Document ID: EPA-HQ-OAR-2018-0595-0001
Agency: epa
Document Type: Proposed Rule
Title: Emissions Monitoring Provisions in State Implementation Plans Required under the NOX SIP Call
Posted Date: 2018-09-27T04:00Z

[Federal Register Volume 83, Number 188 (Thursday, September 27, 2018)]
[Proposed Rules]
[Pages 48751-48765]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2018-20858]

[[Page 48751]]

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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Parts 51 and 52

[EPA-HQ-OAR-2018-0595; FRL-9984-19-OAR]
RIN 2060-AU08

Emissions Monitoring Provisions in State Implementation Plans 
Required Under the NOX SIP Call

AGENCY: Environmental Protection Agency (EPA).

ACTION: Proposed rule.

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SUMMARY: The Environmental Protection Agency (EPA) is proposing to 
update the regulations that were originally promulgated in 1998 to 
implement the NOX SIP Call. In place of the current 
requirement for states to include provisions in their state 
implementation plans (SIPs) under which certain emissions sources must 
monitor their mass emissions of nitrogen oxides (NOX) 
according to 40 CFR part 75, the proposed amendments would allow states 
to include alternate forms of monitoring requirements in their SIPs. 
The amendments would also rescind the findings of interstate pollution 
transport obligations with respect to the 1997 8-hour ozone national 
ambient air quality standards (NAAQS) under the NOX SIP Call 
that have been stayed by EPA since 2000. Other revisions would remove 
additional obsolete provisions and clarify the remaining regulations 
but would not substantively alter any current regulatory requirements.

DATES: Comments must be received on or before October 29, 2018. To 
request a public hearing, please contact the person listed in the FOR 
FURTHER INFORMATION CONTACT section by October 4, 2018. EPA does not 
plan to conduct a public hearing unless requested.

ADDRESSES: Submit your comments, identified by Docket ID No. EPA-HQ-
OAR-2018-0595, at https://www.regulations.gov. Follow the online 
instructions for submitting comments. Once submitted, comments cannot 
be edited or removed from regulations.gov. EPA may publish any comment 
received to its public docket. Do not submit electronically any 
information you consider to be Confidential Business Information (CBI) 
or other information whose disclosure is restricted by statute. 
Multimedia submissions (audio, video, etc.) must be accompanied by a 
written comment. The written comment is considered the official comment 
and should include discussion of all points you wish to make. EPA will 
generally not consider comments or comment contents located outside of 
the primary submission (i.e., on the web, cloud, or other file sharing 
system). For additional submission methods, the full EPA public comment 
policy, information about CBI or multimedia submissions, and general 
guidance on making effective comments, please visit https://www.epa.gov/dockets. Additional materials related to this proposed 
action, including submitted comments, can be viewed online at 
regulations.gov under Docket ID No. EPA-HQ-OAR-2018-0595 or in person 
at the EPA Docket Center Reading Room in Washington, DC. Information on 
the location and hours of the EPA Docket Center Reading Room is 
available at https://www.epa.gov/dockets.

FOR FURTHER INFORMATION CONTACT: David Lifland, Clean Air Markets 
Division, Office of Atmospheric Programs, U.S. Environmental Protection 
Agency, MC 6204M, 1200 Pennsylvania Avenue NW, Washington, DC 20460; 
202-343-9151; [email protected].

SUPPLEMENTARY INFORMATION: 

Table of contents

I. Overview of the Proposed Action
    A. Summary of Proposed Amendments and Projected Impacts
    B. Potentially Affected Entities
    C. Statutory Authority and Proposed Determinations Concerning 
Rulemaking Procedures and Judicial Review
    D. Proposed Effective Date
II. Background
    A. The NOX SIP Call
    B. The NOX Budget Trading Program (NBTP) and Related 
Trading Programs
    C. The NOX SIP Call's Contributions to Attainment of 
the NAAQS
III. Proposed Amendments to the NOX SIP Call Regulations
    A. Emissions Monitoring Requirements
    B. Good Neighbor Obligations Under the 1997 8-Hour Ozone NAAQS
    C. Emissions Budget and Emissions Inventory Provisions
    D. Interstate Trading Program Options
    E. Procedural Provisions
    F. Editorial Revisions
IV. Impacts of the Proposed Amendments
V. Request for Comment
VI. Statutory and Executive Order Reviews
    A. Executive Order 12866: Regulatory Planning and Review, and 
Executive Order 13563: Improving Regulation and Regulatory Review
    B. Executive Order 13771: Reducing Regulations and Controlling 
Regulatory Costs
    C. Paperwork Reduction Act
    D. Regulatory Flexibility Act
    E. Unfunded Mandates Reform Act
    F. Executive Order 13132: Federalism
    G. Executive Order 13175: Consultation and Coordination With 
Indian Tribal Governments
    H. Executive Order 13045: Protection of Children From 
Environmental Health and Safety Risks
    I. Executive Order 13211: Actions That Significantly Affect 
Energy Supply, Distribution, or Use
    J. National Technology Transfer Advancement Act
    K. Executive Order 12898: Federal Actions To Address 
Environmental Justice in Minority Populations and Low-Income 
Populations

I. Overview of the Proposed Action

    This section provides an overview of the proposed action, including 
a summary of the proposed amendments and their projected impacts as 
well as information concerning potentially affected entities, statutory 
authority, EPA's proposed determinations concerning applicable 
rulemaking and judicial review provisions, and the proposed effective 
date.
    Section II provides additional background. In section III, EPA 
describes the proposed amendments and the supporting rationales. 
Section IV discusses the projected impacts of the proposed amendments. 
EPA's request for comment is in section V. Section VI addresses reviews 
required under various statutes and Executive Orders.

A. Summary of Proposed Amendments and Projected Impacts

    In 1998, EPA promulgated the NOX SIP Call which, as 
implemented, required 20 states and the District of Columbia to revise 
their SIPs to reduce seasonal NOX emissions contributing to 
interstate ozone pollution. Since implementation of emission controls 
under the NOX SIP Call began in 2003, the regulations have 
required these jurisdictions to include provisions in their SIPs under 
which certain large electricity generating units (EGUs) and large non-
EGU boilers and turbines must monitor their seasonal NOX 
emissions according to the procedures in 40 CFR part 75. The sources 
formerly met these requirements through participation in the 
NOX Budget Trading Program (NBTP), which was discontinued 
after 2008. Almost all the affected large EGUs currently participate in 
the Acid Rain Program or Cross-State Air Pollution Rule (CSAPR) trading 
programs, which have comparable monitoring requirements, but few of the 
affected large non-EGUs participate in these other programs. Over time, 
many of the originally affected large non-EGUs have retired or switched 
to cleaner fuels, and newly affected large non-EGUs generally have 
lower emission rates, so total NOX emissions from the group 
are considerably lower than in the

[[Page 48752]]

past. Several NOX SIP Call states have expressed interest in 
establishing alternate, potentially lower-cost monitoring requirements 
for the remaining large non-EGUs.
    This proposal would revise the existing NOX SIP Call 
regulations to allow states to amend their SIPs to establish emissions 
monitoring requirements for NOX SIP Call purposes other than 
Part 75 monitoring requirements. Ultimately, such alternate monitoring 
requirements could be made available to approximately 310 units--mostly 
large non-EGUs--through states' revisions to their SIPs. States, not 
EPA, would decide whether to revise the monitoring requirements in 
their SIPs, and EPA lacks complete information on the remaining 
monitoring requirements that the sources would face, but EPA expects 
that at least some states would revise their SIPs, resulting in reduced 
monitoring costs for at least some sources. Almost all the large EGUs 
would still be required to perform NOX monitoring according 
to 40 CFR part 75 under the Acid Rain Program or the CSAPR trading 
programs, thereby providing comparable monitoring data for most of the 
collective NOX mass emissions from the set of large EGUs and 
large non-EGU boilers and turbines affected under the NOX 
SIP Call. Further, the monitoring data for recent years show that the 
sets of large EGUs and large non-EGU boilers and turbines in all 
NOX SIP Call states are collectively complying with the 
portions of the statewide emissions budgets assigned to these types of 
sources by substantial margins. Given these circumstances, EPA believes 
that other forms of monitoring for the remaining large EGUs (i.e., 
those not covered under the Acid Rain Program or the CSAPR trading 
programs) and large non-EGU boilers and turbines can now provide 
sufficient assurance that the NOX SIP Call's required 
emissions reductions will continue to be achieved.
    EPA is also proposing to eliminate several obsolete provisions that 
no longer have any substantive effect on the regulatory requirements 
faced by states or sources. For example, the NOX SIP Call 
originally rested independently on parallel findings regarding 
interstate ozone pollution that EPA made with respect to two distinct 
NAAQS: The 1979 1-hour ozone NAAQS and the 1997 8-hour ozone NAAQS. The 
findings made with respect to the 1997 ozone NAAQS were stayed by EPA 
in 2000 and have since been superseded by findings made in more recent 
actions based on updated analyses. In this action, EPA is proposing to 
rescind the indefinitely stayed findings made in the NOX SIP 
Call with respect to the 1997 ozone NAAQS. EPA is also proposing to 
remove obsolete provisions concerning options to revise the 
NOX SIP Call emissions budgets and baseline emissions 
inventories, options to issue credits supplementing the emissions 
budgets, and options to comply with the emissions budgets by using the 
NBTP or state-developed interstate trading programs. An obsolete 
provision concerning SIP submission procedures would also be removed.
    Finally, EPA is proposing to make clarifying amendments to the 
remaining NOX SIP Call regulations. Most notably, existing 
regulatory text mischaracterizing the incremental emissions reductions 
required in states' Phase II SIP submissions as ``Phase II incremental 
budget'' amounts and ``portions of'' the final NOX budgets 
would be replaced by simpler text referencing the Phase I and final 
NOX budgets. The proposed clarifications would not 
substantively alter any existing regulatory requirements.
    No substantive amendments are proposed to any existing requirements 
of the NOX SIP Call except the existing requirement for SIPs 
to include provisions under which large EGUs and large non-EGU boilers 
and turbines must monitor their NOX emissions in accordance 
with 40 CFR part 75. The emissions reductions achieved by the 
NOX SIP Call have been relied on to support numerous final 
actions redesignating areas to attainment of a NAAQS, and consistent 
with that reliance the emissions reductions must be permanent and 
enforceable. To ensure the permanence and enforceability of the 
emissions reductions, other existing NOX SIP Call 
requirements regarding large EGUs and large non-EGU boilers and 
turbines, including requirements for SIPs to contain provisions 
establishing some form of enforceable seasonal NOX mass 
emissions limits for these sources supported by some form of monitoring 
requirements, are not affected by the proposed amendments and would 
remain in place, as would all of the more broadly applicable 
requirements regarding SIPs and the statewide emissions budgets. EPA is 
not reopening, and thus is not accepting comment on, any of the 
NOX SIP Call provisions other than the ones proposed for 
revision. With respect to the NOX SIP Call provisions 
proposed for revision other than the provision concerning Part 75 
monitoring requirements, EPA is not reopening any of the provisions on 
a substantive basis and is accepting comment solely on whether the 
provisions proposed for removal as obsolete in fact are obsolete and on 
whether the proposed clarifications in fact achieve clarification.
    EPA is not proposing to amend any other regulations under which 
some sources affected under the NOX SIP Call may also face 
monitoring requirements. Such other regulations include, but are not 
limited to, regulations for the Acid Rain Program (40 CFR parts 72 
through 78) and the CSAPR trading programs (40 CFR part 97, subparts 
AAAAA through EEEEE). EPA is not reopening, and thus is not accepting 
comment on, any such other regulations.

