must consider
various impacts of the more stringent regulatory options in determining
whether MACT standards are to reflect ``beyond-the-floor''
requirements, including considering the costs, non-air quality health
and environmental impacts, and energy requirements of such more
stringent control. Small OSWI units often are of very basic,
rudimentary design and function, as discussed in section II.B.4 of this
preamble. Requiring additional controls on small OSWI units is
infeasible or simply would be cost prohibitive. For OSWI units with
capacities greater than 10 TPD, the 2005 final rule already
incorporated beyond-the-floor requirements. We do not have sufficient
information for large OSWI units that would enable us to revise the
beyond the floor limits in this action. However, based on the
information we have from the 2005 rule, requiring any further controls
would likely only provide minimal emissions reductions with substantial
cost investments. Considering these factors, we concluded that revised
beyond-the-floor limits are unreasonable for the OSWI subcategories. A
more detailed discussion of the beyond-the-floor analyses is provided
in the memordandum, OSWI Emission Limit Calculations for Existing and
New Sources, which is available in the docket for this action.
    In the 2005 final OSWI rule, we also established opacity standards
for ACI units that would otherwise meet the definitions of IWI or VSMWC
units, but burn only 100-percent wood wastes, 100-percent clean lumber,
100-percent yard waste, or 100-percent mixture of only wood waste,
clean lumber, and yard waste. We are not proposing any changes to the
opacity standards for these units. However, ACIs that do not burn only
100-percent wood wastes, clean lumber, or yard wastes and that would
meet the definition of an IWI or VSMWC unit would be required to meet
the applicable OSWI standards.
    The emission limits, including the proposed revised limits for
small OSWI units and the (unchanged) limits for units with capacities
greater than 10 TPD, are summarized in Table 4 of this preamble.

                 Table 4--Limits for OSWI Units, Including Proposed Limits for Small OSWI Units
----------------------------------------------------------------------------------------------------------------
                                                   Existing VSMWC and IWI units       New VSMWC and IWI units
           Pollutant              Concentration  ---------------------------------------------------------------
                                      units          Small \1\       Large \2\       Small \1\       Large \2\
----------------------------------------------------------------------------------------------------------------
Cd............................  [micro]g/dscm...           2,000              18             400              18
HCl...........................  ppmvd...........             500              15             210              15
Pb............................  [micro]g/dscm...          32,000             226          26,000             226
Hg............................  [micro]g/dscm...              69              74              12              74
SO2...........................  ppmvd...........             130             3.1              38             3.1
NOX...........................  ppmvd...........             210             103             180             103
PM............................  mg/dscm.........             280              30             210              30
DF (TMB)......................  ng/dscm.........           4,700              33           3,100              33
DF (TEQ)......................  ng/dscm.........              86            -\3\              40            -\3\
CO............................  ppmvd...........             220              40              69              40
----------------------------------------------------------------------------------------------------------------
\1\ Small units include those with capacity less than or equal to 10 TPD.
\2\ Limit basis is from 2005 OSWI Rule. For PM, the 2005 OSWI standard is shown as mg/dscm rather than grains
  per dscf.
\3\ DF TEQ basis was not calculated for the 2005 rule.

2. Proposed Revisions to Applicability of OSWI Requirements
    We are proposing two changes to the applicability of the OSWI
standards in order to resolve inconsistent definitions between OSWI and
other CAA section 129 rulemakings, and update aspects of the rule that
we have reconsidered based on new data. The proposed changes include
(1) removing the definition of the term ``collected from'' as used in,
and limiting the definition of, ``municipal solid waste'' in order to
place the focus on the source and type or nature of the waste, rather
than the manner in which is it ``collected'' and (2) modifying the OSWI
definition of

