Document ID: EPA-R04-OAR-2019-0612-0001
Agency: epa
Document Type: Proposed Rule
Title: Air Quality State Implementation Plans; Approvalsand Promulgations: South Carolina; NOx SIP Call and Removal of CAIR
Posted Date: 2020-05-05T04:00Z

[Federal Register Volume 85, Number 87 (Tuesday, May 5, 2020)]
[Proposed Rules]
[Pages 26635-26641]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2020-08906]

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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 52

[EPA-R04-OAR-2019-0612; FRL-10008-55-Region 4]

Air Plan Approval; SC; NOX SIP Call and Removal of CAIR

AGENCY: Environmental Protection Agency (EPA).

ACTION: Proposed rule.

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SUMMARY: The Environmental Protection Agency (EPA) is proposing to 
approve State Implementation Plan (SIP) revisions submitted by the 
State of South Carolina through letters dated April 12, 2019, and July 
11, 2019 to establish a SIP-approved state control program to comply 
with the Nitrogen Oxides (NOX) SIP call obligations for 
electric generating units (EGUs) and

[[Page 26636]]

large non-EGUs. EPA is also proposing to remove the SIP-approved 
portions of the State's Clean Air Interstate Rule (CAIR) Program rules 
from the South Carolina SIP. In addition, EPA is proposing to approve 
into the SIP state regulations that establish an alternative monitoring 
option for certain sources.

DATES: Comments must be received on or before June 4, 2020.

ADDRESSES: Submit your comments, identified by Docket ID No. EPA-R04-
OAR-2019-0612 at 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 www2.epa.gov/dockets/commenting-epa-dockets.

FOR FURTHER INFORMATION CONTACT: Gobeail McKinley, Air Regulatory 
Management Section, Air Planning and Implementation Branch, Air and 
Radiation Division, U.S. Environmental Protection Agency, Region 4, 61 
Forsyth Street SW, Atlanta, Georgia 30303-8960. The telephone number is 
(404) 562-9230. Ms. McKinley can also be reached via electronic mail at 
mckinley.gobeail@epa.gov.

SUPPLEMENTARY INFORMATION: 

I. Background

    Under Clean Air Act (CAA or Act) section 110(a)(2)(D)(i)(I), which 
EPA has traditionally termed the good neighbor provision, states are 
required to address the interstate transport of air pollution. 
Specifically, the good neighbor provision requires that each state's 
implementation plan contain adequate provisions to prohibit air 
pollutant emissions from within the state that will significantly 
contribute to nonattainment of the national ambient air quality 
standards (NAAQS), or that will interfere with maintenance of the 
NAAQS, in any other state.
    In October 1998 (63 FR 57356), EPA finalized the ``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''). The NOX 
SIP Call required eastern states, including South Carolina, to submit 
SIPs that prohibit excessive emissions of ozone season NOX 
by implementing statewide emissions budgets.\1\ The NOX SIP 
Call addressed the good neighbor provision for the 1979 ozone NAAQS and 
was designed to mitigate the impact of transported NOX 
emissions, one of the precursors of ozone. EPA developed the 
NOX Budget Trading Program, an allowance trading program 
that states could adopt to meet their obligations under the 
NOX SIP Call. This trading program allowed the following 
sources to participate in a regional cap and trade program: Generally 
EGUs with capacity greater than 25 megawatts (MW); and large industrial 
non-EGUs, such as boilers and combustion turbines, with a rated heat 
input greater than 250 million British thermal units per hour (MMBtu/
hr). The NOX SIP Call also identified potential reductions 
from cement kilns and stationary internal combustion engines.
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    \1\ See 63 FR 57356 (October 27, 1998). As originally 
promulgated, the NOX SIP Call also addressed good 
neighbor obligations under the 1997 8-hour ozone NAAQS, but EPA 
subsequently stayed and later rescinded the rule's provisions with 
respect to that standard. See 65 FR 56245 (September 18, 2000); 84 
FR 8422 (March 8, 2019).
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    To comply with the NOX SIP Call requirements, South 
Carolina Department of Health and Environmental Control (SC DHEC) 
promulgated provisions at Regulation 61-62.96, Subparts A through I. 
EPA approved the provisions into the State's SIP in 2002.\2\ The 
provisions required EGUs and large non-EGUs in the State to participate 
in the NOX Budget Trading Program.
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    \2\ See 67 FR 43546 (June 28, 2002).
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    In 2005, EPA published CAIR, which required eastern states, 
including South Carolina, to submit SIPs that prohibited emissions 
consistent with ozone season (and annual) NOX budgets. See 
70 FR 25162 (May 12, 2005). CAIR addressed the good neighbor provision 
for the 1997 ozone NAAQS and 1997 fine particulate matter 
(PM2.5) NAAQS and was designed to mitigate the impact of 
transported NOX emissions with respect to not only ozone but 
also PM2.5. CAIR established several trading programs that 
EPA implemented through federal implementation plans (FIPs) for EGUs 
greater than 25 MW in each affected state, but not large non-EGUs; 
states could submit SIPs to replace the FIPs that achieved the required 
emission reductions from EGUs and/or other types of sources.\3\ When 
the CAIR trading program for ozone season NOX was 
implemented beginning in 2009, EPA discontinued administration of the 
NOX Budget Trading Program; however, the requirements of the 
NOX SIP Call continued to apply.
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    \3\ CAIR had separate trading programs for annual sulfur dioxide 
emissions, seasonal NOX emissions and annual 
NOX emissions.
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    On October 9, 2007, EPA approved an ``abbreviated SIP'' for South 
Carolina, consisting of regulations governing allocation of 
NOX allowances to EGUs for use in the trading programs 
established pursuant to CAIR, and related rules allowing additional 
sources to opt into the CAIR programs. See 72 FR 57209. The abbreviated 
SIP was implemented in conjunction with a FIP for South Carolina that 
specified requirements for emissions monitoring, permit provisions, and 
other elements of CAIR programs.
    On October 16, 2009, EPA approved a ``full SIP'' for South 
Carolina, through which various CAIR implementation provisions became 
governed by State rules rather than federal rules.\4\ Consistent with 
CAIR's requirements, EPA approved a SIP revision in which South 
Carolina regulations: (1) Sunsetted its NOX Budget Trading 
Program requirements, (2) removed NOX SIP Call 
implementation requirements (i.e., South Carolina Regulation 61-62.96, 
Subparts A through I, ``Nitrogen Oxides (NOX) Budget 
Program''), and (3) incorporated CAIR (i.e., South Carolina Regulation 
61- 62.96, Subparts AA through II, AAA through III, and AAAA through 
IIII, ``Nitrogen Oxides (NOX) and Sulfur Dioxide 
(SO2) Budget Trading Program''). See 74 FR 53167 (October 
16, 2009). Participation of EGUs in the CAIR ozone season 
NOX trading program addressed the State's obligation under 
the NOX SIP Call for those units, and South Carolina also 
chose to require non-EGUs subject to the NOX SIP Call to 
participate in the same CAIR trading program. In this manner, South 
Carolina's CAIR rules incorporated into the SIP addressed the State's 
obligations under the NOX SIP Call with respect to both EGUs 
and non-EGUs.
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    \4\ See 74 FR 53167.
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    The United States Court of Appeals for the District of Columbia 
Circuit (D.C. Circuit) initially vacated CAIR in 2008, but ultimately 
remanded the rule to EPA without vacatur to preserve the

