[Federal Register Volume 85, Number 48 (Wednesday, March 11, 2020)]
[Rules and Regulations]
[Pages 14150-14171]
[FR Doc No: 2020-04773]

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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 82

[EPA-HQ-OAR-2017-0629; FRL-10006-10-OAR]
RIN 2060-AT81

Protection of Stratospheric Ozone: Revisions to the Refrigerant
Management Program's Extension to Substitutes

AGENCY: Environmental Protection Agency (EPA).

ACTION: Final rule.

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SUMMARY: The Clean Air Act prohibits knowingly venting or releasing
ozone-depleting and substitute refrigerants in the course of
maintaining, servicing, repairing, or disposing of appliances or
industrial process refrigeration. In 2016, the EPA amended the
regulatory refrigerant management requirements and extended
requirements that previously applied only to refrigerants containing an
ozone-depleting substance to substitute refrigerants that are subject
to the venting prohibition (i.e., those that have not been exempted
from that prohibition) such as hydrofluorocarbons. Based on changes to
the legal interpretation that supported that 2016 rule, this action
revises some of those requirements--specifically, the appliance
maintenance and leak repair provisions--so they apply only to equipment
using refrigerant containing an ozone-depleting substance.

DATES: This final rule is effective on April 10, 2020.

ADDRESSES: The EPA has established a docket for this action under
Docket ID No. EPA-HQ-OAR-2017-0629. All documents in the docket are
listed on the www.regulations.gov website. Although listed in the
index, some information is not publicly available, e.g., confidential
business information or other information whose disclosure is
restricted by statute. Certain other material, such as copyrighted
material, is not placed on the internet and will be publicly available
only in hard copy form. All other publicly available docket materials
are available electronically through www.regulations.gov.

FOR FURTHER INFORMATION CONTACT: Jeremy Arling by regular mail: U.S.
Environmental Protection Agency, Stratospheric Protection Division
(6205T), 1200 Pennsylvania Avenue NW, Washington, DC 20460; by
telephone:<PHONE_NUMBER>; or by email<EMAIL_ADDRESS>More
information can also be found at: https://www.epa.gov/section608.

SUPPLEMENTARY INFORMATION:

I. General Information

A. What is the National Recycling and Emission Reduction Program?

    Section 608 of the Clean Air Act (CAA), titled ``National Recycling
and Emission Reduction Program,'' has three main components. First,
section 608(a) requires the EPA to establish standards and requirements
regarding the use and disposal of class I and class II substances.\1\
The second component, section 608(b), requires that the regulations
issued pursuant to subsection (a) contain requirements for the safe
disposal of class I and class II substances. The third component,
section 608(c), prohibits the knowing venting, release, or disposal of
ODS refrigerants \2\ and their substitutes \3\ in the course of
maintaining, servicing, repairing, or disposing of appliances or
industrial process refrigeration (IPR). The EPA refers to this third
component as the ``venting prohibition.'' Section 608(c)(1) establishes
the venting prohibition for ODS refrigerants effective July 1, 1992,
and it includes an exemption from this prohibition for ``[d]e minimis
releases associated with good faith attempts to recapture and recycle
or safely dispose'' any such substance. Section 608(c)(2) extends
608(c)(1) to substitute refrigerants, effective November 15, 1995.
Section 608(c)(2) also includes a provision that allows the
Administrator to exempt a substitute refrigerant from the venting
prohibition if he or she determines that such venting, release, or
disposal of a substitute refrigerant ``does not pose a threat to the
environment.'' \4\
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    \1\ A class I or class II substance is an ozone-depleting
substance (ODS) listed at 40 CFR part 82, subpart A, appendix A or
appendix B, respectively. This document refers to class I and class
II substances collectively as ozone-depleting substances, or ODS.
    \2\ The term ``ODS refrigerant'' as used in this document refers
to any refrigerant or refrigerant blend in which one or more of the
components is a class I or class II substance.
    \3\ The term ``substitute'' is defined at Sec.  82.152.
    \4\ The EPA is using the term ``non-exempt substitute'' in this
document to refer to substitute refrigerants that have not been
exempted from the venting prohibition under CAA section 608(c)(2)
and Sec.  82.154(a) in the relevant end-use. Similarly, the term
``exempt substitute'' refers to a substitute refrigerant that has
been exempted from the venting prohibition under section 608(c)(2)
and Sec.  82.154(a) in the relevant end-use. A few exempt
substitutes have been exempted from the venting prohibition in all
end-uses.
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    The EPA first issued regulations under section 608 of the CAA on
May 14, 1993 (58 FR 28660, ``1993 Rule''), to establish the national
refrigerant management program for ODS refrigerants recovered during
the service, repair, or disposal of air-conditioning and refrigeration
appliances. The 1993 Rule required that persons servicing air-
conditioning and refrigeration equipment containing ODS refrigerants
observe certain practices that reduce emissions. It established

requirements for refrigerant recovery equipment, reclaimer
certification, and technician certification, and also restricted the
sale of ODS refrigerant so that only certified technicians could
purchase it. In addition, the 1993 Rule required that ODS be removed
from appliances prior to disposal, and that all air-conditioning and
refrigeration equipment using an ODS be provided with a servicing
aperture or process stub to facilitate refrigerant recovery. The 1993
Rule also established a requirement to repair leaking appliances
containing more than 50 pounds of ODS refrigerant. The rule set an
annual leak rate of 35 percent for commercial refrigeration appliances
and IPR and 15 percent for comfort cooling appliances. If the
applicable leak rate is exceeded, the appliance must be repaired within
30 days. Further, consistent with CAA section 608(c)(1), the 1993 Rule
included a regulatory provision prohibiting the knowing venting or
release of ODS refrigerant by any person maintaining, servicing,
repairing, or disposing of an appliance. (58 FR 28714; 40 CFR 82.154(a)
(1993)). It also provided that such releases would be considered de
minimis, and therefore not subject to the prohibition, if they occurred
when certain regulatory requirements were followed. (40 CFR 82.154(a)
(1993)).
    The EPA revised these regulations, which are found at 40 CFR part
82, subpart F (``subpart F''), through subsequent rulemakings published
on August 19, 1994 (59 FR 42950), November 9, 1994 (59 FR 55912),
August 8, 1995 (60 FR 40420), July 24, 2003 (68 FR 43786), March 12,
2004 (69 FR 11946), January 11, 2005 (70 FR 1972), April 13, 2005 (70
FR 19273), May 23, 2014 (79 FR 29682), April 10, 2015 (80 FR 19453),
and November 18, 2016 (81 FR 82272).
    In the April 2005 rulemaking, the EPA revised the regulatory
venting prohibition in Sec.  82.154, so that it also applied to non-
exempt substitute refrigerants, and included such substitutes in the
regulatory provision implementing the de minimis exemption, so that it
exempted ``de minimis releases associated with good faith attempts to
recycle or recover refrigerants or non-exempt substitutes'' from the
prohibition. (70 FR 19278). However, in contrast to how these
regulations applied to ODS refrigerants, they did not provide that
releases of non-exempt substitute refrigerants would be considered de
minimis if certain regulatory requirements were followed.
    Additionally, the 2004 and 2005 rules exempted certain substitute
refrigerants from the venting prohibition either in specific end uses
or in all end uses. (See 69 FR 11953-11954; 70 FR 19278; Sec.
82.154(a) (2005)). The EPA has periodically updated this list of
exemptions from the venting prohibition in the regulations at Sec.
82.154(a) since 2005. The EPA also issued proposed rules to revise the
regulations in subpart F on June 11, 1998 (63 FR 32044), elements of
which were not finalized, and on December 15, 2010 (75 FR 78558), no
elements of which were finalized. A more detailed history of these
regulatory updates can be found at 81 FR 82275.
    On November 18, 2016, the EPA published a rule updating existing
refrigerant management requirements and extending the full set of the
subpart F refrigerant management requirements, which prior to that rule
applied only to ODS refrigerants,\5\ to non-exempt substitute
refrigerants, such as hydrofluorocarbons (HFCs) and hydrofluoroolefins
(HFOs) (81 FR 82272, ``2016 Rule''). The 2016 Rule also clarified how
regulated entities could avail themselves of the de minimis exemption
for non-exempt substitutes. (See, e.g., 81 FR 82283-82285). Among the
subpart F requirements extended to non-exempt substitute refrigerants
in the 2016 Rule were provisions that restrict the servicing of
appliances and the sale of refrigerant to certified technicians,
specify the proper evacuation levels before opening an appliance,
require the use of certified refrigerant recovery and/or recycling
equipment, require that refrigerant be removed from appliances prior to
disposal, require that appliances have a servicing aperture or process
stub to facilitate refrigerant recovery, require that refrigerant
reclaimers be certified to reclaim and sell used refrigerant, and
establish standards for technician certification programs, recovery
equipment, and quality of reclaimed refrigerant. The 2016 Rule also
extended the appliance maintenance and leak repair provisions,
currently codified at Sec.  82.157, to appliances that contain 50 or
more pounds of non-exempt substitute refrigerant. For ease of
reference, in this document the EPA uses the terms ``leak repair
provisions'' or ``leak repair requirements'' interchangeably to refer
to all of the provisions at Sec.  82.157. Included in these leak repair
provisions are requirements to conduct leak rate calculations when
refrigerant is added to an appliance, repair an appliance that leaks
above the threshold leak rate applicable to that type of appliance,
conduct verification tests on repairs, conduct periodic leak
inspections on appliances that have exceeded the threshold leak rate,
report to the EPA on chronically leaking appliances, retrofit or retire
appliances that are not repaired, and maintain related documentation to
verify compliance. The regulatory changes in the 2016 Rule became
effective on January 1, 2017, but the revisions to the leak repair
provisions had a compliance date of January 1, 2019 to allow time for
the regulated community to prepare for those changes. (81 FR 82343).
The 2016 Rule additionally made numerous revisions to improve the
efficacy of the refrigerant management program as a whole, such as
revisions of regulatory provisions for increased clarity and
readability, and removal of provisions that had become obsolete.
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    \5\ The only subpart F requirements that applied to substitute
refrigerants prior to the 2016 Rule were the venting prohibition and
certain exemptions from that prohibition, as set forth in Sec.
82.154(a).
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    Two industry coalitions, the National Environmental Development
Association's Clean Air Project (NEDA/CAP) and the Air Permitting Forum
(APF), filed petitions for judicial review of the 2016 Rule in the U.S.
Court of Appeals for the District of Columbia Circuit (D.C. Circuit),
and the cases have been consolidated. (See NEDA/CAP v. EPA, No. 17-1016
(D.C. Cir. filed January 17, 2017); APF v. EPA, No. 17-1017 (D.C. Cir.
filed January 17, 2017)). The Chemours Company, Honeywell International
Inc., the Natural Resources Defense Council, and the Alliance for
Responsible Atmospheric Policy are participating as intervenor-
respondents in that litigation, in support of the 2016 Rule. In
addition, APF has filed a petition with the EPA for administrative
reconsideration of the 2016 Rule. The petition for reconsideration is
available in the docket for this action and raises several issues
regarding changes made in the 2016 Rule, such as the EPA's statutory
authority for its decision in the 2016 Rule to expand the scope of the
refrigerant management requirements--including, but not limited to,
leak repair requirements--to cover non-exempt substitute refrigerants.
Honeywell International Inc. submitted a document styled as a response
to APF's petition for reconsideration, which is also available in the
docket for this action.

B. Does this action apply to me?

    Categories and entities potentially affected by this action include
those who own or operate refrigeration and

air-conditioning appliances. Potentially affected entities include, but
are not limited to, the following:

                 Table 1--Potentially Affected Entities
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                                 North American
                                    Industry             Examples of
          Category               Classification      regulated entities
                               System (NAICS) code
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Industrial Process            111, 11251, 11511,    Owners or operators
 Refrigeration (IPR).          21111, 2211, 2212,    of refrigeration
                               2213, 311, 3121,      equipment used in
                               3221, 3222, 32311,    agriculture and
                               32411, 3251, 32512,   crop production,
                               3252, 3253, 32541,    oil and gas
                               3256, 3259, 3261,     extraction, ice
                               3262, 3324, 3328,     rinks, and the
                               33324, 33341,         manufacture of
                               33361, 3341, 3344,    frozen food, dairy
                               3345, 3346, 3364,     products, food and
                               33911, 339999.        beverages, ice,
                                                     petrochemicals,
                                                     chemicals,
                                                     machinery, medical
                                                     equipment,
                                                     plastics, paper,
                                                     and electronics.
Commercial Refrigeration....  42374, 42393, 42399,  Owners or operators
                               4242, 4244, 42459,    of refrigerated
                               42469, 42481,         warehousing and
                               42493, 4451, 4452,    storage facilities,
                               45291, 48422, 4885,   supermarkets,
                               4931, 49312, 72231.   grocery stores,
                                                     warehouse clubs,
                                                     supercenters,
                                                     convenience stores,
                                                     and refrigerated
                                                     transport.
Comfort Cooling.............  45211, 45299,         Owners or operators
                               453998, 512, 522,     of air-conditioning
                               524, 531, 5417,       equipment used in
                               551, 561, 6111,       the following:
                               6112, 6113, 61151,    Hospitals, office
                               622, 7121, 71394,     buildings, colleges
                               721, 722, 813, 92.    and universities,
                                                     metropolitan
                                                     transit
                                                     authorities, real
                                                     estate rental &
                                                     leased properties,
                                                     lodging and food
                                                     services, property
                                                     management,
                                                     schools, and public
                                                     administration or
                                                     other public
                                                     institutions.
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    This list is not intended to be exhaustive, but rather to provide a
guide for readers regarding entities likely to be affected by this
action. To determine whether your facility, company, business, or
organization could be affected by this action, you should carefully
examine the regulations at 40 CFR part 82, subpart F and the revisions
below. If you have questions regarding the applicability of this action
to a particular entity, consult the person listed in the FOR FURTHER
INFORMATION CONTACT section.