``municipal waste combustion unit'' to make it clear that pyrolysis/
combustion units are not OSWI units.
    First, we are clarifying that the applicability of the OSWI
standards to VSMWC units is based on the source and type or nature of
waste incinerated rather than the particular manner in which the waste
is collected. The regulatory history of the MWC rules indicates that
the EPA intended to determine the applicability of the MWC rule based
on the type of waste combusted in a unit and not based on the location
of the incineration unit (54 FR 52261, December 20, 1989). The 2005
OSWI rule finalized a definition of ``municipal solid waste'' that was
similar to the definition of ``municipal waste'' provided in CAA
section 129(g)(5), but interpreted this, for the purposes of VSMWC
applicability under OSWI, to mean that the municipal waste must be
``collected from'' certain or multiple sites. We have since re-
evaluated our interpretation in OSWI where the rule explains municipal
waste must be limited to those collected from outside the site of the
incinerator. Other existing CAA section 129 incinerator rules do not
necessarily place the same emphasis on where the waste is collected.
The principal MWC rules, for example, do not focus on or even define
``collected from,'' and, instead, more broadly include materials
discarded by a wide range of sources, regardless of how or where the
waste may be ``collected'' (see, e.g., 40 CFR 60.51b and 60.1465). We
are proposing to modify the definitions in the OSWI standards to remove
the specific definition of ``collected from'' and, thus, to eliminate
the limitation that waste may not be burned at the same site where it
is generated in order for it to be considered MSW.
    We are, accordingly, proposing a different approach to the
treatment of MSW under the OSWI standards than we opted to pursue when
the standards were promulgated. There, we stated that ``small
incinerators that are located at commercial business (such as stores,
restaurants and apartments) or industrial sites are not VSMWC units
because they do not burn waste which has been `collected from.' '' (70
FR 74882). Under this proposal, such incinerators would no longer be
subject to this ``collected from'' limitation and would qualify as
VSMWC (provided these units burn more than 30-percent MSW).\11\ We
believe this approach is more consistent with the EPA's other CAA
section 129 MWC rules. We also believe, on further review, that this
approach is more consistent with the CAA section 129 definition of
``municipal waste.'' Section 129(g)(5) of the CAA essentially defines
the term ``municipal waste'' to mean refuse ``collected from the
general public and from residential, commercial, institutional, and
industrial sources consisting of paper, wood, yard wastes, food wastes,
plastics, leather, rubber and other combustible materials and non-
combustible materials such as metal, glass and rock.'' We do not read
this definition as necessitating that, to constitute MSW, the material
or refuse must be a cumulative collection of refuse from each and every
one of the sources identified (that is, the ``general public,''
``residential,'' or ``commercial'' sources) or even necessarily of
multiple such sources. Moreover, the term ``collected from'' is not
defined in the CAA, and we do not read it as necessarily requiring (for
waste to be considered MSW) that the waste must be transferred from one
site and burned at another site.
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    \11\ An incinerator is not considered to be combusting MSW ``if
it combusts a fuel feed stream, 30 percent or less of the weight of
which is comprised, in aggregate, of municipal solid waste.'' See,
e.g., 40 CFR 60.2977.
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    Next, we are proposing to revise the OSWI definition of ``municipal
waste combustion unit'' to remove the reference to ``pyrolysis/
combustion units.'' The term is not defined in the current regulation
and there is no similar specific reference to such units in the
institutional waste incineration unit definition. In the preamble to
the OSWI standards, we briefly stated that ``pyrolysis/combustion units
(two chamber incinerators with a starved air primary chamber followed
by an afterburner to complete combustion) within the VSMWC and IWI
subcategories are considered OSWI units'' (70 FR 74876 and 74877). In
the recent past, however, the EPA has received several inquiries about
OSWI applicability to pyrolysis/combustion units, and we believe that
there is considerable confusion in the regulated community regarding
the reference to pyrolysis/combustion units in the definition of
municipal waste combustion unit. Upon further review of the language in
the final OSWI rule (70 FR 74876 and 74877), we believe the reference
to pyrolysis/combustion units as MWC should not apply to OSWI units
because such units are used to combust uncontained gases and do not
involve the combustion of solid waste as defined in the OSWI rule. See
70 FR 74877 (where we noted that units that are used to combust
uncontained gases and are not used to dispose of solid waste generally
are not subject to the OSWI standards).
    An OSWI unit is either a VSMWC or an IWI, and both types of units
combust ``solid waste.'' Solid waste includes solid, liquid, and
semisolid material. Solid waste also includes ``contained gaseous
material,'' defined as gases that are in a container when that
container is combusted (40 CFR 60.2977, 60.3078).
    The combustion of uncontained gases in pyrolysis/combustion units
is inconsistent with the definition of solid waste and the associated
definition of ``contained gaseous material'' in OSWI, and therefore,
with solid waste combustion for the purpose of the OSWI rule. The EPA
understands pyrolysis to be a process that takes place in an inert
environment. In a closely coupled pyrolysis/combustion chamber, the
gaseous material comes out of the pyrolysis chamber and immediately is
incinerated in the combustion chamber. The pyrolysis gas is not placed
into a container and then combusted. Therefore, the pyrolysis gas in
the closely coupled pyrolysis/combustion chamber is not ``contained
gaseous material,'' as referenced in the definition of solid waste. We
noted in connection with the promulgation of the OSWI standards that
thermal oxidizers, catalytic oxidizers, and flameless thermal oxidizers
are not considered to be subject to the OSWI rule if these units are
used to combust uncontained gas from an industrial process (70 FR
74877). Moreover, unlike combustion, the pyrolysis process is
endothermic and does not require the addition of oxygen (i.e. the
partial pressure of oxygen during a pyrolysis process is maintained
close to zero). Based on this understanding, we recognize that the
pyrolysis process, by itself, is not combustion. In summary, because
the pyrolysis itself is not combustion and pyrolysis gases are not a
``solid waste'' under OSWI, a pyrolysis-combustion unit should not be
referenced in the definition of MWC unit for the purposes of the OSWI
rule.\12\ Accordingly, we are