B. Potentially Affected Entities

    This proposed action would not apply directly to any emissions 
sources but instead would amend existing regulatory requirements 
applicable to the SIPs of Alabama, Connecticut, Delaware, Illinois, 
Indiana, Kentucky, Maryland, Massachusetts, Michigan, Missouri, New 
Jersey, New York, North Carolina, Ohio, Pennsylvania, Rhode Island, 
South Carolina, Tennessee, Virginia, West Virginia, and the District of 
Columbia. If an affected jurisdiction chooses to revise its SIP in 
response to these amendments, sources in the jurisdiction could be 
indirectly affected if they are subject to emissions monitoring 
requirements for purposes of the NOX SIP Call and are not 
independently subject to comparable requirements under another program 
such as the Acid Rain Program or a CSAPR trading program. Generally, 
the types of sources that could be affected are fossil fuel-fired 
boilers and stationary combustion turbines with heat input capacities 
over 250 million British thermal units per hour (mmBtu/hr) or serving 
electricity generators with capacities over 25 megawatts (MW). Sources 
meeting these criteria operate in a variety of industries, including 
but not limited to the following:

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                                         Examples of industries with
           NAICS * code                 potentially affected sources
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221112............................  Fossil fuel-fired electric power
                                     generation.
3112..............................  Grain and oilseed milling.
3221..............................  Pulp, paper, and paperboard mills.
3241..............................  Petroleum and coal products
                                     manufacturing.
3251..............................  Basic chemical manufacturing.
3311..............................  Iron and steel mills and ferroalloy
                                     manufacturing.
6113..............................  Colleges, universities, and
                                     professional schools.
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* North American Industry Classification System.

[[Page 48753]]

C. Statutory Authority and Proposed Determinations Concerning 
Rulemaking Procedures and Judicial Review

    Statutory authority for the amendments proposed in this action is 
provided by Clean Air Act (CAA) sections 110 and 301, 42 U.S.C. 7410 
and 7601, which also provided statutory authority for issuance of the 
existing NOX SIP Call regulations that EPA is proposing to 
amend.
    CAA section 307(d), 42 U.S.C. 7607(d), contains rulemaking and 
judicial review provisions that apply to certain EPA actions under the 
CAA including, under section 307(d)(1)(V), ``such other actions as the 
Administrator may determine.'' In accordance with section 307(d)(1)(V), 
the Administrator proposes to determine that the provisions of section 
307(d) apply to any final action taken on this proposal. EPA has 
complied with the procedural requirements of section 307(d) during the 
course of this rulemaking.
    CAA section 307(b)(1), 42 U.S.C. 7607(b)(1), indicates which United 
States Courts of Appeals have venue for petitions of review of final 
actions by EPA. This section provides, in part, that petitions for 
review must be filed in the United States Court of Appeals for the 
District of Columbia Circuit (D.C. Circuit) if (i) the Agency action 
consists of ``nationally applicable regulations promulgated, or final 
action taken, by the Administrator,'' or (ii) the action is locally or 
regionally applicable, but ``such action is based on a determination of 
nationwide scope or effect and if in taking such action the 
Administrator finds and publishes that such action is based on such a 
determination.'' EPA proposes to find that any final action taken on 
this proposal is ``nationally applicable'' or, in the alternative, is 
based on a determination of ``nationwide scope and effect'' within the 
meaning of section 307(b)(1). The proposed rule would amend existing 
regulations that apply to 20 states and the District of Columbia, and 
thus the proposed rule would apply to the same jurisdictions. The 
existing regulations that would be amended were promulgated to address 
interstate transport of air pollution across the eastern half of the 
nation and have been relied on as a basis for actions redesignating 
areas in at least 20 states to attainment with one or more NAAQS. 
Previous final actions promulgating and amending the existing 
regulations were nationally applicable and reviewed in the D.C. 
Circuit,\1\ and courts have found other similar actions to be 
nationally applicable.\2\ Finally, the jurisdictions to which the 
proposed rule would apply are located in nine federal judicial 
circuits, and in the report on the 1977 CAA Amendments that revised 
section 307(b)(1), Congress noted that the Administrator's 
determination that an action is of ``nationwide scope or effect'' would 
be appropriate for any action that has a scope or effect beyond a 
single judicial circuit.\3\ For these reasons, the Administrator 
proposes to determine that any final action related to the proposed 
rule is nationally applicable or, in the alternative, is based on a 
determination of nationwide scope and effect for purposes of section 
307(b)(1).
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    \1\ The U.S. Court of Appeals for the Fourth Circuit transferred 
a challenge to one of these actions to the D.C. Circuit after 
determining that the action was nationally applicable. See W. Va. 
Chamber of Commerce v. Browner, No. 98-1013, 1998 U.S. App. LEXIS 
30621, at *24 (4th Cir. Dec. 1, 1998) (finding the NOX 
SIP Call to be nationally applicable based on ``the nationwide scope 
and interdependent nature of the problem, the large number of 
states, spanning most of the country, being regulated, the common 
core of knowledge and analysis involved in formulating the rule, and 
the common legal interpretation advanced of section 110 of the Clean 
Air Act'').
    \2\ See, e.g., Texas v. EPA, No. 10-60961, 2011 U.S. App. LEXIS 
5654 (5th Cir. Feb. 24, 2011) (finding a SIP call to 13 states to be 
nationally applicable and thus transferring the case to the D.C. 
Circuit in accordance with CAA section 307(b)(1)). Cf. Judgment, 
Cedar Falls Utils. v. EPA, No. 16-4504 (8th Cir. Feb. 22, 2017) 
(transferring a petition to review the CSAPR Update to the D.C. 
Circuit).
    \3\ H.R. Rep. No. 95-294, at 323-24 (1977), reprinted in 1977 
U.S.C.C.A.N. 1402-03.
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D. Proposed Effective Date

    If the amendments proposed in this action are finalized, EPA 
intends to make them effective immediately upon publication of a final 
action in the Federal Register. EPA expects that any final action would 
not be subject to requirements specifying a minimum period between 
publication and effectiveness under either Congressional Review Act 
(CRA) section 801(a)(3), 5 U.S.C. 801(a)(3), or Administrative 
Procedure Act (APA) section 553(d), 5 U.S.C. 553(d).
    CRA section 801(a)(3) generally prohibits a ``major rule'' from 
taking effect earlier than 60 days after the rule is published in the 
Federal Register. Generally, under CRA section 804(2), 5 U.S.C. 804(2), 
a major rule is a rule that the Office of Management and Budget (OMB) 
finds has resulted in or is likely to result in (1) an annual effect on 
the economy of $100 million or more, (2) major cost or price increases, 
or (3) other significant adverse economic effects. EPA expects that any 
final rule issued based on this proposal would not be a major rule for 
CRA purposes.
    As discussed in section I.C., EPA is proposing to issue the 
amendments under CAA section 307(d). This provision does not include 
requirements governing the effective date of a rule promulgated under 
it and, accordingly, EPA has discretion in establishing the effective 
date. While APA section 553(d) generally provides that rules may not 
take effect earlier than 30 days after they are published in the 
Federal Register, CAA section 307(d)(1) clarifies that ``[t]he 
provisions of [APA] section 553 . . . shall not, except as expressly 
provided in this section, apply to actions to which this subsection 
applies.'' Thus, APA section 553(d) would not apply to the amendments. 
Nevertheless, in proposing to make any final action taken on this 
proposal effective immediately upon publication, EPA has considered the 
purposes underlying APA section 553(d). The primary purpose of the 
prescribed 30-day waiting period is to give affected parties a 
reasonable time to adjust their behavior and prepare before a final 
rule takes effect. The amendments proposed in this action would not 
impose any new regulatory requirements and therefore would not 
necessitate time for affected sources to adjust their behavior or 
otherwise prepare for implementation. Further, APA section 553(d) 
expressly allows an effective date earlier than 30 days after 
publication for a rule that ``grants or recognizes an exemption or 
relieves a restriction.'' This proposal would relieve an existing 
restriction and allow EPA to approve SIPs with more flexible monitoring 
requirements, which in turn could lead to reduced monitoring costs for 
certain sources. Consequently, making the amendments effective 
immediately upon publication of a final action would be consistent with 
the purposes of APA section 553(d).

II. Background

    This section provides background on the NOX SIP Call, 
the NOX Budget Trading Program (NBTP) and its successor 
trading programs, and EPA's and states' reliance on the resulting 
emissions reductions to support redesignations of areas to attainment 
of the NAAQS.

A. The NOX SIP Call

    Under the CAA, EPA establishes and periodically revises NAAQS for 
certain pollutants, including ground-level ozone, while states have 
primary responsibility for attaining the NAAQS through the adoption of 
control measures in their SIPs. Under CAA section 110(a)(2)(D)(i)(I), 
42 U.S.C. 7410(a)(2)(D)(i)(I), often called the ``good neighbor 
provision,'' each state is required to include provisions in its SIP 
prohibiting emissions that ``will . . .

[[Page 48754]]

contribute significantly to nonattainment in, or interfere with 
maintenance by, any other State with respect to any [NAAQS].'' In 1998, 
EPA issued the NOX SIP Call (the Rule) identifying good 
neighbor obligations with respect to the 1979 1-hour ozone NAAQS and 
the 1997 8-hour ozone NAAQS and calling for SIP revisions to address 
those obligations.\4\ As originally promulgated and codified at 40 CFR 
51.121 and 51.122, the Rule required 22 states \5\ and the District of 
Columbia \6\ to revise their SIPs to reduce their sources' emissions of 
NOX, an ozone precursor, during the May-September ``ozone 
season.'' The original deadline for implementation of controls to 
accomplish the required emissions reductions was May 1, 2003.
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    \4\ Finding of Significant Contribution and Rulemaking for 
Certain States in the Ozone Transport Assessment Group Region for 
Purposes of Reducing Regional Transport of Ozone (NOX SIP 
Call), 63 FR 57356 (Oct. 27, 1998).
    \5\ In addition to the jurisdictions currently subject to 
requirements under the NOX SIP Call as amended, the Rule 
as originally issued also applied to Georgia and Wisconsin.
    \6\ For simplicity, this document often refers to all the 
jurisdictions with obligations under the CAA and the NOX 
SIP Call, including the District of Columbia, as ``states.''
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    In the NOX SIP Call rulemaking, EPA developed and 
applied a 4-step framework that has since formed the basis for all 
subsequent EPA rulemakings to address the good neighbor provision. The 
four steps are to: (1) Identify areas that are projected to have 
problems attaining or maintaining the NAAQS; (2) identify upwind states 
whose emissions warrant further analysis because of linkages to 
problematic air quality in downwind areas in other states; (3) 
determine the amounts of emissions that linked upwind states must 
eliminate (if any) to meet their good neighbor obligations, considering 
both air quality and cost factors; and (4) implement the required 
emissions reductions through enforceable control measures. For purposes 
of this proposed action, only the third and fourth of these four 
steps--determination of the amounts of required emissions reductions 
and implementation of the required reductions--merit discussion.\7\
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    \7\ The following paragraphs summarize relevant background 
information from the more detailed description of the rulemaking 
process in the preamble for the final Rule at 63 FR 57405-76.
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    Based on analysis of both air quality and cost factors, as noted 
above, EPA determined in the NOX SIP Call rulemaking that 
the amount of each state's required emissions reduction under the Rule 
should be the portion of the state's projected 2007 emissions inventory 
\8\ that could be eliminated through the application of highly cost-
effective controls. The 2007 emissions inventories spanned the full 
range of economic sectors, including EGU and non-EGU stationary point 
sources, smaller stationary (area) sources, and highway and nonroad 
mobile sources. After evaluating potential emission control 
opportunities across both stationary and mobile sectors, EPA identified 
sufficiently cost-effective control opportunities and quantified the 
resulting potential emissions reductions for four categories of fossil 
fuel-fired combustion devices: EGU boilers and turbines serving 
electricity generators with capacity ratings greater than 25 MW (large 
EGUs); non-EGU boilers and turbines with heat input ratings greater 
than 250 mmBtu/hr (large non-EGU boilers and turbines); stationary 
internal combustion engines; and cement kilns. In aggregate across all 
covered states, large EGUs accounted for approximately 83 percent of 
the total quantified potential emissions reductions, and the other 
three categories collectively accounted for approximately 17 
percent.\9\
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    \8\ The NOX SIP Call rulemaking made extensive use of 
2007 emissions inventory information and air quality modeling 
results developed through the 1995-1997 Ozone Transport Assessment 
Group (OTAG) process, a collaborative effort of states, industry, 
environmental organizations, and EPA to analyze the causes of 
transported ozone pollution throughout the eastern United States and 
assess possible mitigation strategies.
    \9\ Out of the Rule's total quantified potential emissions 
reductions of 1,156,638 tons, EPA quantified potential emissions 
reductions from EGUs and non-EGUs of 957,975 tons and 198,663 tons, 
respectively. See 63 FR at 57434, 57436, and 57440 (differences 
between ``Base'' and ``Budget'' totals in Tables III-5, III-7, and 
III-11).
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    To implement the Rule's emissions reduction requirements, EPA 
promulgated a ``budget'' for the statewide seasonal NOX 
emissions from each covered state. Each state's emissions budget was 
calculated as the state's projected 2007 emissions inventory minus the 
state's required emissions reduction. Notwithstanding EPA's own 
conclusions concerning the types of sources for which highly cost-
effective controls were available, the Rule did not mandate that states 
follow any particular approach for achieving their required emissions 
reductions. Instead, states retained wide discretion regarding which 
sources in their states to control and what control measures to employ. 
Each state was simply required to demonstrate that whatever control 
measures it chose to include in its SIP revision would be sufficient to 
ensure that projected 2007 statewide seasonal NOX emissions 
from its sources would not exceed its emissions budget.
    Besides the general flexibility given to states regarding the 
choices of sources and control measures, the NOX SIP Call 
included additional provisions designed to increase compliance 
flexibility. First, the Rule established a compliance supplement pool 
of additional credits beyond the emissions budgets. States could issue 
credits from the pool according to criteria established in the Rule, 
and sources could use the credits to demonstrate compliance during the 
first two years in which emission controls were required. Second, the 
Rule allowed states to adopt interstate emission allowance trading 
programs as control measures to accomplish some or all of the required 
emissions reductions. EPA also provided a model rule for an EPA-
administered interstate trading program--the NBTP--that would meet all 
the Rule's SIP approval criteria for a trading program for large EGUs 
and large non-EGU boilers and turbines.
    While generally oriented toward providing states and sources with 
compliance flexibility, the NOX SIP Call also included two 
conditional provisions that would become mandatory SIP requirements for 
large EGUs and large non-EGU boilers and turbines if states chose to 
include any emission control measures for these types of sources in 
their SIP revisions. First, under Sec.  51.121(f)(2), any control 
measures imposed on these types of sources would be required to include 
enforceable limits on the sources' seasonal NOX mass 
emissions. These limits could take several forms, including either 
limits on individual sources or collective limits on the group of all 
such sources in a state. Second, under Sec.  51.121(i)(4), these 
sources would be required to monitor and report their seasonal 
NOX mass emissions according to the provisions of 40 CFR 
part 75.\10\ One way a state could meet these two SIP requirements was 
to adopt the NBTP, because the NBTP included provisions addressing both 
requirements and was expressly designed as a potential control measure 
for these types of sources. However, it is important to recognize that 
the mandatory SIP requirements for large EGUs and large non-EGU boilers 
and turbines, once triggered by a state's choice to adopt any control 
measures for these types of sources into its SIP, exist independently 
of the NBTP. The mandatory SIP requirements therefore