C. What action is the agency taking?

    The EPA reviewed the 2016 Rule, focusing in particular on whether
the agency had the statutory authority to extend the full set of
subpart F refrigerant management regulations to non-exempt substitute
refrigerants, such as HFCs and HFOs. Based on that review,
Administrator Pruitt signed a letter on August 10, 2017 stating that
the EPA is ``planning to issue a proposed rule to revisit aspects of
the 2016 Rule's extension of the 40 CFR part 82, subpart F refrigerant
management requirements to non-exempt substitutes.'' \6\ Consistent
with that letter, in 2018 the agency proposed to withdraw the extension
of the provisions at Sec.  82.157 to appliances using only non-exempt
substitute refrigerants.\7\ (83 FR 43922). As discussed above, these
provisions include requirements related to appliance maintenance and
leak repair. This action finalizes that proposed withdrawal and will
relieve businesses from having to repair leaks, conduct leak
inspections, and keep records for appliances containing only substitute
refrigerant.
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    \6\ Letter from the EPA to National Environmental Development
Association's Clean Air Project and the Air Permitting Forum (Aug.
10, 2017), available at www.epa.gov/sites/production/files/2017-08/documents/608_update_letter.pdf and in the docket to this rule.
    \7\ Ozone-depleting refrigerants and appliances that contain or
use any amount of ODS continue to be subject to all applicable
subpart F requirements, including those in Sec.  82.157.
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    The 2018 proposal also requested comment on whether to withdraw the
2016 Rule's extension of the full set of subpart F provisions to non-
exempt substitute refrigerants. Subpart F includes provisions that
restrict the servicing of appliances and the sale of refrigerant to
certified technicians, specify the proper evacuation levels before
opening an appliance, require the use of certified refrigerant recovery
and/or recycling equipment, require that refrigerant be removed from
appliances prior to disposal, require that appliances have a servicing
aperture or process stub to facilitate refrigerant recovery, require
that refrigerant reclaimers be certified to reclaim and sell used
refrigerant, and establish standards for technician certification
programs, recovery equipment, and quality of reclaimed refrigerant (40
CFR part 82, subpart F). In this action the EPA is not making any
changes to the subpart F provisions other than (1) limiting the
applicability of the leak repair provisions in Sec.  82.157 to
appliances that use ODS refrigerants or a blend containing ODS
refrigerants and (2) correspondingly clarifying that the reference to
Sec.  82.157 in Sec.  82.154(a)(2)(i) (the regulatory provision
implementing the de minimis exemption to the venting prohibition) only
applies for appliances that contain ODS refrigerants (including in a
blend). Consistent with the proposal, this action does not change any
of the regulatory requirements for ODS in 40 CFR part 82, subpart F.

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

    This action is based on changes to a legal interpretation of the
EPA's authority under CAA section 608 that supported the extension of
the leak repair requirements at Sec.  82.157 to non-exempt substitute
refrigerants in the 2016 Rule. As described in greater detail in
Section II below, the EPA concludes that, as a legal matter, the 2016
Rule's extension of the leak repair requirements to non-exempt
substitute refrigerants exceeded the EPA's statutory authority under
CAA section 608. Accordingly, the EPA is rescinding the 2016 Rule's
extension of the leak repair requirements to non-exempt substitutes.
However, the EPA continues to interpret section 608 as providing the
agency some authority to regulate substitutes. That includes authority
to issue regulations that interpret, explain, and enforce the venting
prohibition and the de minimis exemption under section 608(c) or that
are necessary to fulfill the purposes set forth in section 608(a)(3)
(i.e., to reduce the use and emission of ODS to the lowest achievable
level or to maximize the recapture and recycling of ODS). Because the
extension of the non-leak repair provisions in subpart F to non-exempt
substitute refrigerants remains within the scope of the EPA's authority
under 608 under the revised statutory interpretation described in this
action, the extension of those requirements is not being rescinded.

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

    Although this action is based on changes in the EPA's statutory
interpretation, the agency is providing a summary of incremental costs
and benefits associated with this action for purposes of transparency
and public information. Using a 7% discount rate, agency analyses
indicate that rescinding the extension of the leak repair provisions to
non-exempt substitutes reduces the burden associated with the 2016 Rule
by approximately $39 million per year. The EPA also estimates this rule
will increase the need to purchase non-exempt substitute refrigerant
for leaking appliances, at an overall cost of approximately $15 million
per year. Thus, incremental compliance savings and increased
refrigerant costs combined are estimated to be a reduction of at least
$24 million per year. These estimates are somewhat lower if a 3%
discount rate is used. The EPA estimates that this action will result
in forgone annual greenhouse gas (GHG) emissions reductions benefits of
about 3 million metric tons of carbon dioxide equivalent
(MMTCO2e). This rule will not result in an increase in ODS
emissions.
    Table 2 presents a summary of the annual costs, forgone emission
reductions, and benefits associated with rescinding the extension of
the leak repair provisions to non-exempt substitutes, using a 7% or a
3% discount rate, respectively.

                                       Table 2--Annual Costs and Benefits
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                                               Rescinding extension of leak repair provisions to non-exempt
                                                                        substitutes
                                         -----------------------------------------------------------------------
                                                   7% Discount rate                    3% Discount rate
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Cost Savings (Burden Reduction).........  $38,958,000.......................  $35,264,000.
Total Cost (Refrigerant Replacement)....  -$14,874,000......................  -$14,874,000.
Net Cost Savings........................  $24,084,000.......................  $20,390,000.
Forgone Emissions Reductions (non-        2.946 MMTCO2e.....................  2.946 MMTCO2e.
 monetized disbenefit).
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    Additional discussion of these analyses can be found in Section III
of this document and in the Analysis of the Economic Impact of the
Proposed 2018 Revisions to the National Recycling and Emission
Reduction Program in the docket.

II. The Final Rule

A. Legal Background and the 2016 Rule

    This action results from the EPA's decision to revisit aspects of
the 2016 Rule's extension of the 40 CFR part 82, subpart F refrigerant
management requirements to non-exempt substitutes. That process
resulted in changes to the legal interpretation supporting the 2016
Rule, which are reflected in this action. For context, we begin by
summarizing the key statutory provisions and the EPA's view of its
legal authority as presented in the 2016 Rule. The discussion of the
EPA's statutory authority to extend refrigerant management requirements
to non-exempt substitute refrigerants in the 2016 Rule focused
primarily on CAA section 608, especially on sections 608(c) and 608(a).
(See generally 81 FR 82284-82288).
    Section 608(a) requires the EPA to establish standards and
requirements regarding the use and disposal of class I and class II
substances. With regard to refrigerants, under sections 608(a)(1) and
608(a)(2), the EPA is required to promulgate regulations establishing
standards and requirements for the use and disposal of class I and
class II substances, respectively, during the service, repair, or
disposal of air-conditioning and refrigeration appliances and IPR.\8\
Section 608(a)(3) provides that regulations under section 608(a) are to
include requirements to reduce the use and emission of ODS to the
lowest achievable level, and to maximize the recapture and recycling of
such substances. Section 608(a)(3) further provides that ``[s]uch
regulations may include requirements to use alternative substances
(including substances which are not class I or class II substances) or
to minimize use of class I or class II substances, or to promote the
use of safe alternatives pursuant to section [612] or any combination
of the foregoing.'' \9\
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    \8\ We note that section 608(a) is not limited to refrigerants,
and that the EPA has applied its authority under section 608(a) to
establish or consider regulations for ODS in non-refrigerant
applications. See, e.g., 63 FR 11084.
    \9\ While section 608(a)(3) provides that the regulations issued
under section 608(a) ``may include requirements to use alternative
substances (including substances which are not class I or class II
substances), . . . or to promote the use of safe alternatives
pursuant to section [612]'', the EPA is not relying upon these
provisions in 608(a)(3) in this document, as the regulatory changes
effected by the 2016 Rule, which today's action partially rescinds,
do not relate to requirements to use substitutes or promote their
use pursuant to section 612. (In implementing Title VI, the EPA has
at times used the terms ``alternative'' and ``substitute''
interchangeably. See, e.g., 81 FR 86779, n.1; 81 FR 82276, 82291.)
Furthermore, the EPA did not rely on these authorities in 608(a)(3)
in extending the refrigerant management requirements to substitute
refrigerants in the 2016 Rule, and it is not relying on them in
addressing the underlying questions of statutory interpretation at
issue here.
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    Section 608(c) establishes a self-effectuating prohibition,
commonly called the ``venting prohibition.'' \10\ Section 608(c)(1),
effective July 1, 1992, makes it unlawful for any person, in the course
of maintaining, servicing, repairing, or disposing of an appliance or
IPR to knowingly vent, release, or dispose of any ODS used as a
refrigerant in such equipment in a manner that permits that substance
to enter the environment. Section 608(c)(1) also includes an exemption
from this prohibition for ``[d]e minimis releases associated with good
faith attempts to recapture and recycle or safely dispose'' of such a
substance. Section 608(c)(2) states that, effective November 15, 1995,
``paragraph (1) shall also apply to the venting, release, or disposal
of any substitute substance for a class I or class II substance by any
person maintaining, servicing, repairing, or disposing of an appliance
or [IPR] which contains and uses as a refrigerant any such substance,
unless the Administrator determines that venting, releasing, or
disposing of such substance does not pose a threat to the
environment.'' The EPA interprets section 608(c)(2)'s extension of
section 608(c)(1) to substitute refrigerants to extend both the
prohibition on venting and the de minimis exemption to non-exempt
substitute refrigerants. This is a long-held position which the EPA is
not revisiting in this action. (See, e.g., 69 FR 11949, March 12, 2004;
and 70 FR 19274-19275, April 13, 2005). Section 608(c) does not
expressly provide that the EPA may write regulations under that
section. Section 301, however, states that the ``Administrator is