proposing to revise the definition of ``municipal waste combustion
unit'' in 40 CFR 60.2977 and 40 CFR 60.3078 to remove the reference to
``pyrolysis/combustion units'' from the definition, reflecting our view
that such units should not be regarded as municipal waste combustion
units under the OSWI rule.
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    \12\ Discarded material that is processed in such a unit would
still be a solid waste under the Resource Conservation and Recovery
Act (RCRA), and, therefore, subject to state RCRA Subtitle D solid
waste management program requirements. In the case of hazardous
waste, RCRA sections 3002(a) and 3004(a) grant the EPA the authority
to control gaseous emissions from hazardous waste management as may
be necessary to protect human health and the environment. RCRA
sections 3004(n), and (o)(1)(B), further direct the EPA to regulate
air emissions from, respectively, hazardous waste treatment, storage
and disposal facilities, and hazardous waste incinerators. The
authority provided in RCRA section 3004(q) to regulate fuel produced
from hazardous waste also encompasses gaseous fuels (when they are
produced from hazardous wastes). The authority provided in RCRA
section 3004(u) to control ``releases'' of hazardous constituents
from solid waste management units at a facility seeking a RCRA
permit also encompasses gaseous releases (when the gases are
hazardous constituents). The authority granted under these sections
of the statute is independent of the EPA's authorities over solid
waste. As an example, the EPA has authority to regulate emissions
generated during treatment of hazardous waste, including
volatilization and incineration of hazardous waste.
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3. Proposed Removal of SSM Provisions
    Currently, the OSWI standards do not apply during SSM periods (see
40 CFR 60.2918, 60.3025). The EPA proposes to eliminate this limitation
or qualification on the applicability of the OSWI standards. The EPA
proposes this change in light of the 2016 remand and certain legal
developments, including a decision by the D.C. Circuit that invalidated
certain regulations related to SSM in the 40 CFR part 63 General
Provisions (Sierra Club v. EPA, 551 F.3d 1019 (2008)). While the
decision did not specifically address the SSM provisions in the OSWI
standards, it calls those provisions into question.
    We are not proposing separate emission standards for OSWI units
that would apply during SSM periods. We determined that OSWI units will
be able to meet the emission limits during periods of startup because
most units burn natural gas or clean distillate oil to start, and waste
is not added until the unit has reached combustion temperatures.
Emissions from burning natural gas or distillate fuel oil would
generally be significantly lower than from burning solid wastes. During
shutdown periods, emissions are also generally significantly lower than
emissions during normal operations because the materials in the
incinerator will be almost fully combusted before shutdown occurs.
Control of the lower emissions during startup and shutdown should be
able to be accomplished using the same technological controls required
for emissions during normal operations. Furthermore, the approach for
establishing the revised MACT floors for OSWI units ranked individual
OSWI or similar units based on actual performance for each pollutant,
with an appropriate accounting of emissions variability. Because we
accounted for emissions variability and established appropriate
averaging times to determine compliance with the proposed OSWI
standards, we believe we have adequately addressed any minor
variability that may potentially occur during startup or shutdown.
However, we note that we do not have available data for OSWI units
during periods of startup and shutdown. We request comment on the
proposed removal of the SSM provisions and the proposal to leave in
place the OSWI standards during SSM periods, including any additional
information for consideration for startup and shutdown periods for OSWI
units.
    Periods of startup, normal operations, and shutdown are all
predictable and routine aspects of a source's operations. Malfunctions,
in contrast, are neither predictable nor routine. Instead they are, by
definition, sudden, infrequent, and not reasonably preventable failures
of emissions control, process, or monitoring equipment (see 40 CFR
60.2). The EPA interprets CAA section 129 as not requiring emissions
that occur during periods of malfunction to be factored into
development of CAA section 129 standards. Under CAA section 129,
emissions standards for new sources must be no less stringent than the
level ``achieved'' by the best controlled similar source and for
existing sources generally must be no less stringent than the average
emission limitation ``achieved'' by the best performing 12 percent of
sources in the category. There is nothing in CAA section 129 that
directs the Agency to consider malfunctions in determining the level
``achieved'' by the best performing sources when setting emission
standards. As the D.C. Circuit has recognized, the phrase ``average
emissions limitation achieved by the best performing 12 percent of''
sources ``says nothing about how the performance of the best units is
to be calculated.'' Nat'l Ass'n of Clean Water Agencies v. EPA, 734
F.3d 1115, 1141 (DC Cir. 2013). While the EPA accounts for variability
in setting emissions standards, nothing in CAA section 129 requires the
Agency to consider malfunctions as part of that analysis. The EPA is
not required to treat a malfunction in the same manner as the type of
variation in performance that occurs during routine operations of a
source. A malfunction is a failure of the source to perform in a
``normal or usual manner'' and no statutory language compels the EPA to
consider such events in setting CAA section 129 standards. The EPA's
approach to malfunctions in the analogous circumstances (setting
``achievable'' standards under CAA section 112) has been upheld as
reasonable by the D.C. Circuit in U.S. Sugar Corp. v. EPA, 830 F.3d
579, 606-610 (2016).
    As the D.C. Circuit recognized in U.S. Sugar Corp., accounting for
malfunctions in setting standards would be difficult, if not
impossible, given the myriad different types of malfunctions that can
occur across all sources in the category and given the difficulties
associated with predicting or accounting for the frequency, degree, and
duration of various malfunctions that might occur. Id. at 608 (``the
EPA would have to conceive of a standard that could apply equally to
the wide range of possible boiler malfunctions, ranging from an
explosion to minor mechanical defects. Any possible standard is likely
to be hopelessly generic to govern such a wide array of
circumstances.'') As such, the performance of units that are
malfunctioning is not ``reasonably'' foreseeable. See, e.g., Sierra
Club v. EPA, 167 F.3d 658, 662 (D.C. Cir. 1999) (``The EPA typically
has wide latitude in determining the extent of data-gathering necessary
to solve a problem. We generally defer to an agency's decision to
proceed on the basis of imperfect scientific information, rather than
to `invest the resources to conduct the perfect study. '') See also,
Weyerhaeuser v. Costle, 590 F.2d 1011, 1058 (D.C. Cir. 1978) (``In the
nature of things, no general limit, individual permit, or even any
upset provision can anticipate all upset situations. After a certain
point, the transgression of regulatory limits caused by `uncontrollable
acts of third parties,' such as strikes, sabotage, operator
intoxication or insanity, and a variety of other eventualities, must be
a matter for the administrative exercise of case-by-case enforcement
discretion, not for specification in advance by regulation.''). In
addition, emissions during a malfunction event can be significantly
higher than emissions at any other time of source operation. For
example, if an air pollution control device with 99-percent removal
goes off-line as a result of a malfunction (as might happen if, for
example, the bags in a baghouse catch fire) and the emission unit is a
steady state type unit that would take days to shut down, the source
would go from 99-percent control to zero control until the control
device was repaired. The source's emissions during the malfunction
would be 100 times higher than during normal operations. As such, the
emissions over a 4-day malfunction period would exceed the annual
emissions of the source during normal operations. As this example
illustrates,