[[Page 48755]]

were not eliminated by the later discontinuation of the NBTP.
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    \10\ For brevity, this notice generally refers to the 
monitoring, recordkeeping, and reporting requirements in 40 CFR part 
75 as ``Part 75 monitoring requirements.''
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    Following initial promulgation, EPA amended the NOX SIP 
Call several times. One amendment in 2000 was prompted by a D.C. 
Circuit opinion concerning the 1997 8-hour ozone NAAQS.\11\ The court's 
decision created uncertainty concerning EPA's authority to implement 
this NAAQS, and in response EPA indefinitely stayed the findings of 
good neighbor obligations under this NAAQS as a basis for the Rule 
pending resolution of the uncertainty.\12\ Because all the Rule's 
requirements rested independently on the findings of good neighbor 
obligations under the 1979 1-hour ozone NAAQS, the stay--which remains 
in place--had no consequence for the Rule's implementation.
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    \11\ Am. Trucking Assns. v. EPA, 175 F.3d 1027 (D.C. Cir. 1999), 
affirmed in part and reversed in part sub nom. Whitman v. Am. 
Trucking Assns., 531 U.S. 457 (2001).
    \12\ 65 FR 56245 (Sept. 18, 2000) (codified at 40 CFR 
51.121(q)).
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    Between 1998 and 2004, EPA made several other amendments to reflect 
updated information and to respond to other D.C. Circuit opinions and 
orders concerning the NOX SIP Call itself.\13\ Collectively, 
these amendments (1) eliminated emissions reduction requirements for 
Wisconsin and portions of Alabama, Georgia, Michigan, and Missouri; (2) 
modified definitions used to classify certain units as EGUs or non-
EGUs; (3) revised the projected 2007 emissions inventories and the 
emissions budgets; (4) accommodated court-imposed deferrals of the 
Rule's original deadlines for SIP submissions and implementation of 
emission controls; and (5) divided the Rule's overall emissions 
reduction requirements into two phases, with implementation of the 
first and second phases of reductions required by May 31, 2004 and May 
1, 2007, respectively.\14\ In an additional pair of amendments in 2005 
and 2008, EPA first stayed and then eliminated emissions reduction 
requirements for the remaining portion of Georgia.\15\
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    \13\ Most judicial challenges to the Rule and its amendments 
were denied, but the court vacated or remanded with respect to 
certain issues in Michigan v. EPA, 213 F.3d 663 (D.C. Cir. 2000) and 
Appalachian Power Co. v. EPA, 251 F.3d 1026 (D.C. Cir. 2001).
    \14\ For a discussion of all amendments to the NOX 
SIP Call through 2004, see 69 FR 21604 (Apr. 21, 2004).
    \15\ For a discussion of the Georgia-related amendments, see 73 
FR 21528 (Apr. 22, 2008).
---------------------------------------------------------------------------

    As amended, the NOX SIP Call applies to Connecticut, 
Delaware, Illinois, Indiana, Kentucky, Maryland, Massachusetts, New 
Jersey, New York, North Carolina, Ohio, Pennsylvania, Rhode Island, 
South Carolina, Tennessee, Virginia, and West Virginia; portions of 
Alabama, Michigan, and Missouri; and the District of Columbia. All 
these jurisdictions except Missouri adopted the NBTP for large EGUs and 
large non-EGU boilers and turbines as part of their Phase I SIP 
submissions. Missouri, which was not required to make a Phase I SIP 
submission, adopted the NBTP for the same types of sources as part of 
its Phase II SIP submission. By adopting control measures applicable to 
large EGUs and large non-EGU boilers and turbines into their SIPs, all 
the affected jurisdictions triggered obligations for their SIPs to 
include enforceable mass emissions limits and Part 75 monitoring 
requirements for these types of sources. As noted above, these 
requirements remain in effect despite the later discontinuation of the 
NBTP.\16\
---------------------------------------------------------------------------

    \16\ Some states expanded NBTP applicability under their SIPs to 
include additional sources, primarily smaller EGUs. Unlike large 
EGUs and large non-EGU boilers and turbines, the additional sources 
are not subject to the NOX SIP Call's ongoing obligation 
under Sec.  51.121(i)(4) for SIPs to include part 75 monitoring 
requirements and therefore would not be affected by the amendments 
proposed in this action.
---------------------------------------------------------------------------

B. The NOX Budget Trading Program (NBTP) and Related Trading Programs

    As described in section II.A., EPA developed the NBTP as a 
potential control measure for large EGUs and large non-EGU boilers and 
turbines that states could adopt into their SIPs to achieve some or all 
of the emissions reductions required under the NOX SIP Call, 
and all covered states chose to adopt the program into their SIPs as a 
control measure for these types of sources. To provide further context 
for the amendments to the NOX SIP Call proposed in this 
action, this section briefly discusses the relationships and relevant 
differences between the NBTP and several other interstate emission 
allowance trading programs that have preceded or followed it.
    The NBTP was implemented starting in 2003, succeeding a similar but 
geographically narrower interstate trading program called the Ozone 
Transport Commission (OTC) NOX Budget Program. The OTC 
trading program, which was developed by several northeastern states 
with EPA assistance, operated from 1999 through 2002. Like the NBTP, it 
applied to both large EGUs and large non-EGU boilers and turbines. 
After issuance of the NOX SIP Call, the northeastern states 
elected to replace the OTC trading program with the NBTP starting in 
2003, approximately one year before the NOX SIP Call's 
amended deadline for implementation of Phase I emission controls. In 
2004, the NBTP expanded to include sources in most of the remaining 
NOX SIP Call states. Missouri sources joined the NBTP in 
2007, and EPA continued to administer the NBTP through the 2008 ozone 
season.
    Since the 2008 ozone season, EPA has replaced the NBTP with a 
series of three similar interstate emission allowance trading programs 
designed to address eastern states' good neighbor obligations with 
respect to ozone NAAQS more recent than the 1979 1-hour ozone NAAQS 
that underlies the NOX SIP Call as amended. The NBTP's three 
successor seasonal NOX trading programs were established 
under the Clean Air Interstate Rule (CAIR),\17\ which was remanded by 
the D.C. Circuit; \18\ the original CSAPR,\19\ which replaced CAIR; and 
most recently the CSAPR Update.\20\ The seasonal NOX trading 
programs established under CAIR and the original CSAPR were both 
designed to address the 1997 8-hour ozone NAAQS,\21\ while the trading 
program established under the CSAPR Update was designed to address the 
2008 8-hour ozone NAAQS. The CAIR seasonal NOX trading 
program operated from 2009 through 2014, the original CSAPR seasonal 
NOX trading program started operating in 2015,\22\ and the 
CSAPR Update trading program started operating in 2017.
---------------------------------------------------------------------------

    \17\ 70 FR 25162 (May 12, 2005) (SIP requirements); 71 FR 25328 
(Apr. 28, 2006) (parallel federal implementation plan requirements).
    \18\ North Carolina v. EPA, 531 F.3d 896 (D.C. Cir. 2008), 
modified on rehearing, 550 F.3d 1176 (D.C. Cir. 2008).
    \19\ 76 FR 48208 (Aug. 8, 2011); see also 76 FR 80760 (Dec. 27, 
2011) (adding seasonal NOX emissions reduction 
requirements for sources in five states), 79 FR 71663 (Dec. 3, 2014) 
(tolling implementation dates by three years).
    \20\ 81 FR 74504 (Oct. 26, 2016). Consolidated challenges to the 
CSAPR Update are pending in Wisconsin v. EPA, No. 16-1406 (D.C. Cir. 
appeal docketed Nov. 23, 2016).
    \21\ CAIR also established trading programs for sulfur dioxide 
(SO2) and annual NOX emissions designed to 
address the 1997 annual fine particulate matter (PM2.5) 
NAAQS. These additional trading programs were replaced under the 
original CSAPR by trading programs for SO2 and annual 
NOX emissions established to address both the 1997 annual 
PM2.5 NAAQS and the 2006 24-hour PM2.5 NAAQS.
    \22\ The original CSAPR seasonal NOX trading program 
remains in effect for sources in Georgia but after 2016 has not 
applied to sources in any state subject to the NOX SIP 
Call as amended.
---------------------------------------------------------------------------

    For purposes of this proposed action, the most important difference 
between the NBTP and its successor seasonal NOX trading 
programs concerns the types of sources participating in the various 
programs. As discussed above, the NBTP was designed to cover both large 
EGUs and large non-EGU boilers