authorized to prescribe such regulations as are necessary to carry out
his functions under [the Clean Air Act].''
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    \10\ In this context, the EPA uses the term ``self-
effectuating'' to mean that the statutory prohibition on venting is
itself legally binding even in the absence of implementing
regulations.
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    In the 2016 Rule, the EPA interpreted section 608 of the CAA as
being ambiguous with regard to the agency's authority to establish
refrigerant management regulations for non-exempt substitute
refrigerants because Congress had not precisely spoken to this issue.
Accordingly, the EPA took the view that it had the discretion under
Chevron, U.S.A., Inc. v. Natural Res. Def. Council, Inc., 467 U.S. 837,
843-44 (1984), to interpret section 608 as providing the EPA with
authority to extend all aspects of its refrigerant management
regulations under section 608 to non-exempt substitute refrigerants,
including those regulations that had previously only applied to ODS
refrigerants. (See 81 FR 82283). The 2016 Rule explained that section
608(a) expressly requires the EPA to issue regulations that apply to
class I and class II substances, but it does not expressly address
whether the EPA could establish the same refrigerant management
practices for substitute substances. On the other hand, section
608(c)(2) explicitly mentions substitute refrigerants and directly
applies the provisions for ODS refrigerants in section 608(c)(1) to
them. The 2016 Rule noted that this created a tension in the regulatory
scheme for substitute refrigerants because the regulated community is
subject to the prohibition on knowing venting, releasing, or disposing
of non-exempt substitute refrigerants while maintaining, servicing,
repairing, or disposing of air conditioning and refrigeration equipment
but at the same time section 608(a) does not direct the EPA to
promulgate regulations requiring the regulated community to recover
non-exempt substitute refrigerant prior to servicing or disposing of
such equipment or to engage in any of the practices or behaviors that
the EPA has established to minimize the emission and release of ODS
refrigerants during such maintenance, service, repair, or disposal. The
2016 Rule further explained that while the subpart F regulations made
clear that ODS refrigerant releases would be considered de minimis if
(and only if) certain regulatory requirements were followed, the rules
did not provide any such clarity regarding what practices regulated
parties must follow to qualify for the de minimis exemption, and
thereby comply with the venting prohibition, for non-exempt substitute
refrigerants. (See 81 FR 82284).
    In the 2016 Rule, the EPA grounded its authority for the extension
of refrigerant requirements to non-exempt substitute refrigerants
largely on section 608(c), which the EPA interpreted to provide it
authority to promulgate regulations that interpret, explain, and
enforce the venting prohibition and the de minimis exemption as they
apply to non-exempt substitute refrigerants. (See 81 FR 82283-82284).
In reaching this interpretation, the EPA relied in part on a policy
rationale that by establishing a comprehensive and consistent framework
that applies to both ODS and non-exempt substitute refrigerants, the
2016 Rule would provide clarity to the regulated community concerning
the measures that should be taken to comply with the venting
prohibition for non-exempt substitutes and would thus reduce confusion
and enhance compliance for both ODS and non-exempt substitutes. The EPA
further explained its view in the 2016 Rule that the extension of
requirements under section 608 to non-exempt substitutes was also
supported by section 608(a) because having a consistent regulatory
framework for non-exempt substitutes and ODS is expected to reduce
emissions of ODS refrigerants. In addition, the EPA located
supplemental authority for the 2016 Rule in section 301(a), which
provides authority for the EPA to ``prescribe such regulations as are
necessary to carry out [the EPA Administrator's] functions'' under the
Act. Id. Further, the EPA identified section 114, which provides
authority to the EPA Administrator to require recordkeeping and
reporting in carrying out provisions of the CAA, as providing
supplemental authority to extend the recordkeeping and reporting
requirements to non-exempt substitutes. Id.

B. The EPA's Reassessment of Its Legal Authority Under Section 608

    The EPA's ability to revisit existing regulations is well-grounded
in the law. Specifically, the EPA has inherent authority to reconsider,
repeal, or revise past decisions to the extent permitted by law so long
as the agency provides a reasoned explanation. See, e.g., Encino
Motorcars LLC v. Navarro, 136 S.Ct. 2117, 2125 (2016). The authority to
reconsider prior decisions exists in part because the EPA's
interpretations of statutes it administers ``[are not] instantly carved
in stone,'' but must be evaluated ``on a continuing basis.'' Chevron
U.S.A. Inc. v. NRDC, Inc., 467 U.S. 837, 863-64 (1984). This is true
when, as is the case here, review is undertaken ``in response to . . .
a change in administrations.'' National Cable & Telecommunications
Ass'n v. Brand X Internet Services, 545 U.S. 967, 981 (2005). Indeed,
``[a]gencies obviously have broad discretion to reconsider a regulation
at any time.'' Clean Air Council v. Pruitt, 862 F.3d 1, 8-9 (D.C. Cir.
2017). Similarly, the fact that an agency has previously adopted one
interpretation of a statute does not preclude it from later exercising
its discretion to change its interpretation. National Cable &
Telecommunications Ass'n, 545 U.S. at 981. In addition, an agency may
``justify its policy choice by explaining why that policy `is more
consistent with statutory language' than alternative policies.'' Encino
Motorcars, 136 S.Ct. at 2127 (quoting Long Island Care at Home Ltd. v.
Coke, 551 U.S. 158, 175 (2007)). The CAA complements the EPA's inherent
authority to reconsider prior rulemakings by providing the agency with
broad authority to prescribe regulations as necessary to carry out the
agency's functions under the CAA in section 301(a).
    In this action the agency has reassessed the 2016 Rule's assertion
of legal authority to extend the full set of subpart F requirements to
non-exempt substitute refrigerants under CAA section 608. While the
agency is retaining aspects of the interpretation that supported the
2016 Rule, it is revising that interpretation in some important
respects for greater consistency with the statutory text, structure,
and purposes, as described below. As in the 2016 Rule, the EPA
continues to interpret section 608 as being ambiguous with regard to
the agency's authority to establish refrigerant management regulations
for non-exempt substitute refrigerants. Sections 608(a)(1) and (2)
explicitly require the EPA to promulgate regulations regarding the use
and disposal of ODS but as these provisions make no mention of
substitutes they neither expressly preclude nor expressly authorize
regulation of substitutes for the purpose of achieving the ODS goals of
those provisions. Section 608(c)(2) does expressly mention substitute
refrigerants, but that provision focuses on prohibiting knowing
releases of substitute refrigerants in the course of specific
activities (maintenance, service, repair, and disposal) and on
providing an exemption for de minimis releases without specifying the
mechanisms for carrying out this prohibition and exemption. Thus,
Congress did not precisely delineate in section 608 the scope of the
EPA's authority to regulate substitute refrigerants by issuing
refrigerant management regulations.
    The EPA also continues to believe that it is reasonable to
interpret both sections 608(a) and (c) as providing authority that
could support the extension of certain subpart F

requirements to non-exempt substitute refrigerants. The EPA maintains
the position that section 608(c) is reasonably construed as providing
the agency discretionary authority to interpret, explain, and enforce
the venting prohibition and the de minimis exemption for substitute
refrigerants, as section 608(c)(2) incorporates both the prohibition
and the exemption and applies them to substitutes. Thus, these are both
elements in the statutory regime that the EPA is entrusted to
administer for substitute refrigerants. The fact that Congress extended
the de minimis exemption for ``releases associated with good faith
attempts to recapture and recycle or safely dispose of any such
substance'' to substitutes under section 608(c)(2) but did not specify
what practices or actions should be taken to qualify for this
exemption, creates a statutory ambiguity that the EPA can resolve
through regulation. However, section 608(c) is limited in the scope of
releases and activities it addresses: It specifically covers knowing
venting, release, or disposal of substitute refrigerants in the course
of maintaining, servicing, repairing, or disposing of appliances. To
the extent that the subpart F provisions extended to non-exempt
substitutes in the 2016 Rule address the potential for such releases
during one of these covered activities, those provisions continue to be
within the scope of the EPA's authority under section 608(c) under the
interpretation supporting this action.
    As for section 608(a), section 608(a)(3) requires the agency to
issue regulations that reduce the use and emission of ODS to the lowest
achievable level and maximize the recapture and recycling of such
substances. While section 608(a)(3) contains discretionary language
about what requirements those regulations may include, it does not
contain any more specific mandates about how the required objectives
should be achieved. Given this ambiguity, the EPA reasonably interprets
section 608(a) to provide authority to issue regulations that reduce
the use and emission of ODS to the lowest achievable level or that
maximize the recapture and recycling of such substances, even if the
regulations do not directly regulate ODS. Thus, as in the 2016 Rule, to
the extent that the extension of certain subpart F requirements to non-
exempt substitutes is necessary to achieve the purposes set forth in
section 608(a)(3) (i.e., reducing the use and emission of ODS to the
lowest achievable level or maximizing the recapture and recycling of
such substances), the EPA concludes that the extension is within the
ambit of its authority under section 608(a).
    In contrast to the 2016 Rule, however, the EPA has concluded that
its statutory authority under section 608, taking that authority as a
whole, does not extend as far with respect to substitutes as it does
with respect to ODS. This conclusion is supported by the text and
structure of section 608. The fact that Congress specifically included
the term ``substitutes'' in section 608(c) but not in sections
608(a)(1) or (2), contrasted with the express references to ODS (class
I and class II substances) in both subsections, suggests that the EPA's
authority to address substitutes under section 608 is more limited than
its authority to address ODS. If Congress had intended to convey
authority to the EPA to promulgate the same, full set of refrigerant
management requirements for substitutes as for ODS, it is reasonable to
expect that Congress would have expressly included substitutes in
sections 608(a)(1) or (2), as it did for section 608(c)--but it did
not. In addition, the differences in the verbs used in section 608(a)
(authorizing regulations related to the ``use and disposal'' of ODS
``including use and disposal during service, repair, or disposal'' of
appliances) compared to those used in section 608(c) (prohibiting
knowing releases ``in the course of maintaining, servicing, repairing,
or disposing'' of appliances) further supports the conclusion that
Congress envisioned that the regulations under section 608(a) would
affect a broader range of activities than those under section 608(c),
as regulations under section 608(a) could address any use or disposal
of ODS, rather than being limited to particular activities.
    In sum, while the EPA continues to interpret section 608 to provide
some authority to regulate substitute refrigerants, the EPA now reads
sections 608(a) and (c) together to determine that its authority is
more limited for substitute refrigerants than for ODS. In addition, the
EPA continues to interpret CAA section 301(a), which provides that the
EPA may ``prescribe such regulations as are necessary to carry out [the
EPA Administrator's] functions'' under the Act, to supplement its
authority to issue regulations necessary to address substitute
refrigerants under section 608(c). Further, the agency continues to
interpret CAA section 114, which provides authority to the EPA
Administrator to require recordkeeping and reporting in carrying out
provisions of the CAA, as providing supplemental authority to extend
the subpart F recordkeeping and reporting requirements to non-exempt
substitutes.

C. The EPA Lacked Authority Under Section 608 To Extend Leak Repair
Requirements To Substitute Refrigerants

    Applying the interpretive framework described in Section II.B
above, the EPA has re-examined whether the 2016 Rule's extension of the
leak repair requirements to appliances that contain only substitute
refrigerants was within its authority under section 608, either as (1)
an appropriate means of interpreting, explaining, and enforcing the
venting prohibition and the de minimis exemption under section 608(c),
or (2) as regulations that are necessary to fulfill the purposes of
section 608(a) to reduce the use and emission of ODS to the lowest
achievable level or to maximize the recapture and recycling of ODS. As
described further below, based on that legal analysis, the agency
concludes that the extension of the leak repair requirements to non-
exempt substitute refrigerants exceeded the EPA's legal authority under
section 608 because it relied on an unreasonable interpretation of that
authority. Consequently, the EPA determines that the extension of the
leak repair requirements to non-exempt substitute refrigerants must be
rescinded and is finalizing that rescission in this action. This
rescission is also consistent with the agency's view that the scope of
its authority under section 608 is more limited for substitutes than
for ODS, and the EPA today is finalizing changes to its subpart F
regulations to conform those regulations to its interpretation of the
statute.
i. Section 608(c)
    To justify the extension of the leak repair requirements to non-
exempt substitute refrigerants in the 2016 Rule, the EPA reversed its
longstanding position that ``topping off'' leaking appliances was not
knowing venting or a knowing release of refrigerant in the course of
maintaining, servicing, repairing, or disposing of an appliance within
the meaning of section 608(c). The EPA's historic position, and the one
that the agency is returning to through this action, is that
refrigerant released during the normal operation of an appliance is
generally not subject to the venting prohibition.
    When establishing the original leak repair provisions in 1993, the
EPA stated that:

    [T]he venting prohibition itself, which applies to the
maintenance, service, repair, and disposal of equipment, does not
prohibit ``topping off'' systems, which leads to emissions of
refrigerant during the use of equipment. The provision on knowing
releases does, however, include the situation in which a technician
is practically certain

that his or her conduct will cause a release of refrigerant during
the maintenance, service, repair, or disposal of equipment. Knowing
releases also include situations in which a technician closes his or
her eyes to obvious facts or fails to investigate them when aware of
facts that demand investigation. [58 FR 28672.]

    In the 2016 Rule, the EPA changed the agency's interpretation of
the venting prohibition as part of the rationale that supported
applying the leak repair requirements to non-exempt substitute
refrigerants. The EPA stated in the 2016 Rule that it:

concludes that its statements in the 1993 Rule presented an overly
narrow interpretation of the statutory venting prohibition.
Consistent with the direction articulated in the proposed 2010 Leak
Repair Rule, EPA is adopting a broader interpretation. When
refrigerant must be added to an existing appliance, other than when
originally charging the system or for a seasonal variance, the owner
or operator necessarily knows that the system has leaks. At that
point the owner or operator is required to calculate the leak rate.
If the leaks exceed the applicable leak rate for that particular
type of appliance, the owner or operator will know that absent
repairs, subsequent additions of refrigerant will be released in a
manner that will permit the refrigerant to enter the environment.
Therefore, EPA interprets section 608(c) such that if a person adds
refrigerant to an appliance that he or she knows is leaking, he or
she also violates the venting prohibition unless he or she has
complied with the applicable practices referenced in Sec.
82.154(a)(2), as revised, including the leak repair requirements, as
applicable. [81 FR 82285.] \11\
---------------------------------------------------------------------------

    \11\ The EPA did not finalize the 2010 leak repair proposal (75
FR 78558). As noted in the 2016 Rule (81 FR 82275), the EPA withdrew
the 2010 proposal in the 2016 rulemaking and re-proposed elements on
the 2010 proposal in the notice of proposed rulemaking (80 FR 69461)
for the 2016 Rule.