accounting for malfunctions could lead to standards that are not
reflective of (and significantly less stringent than) levels that are
achieved by a well-performing non-malfunctioning source. It is
reasonable to interpret CAA section 129 to avoid such a result. The
EPA's approach to malfunctions is consistent with CAA section 129 and
is a reasonable interpretation of the statute.
    Although no statutory language compels the EPA to set standards for
malfunctions, the EPA has the discretion to do so where feasible. For
example, in the Petroleum Refinery Sector Risk and Technology Review,
the EPA established a work practice standard for unique types of
malfunction that result in releases from pressure relief devices or
emergency flaring events because the EPA had information to determine
that such work practices reflected the level of control that applies to
the best performers. 80 FR 75178, 75211 through 14 (December 1, 2015).
The EPA will consider whether circumstances warrant setting standards
for a particular type of malfunction and, if so, whether the EPA has
sufficient information to identify the relevant best performing sources
and establish a standard for such malfunctions. We note that there are
no provisions for establishing work practice standards under CAA
section 129.
    In the event that a source fails to comply with the applicable CAA
section 129 standards as a result of a malfunction event, the EPA would
determine an appropriate response based on, among other things, the
good faith efforts of the source to minimize emissions during
malfunction periods, including preventative and corrective actions, as
well as root cause analyses to ascertain and rectify excess emissions.
The EPA would also consider whether the source's failure to comply with
the CAA section 129 standard was, in fact, sudden, infrequent, not
reasonably preventable, and was not instead caused, in part, by poor
maintenance or careless operation. 40 CFR 60.2 (definition of
malfunction).
    If the EPA determines in a particular case that an enforcement
action against a source for violation of an emission standard is
warranted, the source can raise any and all defenses in that
enforcement action and the federal district court will determine what,
if any, relief is appropriate. The same is true for citizen enforcement
actions. Similarly, the presiding officer in an administrative
proceeding can consider any defense raised and determine whether
administrative penalties are appropriate.
    In summary, the EPA's interpretation of the CAA and, in particular,
CAA section 129, is reasonable and encourages practices that will avoid
malfunctions. Administrative and judicial procedures for addressing
exceedances of the standards fully recognize that violations may occur
despite good faith efforts to comply and can accommodate those
situations. U.S. Sugar Corp. v. EPA, 830 F.3d 579, 606-610 (2016).
    For these reasons, we are proposing to remove and reserve 40 CFR
60.2918 and 40 CFR 60.3025, which provided exceptions for SSM. We are
proposing minor harmonizing revisions to other rule requirements that
reference SSM, such as revisions to the definition of ``Deviation'' to
remove language for periods of SSM, for consistency with these changes.
4. Proposed Revisions to Testing and Compliance
    For small OSWI units, we are proposing alternatives to conducting
the initial and annual performance tests and to remove the requirements
to install, calibrate, maintain, and operate continuous emissions
monitoring systems (CEMS). The OSWI standards currently require owners
and operators of OSWI units to conduct initial and annual performance
tests to demonstrate compliance (40 CFR 60.2927, 60.2932 and 60.3030,
60.3033). Owners and operators may conduct performance tests less often
than annually for a given pollutant if they are able to demonstrate
compliance with the emissions limitations for three consecutive annual
tests (40 CFR 60.2934, 60.3035). The OSWI standards also require CEMS
for CO and oxygen (40 CFR 60.2939, 60.3038).
    We are proposing a new substitute means of compliance demonstration
for small OSWI units, as we recognize that testing can impose
substantial financial burdens and technical challenges on owners and
operators of these sources. Based on the limited information available,
we expect that most OSWI units are likely small incinerators that are
not equipped with stacks from which to sample emissions during a
performance test, and a stack or extension would be needed in order to
perform the testing required by the OSWI standards. In some instances,
it physically may not be possible to equip the incinerator with a
stack, and in other cases, costs for doing so may be prohibitive.
Transporting, installing, and supporting the extension for testing in
the field can present additional issues, such as space or property
constraints that may require additional construction of scaffolding,
ducting, or modifications to underlying structures to install the
appropriate extensions and sampling ports.\13\ Additionally, many of
these small OSWI units are located in remote and difficult to access
areas of the country, and it is difficult to mobilize stack testing
crews to some of these locations.
---------------------------------------------------------------------------

    \13\ The OSWI standards are found in 40 CFR part 60, subparts
EEEE (NSPS) and FFFF (EG). In addition, subpart A (General
Provisions) of part 60 contains various generally-applicable
provisions, including provisions relating to performance testing
(see, for example, 40 CFR 60.8). These generally-applicable
performance testing provisions require, in part, owners and
operators to provide performance testing facilities, including
sampling ports. We believe, however, that for small OSWI units there
could be significant challenges to conducting such modifications in
the field to fit units at every site. In any event, the application
of the General Provisions in subpart A to the other part 60 subparts
is subordinate to the specific provisions found in the other
subparts, such as the OSWI standards. See, for example, 40 CFR
60.8(b) (performance test shall be conducted in accordance with the
methods and procedures in each applicable subpart), 60.8(f)
(performance testing shall be conducted in a prescribed manner,
unless otherwise specified in the applicable subpart), and 60.11
(compliance shall be determined in accordance with 40 CFR 60.8,
unless otherwise specified in the applicable standard). Moreover,
the EPA retains the authority to limit or modify the application of
subpart A in subsequent rulemaking, including rulemaking relating to
other part 60 subparts, such as the OSWI standards. In the event of
a conflict between the performance testing provision of subpart A
and the provisions of subparts EEEE and FFFF, the provisions of the
source specific subparts (here, EEEE and FFFF) control.
---------------------------------------------------------------------------

    These technical and economic infeasibilities are magnified for
existing sources, which have previously installed units that may have
never been equipped with a stack and for which additional space or
property modifications may be infeasible. Further, owners and operators
may find it economically infeasible to conduct initial or annual
performance tests of these small units due to the cost of stack
testing. We believe that similar difficulties may arise in connection
with monitoring, including installation and operation of CEMS. Although
we recognize these challenges exist for certain sources, adequate
demonstration of initial and on-going compliance is necessary.\14\
Therefore, we are proposing alternatives to the testing and monitoring
requirements to provide

regulatory flexibilities for small OSWI units.
---------------------------------------------------------------------------

    \14\ CAA 129(c) requires, in part, the EPA to include emissions
monitoring as part of solid waste incinerator standards. This
requirement has been construed as requiring assurance of compliance
with emission standards. Nat'l Ass'n of Clean Water Agencies v. EPA,
734 F.3d 1115, 1160 (DC Cir. 2013). The EPA believes that, for the
other solid waste incineration source category, the package of
testing, monitoring, reporting, and recordkeeping requirements
associated with the proposed substitute means of compliance testing
for small OSWI units will adequately assure compliance with the
standards.
---------------------------------------------------------------------------

    At present, the OSWI standards require new sources to conduct
initial performance testing within 60 days after the OSWI unit reaches
the charge rate by which it will operate, but not later than 180 days
after initial startup (40 CFR 60.2928); existing sources must conduct
initial performance testing no later than 180 days after the final
compliance date. We are proposing to retain this requirement, but we
are also proposing--for small OSWI units--to add a substitute means of
compliance demonstration, under which such initial performance testing
would not be required. In lieu of that initial performance testing,
owners and operators of small OSWI units would have the option to
submit detailed information concerning the unit--including the make,
model and manufacturer of the unit, and the type and capacity of the
unit, information on the unit's air pollution control devices (if any),
waste type and quantity information, and the charge rate--and to
identify in the EPA's WebFIRE database a representative performance
test.\15\ The test must be representative for the small OSWI unit in
terms of similar throughput, method of processing and burning waste,
operating temperatures, types of wastes or supplemental fuels burned,
and waste profiles. If there is no representative performance test
available in the WebFIRE database, the small OSWI unit cannot use the
substitute means of compliance demonstration and must comply with the
initial performance testing requirements.
---------------------------------------------------------------------------