[[Page 48756]]

and turbines. In contrast, by default the three successor trading 
programs have covered only units considered EGUs under those programs, 
which generally means all units that would be classified as 
NOX SIP Call large EGUs as well as a small subset of the 
units that would be classified as NOX SIP Call large non-EGU 
boilers and turbines.\23\ Under the CAIR seasonal NOX 
trading program, most NOX SIP Call states exercised an 
option to expand program applicability to include all their 
NOX SIP Call large non-EGU boilers and turbines,\24\ but the 
option was eliminated under the original CSAPR seasonal NOX 
trading program and no state has exercised the restored option made 
available under the CSAPR Update trading program.\25\ Consequently, at 
present most NOX SIP Call large non-EGU boilers and turbines 
do not participate in a successor trading program to the NBTP.
---------------------------------------------------------------------------

    \23\ For example, a unit qualifying as exempt from the Acid Rain 
Program under the provision for cogeneration units at 40 CFR 
72.6(b)(4) could be covered under the CAIR, original CSAPR, and 
CSAPR Update trading programs as an EGU. Under the NOX 
SIP Call as amended, such a unit would be classified as a large non-
EGU boiler or turbine.
    \24\ See 40 CFR 51.123(aa)(2)(i) and (ee)(1).
    \25\ See 40 CFR 52.38(b)(8)(ii) and (b)(9)(ii).
---------------------------------------------------------------------------

    The second relevant difference between the NBTP and its successor 
trading programs concerns the various programs' geographic areas of 
coverage. In each successive rulemaking to address states' good 
neighbor obligations, even in instances where the rulemakings concerned 
the same ozone NAAQS, other factors have changed, including the 
available data on air quality, emissions inventories, and potential 
emission control opportunities. Given different inputs to the analytic 
processes for the successive rulemakings, EPA's determinations 
regarding which upwind states must reduce emissions to address good 
neighbor obligations have differed as well. At present, EGUs in 
fourteen NOX SIP Call states participate in the CSAPR Update 
trading program.\26\ EGUs in the remaining seven NOX SIP 
Call jurisdictions do not currently participate in a successor trading 
program to the NBTP, although most such units are subject to other EPA 
programs with comparable part 75 monitoring requirements.\27\
---------------------------------------------------------------------------

    \26\ The CSAPR Update applies to EGUs in the NOX SIP 
Call states of Alabama, Illinois, Indiana, Kentucky, Maryland, 
Michigan, Missouri, New Jersey, New York, Ohio, Pennsylvania, 
Tennessee, Virginia, and West Virginia as well as eight additional 
states that were not subject to the NOX SIP Call as 
amended.
    \27\ EGUs in the NOX SIP Call jurisdictions of 
Connecticut, Delaware, Massachusetts, North Carolina, Rhode Island, 
South Carolina, and the District of Columbia are not subject to the 
CSAPR Update. Most NOX SIP Call EGUs in these 
jurisdictions are subject to the Acid Rain Program, and all 
NOX SIP Call EGUs in North Carolina and South Carolina 
participate in trading programs for SO2 and annual 
NOX emissions established under the original CSAPR.
---------------------------------------------------------------------------

    In the CAIR rulemaking, EPA amended the NOX SIP Call 
regulations both to provide that the NBTP would be discontinued 
coincident with implementation of the CAIR seasonal NOX 
trading program and to require states to adopt new control measures 
into their SIPs replacing the portions of their NOX SIP Call 
emissions reduction requirements that had been met through the 
NBTP.\28\ As discussed above, notwithstanding the discontinuation of 
the NBTP, the NOX SIP Call's requirements for enforceable 
mass emissions limits and Part 75 monitoring continue to apply to large 
EGUs and large non-EGU boilers and turbines in all affected states. 
Since the CAIR rulemaking, EPA has worked with NOX SIP Call 
states individually to assist them in revising their SIPs to meet these 
ongoing NOX SIP Call requirements, whether through use of 
the NBTP's successor trading programs (to the extent those options have 
been available) or through other replacement control measures.
---------------------------------------------------------------------------

    \28\ 40 CFR 51.121(r); see also 40 CFR 51.123(bb) and 
52.38(b)(10)(ii) (authorizing use of CAIR and CSAPR Update seasonal 
NOX trading programs as NBTP replacement control measures 
for large non-EGU boilers and turbines).
---------------------------------------------------------------------------

C. The NOX SIP Call's Contributions to Attainment of the NAAQS

    As described in section II.B., implementation of the NBTP began in 
2003 for the sources in some affected states and in 2004 for the 
sources in most remaining affected states, and the program operated 
through the 2008 ozone season. Between 2000 and 2004, seasonal 
NOX emissions from all sources participating in the NBTP 
\29\ fell from 1,256,237 tons to 609,029 tons, a decrease of over 50%, 
and by 2008, seasonal NOX emissions from these sources 
declined further to 481,420 tons.\30\ By comparison, the portions of 
the statewide seasonal NOX emissions budgets assigned to 
sources participating in the NBTP in all NOX SIP Call 
states--as indicated by the numbers of emission allowances available 
for allocation for the 2008 ozone season pursuant to states' SIPs--sum 
to 528,453 tons.\31\ EPA believes that the NOX SIP Call as 
implemented through the NBTP was an important driver of these emissions 
reductions.
---------------------------------------------------------------------------

    \29\ Small portions of these totals represent emissions and 
budget amounts for sources that participated in the NBTP pursuant to 
requirements or opt-in provisions in certain states' SIPs but that 
are not large EGUs or large non-EGU boilers or turbines subject to 
Sec.  51.121(i)(4). 2017 emissions for these types of sources are 
shown separately in Table 1 in section III.A. of this notice.
    \30\ See The NOX Budget Trading Program: 2008 
Emission, Compliance, and Market Analyses (July 2009) at 14, 
available in the docket for this proposed action.
    \31\ Id.
---------------------------------------------------------------------------

    Under CAA section 107(d)(3)(E), 42 U.S.C. 7407(d)(3)(E), 
redesignation of an area to attainment of a NAAQS requires a 
determination that the improvement in air quality is due to ``permanent 
and enforceable'' emissions reductions. At least 140 EPA final actions 
redesignating areas in 20 states to attainment with an ozone NAAQS or a 
PM2.5 NAAQS (because NOX is a precursor to 
PM2.5 as well as ozone) have relied in part on the Rule's 
emissions reductions.\32\ This includes actions redesignating areas to 
attainment with the 1997 ozone NAAQS, the 2008 ozone NAAQS, the 1997 
PM2.5 NAAQS, and the 2006 PM2.5 NAAQS. In 
response to legal challenges, multiple courts of appeals have held that 
the Rule's emissions reductions qualify as permanent and enforceable 
and therefore may be used to support redesignation actions.\33\
---------------------------------------------------------------------------

    \32\ See Redesignation Actions Relying on NOX SIP 
Call Emissions Reductions (August 2018), available in the docket for 
this proposed action.
    \33\ Sierra Club v. EPA, 774 F.3d 383, 397-99 (7th Cir. 2014) 
(holding that NOX SIP Call emissions reductions may be 
relied on as permanent and enforceable for purposes of 
redesignations); Sierra Club v. EPA, 793 F.3d 656, 665-68 (6th Cir. 
2015) (same, but vacating redesignations on other grounds).
---------------------------------------------------------------------------

    EPA has reinforced the permanence and enforceability of the Rule's 
emissions reductions by expressly requiring in the implementation rules 
for both the 1997 ozone NAAQS and the 2008 ozone NAAQS that, first, the 
NOX SIP Call in general and states' emissions budgets in 
particular will continue to apply after revocation of the previous 
ozone NAAQS and, second, any modifications to control requirements 
approved into a SIP pursuant to the Rule are subject to anti-
backsliding requirements under CAA section 110(l), 42 U.S.C. 
7410(l).\34\
---------------------------------------------------------------------------

    \34\ See 40 CFR 51.905(f) and 51.1105(e).
---------------------------------------------------------------------------

    In this action, to avoid any possible argument that the proposed 
changes would result in a lessening of permanence and enforceability 
that could threaten continued reliance on the NOX SIP Call's 
emissions reductions to support other actions, EPA is expressly not 
proposing to substantively amend--and is not reopening for substantive 
comment--the Rule's key provisions supporting these attributes. These 
key provisions include the statewide emissions budgets and general 
enforceability and monitoring

[[Page 48757]]

requirements as well as the requirements for enforceable limits on 
seasonal NOX mass emissions from large EGUs and large non-
EGU boilers and turbines. As discussed in section III.A., EPA believes 
that under current circumstances, the proposed amendment to allow 
states to establish alternate monitoring requirements for large EGUs 
and large non-EGU boilers and turbines does not undermine assurance 
that the Rule's required emissions reductions will continue to be 
achieved and therefore does not pose a risk to the permanence and 
enforceability of the emissions reductions.

III. Proposed Amendments to the NOX SIP Call Regulations

    This section describes the amendments being proposed as well as the 
rationales. In section III.A., EPA discusses a proposed amendment to 
allow states to revise their SIPs to establish monitoring requirements 
for large non-EGU boilers and turbines (and some large EGUs not subject 
to the Acid Rain Program or any CSAPR trading programs) other than Part 
75 monitoring requirements. This is the only amendment proposed in this 
action that would have a substantive impact on existing regulatory 
requirements.
    Section III.B. discusses a proposed amendment that would rescind 
the findings of good neighbor obligations with regard to the 1997 8-
hour ozone NAAQS that originally constituted a second basis for the 
NOX SIP Call. These findings have been subject to an 
indefinite stay by EPA since 2000, and all the NOX SIP 
Call's requirements as implemented rest independently on findings of 
good neighbor obligations with regard to the 1979 1-hour ozone NAAQS 
that would remain in place. The proposed rescission thus would have no 
substantive effect on the regulatory obligations faced either by states 
or by sources subject to the states' SIPs.
    Sections III.C., III.D., III.E., and III.F. discuss additional 
proposed amendments that would remove obsolete provisions or clarify 
the remaining NOX SIP Call regulations without substantively 
altering any existing regulatory requirements. Section III.C. addresses 
provisions relating to emissions budgets and emissions inventories, 
section III.D. addresses provisions relating to interstate emission 
allowance trading program options, and section III.E. addresses 
procedural provisions. Section III.F. identifies the locations of minor 
editorial revisions not covered in the other sections.

A. Emissions Monitoring Requirements

    Under Sec.  51.121(i)(4) of the existing NOX SIP Call 
regulations, where a state's SIP revision contains control measures for 
large EGUs or large non-EGU boilers and turbines, the SIP must also 
require part 75 monitoring for these types of sources. As discussed in 
section II.A., all NOX SIP Call states triggered this 
requirement by including control measures in their SIPs for these types 
of sources, and the requirement remains in effect despite the 
discontinuation of the NBTP after the 2008 ozone season. In this 
action, for the reasons discussed below, EPA proposes to amend the 
NOX SIP Call provision at Sec.  51.121(i)(4) to make the 
inclusion of part 75 monitoring requirements for these sources in SIPs 
optional rather than mandatory for NOX SIP Call purposes. 
The SIPs would still need to include some form of emissions monitoring 
requirements for these types of sources, consistent with the Rule's 
general enforceability and monitoring requirements at Sec.  
51.121(f)(1) and (i)(1), respectively, but states would no longer be 
required to satisfy these general Rule requirements specifically 
through the adoption of part 75 monitoring requirements.\35\ 
Finalization of this proposed amendment would not in itself eliminate 
part 75 monitoring requirements for any sources but would enable EPA to 
approve SIP submittals replacing these requirements with other forms of 
monitoring requirements.
---------------------------------------------------------------------------

    \35\ The proposed revision would not authorize states to create 
exceptions to any part 75 monitoring requirements that might apply 
to a source under a different legal authority.
---------------------------------------------------------------------------