    The EPA now concludes that this 2016 interpretation was
unreasonable and that extending the leak repair provisions to
substitute refrigerants exceeded the scope of the agency's authority
under section 608(c)(2). The leak repair provisions include
requirements to determine whether an appliance is leaking above the
threshold leak rate applicable to that type of appliance, to repair an
appliance that leaks above the applicable leak rate, and to conduct
verification tests and periodic leak inspections on appliances that
have exceeded the threshold leak rate, as well as requirements to
retrofit or retire appliances that are not repaired and recordkeeping
and reporting requirements. The 2016 interpretation is an unreasonable
reading of section 608(c)(2) because the refrigerant releases from such
leaks typically occur during the normal operation of the appliance,
rather than ``in the course of maintaining, servicing, repairing, or
disposing of'' an appliance. The operational leaks that trigger the
leak repair provisions may take the form of a slow leak that results in
the need to add refrigerant, and such releases occur in the weeks or
months prior to the servicing event. Leaks may also result from an
unintended catastrophic failure, which leads to a subsequent service
event to recharge the appliance. Neither of these types of releases
typically occur in the course of maintaining, servicing, repairing, or
disposing of an appliance. Rather, in these situations the release of
refrigerant typically occurs before the servicing event, and the owner
or operator may not be aware of the release until it affects equipment
performance. The EPA has always understood that few appliances are
leak-free, which further supports the notion that leaks commonly occur
during the normal operation of an appliance, rather than during
appliance maintenance, service, repair, or disposal.\12\ The EPA has
also recognized that ``[t]his is particularly likely for larger and
more complicated appliances like those subject to the subpart F leak
repair provisions.'' (81 FR 82313).
---------------------------------------------------------------------------

    \12\ Recognizing that appliances can leak during their normal
operation, Sec.  82.157(g) requires periodic leak inspections of
appliances with 50 or more pounds of refrigerant that have been
repaired after leaking above the applicable threshold rate.
Automatic leak detection equipment is also allowed in lieu of
inspections for such appliances, or portions of such appliances.
---------------------------------------------------------------------------

    In addition, while the 2016 Rule cited various dictionary
definitions of the term ``maintain'' to support an interpretation that
the inclusion of the concept of maintenance in section 608(c) covered a
broad range of activities involved in preserving equipment in normal
working order (see 81 FR 82291), the EPA does not believe that Congress
intended the statutory term ``maintaining'' in section 608(c) to
include the normal operation of an appliance. Congress did use broad
language in 608(a) (``use . . . of class I and class II substances'')
that encompasses activities during normal operation of appliances. If
Congress had intended for 608(c) to apply to normal operations, it
could have included the term ``use'' in section 608(c), as it did in
section 608(a)--but it did not. In addition, the term appears in
section 608(c) as part of a group with three other terms (``servicing,
repairing, or disposing'') that are distinct from normal operation of
an appliance. Thus, reading the term in the overall context of section
608, the EPA does not believe that it is reasonable to interpret
``maintaining'' to include the normal operation of the appliance.
    The EPA is accordingly returning to the agency's reasonable
interpretation of 608(c) with respect to leaks, which had been long-
held until it was revised in the 2016 Rule. Based on this change in
interpretation, the EPA therefore concludes that the leak repair
provisions apply to activities and releases that are too distinct from
those identified in section 608(c) to provide the EPA with regulatory
authority to extend the leak repair regulations to non-exempt
substitute refrigerants.\13\
---------------------------------------------------------------------------

    \13\ Furthermore, the leak repair provisions are not
sufficiently related to ``good faith attempts to recapture and
recycle or safely dispose'' of refrigerant under the de minimis
exemption in section 608(c) for that provision to provide
independent authority for the extension of the leak repair
requirements to non-exempt substitute refrigerants.
---------------------------------------------------------------------------

    The EPA notes that under this interpretation the venting
prohibition under section 608(c) would continue to apply to actions
taken in the course of maintaining, servicing, repairing, or disposing
of appliances containing non-exempt substitute refrigerant, including
those containing 50 or more pounds of such refrigerant. For example,
knowing release from cutting refrigerant lines when disposing of an
appliance is prohibited. Similarly, opening an appliance to repair a
component without first isolating it and recovering the refrigerant
would typically lead to a knowing release of refrigerant to the
environment during the service, maintenance, or repair of an appliance
and thus would also be prohibited. It is also possible that some
``topping off'' may occur in an appliance with a leak that is so
visible, audible, or frequent that adding refrigerant to the appliance
creates the practical certainty that the refrigerant will be released
contemporaneously with the servicing event to add refrigerant and
therefore may constitute a knowing release subject to the venting
prohibition. For example, hearing hissing or noticing a ruptured line
while continuing to add refrigerant to an appliance would constitute a
knowing release. However, the EPA has no information to suggest that
this occurs in a substantial number of situations, and the mere
possibility of such an event does not justify a blanket interpretation
that ``topping off'' an appliance that has leaked, absent adherence to
the requirements at Sec.  82.157, is necessarily and per se a violation
of 608(c).

ii. Section 608(a)
    The EPA stated in the preamble to the 2016 Rule that the agency's
authority for extending the refrigerant management regulations to
substitute refrigerants is based in part on section 608(a), in light of
the corresponding reductions in ODS emissions and increases in ODS
recapture and recycling that are expected to result from requiring
consistent practices for ODS and substitute refrigerants. (81 FR
82288). In part, this was based on the potential for cross-
contamination, refrigerant mixing, and related releases from ODS
appliances in the absence of consistent practices. The response to
comments for the 2016 Rule \14\ also noted, in the context of
explaining the EPA's authority for the revisions to Sec.  82.157, that
providing a consistent standard for ODS and non-exempt substitute
refrigerants would reduce emissions of ODS by reducing the incidence of
failure to follow the requirements for ODS appliances due to
refrigerant confusion. However, in neither discussion did the EPA
address whether, if all other subpart F requirements were extended to
non-exempt substitutes, it would be necessary to also extend Sec.
82.157 to non-exempt substitute refrigerants to serve the purposes of
section 608(a), as articulated in sections 608(a)(3)(A) and (B).
---------------------------------------------------------------------------

    \14\ Response to Comments for the Notice of Proposed Rulemaking:
Protection of Stratospheric Ozone: Update to the Refrigerant
Management Requirements under the Clean Air Act, pages 13-14 (pdf
pages 18-19). Available at: https://www.regulations.gov/document?D=EPA-HQ-OAR-2015-0453-0226.
---------------------------------------------------------------------------

    After further consideration, the EPA believes that these statements
in the 2016 Rule, which were advanced generally and without distinction
to support extending all the subpart F requirements to non-exempt
substitute refrigerants, failed to recognize that the leak repair
provisions have a more attenuated connection to the purposes of section
608(a) when applied to non-exempt substitute refrigerants than do the
rest of the subpart F requirements, especially once application of all
the other subpart F requirements to such refrigerants is taken into
account. After further consideration, the EPA believes that extending
the leak repair requirements to appliances containing non-exempt
substitutes is not necessary to meet the purposes of section 608(a).
Because the EPA is retaining the other subpart F requirements for non-
exempt substitute refrigerants, the rescission of the extension only of
the leak repair requirements is unlikely to directly affect ODS
emissions or the recapture and recycling of ODS. For example, since the
EPA is retaining the requirement that only a certified technician can
open an appliance containing non-exempt substitute refrigerant, it is
unlikely that leaks in appliances with 50 or more pounds of ODS
refrigerant would not be repaired because of a difference in the duty
to repair between appliances containing ODS and those containing
substitute refrigerants. The repair of leaks in ODS-containing
appliances in this size range has been required since 1993, and owners
and operators of such appliances as well as certified technicians are
well aware of those requirements.
    The EPA also does not believe that applying the leak repair
provisions to appliances that use only non-exempt substitute
refrigerants would independently reduce cross-contamination,
refrigerant mixing, or related releases from an ODS appliance. As
discussed further in Section II.D of this document, the agency will
continue to apply the other elements of the 608 program, such as the
refrigerant sales restriction, technician certification, reclamation
requirements, and evacuation standards, to non-exempt substitute
refrigerants, and these elements address those concerns. Taken
together, the other subpart F requirements also reduce the incidence of
failure to follow the requirements for ODS appliances. By contrast,
application specifically of the leak repair requirements to equipment
containing only substitute refrigerants would not lead to additional
reductions in ODS emissions. Nor would it lead to additional increases
in the recapture and recycling of ODS because there is no ODS in these
appliances to be recaptured or recycled.
    Thus, insofar as the 2016 Rule was grounded in an argument that
section 608(a) supports the extension of the leak repair provisions to
non-exempt substitute refrigerants, the EPA is withdrawing that
interpretation. Accordingly, the EPA concludes that the connection
between applying the leak repair requirements to appliances with only
substitute refrigerants and serving the purposes in section 608(a)(3)
is too tenuous to reasonably support reliance on CAA section 608(a) as
a basis for authority to extend the leak repair requirements to non-
exempt substitutes.

D. The EPA Had Authority Under Section 608 To Extend Subpart F
Provisions Other Than Leak Repair Provisions To Substitute Refrigerants

    The EPA requested comments on whether the agency should withdraw
the entire extension of subpart F requirements to non-exempt substitute
refrigerants in the 2016 Rule given its proposed interpretation. As
described in more detail below, after considering the comments
received, and analyzing the relevant provisions under the interpretive
framework described in Section II.B above, the EPA concludes that,
except for the leak repair provisions, the 2016 Rule's extension of the
subpart F requirements to non-exempt substitute refrigerants was within
the scope of its authority under section 608. Thus, aside from the
rescission of the extension of the leak repair provisions discussed in
Section II.C, the EPA is not withdrawing the extension of any of the
non-leak repair provisions in subpart F to non-exempt substitute
refrigerants.
i. Section 608(c)
    The EPA is retaining the extension of the non-leak repair
provisions in subpart F for non-exempt substitute refrigerants as
appropriate measures to interpret, explain, and enforce the venting
prohibition and the de minimis exemption for non-exempt substitute
refrigerants under 608(c). In contrast to the leak repair requirements,
the other provisions of subpart F that the EPA extended to non-exempt
substitute refrigerants in the 2016 Rule relate directly to releases
that necessarily occur in the course of maintaining, servicing,
repairing, or disposing of an appliance. Accordingly, those provisions
directly address the potential for knowing releases of non-exempt
substitute refrigerants that would be within the scope of section
608(c)(2) or the application of the de minimis exemption to non-exempt
substitute refrigerants under section 608(c)(2), and therefore are
within the EPA's authority under section 608(c)(2).
    The EPA has long recognized connections between the non-leak repair
requirements in subpart F and the potential for releases to occur
during appliance maintenance, service, repair, or disposal, and
continues to do so. For example, failure to properly evacuate an
appliance (Sec.  82.156 and Sec.  82.158) before opening it for
servicing will create the practical certainty that the refrigerant in
the appliance will be released during the servicing event. The
requirement that small appliances be equipped with a process stub
(Sec.  82.154(e)(2)) facilitates the removal of refrigerant at
servicing and disposal. The requirements (Sec. Sec.  82.156 and 82.158)
that recovery and/or recycling equipment be used during the
maintenance, servicing, repair or disposal of an appliance, and that
such equipment be tested and