    \15\ Some tests in the WebFIRE database may not qualify for use
as a representative performance test. Representative performance
tests must be conducted according to the requirements in the OSWI
rule, demonstrate compliance with the OSWI standards, and include
the following information in the report: Unit design (including air
pollution control devices), charge rate during the test, type of
operation, combustion temperature during the test, types of waste
burned during the test and the relative amount of each waste to the
total waste burned, type and amount of supplemental fuels used
during the test, and, if the tested unit has an air pollution
control device, the operating parameter data for the control device
during the test.
---------------------------------------------------------------------------

    To use this alternative option, the owner/operator must submit a
notification including the manufacturer, make, model, and type of unit,
and documentation that the capacity of the unit is less than or equal
to 10 TPD. We are proposing that owners and operators of new small OSWI
units (constructed after August 31, 2020) and small OSWI units modified
or reconstructed six months after the effective date of the final rule
would be required to either complete their initial performance test
within 60 days after the unit reaches the charge rate at which it will
operate, but no later than 180 days after its initial startup,\16\ or
submit a notification of intention to use the substitute means of
compliance demonstration to the Administrator within 6 months after the
date of publication of the final rule (currently estimated by the EPA--
depending on the actual date of publication of the final rule--to be on
or about November 30, 2021), or within 60 days after initial startup,
whichever of these dates is later. Owners and operators of existing
small units (constructed on or before August 31, 2020) would not be
required to submit a notification of intention to the Administrator,
but would be required to identify the results of an existing
performance test in the EPA's WebFIRE that is representative of their
OSWI unit or conduct an initial performance test, no later than 3 years
after a state plan is approved or no later than 5 years after the date
of promulgation of the final rule, whichever of these dates is earlier.
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    \16\ For units that start-up between August 31, 2020 and the
date that is 6 months after publication of the final rule, the
initial performance test must be conducted within 60 days after your
OSWI unit reaches the charge rate at which it will operate, but no
later than 180 days after its initial startup, or by the date 240
days after publication of the final rule (currently estimated by the
EPA to be on or about February 28, 2022), whichever date is later.
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    The proposed substitute means of compliance demonstration relies on
the availability of the results of performance tests conducted on
potentially representative sources in the EPA's WebFIRE database. One
way the EPA envisions this option could be implemented is through one
or more testing coordinators that would develop a testing protocol and
conduct performance tests for representative units from similar source
groups.17 18 For example, each owner/operator opting to use
the substitute means of compliance demonstration would submit to a
testing coordinator information on its small OSWI unit, including unit
design, operations information and waste profiles. It is our
expectation that the testing coordinator would review the data provided
and identify a representative unit for each similar source group,
establish the waste profile for the similar source group, and
coordinate and/or conduct the performance test on the representative
unit from the similar source group. The results of the test could then
be used to demonstrate initial compliance by owners and operators of
any small OSWI unit for which the test is representative. To aid
implementation of this option, the EPA intends to provide a grant or
contract to testing coordinators. To conserve resources, if there are
multiple testing coordinators, the testing coordinators should work
together in conducting performance tests in order to provide
performance test results that will be representative for the largest
number of small OSWI units.
---------------------------------------------------------------------------

    \17\ A ``testing coordinator'' may be, for example, a state or
university that would collect waste data from a group of sources,
form similar groups of facilities based of the information provided,
develop a testing protocol, and conduct performance tests for
representative units from similar source groups.
    \18\ ``Similar source groups'' may include units of similar
throughput, method of processing and burning waste, operating
temperatures, waste variability, and estimated waste profiles. It is
expected that a performance test conducted on one unit in a similar
source group would likely be representative for all of the units in
the similar source group. The proposed option would allow for a
testing coordinator to have some latitude to determine what
constitutes a similar source group. For example, the testing
coordinator would have the discretion to test representative units
for existing sources (constructed on or before August 31, 2020), and
new sources (constructed after August 31, 2020), from similar source
groups separately. Alternatively, the testing coordinator might be
able to select a new source (e.g., a model unit constructed after
August 31, 2020, that has a similar design that would be carried
forward into future years) from a similar source group that is also
similar to existing sources. In this latter case, if the new unit
tested is able to demonstrate initial compliance with the emissions
limits for VSMWC and IWI units under the NSPS and EG, then both the
existing and new units described by the similar source group may be
able to use the test data to demonstrate initial compliance.
---------------------------------------------------------------------------

    Another way that the EPA envisions this representative testing
alternative might be implemented is if owners and operators of small
OSWI units that are similar in design and operation and burn the same
waste types combine resources. One small OSWI unit in the group would
be tested, and once the results are available in WebFIRE, that
performance test would be used to demonstrate initial compliance for
any small OSWI unit for which the test is representative.
    Beginning on the effective date for new sources (6 months after
publication of the final rule in the Federal Register), and until the
owner/operator identifies a representative performance test, each
owner/operator of a small OSWI unit would be required to collect data
on a weekly basis to characterize the unit operations and the waste
profiles for the OSWI unit. The waste profile information would be used
to capture the differing waste streams and waste variability for the
unit in order to develop a representative waste profile. The owner/
operator would use these data to locate the results of a representative
performance test in the

EPA's WebFIRE database. The owner/operator would submit information on
the representative performance test and documentation of how the
performance test is representative for their small OSWI unit (e.g.,
based on the unit type and design, charge rate, operating temperatures,
types of waste burned, and any air pollution control devices) to the
Administrator through the EPA's Central Data Exchange (CDX) using the
Compliance and Emissions Data Reporting Interface (CEDRI). Owners and
operators would maintain a record (i.e., copy) of the representative
performance test report (acquired from the EPA's WebFIRE database) and
the submitted documentation of how the test is representative.
    Because we anticipate this approach would need to afford time for
testing coordinators to determine similar source groups, develop
testing protocols, and coordinate with each other, owners and operators
of existing and new small units who wish to use the substitute means of
compliance demonstration are encouraged to submit their notification of
intent to use the substitute means of compliance demonstration and
identify their waste variability and waste characterization and profile
data as soon as possible following the promulgation of the final rule.
We note that, if this alternative initial compliance option is
finalized, owners and operators who do not provide their initial waste
characterization data to a testing coordinator in a timely manner could
miss the opportunity to avail themselves of this option due to the
amount of planning, time, and resources required for coordinators to
perform these tests as well as the fact that their unit may not be of
the similar source group tested. Owners and operators who cannot find a
representative test conducted for a unit that is similar to their units
would be required to conduct their own initial performance tests.
Because the compliance date for new sources is earlier than the
compliance date for existing sources, and it is uncertain how many
tests could be conducted with the EPA-supplied grant or contract money,
owners and operators of existing sources are encouraged to start
collecting information that would be useful in conducting similar
sources tests and submit this information to the testing coordinators
as soon as possible. This will greatly increase the likelihood that a
representative test is available in the WebFIRE database prior the
compliance deadline.\19\
---------------------------------------------------------------------------