    EPA originally established the condition that SIPs must include 
part 75 monitoring requirements based on determinations that, first, a 
requirement for mass emissions limits for large EGUs and large non-EGU 
boilers and turbines was feasible and provided the greatest assurance 
that the NOX SIP Call's required emissions reductions would 
be achieved, and second, part 75 monitoring was a feasible and cost-
effective way to ensure compliance with the mass emissions limits for 
these sources.\36\ (Part 75 monitoring requirements were also 
established independently as an essential element of the now-
discontinued NBTP, which like EPA's other emission allowance trading 
programs could function only with timely reporting of consistent, 
quality-assured mass emissions data by all participating units.) As 
noted in section II.C., to ensure that the NOX SIP Call's 
emissions reductions can continue to be relied on as permanent and 
enforceable for purposes of other actions, EPA is not proposing to 
amend the Rule's existing requirements regarding enforceable mass 
emissions limits for these sources. However, EPA believes that under 
current circumstances, allowing states to establish alternate 
monitoring requirements for large EGUs and large non-EGU boilers and 
turbines would not pose a risk to the permanence and enforceability of 
the Rule's emissions reductions.
---------------------------------------------------------------------------

    \36\ See 63 FR 57356, 57451-52.
---------------------------------------------------------------------------

    The first relevant current circumstance is the substantial margins 
by which all NOX SIP Call states are now complying with the 
portions of their statewide emissions budgets assigned to large EGUs 
and large non-EGU boilers and turbines. As shown in Table 1, in 2017, 
seasonal NOX emissions from sources that would have been 
subject to the NBTP across the region covered by the NOX SIP 
Call were approximately 200,000 tons, which is less than 40% of the sum 
of the relevant portions of the statewide final NOX budgets. 
Table 1 also shows that no state's emissions exceeded 71% of the 
relevant portion of its budget.\37\ These comparisons demonstrate that 
the Rule's required emissions reductions would continue to be achieved 
even with substantial increases in emissions from current levels. EPA 
views the possibility of such large increases as remote because of 
requirements under other state and federal environmental programs \38\ 
and changes to the fleet of affected sources since 2008.\39\
---------------------------------------------------------------------------

    \37\ 2017 emissions from Missouri sources were just over 70% of 
the relevant portion of the state's budget.
    \38\ For example, for the 11 states covered in their entirety 
under both programs--Illinois, Indiana, Kentucky, Maryland, New 
Jersey, New York, Ohio, Pennsylvania, Tennessee, Virginia, and West 
Virginia--EGU emissions budgets under the current CSAPR Update 
seasonal NOX trading program range from 17% to 66% of the 
portions of the respective states' NOX SIP Call emissions 
budgets based on EGU emissions. Compare 40 CFR 97.810(a) (CSAPR 
Update budgets) with 65 FR 11222, 11225 (Mar. 2, 2000) (EGU-based 
portions of NOX SIP Call budgets).
    \39\ For example, sources responsible for over 40% of 2008 
emissions reported under the NBTP have either ceased operation or 
switched from coal combustion to gas or oil combustion since 2008. 
See Post-2008 Changes to Units Reporting Under the NOX 
Budget Trading Program (August 2018), available in the docket for 
this proposed action.

[[Page 48758]]

                                         Table 1--2017 Emissions and Relevant Emissions Budget Amounts by State
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                           NOX emissions during the 2017 ozone season (tons) from:
                                                                    --------------------------------------------------------------------    Portion of
                                                                                         Other NBTP                                         statewide
                               State                                   NBTP sources    large EGUs and     Other NBTP                        emissions
                                                                     also subject to   large non- EGU  sources subject   Total for all   budget assigned
                                                                      Part 75 under     boilers and       to Part 75      NBTP sources   to NBTP sources
                                                                      other programs      turbines      under NSC SIPs                        (tons)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Alabama (part).....................................................            7,166            1,911                0            9,077           25,497
Connecticut........................................................              380               10               39              430            4,477
Delaware...........................................................              324              511                0              835            5,227
District of Columbia...............................................                0               20                0               20              233
Illinois...........................................................           13,038            1,493                0           14,531           35,557
Indiana............................................................           20,396            1,201              823           22,419           55,729
Kentucky...........................................................           19,978               75                0           20,053           36,109
Maryland...........................................................            2,422              516                0            2,939           15,466
Massachusetts......................................................              734              113               32              879           12,861
Michigan (part)....................................................           14,580              205                0           14,785           31,247
Missouri (part)....................................................            9,486                0                0            9,486           13,459
New Jersey.........................................................            1,646              310                0            1,956           13,022
New York...........................................................            4,062              941              611            5,614           41,385
North Carolina.....................................................           16,352            1,689                0           18,041           34,703
Ohio...............................................................           20,012              993                0           21,005           49,842
Pennsylvania.......................................................           13,616              837                0           14,453           50,843
Rhode Island.......................................................              193                0                0              193              936
South Carolina.....................................................            5,030            1,043                0            6,074           19,678
Tennessee..........................................................            7,785            2,350                0           10,135           31,480
Virginia...........................................................            7,462              589                0            8,051           21,195
West Virginia......................................................           18,187              276                0           18,463           29,507
                                                                    ------------------------------------------------------------------------------------
    Total..........................................................          182,849           15,084            1,505          199,438          528,453
--------------------------------------------------------------------------------------------------------------------------------------------------------
Data sources: Emissions data are from EPA's Air Markets Program Database, https://ampd.epa.gov/ampd. In a few cases where 2017 data are not available,
  the most recent available data are used instead. Budget data are from The NOX Budget Trading Program: 2008 Emission, Compliance, and Market Analyses
  (July 2009) at 14, available in the docket for this proposed action.

    The second relevant current circumstance is that even with the 
amendments proposed in this action, Part 75 monitoring requirements 
would remain in effect for most NOX SIP Call large EGUs 
pursuant to other regulatory requirements, including the Acid Rain 
Program and the CSAPR trading programs, and these large EGUs are 
responsible for most of the collective emissions of NOX SIP 
Call large EGUs and large non-EGU boilers and turbines. Table 1 shows 
the portions of the reported seasonal NOX emissions for each 
state reported by units that would continue to be subject to Part 75 
monitoring requirements even if the amendments proposed in this action 
are finalized and all states choose to revise their SIPs.\40\ As 
indicated in the table, the sources that would continue to report under 
Part 75 account for over 90% of the overall emissions. If the proposed 
amendments are finalized and a state chooses to revise its SIP to no 
longer require Part 75 monitoring for some sources, then under Sec.  
51.121(f)(1) and (i)(1)--which EPA is not proposing to amend--the SIP 
would still have to include provisions requiring all large EGUs and 
large non-EGU boilers and turbines subject to control measures for 
purposes of the NOX SIP Call to submit other forms of 
information on their seasonal NOX emissions sufficient to 
ensure compliance with the control measures. EPA believes that in the 
context of the substantial compliance margins discussed above, and 
given the continued availability of Part 75 monitoring data from 
sources responsible for most of the relevant emissions, emissions data 
from the remaining sources submitted pursuant to other forms of 
monitoring requirements can provide sufficient assurance that the 
Rule's overall required emissions reductions will continue to be 
achieved.
---------------------------------------------------------------------------

    \40\ Although the Acid Rain Program does not require units to 
report NOX mass emissions specifically, NOX 
mass emissions can be calculated from other Part 75 data that are 
required to be reported.
---------------------------------------------------------------------------

B. Good Neighbor Obligations Under the 1997 8-Hour Ozone NAAQS

    As discussed in section II.A., the NOX SIP Call as 
originally promulgated rested on findings of good neighbor obligations 
for affected states with respect to both the 1979 1-hour ozone NAAQS 
and the 1997 8-hour ozone NAAQS, but following an adverse D.C. Circuit 
decision, EPA amended the Rule to indefinitely stay the findings under 
the 1997 8-hour ozone NAAQS. In this action, EPA proposes to rescind as 
obsolete the stayed findings of good neighbor obligations under the 
1997 8-hour ozone NAAQS and to remove the corresponding NOX 
SIP Call regulatory provision at Sec.  51.121(a)(2) along with related 
language in other provisions, as further discussed below.
    Since the stay of the NOX SIP Call's findings of good 
neighbor obligations under the 1997 8-hour ozone NAAQS, EPA has 
addressed states' good neighbor obligations under this NAAQS in both 
the original CSAPR and the CSAPR Update,\41\ superseding the stayed 
findings and making it appropriate to rescind them, as proposed here. 
First, in the original CSAPR rulemaking, EPA either found no good 
neighbor obligation or quantified good neighbor requirements under the 
1997 8-hour ozone NAAQS for all states originally covered by the 
NOX SIP Call (including Georgia, Wisconsin, and the portions 
of Alabama, Michigan, and Missouri not covered by the NOX 
SIP Call as implemented following amendments), finding for some states 
that the

[[Page 48759]]

quantified emissions reduction requirements represented a full remedy 
for the states' good neighbor obligations and for other states that the 
quantified emissions reduction requirements might only partially 
address the states' good neighbor obligations.\42\ Then, after the D.C. 
Circuit remanded the CSAPR Phase 2 seasonal NOX budgets for 
several states,\43\ in the CSAPR Update EPA again evaluated states' 
good neighbor obligations with respect to the 1997 8-hour ozone NAAQS, 
determining that the states with remanded CSAPR seasonal NOX 
budgets no longer had good neighbor obligations under this NAAQS and 
that the remaining states' good neighbor obligations under this NAAQS 
were fully addressed by their CSAPR emissions reduction 
requirements.\44\ Thus, for each of the states subject to the stayed 
findings of good neighbor obligations with respect to the 1997 8-hour 
ozone NAAQS under the NOX SIP Call, upon further analysis 
using more recent data in the CSAPR and CSAPR Update rulemakings, EPA 
has determined that the state either has no good neighbor obligation 
under this NAAQS or that the state's obligation has been fully 
addressed through the state's CSAPR seasonal NOX emissions 
reduction requirements.
---------------------------------------------------------------------------

    \41\ EPA also addressed states' good neighbor obligations under 
the 1997 8-hour ozone NAAQS in CAIR, but as noted earlier the D.C. 
Circuit remanded CAIR to EPA for replacement.
    \42\ See 76 FR 48208, 48210.
    \43\ EME Homer City Generation, L.P. v. EPA, 795 F.3d 118, 138 
(D.C. Cir. 2015).
    \44\ See 81 FR 74504, 74523-26.
---------------------------------------------------------------------------

    In conjunction with the proposed rescission and removal of the 
findings discussed above, EPA also proposes to remove the regulatory 
provision at Sec.  51.121(q) staying the findings and to remove phrases 
in the provisions at Sec.  51.121(c)(1) and (c)(2) referencing the 1979 
1-hour ozone NAAQS solely to distinguish that NAAQS from the 1997 8-
hour ozone NAAQS. When the findings of good neighbor obligations under 
the 1997 8-hour ozone NAAQS are rescinded and removed from the 
regulations, the regulatory provision staying the findings will become 
obsolete. Similarly, the phrases distinguishing among multiple NAAQS 
will become superfluous once the regulations only contain language 
addressing a single NAAQS.