certified by an EPA-approved laboratory or organization, are intended
``to ensure that recycling and recovery equipment on the market is
capable of limiting emissions'' during such servicing and disposal
activities. (58 FR 28682). The vapor recovery efficiency and the
efficiency of noncondensable purge devices on recycling machines affect
total recovery efficiency and thus how much refrigerant will be
released to the environment once the appliance is opened for
maintenance, servicing, repair or disposal. After a certified
technician properly evacuates an appliance according to the
requirements of Sec.  82.156, any remaining refrigerant that is then
released during the maintenance, service, repair or disposal of the
appliance can be considered a de minimis release associated with good
faith attempts to recycle or recover refrigerants. Similarly, disposing
of an appliance without removing the refrigerant as required under
Sec.  82.155 will result in the release of any remaining refrigerant
during disposal of the appliance. The EPA has long emphasized this
point. When the EPA first issued the safe disposal requirements in
1993, the EPA stated: ``The Agency wishes to clarify that the
prohibition on venting refrigerant includes individuals who are
preparing to dispose of a used appliance.'' (58 FR 28703). The
recordkeeping provisions at Sec.  82.155(c)(2) are necessary to ensure
that disposers of small appliances are adhering to the venting
prohibition and the evacuation requirements. Similarly, the
recordkeeping provisions at Sec.  82.156(a)(3) ensure that technicians
are adhering to the venting prohibition and evacuation requirements
when disposing of mid-sized appliances. These recordkeeping
requirements help ensure accountability for compliance with the venting
prohibition, as well as improving the enforceability of the
prohibition. With respect to the sales restriction and technician
certification requirements, consistent with its long-standing view, the
EPA continues to believe that ``unrestricted sales will enable
untrained or undertrained technicians to obtain access to refrigerants
that are likely to be used improperly in connection with servicing
activities that will result in the venting of refrigerants'' (58 FR
28698) and that restricting servicing activities to technicians trained
on the regulatory requirements and proper use of equipment reduces
emissions and enhances compliance (see 58 FR 28692). Further,
``[e]ducating technicians on how to contain and conserve refrigerant
effectively, curtailing illegal venting into the atmosphere'' was one
of the primary reasons many technicians commented in support of the
certification program when it was initially promulgated. (58 FR 28691).
    Thus, the EPA continues to agree with the assessment in the 2016
Rule that these refrigerant management provisions address releases that
necessarily occur in the course of maintaining, servicing, repairing,
or disposing of an appliance. Accordingly, the agency concludes that
the 2016 Rule's extension of these subpart F requirements to non-exempt
substitute refrigerants is within the scope of the EPA's authority
under CAA section 608(c)(2), because these requirements interpret,
explain, or help enforce that provision's venting prohibition and the
application of the de minimis exemption.
    The EPA views the agency's authority to extend the reclamation
requirements to non-exempt substitute refrigerants under section 608(c)
as relating specifically to appliance servicing and disposal. By
``reclamation requirements,'' the EPA means: The requirements under
Sec.  82.164, including the requirements to reclaim used refrigerant
before it is sold for use in an appliance; the requirement that
reclaimed refrigerant be tested and meet AHRI Standard 700-2016,
Specifications for Refrigerants (an industry developed consensus
standard that the EPA has adopted into its regulations); and the
requirement that reclaimers be certified by the EPA and agree to meet
certain standards. The EPA interprets section 608(c), particularly the
provisions relating to the servicing and disposal of appliances as
described below, to provide authority that supports the extension of
the reclamation requirements to non-exempt substitute refrigerants.
    Section 608(c)(1) states that ``it shall be unlawful for any person
in the course of maintaining, servicing, repairing, or disposing of an
appliance . . . to knowingly vent or otherwise knowingly release or
dispose of any class I or class II substance used as a refrigerant . .
. in a manner which permits such substance to enter the environment.''
Furthermore, the de minimis exemption encompasses ``releases associated
with good faith attempts to recapture and recycle or safely dispose of
any such substance . . .'' As described above, the EPA interprets
section 608(c)(2) to extend the prohibitions in 608(c)(1), including
the restriction on releases in the course of disposing and servicing of
appliances and the de minimis exemption, to substitute substances.
    As part of the EPA's authority to interpret, explain, and enforce
the venting prohibition under 608(c), the agency also has authority to
address what constitutes disposal of an appliance. The agency defines
``disposal'' in Subpart F to mean ``the process leading to and
including'' several listed activities, such as ``the discharge,
deposit, dumping or placing of any discarded appliance into or on any
land or water;'' the ``disassembly of any appliance for discharge,
deposit, dumping or placing of its discarded component parts into or on
any land or water'' or for reuse of its component parts; the
``vandalism of any appliance such that the refrigerant is released into
the environment or would be released into the environment if it had not
been recovered prior to the destructive activity;'' and the ``recycling
of any appliance for scrap.'' (Sec.  82.152).
    The reclamation requirements explain how to ``recapture and
recycle'' refrigerants that are recovered in the course of servicing or
disposing of an appliance in lieu of releasing them into the
environment. Reclamation, a process whereby used refrigerant is
purified to meet required specifications and then permitted to be sold
for reuse, is a means of ``recaptur[ing] and recycl[ing]'' refrigerant.
The reclamation requirements have the added benefit of supporting a
market in which technicians can sell recovered refrigerant to
reclaimers for compensation; this provides a financial benefit to
technicians who recover refrigerant during appliance disposal rather
than venting it.\15\
---------------------------------------------------------------------------

    \15\ Much of the refrigerant recovered and sent for reclamation
occurs during the disposal of an appliance. However, some
refrigerant that is sent for reclamation is also recovered during
the servicing of an appliance, including the retrofitting of an
appliance for use with a different refrigerant.
---------------------------------------------------------------------------

    The interpretation that the reclamation requirements directly
relate to interpreting, explaining, and enforcing the prohibition on
venting during appliance servicing and disposal is further supported by
the fact that Congress included ``releases associated with good faith
attempts to . . . recycle or safely dispose of any such substance'' in
the de minimis exemption to the venting prohibition. This indicates
that Congress clearly contemplated that certain refrigerant-related
actions could be implicated by the appliance-related actions covered by
the venting prohibition.
    The EPA further interprets the phrase ``recycle or safely dispose
of any such substance,'' when referring to either ODS or non-exempt
substitute refrigerants, to include reclamation. Accordingly, the EPA
believes the extension of the reclamation

requirements to non-exempt substitutes refrigerants is supported by
608(c) because these requirements interpret, explain, and enforce
section 608(c)'s prohibition on releases of non-exempt substitute
refrigerants during the servicing and disposal of appliances and the de
minimis exemption for recycling or safely disposing of such
refrigerants.
ii. Section 608(a)
    The EPA also concludes that section 608(a) provides the EPA
authority for the 2016 Rule's extension of the non-leak repair subpart
F requirements to the extent that there is demonstrably a connection
between those requirements and the purposes of 608(a), as articulated
in sections 608(a)(3)(A) and (B). As the EPA concluded in the preamble
to the 2016 Rule:

    This action extending the regulations under subpart F to non-
exempt substitutes is additionally supported by the authority in
section 608(a) because regulations that minimize the release and
maximize the recapture and recovery of non-exempt substitutes will
also reduce the release and increase the recovery of ozone-depleting
substances. Improper handling of substitute refrigerants is likely
to contaminate appliances and recovery cylinders with mixtures of
ODS and non-ODS substitutes, which can lead to illegal venting
because such mixtures are difficult or expensive to reclaim or
appropriately dispose of. . . . In short, the authority to
promulgate regulations regarding the use of class I and II
substances encompasses the authority to establish regulations
regarding the proper handling of substitutes where this is needed to
reduce emissions and maximize recapture and recycling of class I and
II substances. Applying consistent requirements to all non-exempt
refrigerants will reduce complexity and increase clarity for the
regulated community and promote compliance with those requirements
for ODS refrigerants, as well as their substitutes. [81 FR 82286.]

    The 2016 Rule discussed how failure to apply consistent standards
to appliances containing non-exempt substitute refrigerants and those
containing ODS refrigerants could lead to emissions of ODS (81 FR
82288). After additional consideration, the EPA affirms the potential
for such inconsistent requirements to increase ODS emissions. For
example, applying the sales restriction and technician certification
requirements for persons servicing appliances using non-exempt
substitute refrigerants reduces the possibility that refrigerant in the
appliances may be misidentified or mishandled by an uncertified person
attempting to service the appliance. Improper handling of non-exempt
substitute refrigerants by persons lacking the requisite training may
contaminate appliances and recovery cylinders with mixtures of ODS and
non-ODS substitutes. Contaminated appliances may lead to equipment
failures and emissions from those systems, including emissions of ODS.
Contaminated refrigerant is more costly to reclaim for re-use and the
only other option besides reclamation (or recycling for use by the same
owner) to avoid its entry to the environment is that it be destroyed.
However, the costs of reclaiming or destroying these mixed refrigerants
incentivizes intentional releases, including of ODS, to the atmosphere
from contaminated appliances and recovery cylinders. Applying the same
requirements for servicing and disposing of appliances containing ODS
and non-exempt substitute refrigerant ensures standard procedures are
followed, which reduces the possibility for errors and the risk of ODS
emissions associated with misidentification or mishandling of the
refrigerant.
    The EPA also concludes that section 608(a) provides the EPA
authority for the 2016 Rule's extension of the reclamation requirements
to non-exempt substitute refrigerants. The EPA established the
reclamation requirement for used ODS refrigerant in 1993 to prevent
equipment damage, and the resultant emissions caused by use of
contaminated refrigerant in appliances, and to provide confidence in
the market for used refrigerants (58 FR 28678). Because of the venting
prohibition, combined with the phaseout of ODS, the EPA in 1993
anticipated a large increase in recovered refrigerant and was concerned
about the risks to appliances posed by use of contaminated refrigerant.
As the EPA stated in the 1993 Rule, damaged equipment would often leak
during operation and would require servicing or replacement more often
than undamaged equipment, increasing refrigerant emissions. Damage to
equipment would also reduce consumer confidence in the quality of used
refrigerant, leading to erosion of the market for used refrigerants and
possibly to their release. As described further below, the 2016 Rule's
extension of the reclamation requirements to non-exempt substitute
refrigerants addresses these concerns and therefore furthers the goals
of section 608(a)(3) to reduce the emissions of ODS and maximize the
recapture and recycling of ODS.
    An important aspect of the reclamation requirements is the
requirement that used refrigerant be reclaimed to certain purity
standards prior to sale for re-use. By requiring that used refrigerant
be reclaimed prior to sale, the reclamation requirements also prohibit
the immediate reuse of recovered refrigerant, with the exception of use
in equipment owned by the same entity owning the equipment from which
the refrigerant was removed. In 1993, the EPA expressed concern that
recovered refrigerant may contain moisture, acids, oil, particulates,
or other contaminants that can lead to serious damage to the equipment
if it is reused without taking some action to remove these
contaminants. Recovered non-exempt substitute refrigerants today
contain those same contaminants as in 1993 with one significant
difference: The increase in the use of substitute refrigerants,
including multi-component blends, has resulted in more types of
refrigerant encountered by technicians. Often ODS and non-ODS
refrigerants are improperly recovered into the same recovery cylinder,
leading to mixed refrigerant which contains both ODS and non-ODS. This
is supported by data reported annually by EPA-certified reclaimers
under Sec.  82.164(d)(3) which show that the amount of mixed
refrigerant they receive is increasing.\16\ The lack of consistent
reclamation requirements for non-exempt substitutes could result in
confusion about what to do if there is uncertainty about the contents
of a cylinder or about the proper treatment of mixtures. Equipment can
be damaged, resulting in refrigerant emissions, including ODS
emissions, if such mixed refrigerant is not sent for reclamation but
rather sold and recharged into appliances designed for non-exempt
substitute refrigerants. Reclamation requirements to remove impurities
and separate mixed refrigerants reduce the likelihood of equipment
failure and subsequent emissions of ODS. These requirements also
promote the recycling of ODS because once it is separated from the
mixed refrigerant the ODS can subsequently be reclaimed for reuse.
---------------------------------------------------------------------------

    \16\ These data can be found at: https://www.epa.gov/section608/summary-refrigerant-reclamation-trends.
---------------------------------------------------------------------------

    In addition, the combined effect of the reclamation provisions
relating to EPA's certification of reclaimers, the purity standards
that reclaimed refrigerant must meet, and the testing of that
refrigerant to ensure it meets those standards together provide
confidence in the market for used refrigerants. Reclamation is
performed by private businesses and is subject to market forces.
Currently these market forces provide a financial incentive to
technicians to recover refrigerant and send it to a reclaimer in as
pure a state as possible to maximize the

compensation they receive. Absent that financial incentive, technicians
may be more likely to vent the refrigerant than to send it for
reclamation, which could lead to ODS emissions when the refrigerant
vented is an ODS or a mixture containing ODS. These market forces also
sustain an industry whose function is to reprocess used refrigerant.
Reclamation is critical to achieving the goal of maximizing the
recapture and recycling of ODS, as set forth in section 608(a)(3)(B).
Absent reclamation, banks of ODS refrigerant found in existing
equipment, in stockpiles, or mixed with other used refrigerant will
instead likely be released, given the costs of destruction. In sum, the
EPA concludes that the extension of the reclamation requirements to
non-exempt substitutes is supported by section 608(a)(3) because
extending these requirements to non-exempt substitutes serves the
purposes set forth in 608(a)(3) of maximizing the recapture and
recycling of ODS and reducing ODS emissions to the lowest achievable
level.
    In conclusion, because the application of the non-leak repair
requirements to non-exempt substitute refrigerants is connected to the
purposes of section 608(a)(3) via the corresponding reductions in ODS
emissions and increases in ODS recapture and recycling that are
expected to result from maintaining the reclamation requirements for
non-exempt substitute refrigerants and retaining consistent practices
for ODS and non-exempt substitute refrigerants. Therefore, the EPA
concludes that the extension of these requirements is within the scope
of its authority under CAA 608(a).