    \19\ When deciding the sources to test, a testing coordinator
has multiple options: (1) Select an existing source similar to other
existing sources; (2) select a unit that is representative of both
new and existing sources; (3) select a new source that is similar to
other new sources; and (4) select a unit with a design that would be
carried forward into future years. The decision on which sources
will be tested will be based in part on the pool of data that is
available to the testing coordinator at the time that the testing
protocols are developed. If the testing coordinator does not have
data on existing sources, it may not be feasible to conduct
performance tests that are representative for any existing units. If
a performance test is conducted on an existing unit, it must, among
other things, demonstrate initial compliance with the emissions
limits for new units in order for a new unit to use it as a
representative performance test.
---------------------------------------------------------------------------

    We anticipate that the testing coordinators would be able to
complete testing on OSWI units that are representative of most existing
and new small units and submit the results of the testing within 18
months of the date of publication of the final rule. The testing
results for these potentially representative units will be submitted to
the EPA's CEDRI, and would then be available to owners and operators in
the EPA's WebFIRE database. (See section II.B.6 of this preamble for a
discussion of electronic reporting.) We are proposing a time period of
21 months following the date of publication of the final rule in the
Federal Register or 60 days after the OSWI unit reaches the maximum
charge rate at which it will operate, but no later than 180 days after
initial startup, whichever date is later, for owners and operators of
small OSWI unts to identify a representative performance test in
WebFIRE and submit information to the Administator identifying the
representative performance test. This period allows time for a testing
coordinator conducting the test to develop the testing protocol,
conduct performance tests, and electronically submit the results of the
test through CEDRI; for the EPA to transfer these results to the EPA's
WebFIRE database; and for owners and operators to find a representative
performance test and submit information on how it is representative to
the Administrator.
    For demonstrating continuous compliance, we are also proposing, for
small OSWI units, an alternative waste characterization option in lieu
of the current annual performance testing requirements, as many of the
concerns about the availability or feasibility of initial testing for
small OSWI units also apply to annual testing. We are proposing the
alternative continuous compliance option for small OSWI units in lieu
of annual testing (or the requirements to conduct testing less often
than annual for specific pollutants) because the option is a more
readily available compliance option for units with rudimentary designs
or units without a stack and the costs associated with waste stream
characterization are less prohibitive than those for an annual stack
test. This alternative continuous compliance demonstration option
includes periodic, robust operational recordkeeping in lieu of
conducting an annual performance test. Following the facility's initial
performance test or representative performance test (if using the
substitute means of compliance demonstration), an owner/operator would
demonstrate continuous compliance through recordkeeping. The
recordkeeping requirements would include recording the source-specific
waste profiles and incinerator unit operating parameters, including the
daily average charge rate and the 3-hour average combustion chamber
temperature of the unit. To demonstrate compliance, the weekly records
of the source-specific waste profile would need to indicate that the
waste combusted is consistent, within +/- 15 percent by weight, of the
percentage established for that waste category according to the waste
profiles established during the representative performance test (if
using the substitute means of compliance demonstration) or the
facility's initial performance test.\20\ Additionally, the records
would need to demonstrate that the unit is operated within the charge
rate and temperature ranges established during the initial performance
test or the representative performance test.
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    \20\ If, for example, the paper component of the waste stream
during initial testing was 20 percent then burning waste streams
with a paper component between 5 and 35 percent of the total waste
stream would be acceptable weekly operation and, assuming all other
requirements are met, additional testing would not be required for
the source.
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    If the facility anticipates combusting a waste stream with a
different profile, the owner/operator would be required to conduct a
performance test of the unit with a waste stream representative of the
new waste profile, or, alternatively, identify a representative
performance test report in the WebFIRE database, before combusting the
modified waste stream (i.e., the owner or operator must identify that
the unit is of similar throughput, method of processing and burning
waste, charge rate, operating temperatures, waste management plan,
estimated waste variability and waste profiles to the representative
unit). Similarly, if the facility anticipates exceeding or operating
outside of the established operating parameter ranges, the owner/
operator would be required to conduct a performance test of the unit
while operating at the new parameter limits (or find a representative