C. Emissions Budget and Emissions Inventory Provisions

    To simplify and clarify the regulations, EPA proposes to update the 
NOX SIP Call provisions describing the Rule's Phase I and 
Phase II emissions budgets and emissions reduction requirements at 
Sec.  51.121(e)(2)(i) and (e)(3) as well as related language in other 
provisions. EPA is also proposing to remove obsolete Rule provisions 
concerning the budgets and emissions inventories at Sec.  51.121(e)(4), 
(e)(5), and (g)(2)(ii) along with a related cross-reference. The 
proposed updates and removals would not alter any existing regulatory 
requirements.
    As discussed in section II.A., in response to a D.C. Circuit 
opinion remanding the Rule with respect to certain issues, EPA divided 
the Rule's overall emissions reduction requirements into two phases. As 
the first step in this phased approach, in April 2000 EPA sent letters 
to officials in each NOX SIP Call state identifying the 
portion of the state's overall emissions reduction requirement that was 
not implicated by the remanded issues and that should therefore be 
implemented in Phase I.\45\ The letters expressed each state's Phase I 
emissions reduction requirement in the form of a Phase I emissions 
budget that was computed as the state's projected 2007 emissions 
inventory minus the required Phase I emissions reduction. Then, to 
complete the phased approach, in April 2004 EPA finalized a rulemaking 
action determining for each covered state, after reconsideration of all 
remanded issues, the final overall emissions reduction requirement, the 
corresponding final budget, and the incremental difference between the 
Phase I budget and the final budget.\46\ In the 2004 action, the table 
of emissions budgets in Sec.  51.121(e)(2)(i) of the NOX SIP 
Call regulations was revised to show the amounts of the Rule's final 
emissions budgets. However, reflecting the 2004 amendments' focus on 
the Phase II requirements, EPA did not include the Phase I budgets in 
the regulatory text but instead added a new Sec.  51.121(e)(3) with a 
table showing the amounts of the required incremental Phase II 
emissions reductions.
---------------------------------------------------------------------------

    \45\ See Summary of EPA's Approach to the NOX SIP 
Call in Light of the March 3rd Court Decision (Apr. 11, 2000), 
available in the docket for this proposed action.
    \46\ 69 FR 21604, 21628-29.
---------------------------------------------------------------------------

    While the preamble of the 2004 action was clear about the nature of 
what was being determined in that action, when incorporating the 
amounts of the required incremental Phase II emissions reductions into 
the Rule's regulatory text, EPA mischaracterized the amounts as ``Phase 
II incremental budget'' amounts and as ``portions of'' the Phase II 
final budgets. To eliminate the mischaracterization, EPA proposes in 
this action to remove Sec.  51.121(e)(3) and in its place to add a 
column showing the amounts of the Phase I budgets to the existing table 
in Sec.  51.121(e)(2)(i) that already shows the amounts of the final 
budgets. The source for the proposed column of Phase I budget amounts 
is the same table in the preamble for the 2004 action that was the 
source for both the final budget amounts and the incremental Phase II 
emissions reduction amounts.\47\ Relatedly, EPA proposes to revise the 
definitions of ``Phase I SIP submission'' and ``Phase II SIP 
submission'' at Sec.  51.121(a)(3)(i) and (a)(3)(ii), distinguishing 
those terms according to the applicable budgets rather than according 
to the treatment of the mischaracterized incremental Phase II emissions 
reduction amounts. EPA also proposes to modify the provisions at Sec.  
51.121(b)(1) and (b)(1)(i) to refer to ``each SIP revision'' and ``the 
applicable budget'', respectively, reflecting the fact that most states 
ultimately made separate Phase I and Phase II SIP submissions 
addressing the Phase I and final budgets. Collectively, these proposed 
revisions would express the Rule's existing final requirements, as well 
as the Phase I requirements, more simply and clearly.
---------------------------------------------------------------------------

    \47\ 69 FR 21604, 21629 (Table 6). In the table, the incremental 
emissions reduction amount for each state is shown as the ``Phase II 
incremental difference'' between the state's Phase I and final 
budgets. Missouri is not included in the table because the state did 
not have a Phase I emissions reduction requirement or corresponding 
Phase I budget.
---------------------------------------------------------------------------

    In addition to the clarifying updates to the Rule provisions 
described above, EPA is proposing to remove as obsolete three other 
sets of provisions related to the NOX SIP Call budgets and 
projected 2007 emissions inventories: Sec.  51.121(e)(4), which 
addresses the compliance supplement pool; Sec.  51.121(e)(5), which 
sets out a time-limited process for submitting new data that could be 
used to revise the emissions inventories and budgets published as part 
of the original Rule; and Sec.  51.121(g)(2)(ii), which as originally 
promulgated showed the projected 2007 emissions inventory for each 
state by sector. A phrase in the provision at Sec.  51.121(g)(2)(i) 
referencing the emissions inventory table would also be removed.
    The Rule's compliance supplement pool provisions at Sec.  
51.121(e)(4) allowed each state to issue a certain quantity of credits 
beyond the state's budget that sources could use for compliance with 
emission control requirements. Credits were required to be issued no 
later than the commencement of control measures under the Rule for the 
state's sources and could be used for compliance only in the first two 
years of control measures. These deadlines have long passed, making the 
compliance

[[Page 48760]]

supplement pool credits and the provisions governing them obsolete.
    The Rule's provisions at Sec.  51.121(e)(5) allow for the 
submission of new data to be used to revise the original emissions 
inventories and budgets. The provisions include a February 1999 
deadline for such data to be submitted and an April 1999 deadline for 
EPA to act on the submitted data. Again, these deadlines have long 
passed, making the provisions governing the submission and use of such 
new data obsolete.
    As originally promulgated, the NOX SIP Call provision at 
Sec.  51.121(g)(2)(ii) presented a table of the projected 2007 
emissions inventories for each covered state by sector. The table's 
purpose was to serve as an input to states' required demonstrations 
that their SIP revisions would achieve sufficient emissions reductions 
to meet the Rule's requirements. In 1999 and 2000, EPA updated the 
state budgets and emissions inventories and amended the table,\48\ but 
when the Rule's budgets were amended for the final time in 2004, the 
table was not amended. The information in the table consequently does 
not correspond to the NOX SIP Call as implemented, most 
notably because it still includes information for Wisconsin and it 
includes information for the entire states of Alabama, Michigan, and 
Missouri instead of only the portions of the states subject to the Rule 
as amended in 2004.\49\ Because the preamble of the 2004 action does 
not include all data necessary to update the table, and because the 
table's intended purpose has already been fulfilled through EPA's 
approval of all required Phase I and Phase II SIP submissions, EPA 
considers it appropriate to remove Sec.  51.121(g)(2)(ii) as obsolete 
without replacement. Upon removal of the table, the phrase in Sec.  
51.121(g)(2)(i) referencing the table will also become obsolete, and 
that phrase would therefore be removed as well.
---------------------------------------------------------------------------

    \48\ The current table incorrectly presents the budget data from 
the 2000 action, not the ``base'' projected 2007 emissions inventory 
data from that action. See 65 FR 11222, 11225-26 (Tables 1 and 2).
    \49\ In 2008, EPA removed information for Georgia but did not 
otherwise update the table. 73 FR 21528, 21538.
---------------------------------------------------------------------------

D. Interstate Trading Program Options

    The NOX SIP Call regulations include two separate sets 
of provisions governing the potential use of interstate emission 
allowance trading programs as control measures in covered states' SIP 
revisions, one set at Sec.  51.121(b)(2) concerning the use of trading 
programs in general and one set at Sec.  51.121(p) concerning the use 
of the NBTP in particular. In this action, EPA is proposing to remove 
as obsolete both sets of provisions governing the potential use of 
trading programs and to remove or update references to those provisions 
in several other locations in the NOX SIP Call regulations 
and in the CSAPR regulations. EPA is also proposing to clarify the 
provision at Sec.  51.121(r)(2) setting forth the transition 
requirements applicable to states following discontinuation of the 
NBTP.
    As discussed in section II.B., EPA discontinued administration of 
the NBTP after the 2008 ozone season and has since replaced the 
program, for some states and types of sources, with successor seasonal 
NOX trading programs. The NBTP's discontinuation has made 
the NOX SIP Call provision at Sec.  51.121(p) governing use 
of the NBTP as a control measure obsolete, and removal of the obsolete 
provision would in turn make cross-references to it obsolete. 
Accordingly, EPA would remove certain cross-references to Sec.  
51.121(p) from the provisions at Sec.  51.121(r)(1) and Sec.  
51.122(c)(1)(ii) and would replace the remaining cross-references to 
Sec.  51.121(p) in the NOX SIP Call regulations at Sec.  
51.121(r)(1) and (r)(2) and in the CSAPR regulations at 40 CFR 
52.38(b)(8)(ii), (b)(8)(iii)(A)(2), (b)(9)(ii), and (b)(9)(iii)(A)(2) 
with cross-references to Sec.  51.121 more broadly.\50\
---------------------------------------------------------------------------

    \50\ Note that EPA is not proposing to remove the NBTP model 
rule at subparts A through I of 40 CFR part 96 in this action. The 
model rule is still incorporated by reference into several states' 
SIPs, where it continues to serve as a state-law mechanism 
implementing part 75 monitoring requirements for large non-EGU 
boilers and turbines even though the NBTP's allowance-related 
provisions are no longer being administered.
---------------------------------------------------------------------------

    The NOX SIP Call provisions at Sec.  51.121(b)(2) also 
authorize the use of interstate emission allowance trading programs 
other than the NBTP as control measures to address states' emissions 
reduction requirements under the Rule if the trading programs meet 
certain criteria. In theory, after the NBTP was discontinued, states 
could have elected to establish one or more alternate interstate 
trading programs under Sec.  51.121(b)(2) to replace the NBTP for any 
sources not covered by the NBTP's successor trading programs,\51\ but 
no states chose to do so. Further, recent emissions of large EGUs and 
large non-EGU boilers and turbines in every NOX SIPCall 
state have been below the collective caps that the states adopted for 
these sources in their Phase I and Phase II SIP revisions, indicating 
that there is currently little or no need for a new interstate trading 
program to help these sources meet NOX SIP Call 
requirements. EPA is unaware of any current state interest in pursuing 
this option. Accordingly, EPA considers the provisions at Sec.  
51.121(b)(2) functionally obsolete and appropriate for removal. Removal 
of Sec.  51.121(b)(2) would make a reference to that provision in Sec.  
51.121(b)(1)(i) obsolete, and that reference therefore would also be 
removed.
---------------------------------------------------------------------------

    \51\ The option for states to meet their ongoing NOX 
SIP Call requirements for large non-EGU boilers and turbines by 
expanding applicability under the CSAPR Update trading program is 
independently authorized under the CSAPR regulations at 40 CFR 
52.38(b)(10)(ii) rather than under Sec.  51.121(b)(2). Similarly, 
the former option to rely on the CAIR seasonal NOX 
trading program for this purpose was independently authorized under 
the CAIR regulations.
---------------------------------------------------------------------------

    In the CAIR rulemaking, besides adding a provision at Sec.  
51.121(r)(1) discontinuing the NBTP upon implementation of the CAIR 
seasonal NOX trading program, EPA also added a provision at 
Sec.  51.121(r)(2) establishing transition requirements for states. The 
basic requirement of Sec.  51.121(r)(2) is that each NOX SIP 
Call state must adopt replacement control measures into its SIP to 
achieve the same portion of the state's required emissions reductions 
under the Rule as the state originally projected the NBTP would 
achieve. As originally promulgated, the provision included an exception 
for instances where a state relied on the CAIR seasonal NOX 
trading program for this purpose. Because the original CSAPR seasonal 
NOX trading program did not provide an option to expand 
applicability to cover former NBTP large non-EGU boilers and turbines, 
in the original CSAPR rulemaking EPA amended the exception at Sec.  
51.121(r)(2) to indicate that the option to rely on the CAIR seasonal 
NOX trading program was expiring and necessarily did not 
indicate the existence of a new replacement option. In the CSAPR Update 
rulemaking, although a new replacement option was created in the CSAPR 
Update regulations authorizing reliance on the new trading program to 
meet NOX SIP Call obligations for large non-EGU boilers and 
turbines, EPA neglected to amend the exception language in Sec.  
51.121(r)(2) to reference the existence of the new replacement option.
    As noted above, in this action EPA would update obsolete cross-
references to Sec.  51.121(p) in both Sec.  51.121(r)(1) and (r)(2). 
EPA also proposes to update the post-NBTP transition provision at Sec.  
51.121(r)(2) in two further respects. First, as a replacement for the 
obsolete cross-reference identifying the terminated option to rely on 
the CAIR seasonal NOX trading program to fill gaps created 
by NBTP discontinuation, a new cross-reference identifying the

[[Page 48761]]

current option to rely on the CSAPR Update trading program for this 
purpose would be added. This revision would not create a new option--
because the option to rely on the CSAPR Update is already authorized 
under the CSAPR regulations--but it would clarify the NOX 
SIP Call regulations. Second, Sec.  51.121(r)(2) would be revised to 
expressly apply where a state's SIP ``includes or included'' trading 
program provisions to achieve the required emissions reductions. The 
purpose of this proposed revision is to eliminate any possible mistaken 
inference that a state's obligation to maintain NOX SIP Call 
emission controls might be contingent on whether its SIP currently 
includes trading program provisions and to reinforce that the Rule's 
emissions reductions are permanent and enforceable, as they must be to 
support other EPA actions. Again, this revision would not alter any 
existing regulatory requirements but would clarify the regulations.