III. Summary and Response to Major Comments

    This section summarizes many comments received on this rule,
particularly those related to the EPA's legal authority to regulate
substitute refrigerants under section 608, and the EPA's responses.
Other comments received for this action are addressed in Sections IV
and V below, as well as in the response to comments document found in
the docket for this action.

A. Comments on the Scope of the Agency's Authority To Regulate
Substitutes Under Section 608(c)

    The EPA received multiple comments in support of the agency's
authority to interpret and explain section 608(c) through the issuance
of regulations. These commenters point to the text, purpose, context,
and legislative history of section 608(c) to argue that the EPA has
broad authority to regulate substitute refrigerants to prevent illegal
venting. Most of these commenters support the EPA's view of its
authority as articulated in the 2016 Rule, both for the leak repair
provisions and the non-leak repair provisions in subpart F. Other
commenters, however, state that the EPA's authority under 608(c) does
not allow for the leak repair provisions established in the 2016 Rule.
One of those commenters states that the EPA has authority to establish
the non-leak repair requirements for substitutes, but not the leak
repair provisions. Another one of those commenters states that the
EPA's authority under 608(c) does not extend so far as to authorize
regulations for substitutes that are co-extensive with the regulations
required under 608(a) requirements for ODS. That commenter states that
the lack of an explicit grant of authority from Congress for the EPA to
establish a regulatory program for substitutes indicates that no such
authority exists, arguing that Congressional silence is not a
delegation of authority to regulate. Another commenter states that the
EPA lacks authority to regulate substitutes in any manner under section
608(c). The commenter states that 608(c) is a self-effectuating
enforceable requirement to use good management practices and does not
provide the EPA with the authority to implement a regulatory program.
    The agency agrees that the EPA's authority to issue regulations
interpreting, explaining, and enforcing section 608(c) is not co-
extensive with its authority to regulate under section 608(a). Thus,
the agency disagrees with the comments that supported the view of the
EPA's authority as articulated in the 2016 Rule. As explained in
Section II above, the agency now interprets sections 608(a) and (c)
together to determine that while these provisions are reasonably read
to provide it some authority to regulate substitute refrigerants, its
authority is more limited for substitute refrigerants than for ODS. In
so doing, the EPA recognizes and gives weight to the fact that sections
608(a) and 608(c) differ from one another in some key respects,
including the fact that 608(a)(1) and (2) expressly require the EPA to
issue regulations for class I and class II substances, but include no
such requirement for--or indeed any mention of--substitutes. In
contrast, 608(c) does explicitly apply to substitute refrigerants, but
that subsection leaves the EPA discretion as to whether to promulgate
regulations implementing its provisions and is focused on preventing
knowing releases of refrigerants in the course of maintaining,
servicing, repairing, or disposing of appliances and on providing an
exemption for de minimis releases without specifying the mechanisms for
carrying out this prohibition and exemption. In light of these
differences in wording between 608(a) and 608(c), the EPA concludes in
this action that the 2016 Rule's extension of the full set of subpart F
requirements to non-exempt substitute refrigerants exceeded its
statutory authority under section 608 because the extension of the full
set of requirements (i.e., as an entirety) was inconsistent with the
more limited scope of the EPA's authority under section 608 to regulate
substitute refrigerants as compared with its authority to regulate ODS
refrigerants. In addition, as explained in Section II of this document,
the EPA has concluded that the 2016 Rule's extension of the leak repair
requirements to non-exempt substitute refrigerants exceeded its
authority under both sections 608(c) and 608(a). Therefore, the agency
disagrees with the comments concluding that the EPA did have authority
to extend the leak repair requirements to non-exempt substitute
refrigerants, and agrees with the comments that the extension of these
requirements exceed the agency's authority under 608(c).
    To the extent that the comments are intended to suggest that any
overlap between regulations under sections 608(a) and 608(c) exceeds
the EPA's statutory authority, the agency disagrees. The fact that
Congress required the EPA to address ODS refrigerants in a specific way
under section 608(a), and then included a separate provision under
608(c) to address knowing venting, release, and disposal of ODS and
substitute refrigerants during certain activities, does not demonstrate
that Congress intended to preclude the EPA from implementing section
608(a) and the venting prohibition in section 608(c) by using similar
requirements for ODS and substitute refrigerants, when such an approach
is independently consistent with those statutory provisions. Taking
such an approach does not mean that the agency is using section 608(a)
to implement section 608(c), or vice versa, but instead simply
indicates that these regulatory approaches can be justified under both
section 608(a) and 608(c).\17\

For example, as explained in Section II above, the EPA concludes it was
within its statutory authority under both sections 608(a) and 608(c) to
extend the non-leak repair provisions in subpart F to substitute
refrigerants.
---------------------------------------------------------------------------

    \17\ As explained in the 2016 Rule, the EPA continues to believe
that using section 608(c) to establish similar requirements to those
authorized under section 608(a) does not render section 608(a) a
nullity: ``Unlike section 608(c), section 608(a) is not limited to
refrigerants. EPA has applied its authority under section 608(a) to
establish or consider regulations for ODS in non-refrigerant
applications. As an example, in 1998, EPA issued a rule on halon
management under the authority of section 608(a)(2) (63 FR 11084,
March 5, 1998). In that action, EPA noted that section 608(a)(2)
`directs EPA to establish standards and requirements regarding the
use and disposal of class I and II substances other than
refrigerants.' 63 FR 11085. Similarly, EPA considered whether to
establish a requirement to use gas impermeable tarps to reduce
emissions of methyl bromide under section 608(a)(2), ultimately
determining not to do so for technological and economic reasons. 63
FR 6008 (February 5, 1998).'' (82 FR 82290).
---------------------------------------------------------------------------

    With regard to the comments that the EPA does not have regulatory
authority under section 608(c) either because that provision is self-
effectuating or because it does not contain explicit authorization to
issue regulations, the EPA disagrees. The agency has long held and
continues to maintain that 608(c), though self-effectuating, provides
authority to issue implementing regulations that interpret, explain,
and enforce the venting prohibition and the de minimis exemption in
section 608(c) and that include the venting prohibition in the overall
context of the regulatory scheme. (See, e.g., 69 FR 11947). Thus, while
section 608(c) does not include a requirement to issue regulations as
section 608(a) does, the agency does not view the lack of a requirement
as equivalent to a prohibition on issuing regulations under section
608(c). This is not a situation where Congress was silent as to whether
the statutory provision applies to substitutes. Rather, Congress
specifically included substitutes in the venting prohibition. It also
provided the agency additional discretion to exempt substitutes from
the venting prohibition when it determined that the venting, release,
or disposal of the substitute did not pose a threat to the environment.
The EPA construes the inclusion of substitutes in section 608(c)(2) in
these ways to indicate that Congress contemplated that regulation of
substitutes would occur. Furthermore, while the EPA is not relying on
CAA section 301(a) for primary or substantive authority in this action,
the agency believes that the text of CAA section 301(a), which provides
that the EPA may ``prescribe such regulations as are necessary to carry
out [the EPA Administrator's] functions'' under the Act, supplements
its authority under section 608(c) to issue regulations that interpret,
explain, or enforce the venting prohibition and the de minimis
exemption. In addition, as some commenters point out, the legislative
history indicates that in establishing the venting prohibition,
Congress expected the EPA to promulgate regulatory ``provisions to
foster implementation of this prohibition, including guidance on what
constitutes `de minimis' and `good faith'.'' Report of the Committee on
Environment and Public Works United States Senate, Report Accompanying
S. 1630 (S. Rept. 101-228) (December 20, 1989) at 396 (reprinted in 5 A
Legislative History of the Clean Air Act Amendments of 1990, at 8736
(1993)).
    Furthermore, as explained in Section II of this document, the
agency continues to view section 608 as ambiguous in important
respects. In section 608(c) Congress provided an exemption to the
venting prohibition for certain de minimis releases, but it did not
define what releases would be considered ``de minimis'' nor which
activities would be considered ``good faith attempts to recapture and
recycle or safely dispose'' of such substances. Where Congress has not
directly spoken to an issue or has left ambiguity in the statute, that
silence or ambiguity creates an assumption that ``Congress implicitly
delegated to the agency the power to make policy choices that represent
a reasonable accommodation of conflicting policies that are committed
to the agency's care by the statute.'' National Ass'n of Mfrs. v.
United States DOI, 134 F.3d 1095, 1106 (D.C. Cir. 1998). As the U.S.
Supreme Court has explained, the ``power of an administrative agency to
administer a congressionally created . . . program necessarily requires
the formulation of policy and the making of rules to fill any gap left,
implicitly or explicitly, by Congress.'' Chevron, 467 U.S. at 843-44.
Accordingly, Congress's silence with regard to carrying out the venting
prohibition and the exception for certain releases leaves a gap for the
Agency to fill.
    Consistent with this view, the EPA's regulations at Sec.  82.154
have included the venting prohibition since they were originally
promulgated in 1993. (58 FR 28714). Even before the 2016 Rule, the
subpart F regulations provided that ``[n]o person maintaining,
servicing, repairing, or disposing of appliances may knowingly vent or
otherwise release into the environment any refrigerant or substitute
from such appliances'' and then provided for exceptions from this
prohibition for specified substitutes in specified end-uses. (Sec.
82.154 (2014)). These exceptions implemented the discretion Congress
left the EPA under 608(c)(2) to exempt certain releases from the
venting prohibition, if the Administrator has determined that
``venting, releasing, or disposing of such substance does not pose a
threat to the environment.'' CAA section 608(c)(2). Similarly, the
regulations at Sec.  82.154 in place before the 2016 Rule included
provisions clarifying that ``[ODS] releases shall be considered de
minimis only if they occur when'' certain regulatory requirements are
observed. (Sec.  82.154(a)(2) (2014)). However, those regulations did
not provide the same clarity regarding releases of non-exempt
substitute refrigerants or what practices would be considered to fall
within the ambit of ``good faith attempts to recycle or recover'' non-
exempt substitute refrigerants. (Sec.  82.154(a)(2)). The EPA has long
interpreted section 608(c)(2) to incorporate and extend both the
venting prohibition and the de minimis exemption in section 608(c)(1)
to substitute refrigerants, but Congress did not specify what practices
or actions should be taken to qualify for this exemption in either
provision. Thus, it is reasonable to interpret these provisions as
indicating that Congress contemplated that the EPA would have authority
to resolve this ambiguity by issuing regulations to implement section
608(c). For these reasons, and as explained in prior sections of this
document, the EPA continues to believe that section 608(c) is
reasonably interpreted to provide it some authority to issue
regulations applicable to substitute refrigerants and thus disagrees
with these comments.

B. Comments on Whether ``Topping Off'' a Leaking Appliance Constitutes
a Knowing Release Subject to the Venting Prohibition

    The EPA received multiple comments stating that the operation of an
appliance, and the ``topping off'' with additional refrigerant, is not
knowing venting prohibited under section 608(c). They state that
venting must occur during the service, maintenance, repair, or disposal
of an appliance to be prohibited. Other comments disagree with the
EPA's proposed decision to return to its pre-2016 interpretation of
``topping off.'' A couple of commenters state that the fact that
refrigerant must be added demonstrates that there is a leak, which
would continue if not repaired, and that a technician that repeatedly
tops off refrigerant from leaking equipment knows the refrigerant is
being released. These commenters object to the proposal to return to
the prior interpretation of ``topping off'' because under that
interpretation, no matter how significant the quantity of lost
refrigerant from a leaking appliance, it would not violate the venting
prohibition unless there was a practical

certainty refrigerant was being released during the servicing event.
These commenters thought such a result conflicted with section 608's
purpose of reducing emissions of ODS and their substitutes. These
commenters also generally found the EPA's 2016 change in its historical
interpretation to be reasonable and supported retaining that
interpretation. Other commenters look to the word ``maintenance'' in
section 608 as providing authority for the leak repair provisions. One
commenter states that ``maintenance'' includes normal operation, noting
the definition of maintenance includes ``keep[ing] in an existing
state'' or ``preserv[ing]'' the machinery.\18\ Another comment states
that because proper maintenance includes fixing leaks, failure to
adequately repair leaks violates the venting prohibition.
---------------------------------------------------------------------------

    \18\ Maintain, MERRIAM-WEBSTER ONLINE DICTIONARY, https://www.merriam-webster.com/dictionary/maintain (last visited Nov. 15,
2018).
---------------------------------------------------------------------------