performance test with those operating parameter limits in the WebFIRE
database) to confirm that the unit continues to meet the OSWI emission
standards under the new operating parameter limits. Failure to comply
with the retesting requirement would constitute a deviation from the
OSWI standards.
    Finally, we are proposing to modify the monitoring requirements for
small OSWI units that use the alternative continuous compliance option
in lieu of complying with the annual performance testing requirements
by removing the requirement for CO and oxygen CEMS. We are proposing
this change for the same reasons that we are proposing an alternative
to the annual performance test. In addition to the cost of maintaining
CEMS, part of calibrating a CEMS generally requires an annual stack
test to verify the operation of the CEMS. Relieving owners and
operators of small OSWI units of the obligation to conduct an annual
performance test without likewise removing the requirement for CEMS,
which includes performing an annual stack test, would not achieve the
stated goals and benefits of removing the annual performance test.
    For OSWI units other than small OSWI units, we are also proposing
that such units may use CO CEMS data in lieu of initial and annual
testing for CO, provided the CEMS has been previously certified and is
meeting the ongoing quality assurance/quality control requirements.
Facilities that use this option would be allowed to use a 12-hour
rolling average of the 1-hour arithmetic average CEMS data to determine
compliance with the CO emission limitations. However, the initial
performance evaluation (certification) must be conducted prior to
collecting CEMS data for the initial compliance demonstration. Under
the proposed rules, such units could also use CO CEMS data in lieu of
conducting an annual performance test for CO. This proposed change
would provide flexibility for sources and reduce the burden associated
with testing, while assuring compliance based on continuously measured
emissions data.
5. Proposed Recordkeeping and Reporting Revisions
    We are proposing several revisions to the recordkeeping and
reporting requirements. A number of proposed recordkeeping changes are
associated with the proposal to establish--for small OSWI units--a
substitute compliance demonstration option (for initial performance
testing, as well as continuous compliance testing). For small OSWI
units using the substitute compliance demonstration process, we propose
(in connection with the initial compliance test requirement) owners and
operators will be required to maintain records of the notification of
intent to use the substitute means of compliance demonstration and the
documentation demonstrating the design, operation, and unit capacity,
copies of the initial waste characterization and operating data, and
documentation related to the representative (substitute) performance
test and how the test is representative of the unit. The new proposed
recordkeeping requirements for owners and operators of small OSWI
units--and associated with the proposed substitute continuous
compliance requirements--include records on such particulars as unit
start and end times of operation, the quantity or weight of each waste
type (e.g., pounds of solid waste, food waste, wood or yard waste), the
quantities of supplemental fuels burned (flow rate or percentage of
operating time), percentage of each waste type of total waste burned,
and the temperature (three-hour average) and charge rate (TPD), and
records for units using air pollution controls such as a wet scrubber,
dry scrubber, electrostatic precipitator, or fabric filters. The
proposed recordkeeping is intended to help ensure that small OSWI units
that choose the proposed substitute continuous compliance option are
able to demonstrate compliance with the emission and operating limits
of the OSWI standards. Among other things, the recordkeeping
requirements help to demonstrate that the waste types burned by small
OSWI units are within +/-15 percent of the percentages established for
each waste category according to the profiles established during the
initial performance test or representative performance test.
    We are also proposing reporting-related changes, especially changes
associated with the substitute compliance testing program for small
OSWI units. For example, we are proposing--for small OSWI units using
the substitute continuous compliance option--that owners and operators
would be required to include in annual reports a statement that there
were no deviations from the weekly waste characterization requirements
and the unit has been operated within the operating parameter limits.
The proposed recordkeeping and reporting is intended to help ensure
that there is adequate information available to determine compliance
with the standards and the severity of any failure to meet a standard,
and to further assure compliance with the standards at all times. We
are also proposing to clarify the timeline for submittal of an annual
report for owners and operators that choose to comply with the
substitute means of compliance in lieu of an initial performance test;
for these units, an annual report must be submitted no later than 12
months following the submission of the representative performance test
and the description of the how the test is representative for the OSWI
unit.
    We are also proposing to revise the recordkeeping and reporting
requirements for deviations, which apply to both large and small OSWI
units. Currently, these requirements focus on identifying malfunctions
and deviations from the emission limitations or operating limits that
apply, including whether any monitoring system used to determine
compliance with the emission limitations or operating limits was
inoperative, inactive, malfunctioning or out of control. We are
proposing several additional requirements to clarify that a deviation
includes any ``failure to meet an applicable standard'' and what must
be recorded and reported. The proposed changes include the following:
     Revising the definition of ``deviation'' to remove
language for periods of SSM, as discussed in section II.B.3 of this
preamble.
     Revising 40 CFR 60.2932(c) and 40 CFR 60.3033(c) to
clarify the alarm time that constitutes a deviation from the operating
limit for OSWI units with fabric filters and bag leak detection
systems.
     Revising 40 CFR 60.2932(d) and 40 CFR 60.3033(d) to
include deviations from the weekly waste characterization requirements,
provide for performance testing when the waste profile of the OSWI unit
is modified, and clarify that failure to conduct a performance test or
identify a representative test when the waste profile has changed
constitutes a deviation.
     Revising 40 CFR 60.2942(f) and 40 CFR 60.3033(f) to
clarify that, for OSWI units using CEMS, failure to collect required
data is a deviation of the monitoring requirements.
     Revising 40 CFR 60.2949 and 40 CFR 60.3046 to specify that
facilities must retain a record identifying the calendar dates, times,
and durations of malfunctions and a description of the failure and the
corrective action taken.
     Revising 40 CFR 60.2956(e) and 40 CFR 60.3051(e) to
clarify that for OSWI units with CMS, the annual report must include a
statement that there were no periods during which the CMS were

inoperative, inactive, malfunctioning or out of control.
     Removing deviation reporting requirements (40 CR
60.2956(g); 40 CFR 60.3051(g)) previously included as part of the
annual report to remove redundant reporting; these requirements are
included in the deviation report submitted on a semiannual basis (40
CFR 60.2958; 40 CFR 60.3053).
     Modifying the annual reporting requirements in 40 CFR
60.2956 and 40 CFR 60.3051 to require facilities to provide a statement
that there was no deviation identified from the weekly waste
characterization (i.e., the waste types burned are within 15-percent
variation of the profiles established during the initial performance
test) and the unit has been operated within the charge rate and
temperature ranges established when no deviations have occurred during
the reporting period.
     For deviation reporting, revising the title of 40 CFR
60.2957 and 60.3052 to ``What other reports must I submit if I have a
deviation?'', and reorganizing these sections to be consistent with the
definition of ``deviation'' and in order to better reflect the types of
deviations which must be reported.
     Clarifying the requirements of 40 CFR 60.2958 and 40 CFR
60.3053 to clarify the contents of the deviation report, including
identifying the calendar dates, times, and durations of any deviations
and a description of any corrective actions taken, and adding new
requirements to report deviations from the weekly waste
characterization and operating parameter limits established for small
OSWI units.
    We are proposing additional changes to the recordkeeping and
reporting requirements that include consistency edits based on the
proposed revisions to allow for use of CO CEMS data in lieu of annual
testing for CO (for OSWI units that have capacities greater than 10
TPD), and proposed revisions to the monitoring requirements that ensure
consistency with other CAA section 129 rules (e.g., adding operating
parameters for controls other than a wet scrubber that may be employed
for OSWI units and clarifying the frequency of the data recording or
averaging for each required operating parameter). These proposed
changes to the monitoring requirements are described further in
sections II.B.4 and II.B.8 of this preamble.
6. Proposed Requirements for Electronic Reporting
    The EPA is proposing that owners and operators of OSWI units submit
electronic copies of required performance test reports, performance
evaluation reports, deviation reports, and annual compliance reports
through the EPA's CDX using CEDRI. A description of the electronic data
submission process is provided in the memorandum, Electronic Reporting
Requirements for New Source Performance Standards (NSPS) and National
Emission Standards for Hazardous Air Pollutants (NESHAP) Rules, which
is available in the docket for this action. The proposed rule requires
that performance test results collected using test methods that are
supported by the EPA's Electronic Reporting Tool (ERT) as listed on the
ERT website \21\ at the time of the test be submitted in the format
generated through the use of the ERT, or an electronic file consistent
with the extensible markup language (XML) schema on the ERT website,
and that other performance test results be submitted in portable
document format (PDF) using the attachment module of the ERT.
Similarly, performance evaluation results of CEMS measuring relative
accuracy test audit pollutants that are supported by the ERT at the
time of the test must be submitted in the format generated through the
use of the ERT, or alternatively, an electronic file consistent with
the XML schema on the ERT website, and other performance evaluation
results, be submitted in PDF using the attachment module of the ERT.
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    \21\ https://www.epa.gov/electronic-reporting-air-emissions/electronic-reporting-tool-ert.
---------------------------------------------------------------------------