E. Procedural Provisions

    EPA proposes to remove as obsolete a provision of the 
NOX SIP Call regulations setting forth certain procedural 
requirements for SIP submissions under the Rule. Currently, the Rule's 
requirements at Sec.  51.121(d) include (1) submission deadlines for 
Phase I and Phase II SIP submissions, (2) a requirement that 
submissions satisfy the general criteria for completeness in appendix V 
to 40 CFR part 51, and (3) a requirement that submissions be made in 
the form of five paper copies. The submission deadlines are obsolete 
because all required Phase I and Phase II SIP submissions have been 
made, and the requirement for five paper copies is obsolete because EPA 
now allows electronic SIP submissions. Any future SIP submissions under 
the Rule--such as submissions taking advantage of the more flexible 
monitoring requirements proposed in this action--would be subject to 40 
CFR 51.103(a), a provision of EPA's general SIP regulations that 
requires SIP submissions to conform to the completeness criteria in 
appendix V and also identifies the current electronic and paper SIP 
submission options. Removal of Sec.  51.121(d) therefore would clarify 
the regulations by removing the obsolete requirement for five paper 
copies and would not create any gap in procedural requirements for any 
future SIP submissions under the Rule.

F. Editorial Revisions

    EPA also proposes to make non-substantive, solely editorial 
revisions to several provisions of the NOX SIP Call 
regulations beyond those already discussed. One revision would replace 
the full-text definition of ``fossil fuel-fired'' at Sec.  51.121(i)(5) 
with a cross-reference to an identical definition at Sec.  
51.121(f)(3). In addition, minor revisions would be made to Sec.  
51.121(b)(1)(ii), (e)(2)(ii)(B), (e)(2)(ii)(E), (f)(2)(i)(B), 
(f)(2)(ii), (h), (i)(2), (i)(3), (l)(1), (l)(2), (m), (n), and (o) and 
the section heading. The proposed revisions would not alter any 
regulatory requirements and would generally improve clarity by reducing 
redundancy, standardizing terminology, and correcting various editorial 
errors.

IV. Impacts of the Proposed Amendments

    The proposed amendments would not change any of the NOX 
SIP Call's existing regulatory requirements related to statewide 
emissions budgets or enforceable mass emissions limits for large EGUs 
and large non-EGU boilers and turbines. Accordingly, EPA expects that 
the amendments, if finalized, would have no impact on emissions or air 
quality.
    The only amendment proposed in this action that would substantively 
alter existing regulatory requirements is the proposal to allow states 
to revise their SIPs to establish monitoring requirements for large 
non-EGU boilers and turbines (and some large EGUs not subject to the 
Acid Rain Program or any CSAPR trading programs) other than part 75 
monitoring requirements. Because states, not EPA, would decide whether 
to revise the monitoring requirements in their SIPs and because EPA 
lacks complete information on the remaining monitoring requirements 
that the sources would face, it is currently not possible to predict 
the amount of monitoring cost reductions that would occur if this 
proposed rule is finalized. However, EPA expects that at least some 
affected states would revise their SIPs and at least some sources would 
experience reductions in monitoring costs.
    The potential cost reduction opportunity for any given unit in a 
state that chooses to revise its SIP would depend on which of the 
various monitoring methodologies allowed under part 75 the unit 
currently uses and what other state and federal monitoring requirements 
the unit would still face, including monitoring requirements adopted in 
the state's SIP to replace the part 75 monitoring requirements. EPA's 
records indicate that currently there are approximately 310 large EGUs 
and large non-EGU boilers and turbines that are subject to part 75 
monitoring requirements pursuant to the existing NOX SIP 
Call requirement at Sec.  51.121(i)(4) and that are not also subject to 
comparable part 75 monitoring requirements under the Acid Rain Program 
or a CSAPR trading program. According to the part 75 monitoring plans 
submitted for these units,\52\ approximately 90 units use monitoring 
methodologies involving continuous emission monitoring systems (CEMS) 
to measure both stack gas flow rate and the concentrations of certain 
gases in the effluent gas stream, approximately 140 units use 
methodologies involving gas concentration CEMS but not stack gas flow 
rate CEMS, and approximately 80 units use non-CEMS methodologies.\53\ 
As a result of the amendments proposed in this action, some of the 230 
units currently using CEMS may ultimately be able to discontinue use of 
stack gas flow rate CEMS, gas concentration CEMS, or both, to the 
extent that the units do not face similar monitoring requirements under 
other state or federal regulations, possibly including, but not limited 
to, the replacement monitoring requirements established by states for 
NOX SIP Call purposes. Discontinuing usage of one or both 
types of CEMS has the potential to result in reductions in overall 
monitoring costs. Further, even if a unit remains subject to 
requirements to use some type of CEMS under other regulations, the 
specific CEMS-related requirements under the other regulations may 
entail lower costs than the specific CEMS-related requirements under 
part 75.\54\
---------------------------------------------------------------------------

    \52\ The monitoring plans are available at https://www.epa.gov/airmarkets/monitoring-plans-part-75-sources.
    \53\ Under part 75, options to use alternatives to stack gas 
flow rate CEMS are available to almost all units that combust only 
gaseous and liquid fuels, and options to use alternatives to gas 
concentration CEMS for measuring NOX emissions are 
available to any such units whose utilization rates or mass 
emissions fall below specified maximum limits. See 40 CFR 
75.19(a)(1), section 1.1 of appendix D to 40 CFR part 75, and 
section 1.1 of appendix E to 40 CFR part 75; see also 40 CFR 72.2 
(definitions of ``gas-fired'', ``oil-fired'', and ``peaking unit'').
    \54\ For example, other regulations may require less extensive 
data reporting or less comprehensive quality-assurance testing than 
would be required under part 75.
---------------------------------------------------------------------------

    With respect to the 80 units that are subject to part 75 monitoring 
requirements pursuant to the existing NOX SIP Call 
requirement at Sec.  51.121(i)(4), that are not also subject to 
comparable part 75 monitoring requirements under the Acid Rain Program 
or a CSAPR trading program, and that already use non-CEMS methodologies 
under Part 75, EPA expects that these units generally would experience 
little or no reduction in monitoring costs resulting from the

[[Page 48762]]

amendments proposed in this action. Similarly, the proposed amendments 
would not lead to any reduction in monitoring costs for units that 
would remain subject to Part 75 monitoring requirements under the Acid 
Rain Program or a CSAPR trading program. The proposed amendments also 
would not lead to any reduction in monitoring costs for units that 
formerly participated in the NBTP under states' SIPs but that are not 
large EGUs or large non-EGU boilers or turbines subject to the existing 
NOX SIP Call requirement at Sec.  51.121(i)(4),\55\ because 
the existing NOX SIP Call regulations do not prevent states 
from revising their SIPs to end Part 75 monitoring requirements for 
these sources even without the proposed amendments.
---------------------------------------------------------------------------

    \55\ According to EPA's records, currently there are 
approximately 130 such units, of which approximately 110 units 
already use non-CEMS methodologies under Part 75.
---------------------------------------------------------------------------

V. Request for Comment

    EPA requests comment on the proposed amendment discussed in section 
III.A. to revise the provision at 40 CFR 51.121(i)(4) to allow states 
to establish monitoring requirements for large EGUs and large non-EGU 
boilers and turbines in their SIPs other than Part 75 monitoring 
requirements.
    EPA believes the proposed amendments discussed in sections III.B. 
through III.F., if finalized, would not substantively alter existing 
regulatory requirements, and EPA is not reopening the provisions 
discussed in these sections (or any related provisions) for substantive 
comment. With respect to these proposed amendments, EPA requests and 
will accept comment solely on whether the provisions proposed for 
removal as obsolete in fact are obsolete and on whether the proposed 
clarifications in fact achieve clarification.
    EPA is expressly not reopening for comment any provisions of the 
existing NOX SIP Call regulations except the provisions that 
are proposed to be amended as discussed in section III of this 
proposal.\56\
---------------------------------------------------------------------------

    \56\ Regulatory findings and requirements that EPA is not 
proposing to substantively amend and that are not being reopened for 
substantive comment include (but are not limited to) the findings of 
good neighbor obligations with respect to the 1979 1-hour ozone 
NAAQS, the requirements for SIPs to contain control measures 
addressing these obligations, the final NOX budgets, the 
requirement for enforceable limits on seasonal NOX mass 
emissions for large EGUs and large non-EGUs where states have 
included control measures for these types of sources in their SIPs, 
the requirement for states to adopt replacement control measures 
into their SIPs to achieve the emissions reductions formerly 
projected to be achieved by the NBTP, and the general requirements 
for enforceability and for monitoring of the status of compliance 
with the control measures adopted.
---------------------------------------------------------------------------

VI. Statutory and Executive Order Reviews

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

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

    This action is not a significant regulatory action and was 
therefore not submitted to OMB for review.

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

    This action is expected to be an Executive Order 13771 deregulatory 
action. This proposed rule is expected to provide meaningful burden 
reduction by allowing states to establish lower-cost monitoring 
requirements in their SIPs for some sources as alternatives to Part 75 
monitoring requirements. However, because states, not EPA, would decide 
whether to revise the monitoring requirements in their SIPs and because 
EPA lacks complete information on the remaining monitoring requirements 
that the sources would face, EPA cannot currently predict the amount of 
monitoring cost reductions that would occur if this proposed rule is 
finalized. A qualitative discussion of the possible monitoring cost 
reductions can be found in EPA's analysis of the potential impacts 
associated with this action in section IV.

C. Paperwork Reduction Act

    This action does not impose any new information collection burden 
under the Paperwork Reduction Act. OMB has previously approved the 
information collection activities contained in the existing regulations 
and has assigned OMB control number 2060-0445. However, to reflect the 
proposed amendment allowing states to establish potentially lower-cost 
monitoring requirements for some sources as alternatives to the current 
Part 75 monitoring requirements, EPA is submitting an information 
collection request (ICR) renewal to OMB. The ICR document prepared by 
EPA, which has been assigned EPA ICR number 1857.08, can be found in 
the docket for this proposed action. Like the current ICR, the ICR 
renewal reflects the information collection burden and costs associated 
with Part 75 monitoring requirements for sources that are subject to 
Part 75 monitoring requirements under the SIP revisions addressing 
states' NOX SIP Call obligations and that are not subject to 
Part 75 monitoring requirements under another program (i.e., the Acid 
Rain Program or a CSAPR trading program). The ICR renewal is generally 
unchanged from the current ICR except that the renewal reflects 
projected decreases in the numbers of sources that would perform Part 
75 monitoring for NOX SIP Call purposes based on an 
assumption (made only for purposes of estimating information collection 
burden and costs for the ICR renewal) that, over the course of the 3-
year renewal period, some states will revise their SIPs to replace Part 
75 monitoring requirements for some sources with lower-cost monitoring 
requirements. As under the current ICR, all information collected from 
sources under the ICR renewal will be treated as public information.
    Respondents/affected entities: Fossil fuel-fired boilers and 
stationary combustion turbines that have heat input capacities greater 
than 250 mmBtu/hr or serve electricity generators with nameplate 
capacities greater than 25 MW and that are not subject to Part 75 
monitoring requirements under another program.
    Respondents' obligation to respond: Mandatory if elected by the 
state (40 CFR 51.121(i)(4) as proposed to be amended).
    Estimated number of respondents: 340 (average over 2019-2021 
renewal period).
    Frequency of response: Quarterly, occasionally.
    Total estimated burden: 131,945 hours (per year). Burden is defined 
at 5 CFR 1320.3(b).
    Total estimated cost: $19,143,004 (per year), includes $8,256,087 
annualized capital or operation & maintenance costs.
    An agency may not conduct or sponsor, and a person is not required 
to respond to, a collection of information unless it displays a 
currently valid OMB control number. The OMB control numbers for EPA's 
regulations in 40 CFR are listed in 40 CFR part 9.
    Submit your comments on the Agency's need for this information, the 
accuracy of the provided burden estimates and any suggested methods for 
minimizing respondent burden to EPA using the docket identified at the 
beginning of this rule. You may also send your ICR-related comments to 
OMB's Office of Information and Regulatory Affairs via email to 
[email protected], Attention: Desk Officer for EPA. Since OMB 
is required to make a decision concerning

[[Page 48763]]

the ICR between 30 and 60 days after receipt, OMB must receive comments 
no later than October 29, 2018. EPA will respond to any ICR-related 
comments in the final rule.