    The EPA disagrees with commenters that state that the ``topping
off'' of a leaking appliance is necessarily prohibited under section
608(c). The addition of refrigerant to an appliance during service,
maintenance, or repair is typically distinct and separate in time from
the release of that refrigerant into the environment from a leak during
the normal operation of the appliance. As discussed elsewhere in this
document, while there may be a release of refrigerant from a leaking
appliance, all appliances leak and such leaks typically occur during
normal operations. While there may be cases where there would be an
ongoing release of refrigerant such that the refrigerant added to the
system is contemporaneously released and the technician knows about
such a release during the servicing event (e.g., when refrigerant is
added to equipment that is audibly or visibly leaking during the
servicing event), the EPA does not have any information to suggest that
this is the norm. Accordingly, the EPA does not have any information to
suggest that these situations are common enough to sustain an extension
of the leak repair requirements to equipment using solely substitute
refrigerants under the text of section 608(c).
    The EPA also disagrees with the commenters suggesting that
inclusion of the term ``maintaining'' in section 608(c) provides the
agency authority to apply the leak repair provisions to appliances
containing only substitute refrigerants. Contrary to the position that
the EPA took in the 2016 Rule (81 FR 82291), the EPA concludes in this
action that the term ``maintaining'' in section 608(c) is not meant to
encompass the normal operation of an appliance. Rather, as discussed in
Section II above, the EPA believes it is reasonable to interpret this
term in light of the other terms in section 608(c) (servicing,
repairing, or disposing), all of which refer to activities that are
distinct from the normal, day-to-day operation of the equipment. The
EPA also disagrees with the commenters suggesting that failure to
repair leaks is a failure to maintain equipment that necessarily
results in releases that violate the venting prohibition. The text of
section 608(c)(1) prohibits knowing releases of ODS by ``any person, in
the course of maintaining, servicing, repairing, or disposing'' of
appliances, and section 608(c)(2) extends that prohibition to knowing
releases of substitute refrigerants ``by any person maintaining,
servicing, repairing, or disposing of'' an appliance. Thus, section
608(c) requires an actor (e.g., a technician) to conduct one of a
particular set of actions on an object (an appliance) in order for the
venting prohibition to apply. The four terms ``maintaining, servicing,
repairing, or disposing'' included in section 608(c) are all forms of
transitive verbs that express an action by an actor (``any person'') on
an object (an appliance containing or using refrigerant). Interpreting
the term ``maintaining'' as encompassing the lack of maintenance or
failure to repair leaks unreasonably transforms the prohibition against
knowing releases during certain defined activities into a requirement
to undertake those activities. In the EPA's view, it is not reasonable
to interpret the term ``maintaining'' to encompass normal, day-to-day
operations of an appliance or to encompass failure to maintain an
appliance. Rather, the EPA concludes that the term ``maintaining'' as
used in section 608(c) should be interpreted to refer to work done on
an appliance in furtherance of its continued functioning or to preserve
its existing state of repair. (See, e.g., The American Heritage College
Dictionary, 4th ed. (Houghton Mifflin, 2002), at 834 (listing
definitions of ``maintain'' which include ``to keep in an existing
state; preserve or retain'' and to ``keep in a condition of good repair
or efficiency''); Merriam Webster's Collegiate Dictionary, 11th ed.
(Merriam Webster Inc., 2003), at 749 (definitions of ``maintain''
include ``to keep in an existing state (as of repair, efficiency, or
validity): preserve from failure or decline <~machinery>'')).
    The EPA disagrees with the comments that its historic
interpretation, to which it returns today, is inconsistent with the
purpose of section 608(c). As explained in Section II above, a general
analysis of whether a provision leads to reductions in ODS emissions
would typically be undertaken under section 608(a). In contrast to
section 608(a), which requires regulations to reduce emissions of ODS
to the lowest achievable level, the agency interprets section 608(c) as
focusing on limiting particular types of emissions of ODS and
substitute refrigerants--those from knowing releases, venting, and
disposal that occur in the course of maintaining, servicing, repairing,
or disposing of appliances. The agency views its return to its historic
interpretation in this action as consistent with the purposes of
section 608(c) because it better focuses the regulations on knowing
releases that occur during the activities listed in 608(c). In this
interpretation it is not the quantity of refrigerant released, but
rather the circumstances of the release that determine whether the
venting prohibition applies. The EPA concludes that its legal authority
under section 608(c)(2) does not extend to emissions of substitute
refrigerants that do not occur during one of those four activities.
Thus, the agency agrees with the comments stating that the release must
occur during the service, maintenance, repair, or disposal of an
appliance to be prohibited under the venting prohibition.
    A couple of commenters request that the EPA clarify how rescinding
the 2016 Rule's interpretation--that ``topping off'' a leaking
appliance could in some circumstances constitute a knowing release and
violate the venting prohibition--affects appliances containing ODS
refrigerant. Noting that the proposed rule states that the Agency was
not modifying any ODS provisions, the commenters state that the EPA
should rescind this interpretation as it applies to ODS appliances as
well. The EPA responds that the agency is rescinding this
interpretation for all appliances, regardless of the type of
refrigerant used. The original interpretation that topping off an
appliance was not a knowing release was in the context of appliances
containing ODS refrigerant. (58 FR 28672). Thus, reverting back to that
original interpretation means it applies to appliances using ODS
refrigerant, as well as to those using non-ODS refrigerants. We further
note that this return to the original interpretation does not change
the required leak repair practices in Sec.  82.157 for ODS equipment,
as those requirements reduce the emissions of ODS and maximize the
recapture and recycling of ODS as provided in section 608(a). In

addition, the agency is not changing the requirement under Sec.
82.154(a)(2)(i) that ODS releases only qualify for the de minimis
exemption if certain regulatory practices, including those in Sec.
82.157, have been observed.

C. Comments on Whether Section 608(a) Provides Any Statutory Authority
To Regulate Substitute Refrigerants

    The EPA requested comment on whether, as a matter of statutory
interpretation, the agency can rely on section 608(a) for the issuance
of any of the subpart F requirements (leak repair or otherwise) for
substitute refrigerants, including those provisions for which there is
demonstrably a connection between the regulatory requirement and the
purposes of section 608(a) to reduce use and emission of class I and II
substances to the lowest achievable level and maximize the recapture
and recycling of such substances. As the EPA discussed in the proposal,
Congress specifically required the EPA in section 608(a) to issue
regulations for class I and class II substances that would meet certain
statutory purposes set forth in that section. But Congress did not list
substitutes for coverage by those requirements. In contrast, section
608(c) does expressly apply to substitute refrigerants. This difference
between section 608(a) and 608(c) could be interpreted as a
manifestation of Congressional intent to distinguish between the
categories of substances covered in these respective provisions and to
only convey authority to address substitute refrigerants under 608(c),
not 608(a), which is an issue on which the EPA solicited comment.
    Three commenters state that 608(a) is not ambiguous with respect to
the extent to which Congress authorized the EPA to issue refrigerant
management regulations for substitutes. The commenters state that
Congress did not provide any explicit grant of authority in section
608(a) for the EPA to establish a regulatory program for substitutes.
The fact that Congress so clearly provided such authority for ODS
demonstrates that no such authority exists for substitutes. One of
those commenters concludes that the EPA lacks the discretion it claims
to regulate non-exempt substitutes in any manner.
    Other commenters state that the scope of 608(a) is ambiguous and
that to the extent that the EPA determines that the statutory language
is ambiguous, then the EPA is free to make a policy decision to resolve
the ambiguity. These commenters state that there are many policy
rationales that support regulating non-ODS substitutes to an equal
extent as the regulation of ODS, including cost savings to owners and
operators by encouraging proper leak management, reducing harm to the
atmosphere, and reduced public safety hazards.
    The EPA responds that, as discussed in Section II.B. above, while
section 608(a)(3) states that regulations under 608(a) shall include
requirements that serve particular objectives and discretionary
language about what requirements those regulations may include, it does
not contain any more specific mandates about how the required
objectives should be achieved. Thus, the EPA agrees with the comments
that section 608(a) is ambiguous with respect to the EPA's authority to
regulate substitute refrigerants to achieve those purposes. Given this
ambiguity, the EPA interprets section 608(a) to provide authority to
issue regulations that reduce the use and emission of ODS to the lowest
achievable level or that maximize the recapture and recycling of such
substances, even if the regulations do not directly regulate ODS. Thus,
as in the 2016 Rule, to the extent that the extension of certain
subpart F requirements to non-exempt substitutes is necessary to
achieve the purposes set forth in section 608(a)(3) (i.e., reducing the
use and emission of ODS to the lowest achievable level or maximizing
the recapture and recycling of such substances), the EPA concludes that
the extension is within the ambit of its authority under section
608(a). However, the EPA disagrees with the comments suggesting that
608(a) is so ambiguous as to allow the agency to employ various policy
rationales such as cost savings to the owners and operators,
encouraging proper leak management, reducing harm to the atmosphere,
and reducing public safety hazards when considering whether the
extension of the subpart F requirements to substitute refrigerants is
supported by 608(a). The EPA interprets section 608(a) to authorize the
extension of those requirements only if they meet the explicit
purpose(s) of that section, including reducing the use and emission of
ODS to the lowest achievable level and/or maximizing the recapture and
recycling of such substances. For the reasons discussed in Section II
of this document, the EPA concludes that section 608(a) does not
support the 2016 extension of the leak repair requirements in Sec.
82.157 to non-exempt substitute refrigerants but does support the
extension of the non-leak repair requirements to such refrigerants.
    Some commenters state that 608(a) does not provide authority to
require repairing leaks of non-ODS substitutes because repairing an
appliance containing a substitute will not reduce the use or emission
of ODS nor maximize the recapture and recycling of ODS.
    The EPA responds that, as described in greater detail in Section II
above, the agency interprets CAA section 608(a) to support the 2016
Rule's extension of the existing subpart F requirements to appliances
using only non-exempt substitute refrigerants only if that extension is
necessary to serve the purposes of 608(a). The EPA agrees with these
commenters that applying the leak repair provisions to appliances
containing only substitute refrigerants is not necessary to reduce ODS
emissions or to promote the recapture and recycling of ODS. This is
especially true since the EPA is retaining the non-leak repair
provisions in subpart F for non-exempt substitutes.
    Three commenters state that the text of 608(a) demonstrates that
Congress intended the section to provide an incentive to transition to
non-ODS substitutes. These commenters state that rescinding the leak
repair provisions for non-exempt substitutes will restore that
incentive, which will minimize use and emission of ODS. Likewise, one
commenter states that applying the refrigerant management requirements
to substitutes will disincentivize the development of new substitutes.
    While the EPA is rescinding the leak repair provisions for non-
exempt substitutes based on its determination that the extension of
these provisions to such substitutes exceeded its statutory authority
because it was based on an unreasonable interpretation of that
authority, the EPA disagrees that section 608 drives the development of
or transition to substitutes. Section 608 is one of several
complementary measures in Title VI of the CAA that support the phaseout
of class I and class II ODS. For example, in section 610 Congress
banned certain products containing ODS and granted the EPA authority
under to ban others. In section 611, Congress required the EPA to
promulgate labeling requirements for certain products containing or
manufactured with ODS. These aspects of Title VI more directly
establish incentives and support the transition to ODS alternatives
than the provisions in section 608, which establish a national
recycling and emission reduction program. Further, the production and
import of class I ODS has been phased out and the production and import
of class II ODS is well underway. Allowances for production and import
of the most common HCFC refrigerant, HCFC-22, are set to decline to
zero in 2020 (Sec. Sec.  82.16, 82.15(e)). In addition,