    For deviation reports and annual compliance reports, the proposed
rule requires that owners and operators use the appropriate spreadsheet
template to submit information to CEDRI. A draft version of the
proposed templates for these reports is included in the docket for this
action.\22\ The EPA specifically requests comment on the content,
layout, and overall design of the templates. Facilities would have 1
year from the date of publication of the final rule, or once the
reporting forms have been made available in CEDRI for at least 1 year,
whichever date is later, to submit these reports.
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    \22\ See OSWI_Annual_Report_Template.xlsx and
OSWI_Deviation_Report_Template.xlsx, available at Docket ID. No.
EPA-HQ-OAR-2003-015.
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    Additionally, the EPA has identified two broad circumstances in
which electronic reporting extensions may be provided. In both
circumstances, the decision to accept the claim of needing additional
time to report is within the discretion of the Administrator, and
reporting should occur as soon as possible. The EPA is providing these
potential extensions to protect owners and operators from noncompliance
in cases where they cannot successfully submit a report by the
reporting deadline for reasons outside of their control. The situation
where an extension may be warranted due to outages of the EPA's CDX or
CEDRI that preclude an owner or operator from accessing the system and
submitting required reports is addressed in 40 CFR 63.2961(d) and 40
CFR 63.3056(d). The situation where an extension may be warranted due
to a force majeure event, which is defined as an event that will be or
has been caused by circumstances beyond the control of the affected
facility, its contractors, or any entity controlled by the affected
facility that prevents an owner or operator from complying with the
requirement to submit a report electronically as required by this rule
is addressed in 40 CFR 63.2961(e) and 40 CFR 63.3056(e). Examples of
force majeure events are acts of nature, acts of war or terrorism, or
equipment failure or safety hazards beyond the control of the facility.
See proposed requirements at 40 CFR 60.2961 and 40 CFR 60.3056.
    The electronic submittal of the reports addressed in this proposed
rulemaking will increase the usefulness of the data contained in those
reports, is in keeping with current trends in data availability and
transparency, will further assist in the protection of public health
and the environment, will improve compliance by facilitating the
ability of regulated facilities to demonstrate compliance with
requirements and by facilitating the ability of delegated state, local,
tribal, and territorial air agencies and the EPA to assess and
determine compliance, and will ultimately reduce burden on regulated
facilities, delegated air agencies, and the EPA. Electronic reporting
also eliminates paper-based, manual processes, thereby saving time and
resources, simplifying data entry, eliminating redundancies, minimizing
data reporting errors, and providing data quickly and accurately to the
affected facilities, air agencies, the EPA, and the public. Moreover,
electronic reporting is consistent with the EPA's plan \23\ to
implement Executive Order 13563 and is in keeping with the EPA's
Agency-wide policy \24\ developed in response to the White House's
Digital Government

Strategy.\25\ For more information on the benefits of electronic
reporting, see the memorandum, Electronic Reporting Requirements for
New Source Performance Standards (NSPS) and National Emission Standards
for Hazardous Air Pollutants (NESHAP) Rules, referenced earlier in this
section.
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    \23\ The EPA's Final Plan for Periodic Retrospective Reviews of
Existing Regulations, August 2011. Available at: https://www.regulations.gov/document?D=EPA-HQ-OA-2011-0156-0154.
    \24\ E-Reporting Policy Statement for EPA Regulations, September
2013. Available at: https://www.epa.gov/sites/production/files/2016-03/documents/epa-ereporting-policy-statement-2013-09-30.pdf.
    \25\ Digital Government: Building a 21st Century Platform to
Better Serve the American People, May 2012. Available at: https://obamawhitehouse.archives.gov/sites/default/files/omb/egov/digital-government/digital-government.html.
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7. Proposed Revisions to Title V Permitting Requirements for ACIs
Burning Only Wood Waste, Clean Lumber, and Yard Waste
    The 2005 OSWI rule contains a regulatory requirement that ACIs that
burn only wood waste, clean lumber, and yard waste must apply for an
obtain a tile V operating permit. The EPA is proposing to eliminate
this regulatory title V permitting requirement for such ACIs that are
not located at a major source or subject to title V for other reasons.
The EPA has received feedback from several states indicating that the
title V requirements are unnecessarily burdensome and expensive for
states to maintain for these ACIs. Based on available data, ACI that
burn exclusively wood waste, clean lumber, and yard waste are commonly
located at facilities that would not otherwise require a title V
operating permit.\26\
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    \26\ CAA section 129(e) generally requires title V permits for
``solid waste incineration units.'' Under CAA section 129(g)(1),
however, the term ``solid waste incineration unit'' does not include
air curtain incinerators that only burn wood wastes, yard wastes,
and clean lumber (and that comply with opacity limitations). In
addition, in our view, the opacity limitations applicable, under CAA
129, to such ACIs are not standards or regulations ``under section
7411,'' such that the ACIs would be subject to a title V permitting
requirement under CAA section 502(a).
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    In previous rulemaking, we provided for title V permitting for
these ACIs for various reasons, as explained in the final OSWI rule (70
FR 74884-74885, Decemeber 4, 2005). In particular, we believed
initially that compliance with a title V permit was necessary to assure