D. Regulatory Flexibility Act

    I certify that this action will not have a significant economic 
impact on a substantial number of small entities under the Regulatory 
Flexibility Act. In making this determination, the impact of concern is 
any significant adverse economic impact on small entities. An agency 
may certify that a rule will not have a significant economic impact on 
a substantial number of small entities if the rule relieves regulatory 
burden, has no net burden, or otherwise has a positive economic effect 
on the small entities subject to the rule. This action does not 
directly regulate any entity, but would simply allow states to 
establish potentially lower-cost monitoring requirements for some 
sources and generally streamline existing regulations. EPA has 
therefore concluded that this action will either relieve or have no net 
regulatory burden for all affected small entities.

E. Unfunded Mandates Reform Act

    This action does not contain any unfunded mandate as described in 
the Unfunded Mandates Reform Act, 2 U.S.C. 1531-1538, and does not 
significantly or uniquely affect small governments. The action imposes 
no enforceable duty on any state, local, or tribal governments or the 
private sector. This action would simply allow states to establish 
potentially lower-cost monitoring requirements for some sources and 
generally streamline existing regulations.

F. Executive Order 13132: Federalism

    This action does not have federalism implications. It will not have 
substantial direct effects on the states, on the relationship between 
the national government and the states, or on the distribution of power 
and responsibilities among the various levels of government. This 
action would simply allow states to establish potentially lower-cost 
monitoring requirements for some sources and generally streamline 
existing regulations.

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

    This action does not have tribal implications as specified in 
Executive Order 13175. It will not have substantial direct effects on 
tribal governments, on the relationship between the federal government 
and Indian tribes, or on the distribution of power and responsibilities 
between the federal government and Indian tribes. This action would 
simply allow states to establish potentially lower-cost monitoring 
requirements for some sources and generally streamline existing 
regulations. Thus, Executive Order 13175 does not apply to this action.

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

    EPA interprets Executive Order 13045 as applying only to those 
regulatory actions that concern environmental health or safety risks 
that EPA has reason to believe may disproportionately affect children, 
per the definition of ``covered regulatory action'' in section 2-202 of 
the Executive Order. This action is not subject to Executive Order 
13045 because it would simply allow states to establish potentially 
lower-cost monitoring requirements for some sources and generally 
streamline existing regulations.

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

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

J. National Technology Transfer Advancement Act

    This rulemaking does not involve technical standards.

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

    EPA believes that this action is not subject to Executive Order 
12898 because it does not establish an environmental health or safety 
standard. This action would simply allow states to establish 
potentially lower-cost monitoring requirements for some sources and 
generally streamline existing regulations. Consistent with Executive 
Order 12898 and EPA's environmental justice policies, EPA considered 
effects on low-income populations, minority populations, and indigenous 
peoples while developing the original NOX SIP Call. The 
process and results of that consideration are described in the 
Regulatory Impact Analysis for the NOX SIP Call.

List of Subjects

40 CFR Part 51

    Environmental protection, Administrative practice and procedure, 
Air pollution control, Incorporation by reference, Intergovernmental 
relations, Nitrogen oxides, Ozone, Particulate matter, Reporting and 
recordkeeping requirements, Sulfur dioxide.

40 CFR Part 52

    Environmental protection, Administrative practice and procedure, 
Air pollution control, Incorporation by reference, Intergovernmental 
relations, Nitrogen oxides, Ozone, Particulate matter, Reporting and 
recordkeeping requirements, Sulfur dioxide.

    Dated: September 13, 2018.
Andrew R. Wheeler,
Acting Administrator.

    For the reasons stated in the preamble, parts 51 and 52 of chapter 
I of title 40 of the Code of Federal Regulations are proposed to be 
amended as follows:

PART 51--REQUIREMENTS FOR PREPARATION, ADOPTION, AND SUBMITTAL OF 
IMPLEMENTATION PLANS

0
 1. The authority citation for part 51 continues to read as follows:

    Authority: 23 U.S.C. 101; 42 U.S.C. 7401-7671q.

Subpart G--Control Strategy

Sec.  51.121  [Amended]

0
 2. Section 51.121 is amended by:
0
a. Revising the section heading;
0
b. Removing and reserving paragraph (a)(2);
0
c. Revising paragraph (a)(3);
0
d. In paragraph (b)(1) introductory text, removing the text ``section, 
the'' and adding in its place the text ``section, each'';
0
e. In paragraph (b)(1)(i), adding the word ``applicable'' before the 
word ``budget'', and removing the text ``(except as provided in 
paragraph (b)(2) of this section),'' and adding in its place a 
semicolon ``;'';
0
f. In paragraph (b)(1)(ii), removing the period and adding in its place 
the text ``; and'';
0
g. Removing and reserving paragraph (b)(2);
0
h. In paragraph (c)(1), removing the text ``With respect to the 1-hour 
ozone NAAQS:'';
0
i. In paragraph (c)(2), removing the text ``With respect to the 1-hour 
ozone NAAQS, the portions of Missouri, Michigan, and Alabama'' and 
adding in

[[Page 48764]]

its place the text ``The portions of Alabama, Michigan, and Missouri'';
0
j. Removing and reserving paragraph (d);
0
k. Revising paragraph (e)(2)(i);
0
l. In paragraph (e)(2)(ii)(B), removing the text ``De Kalb,'' and 
adding in its place the text ``DeKalb,'';
0
m. In paragraph (e)(2)(ii)(E), removing the text ``St. Genevieve,'', 
and after the text ``St. Louis City,'' adding the text ``Ste. 
Genevieve,'';
0
n. Removing paragraphs (e)(3), (e)(4), and (e)(5);
0
o. In paragraph (f)(2)(i)(B), removing the text ``mass NOX'' 
and adding in its place the text ``NOX mass'';
0
 p. In paragraph (f)(2)(ii), removing the text ``(b)(1) (i)'' and 
adding in its place the text ``(b)(1)(i)'';
0
 q. In paragraph (g)(2)(i), removing the text ``as set forth for the 
State in paragraph (g)(2)(ii) of this section,'';
0
r. Removing and reserving paragraph (g)(2)(ii);
0
s. In paragraphs (h), (i)(2), and (i)(3), removing the words ``of this 
part'';
0
t. Revising paragraphs (i)(4) and (i)(5);
0
u. In paragraphs (l)(1), (l)(2), and (m), removing the words ``of this 
part'';
0
v. In paragraph (n), removing the text ``Sec.  52.31(c) of this part'' 
and adding in its place the text ``40 CFR 52.31(c)'', and removing the 
text ``Sec.  52.31 of this part.'' and adding in its place the text 
``40 CFR 52.31.'';
0
w. In paragraph (o), removing the words ``of this part'';
0
x. Removing and reserving paragraphs (p) and (q); and
0
y. Revising paragraph (r).
    The revisions read as follows:

Sec.  51.121   Findings and requirements for submission of State 
implementation plan revisions relating to emissions of nitrogen oxides.

    (a) * * *
    (3)(i) For purposes of this section, the term ``Phase I SIP 
submission'' means a SIP revision submitted by a State on or before 
October 30, 2000 in compliance with paragraph (b)(1)(ii) of this 
section to limit projected NOX emissions from sources in the 
relevant portion or all of the State, as applicable, to no more than 
the State's Phase I NOX budget under paragraph (e) of this 
section.
    (ii) For purposes of this section, the term ``Phase II SIP 
submission'' means a SIP revision submitted by a State in compliance 
with paragraph (b)(1)(ii) of this section to limit projected 
NOX emissions from sources in the relevant portion or all of 
the State, as applicable, to no more than the State's final 
NOX budget under paragraph (e) of this section.
* * * * *
    (e) * * *
    (2)(i) The State-by-State amounts of the Phase I and final 
NOX budgets, expressed in tons, are listed in Table 1 to 
Paragraph (e)(2)(i)--State NOX Budgets

            Table 1 to Paragraph (e)(2)(i)--State NOX Budgets
------------------------------------------------------------------------
                                              Phase I
                  State                       budget       Final  budget
------------------------------------------------------------------------
Alabama.................................         124,795         119,827
Connecticut.............................          42,891          42,850
Delaware................................          23,522          22,862
District of Columbia....................           6,658           6,657
Illinois................................         278,146         271,091
Indiana.................................         234,625         230,381
Kentucky................................         165,075         162,519
Maryland................................          82,727          81,947
Massachusetts...........................          85,871          84,848
Michigan................................         191,941         190,908
Missouri................................  ..............          61,406
New Jersey..............................          95,882          96,876
New York................................         241,981         240,322
North Carolina..........................         171,332         165,306
Ohio....................................         252,282         249,541
Pennsylvania............................         268,158         257,928
Rhode Island............................           9,570           9,378
South Carolina..........................         127,756         123,496
Tennessee...............................         201,163         198,286
Virginia................................         186,689         180,521
West Virginia...........................          85,045          83,921
------------------------------------------------------------------------

* * * * *
    (i) * * *
    (4) If the revision contains measures to control fossil fuel-fired 
NOX sources serving electric generators with a nameplate 
capacity greater than 25 MWe or boilers, combustion turbines or 
combined cycle units with a maximum design heat input greater than 250 
mmBtu/hr, then the revision may require some or all such sources to 
comply with the monitoring, recordkeeping, and reporting provisions of 
40 CFR part 75, subpart H, provided that nothing in this section 
creates any exception to any requirements of 40 CFR part 75 that may 
apply to such a source under any other legal authority. A State 
requiring such compliance authorizes the Administrator to assist the 
State in implementing the revision by carrying out the functions of the 
Administrator under such part.
    (5) For purposes of paragraph (i)(4) of this section, the term 
``fossil fuel-fired'' has the meaning set forth in paragraph (f)(3) of 
this section.
* * * * *
    (r)(1) Notwithstanding any provisions of subparts A through I of 40 
CFR part 96 and any State's SIP to the contrary, with regard to any 
ozone season that occurs after September 30, 2008, the Administrator 
will not carry out any of the functions set forth for the Administrator 
in subparts A through I of 40 CFR part 96 or in any emissions trading 
program provisions in a State's SIP approved under this section.
    (2) Except as provided in 40 CFR 52.38(b)(10)(ii), a State whose 
SIP is approved as meeting the requirements of this section and that 
includes or included an emissions trading program approved under this 
section must revise the SIP to adopt control measures that satisfy the 
same portion of the State's NOX emissions reduction 
requirements under this section as the State projected

[[Page 48765]]

such emissions trading program would satisfy.

 Sec.  51.122  [Amended]

0
 3. Section 51.122 is amended by:
0
a. In paragraph (c)(1)(ii), removing the text ``pursuant to a trading 
program approved under Sec.  51.121(p) or''; and
0
b. In paragraph (e), italicizing the heading ``Approval of ozone season 
calculation by EPA.''.

PART 52--APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS

0
4. The authority citation for part 52 continues to read as follows:

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

Subpart A--General Provisions

Sec.  52.38  [Amended]

0
 5. In Sec.  52.38, paragraphs (b)(8)(ii), (b)(8)(iii)(A)(2), 
(b)(9)(ii), and (b)(9)(iii)(A)(2) are amended by removing the text 
``Sec.  51.121(p)'' and adding in its place the text ``Sec.  51.121''.

[FR Doc. 2018-20858 Filed 9-26-18; 8:45 am]
 BILLING CODE 6560-50-P