use restrictions issued pursuant to section 605(a) prohibit use of
newly produced HCFC-22 in equipment manufactured on or after January 1,
2010 (Sec.  82.15(g)(2)). The section 605(a) use restrictions further
prohibit use of newly produced HCFC-123 in equipment manufactured on or
after January 1, 2020 (Sec.  82.15(g)(4)). While used HCFCs are not
subject to these restrictions, the HCFC production and import phaseout
and the restrictions on use of newly produced HCFCs provide clear
market signals regarding future availability of HCFC refrigerants.
    Thus, the provisions of Title VI, taken together, provide a variety
of incentives for the transition from ODS to substitutes. In section
608(c)(2), however, Congress indicated a concern about the potential
environmental impacts of substitute refrigerants by extending the
venting prohibition to substitute refrigerants, unless the EPA
determines that for particular substances such releases do not pose a
threat to the environment.
    To the extent that the extension of subpart F regulatory
requirements to non-exempt substitute refrigerants is supported by
section 608(c), that extension provides clarity and certainty to
owners, operators, and people servicing, maintaining, repairing, or
disposing of air conditioning and refrigeration equipment of how they
can avoid violating the venting prohibition. Such clarity and certainty
with regards to the venting prohibition are consistent with the EPA's
overall efforts under Title VI to facilitate a smooth transition from
ODS to substitute refrigerants. Thus, while facilitating a smooth
transition to substitutes is not a basis for this action, the EPA
disagrees with the comments suggesting that applying subpart F
provisions to non-exempt substitute refrigerants reduces incentives for
the development of or transition to substitutes.
    The EPA solicited comment regarding scenarios where failure to
apply consistent standards for the non-leak repair provisions in
Subpart F could lead to emissions of ODS. These scenarios include
contamination caused by the improper handling of non-exempt substitute
refrigerant, equipment failure due to mixed or contaminated
refrigerant, venting of contaminated refrigerant due to cost of
handling and reclaiming refrigerant in appliances, and venting due to
an individual misidentifying an ODS refrigerant as a substitute
refrigerant when performing maintenance on an appliance. (83 FR 49340).
    One commenter states that the EPA provided no technical basis to
warrant the extension of the non-leak repair subpart F requirements to
substitutes. Specifically, the commenter states that the agency did not
provide any data concerning frequency of refrigerant contamination,
equipment failures due to contamination, and misidentification. The
commenter states that its members, including one that has 75 separate
facilities, could not identify any examples of substitute contamination
or mismanagement. Multiple other commenters state that a single,
uniform, and consistent management system for ODS and substitute
refrigerants makes refrigerant management easier for technicians
maintaining, servicing, or disposing of refrigeration equipment, and
increases the chances that technicians will not release class I or
class II refrigerant. Some of these comments were limited to the non-
leak repair provisions of Subpart F and some were inclusive of the leak
repair provisions. Several refrigerant technicians and reclaimers in
their comments relay instances where a layperson has mixed refrigerant
or attempted an improper retrofit or other maintenance and caused the
release of refrigerant. Other commenters state that refrigerant mixing
would increase if the sales restriction for non-exempt substitutes were
rescinded.
    The EPA's understanding of the industry indicates that technician
errors can result in refrigerant mixing, and catastrophic equipment
failure as a result. The agency's understanding is consistent with and
supported by information that stakeholders have provided to the agency,
including information submitted during the development of this
rulemaking and included in the record for this rule. Moreover, the EPA
has supporting evidence from enforcement actions pertaining to R-22a
and reported reclamation data that mixing does occur. Many entities
including refrigerant reclaimers, equipment manufacturers, technicians,
and equipment owners have notified the agency that mixed refrigerant is
becoming increasingly prevalent as the number of substitutes for ODS in
use increases. The EPA finds credible the information provided by
commenters who identified examples of refrigerant releases related to
mixing of refrigerants or attempted improper retrofit or other
maintenance.
    Evidence of refrigerant mixing comes from data reported to the EPA
by reclaimers. The amount of mixed refrigerant being received by
reclaimers has been increasing since 2012 by total volume or since 2013
as a percentage of the amount of refrigerant sent for reclamation.
These data support the anecdotal statements and comments made by
individual reclaimers and technicians that they are encountering more
mixed refrigerant. The data are available on the EPA's website and some
of the comments and statements are in the docket to this rule.\19\ The
EPA also expects that the reported data are an underestimate of the
total amount of mixed refrigerant since mixed refrigerant is often
vented or not sent to reclaimers, and thus those amounts are
unavailable to be reported.
---------------------------------------------------------------------------

    \19\ Mixed Refrigerant Received Totals by Year (Pounds),
available at https://www.epa.gov/section608/summary-refrigerant-reclamation-trends.
---------------------------------------------------------------------------

    In addition, as discussed in the 2016 Rule, the use of R-22a (a
non-exempt substitute refrigerant) as a replacement for R-22 (an ODS
refrigerant) indicates to the EPA that people are purchasing their own
refrigerant and adding it to systems with ODS refrigerant. R-22a, which
is propane, in some cases mixed with isobutane and an odorant, has been
marketed as a ``drop-in'' (or more appropriately termed a ``retrofit'')
replacement for existing equipment, typically residential split air-
conditioning systems, which are designed for use with HCFCs or HFCs.
The EPA has listed propane and R-22a as well as all ASHRAE Flammability
Class 3 Refrigerants as unacceptable for retrofit in residential and
light commercial unitary split AC and heat pumps under the Significant
New Alternatives Policy program. The Agency learned through its
enforcement actions against Enviro-Safe and Northcutt, two distributors
of R-22a, and through other investigations, that R-22a has been sold to
both consumers and certified technicians. Often the buyers are not
aware there is a difference between R-22 and R-22a, or even that R-22a
is flammable. As a result, appliances have exploded, resulting in the
release of refrigerant that consists in part of ODS, and people have
been injured. Together, this data from reclaimers and information on R-
22a support the view that applying the sales restriction and technician
certification requirements to non-exempt substitute refrigerants serves
the purposes of section 608(a) because it prevents the mixing and
subsequent release of ODS refrigerants, including in mixtures with
substitute refrigerants.
    Two commenters state that cross-contamination of ODS and non-exempt
substitute refrigerant does not occur because they operate at different
pressures so there are no concerns that ODS will be emitted if there
are no

controls on substitute refrigerants. In contrast, another commenter
states that many class II (and in some cases, class I) substances can
be used interchangeably with HFCs and other substitute refrigerants,
though sometimes requiring equipment modification. Other commenters
state that ODS and ODS substitutes can be used interchangeably in many
applications, and service technicians are likely to encounter both
types of refrigerants. In California, approximately 17% of reporting
facilities have both ODS and HFC systems.
    The EPA disagrees with the comment saying that cross-contamination
of ODS and non-exempt substitute refrigerant cannot occur because they
operate at different pressures. R-22 has been the dominant ODS
refrigerant and is being replaced with several non-exempt substitute
refrigerants that operate at similar pressures (e.g., R-404A, R-407A,
and R-407C). In those situations, cross-contamination of ODS and
substitute refrigerant, refrigerant mixing, and related releases of ODS
can occur. The EPA agrees with the comments that ODS and substitute
refrigerants have inappropriately been used interchangeably. The EPA
frequently hears from industry stakeholders, similar to comments
received on the proposal, that technicians are ``topping off'' R-22
systems with non-exempt substitute refrigerant, particularly during the
final stages of the R-22 phaseout which has seen price spikes. Improper
retrofits or refrigerant mixing can occur even when the operating
pressure is different, especially when appliances are serviced by
untrained personnel. This mixing of refrigerant with different
operating pressure makes catastrophic equipment failure and release of
the refrigerant charge even more likely.
    A few commenters state that eliminating the reclamation requirement
for non-exempt substitute refrigerants would set in motion market
forces that would ultimately result in an increase in ODS emissions.
Specifically, the commenter states that technicians would resell
recovered substitute refrigerants to other customers rather than
sending them for reclamation. This would reduce the profitability and
ability of reclaimers to reclaim the ODS refrigerants that they do
receive. The comment explains that reclaimers might stop accepting ODS
refrigerants and technicians would then either resell contaminated
refrigerant, vent the ODS refrigerants to the atmosphere, or pay for
proper disposal, likely in that order.
    The EPA agrees with the comments that rescinding the reclamation
requirements for non-exempt substitute refrigerants would likely result
in an increase in ODS emissions. As discussed further in Section II.D.
of this document, the reclamation requirements for non-exempt
substitute refrigerant prohibit the resale of mixed used refrigerant
and support a market-based process from the technician or recovery
company to the refrigerant distributor and ultimately the reclaimer to
return used ODS and non-exempt substitute refrigerant to the same
purity level as newly produced refrigerant. The requirement that
recovered ODS and non-exempt substitute refrigerant be reclaimed to
meet industry purity standards before being resold, with limited
exceptions, implements the direction in section 608(a)(3) to reduce the
use and emission of ODS to the lowest achievable level, and to maximize
the recapture and recycling of such substances, as explained further in
Section II.D. of this document. The EPA concludes that section 608
provides the EPA authority for the 2016 Rule's extension of the
reclamation requirements to substitute refrigerants and is therefore
not finalizing a rescission of the reclamation standards.

D. Comments Regarding How Holistic Interpretations of Section 608 and
Other Sections of Title VI May Relate to EPA's Authority To Regulate
Substitute Refrigerants

    One commenter states that the EPA must read section 608 as a whole,
consistent with giving meaning to the full statutory provision. This
commenter further asserts that doing so shows that Congress intended to
only stagger requirements for ODS and non-exempt substitutes, with ODS
requirements applying starting in 1992 and those for substitutes
starting in 1995, not to create a more limited regulatory program for
substitutes. A few commenters state that section 608(a) is broader than
608(c) in that it provides the EPA the authority to regulate ``use'' of
an ODS while 608(c) is limited to service, maintenance, repair, or
disposal of an appliance. These commenters state that this difference
in wording indicates that Congress intended for different requirements
to apply to ODS and substitutes. Another commenter states that because
section 608(c)(2) extends to the ``knowing release'' or the disposal of
substitutes, it provides broader legal authority than exists within the
Administrator's authority to establish standards regarding the ``use
and disposal of class I substances'' under CAA section 608(a), offering
the example that CAA section 608(c) authority extends to any
``release'' whether by means other than use or disposal.
    The EPA responds that the agency has appropriately considered the
authority granted to the agency under section 608, considering that
section as a whole, in reaching the interpretations supporting this
action. Based on that consideration, the EPA disagrees that reading
608(a) and (c) together indicates that Congress intended simply to
stagger similar requirements for ODS and substitutes. Were this the
case, Congress could have inserted requirements to regulate substitutes
in 608(a) that were effective in 1995, in a similar manner to the way
it made the venting prohibition effective for substitutes effective
November 15, 1995 in 608(c)(2). But it did not. While Congress chose to
stagger the requirements in 608(a) for class I and class II ODS, with
section 608(a)(1) requiring the EPA to issue certain regulations for
class I substances by January 1, 1992, and 608(a)(2) requiring other
regulations for class I and class II substances by November 15, 1994,
it did not include such a staggered date for substitutes. Nor did it
even mention substitutes in these provisions. Similarly, while Congress
staggered the application of the venting prohibition in section 608(c)
to ODS and substitutes, that only indicates that Congress intended for
the venting prohibition to apply equally to both substitutes and ODS
after November 15, 1995. As explained in greater detail in Section II
of this document, the EPA concludes that, reading section 608 as a
whole, its authority to address substitutes under section 608 is more
limited than its authority to address ODS.
    The EPA agrees with the comment that that the verbs used in section
608(a) suggest a broader scope of authority than those in 608(c). As
noted in Section II above, sections 608(a)(1) and (2) broadly authorize
regulations for the ``use and disposal'' of ODS, and section 608(a)(2)
clarifies that this ``includ[es] use and disposal during service,
repair, or disposal'' of appliances. The term ``includ[es]'' in
608(a)(2) indicates that ``use and disposal'' can occur during
activities other than ``service, repair, or disposal.'' These are three
of the four activities mentioned in section 608(c), which prohibits
knowing releases ``in the course of maintaining, servicing, repairing,
or disposing'' of appliances. As explained elsewhere in this document,
the EPA interprets the fourth term, ``maintaining,'' as similar in
scope to ``servicing, repairing, or disposing'' and to refer to work
done on an appliance in furtherance of its

continued functioning or to preserve its existing state of repair.
Thus, the EPA concludes that Congress envisioned that the regulations
under section 608(a) would affect a broader range of activities than
those under section 608(c). In addition, as described in greater detail
in Section II above, the EPA now reads sections 608(a) and (c) together
to determine that its authority is more limited for substitute
refrigerants than for ODS. However, the EPA does not believe that this
means none of the same provisions can be applied to ODS and substitute
refrigerants. Rather, the EPA believes the same provision can apply to
both ODS and substitute refrigerants where the agency can reasonably
conclude that extending a requirement that previously only applied to
ODS refrigerants to substitute refrigerants is an appropriate
application of its authority under either section 608(a) or (c), under
the interpretive framework set forth in Section II above. The EPA
disagrees with the comment that 608(c)(2) is broader than 608(a)
because it extends to ``any release.'' As discussed in Section II, the
releases prohibited under section 608(c)(2) are limited to those that
occur ``in the course of maintaining, servicing, repairing, or
disposing'' of appliances, a narrower range of activities than the
broad range of ``use and disposal'' activities featured in section
608(a). Two commenters state that reading sections 608 and 612 together
indicates that Congress sought to avoid solving one problem (ozone
depletion) only to create another, in this case GHG emissions. They
argue that given the policy choices that are embodied in section 612--
to replace ODS with substitutes that lower the overall risks to human
health and the environment--and the fact that HFCs have not been
exempted from the venting prohibition, the EPA should take an expansive
read of the Agency's authority to regulate substitutes.
    The EPA responds that CAA sections 612 and 608 are distinct
provisions, and the EPA does not believe it is reasonable to interpret