[[Page 26637]]

environmental benefits provided by CAIR. See North Carolina v. EPA, 531 
F.3d 896, modified on rehearing, 550 F.3d 1176 (D.C. Cir. 2008). The 
ruling allowed CAIR to remain in effect temporarily until a replacement 
rule consistent with the court's opinion was developed. While EPA 
worked on developing a replacement rule, the CAIR program continued to 
be implemented with the NOX annual and ozone season trading 
programs beginning in 2009 and the SO2 annual trading 
program beginning in 2010.
    Following on the D.C. Circuit's remand of CAIR, EPA promulgated the 
Cross-State Air Pollution Rule (CSAPR) to replace CAIR and address the 
good neighbor provisions for the 1997 ozone NAAQS, the 1997 
PM2.5 NAAQS, and the 2006 PM2.5 NAAQS. See 76 FR 
48208 (August 8, 2011). Through FIPs, CSAPR required EGUs in eastern 
states, including South Carolina, to meet annual and ozone season 
NOX emission budgets and annual SO2 emission 
budgets implemented through new trading programs. Implementation of 
CSAPR began in January 1, 2015.\5\ CSAPR also contained provisions that 
would sunset CAIR-related obligations on a schedule coordinated with 
the implementation of the CSAPR compliance requirements. Participation 
by a state's EGUs in the CSAPR trading program for ozone season 
NOX generally addressed the state's obligation under the 
NOX SIP Call for EGUs. CSAPR did not initially contain 
provisions allowing states to incorporate large non-EGUs into that 
trading program to meet the requirements of the NOX SIP Call 
for non-EGUs. EPA also stopped administering CAIR trading programs with 
respect to emissions occurring after December 31, 2014.\6\
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    \5\ See 79 FR 71663 (December 3, 2014) and 81 FR 13275 (March 
14, 2016).
    \6\ See 79 FR 71663 (December 3, 2014) and 81 FR 13275 (March 
14, 2016).
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    After litigation that reached the Supreme Court, the D.C. Circuit 
generally upheld CSAPR but remanded several state budgets to EPA for 
reconsideration, including the Phase 2 ozone season NOX 
budget for South Carolina. EME Homer City Generation, L.P. v. EPA, 795 
F.3d 118, 129-30 (D.C. Cir. 2015). EPA addressed the remanded ozone 
season NOX budgets in the CSAPR Update, which also partially 
addressed eastern states' good neighbor obligations for the 2008 ozone 
NAAQS. See 81 FR 74504 (October 26, 2016). The air quality modeling for 
the CSAPR Update projected that South Carolina would not contribute 
significantly to nonattainment or interfere with maintenance in 
downwind areas for either the 1997 ozone NAAQS or the 2008 ozone NAAQS 
as of 2017, and the EGUs in the state therefore are no longer subject 
to a NOX ozone season trading program under either CSAPR or 
the CSAPR Update.\7\ The CSAPR Update also reestablished an option for 
most states to meet their ongoing obligations for non-EGUs under the 
NOX SIP Call by including the units in the CSAPR Update 
trading program, but since South Carolina's EGUs do not participate in 
that trading program, the option is not available to South Carolina. 
Because South Carolina's EGUs and non-EGUs no longer participate in any 
CSAPR or CSAPR Update trading program for ozone season NOX 
emissions, the NOX SIP Call regulations at 40 CFR 
51.121(r)(2) as well as anti-backsliding provisions at 40 CFR 51.905(f) 
and 40 CFR 51.1105(e) require these sources to maintain compliance with 
NOX SIP Call requirements in some other way.
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    \7\ In the CSAPR Update, EPA relieved EGUs in South Carolina 
from the obligation to participate in the original CSAPR 
NOX ozone season trading program for purposes of 
addressing the good neighbor requirements for the 1997 ozone NAAQS 
and did not require the EGUs to participate in the new CSAPR Update 
trading program for purposes of addressing the 2008 ozone NAAQS. See 
40 CFR 52.38(b)(2)(ii)-(iii). EGUs in South Carolina remain subject 
to CSAPR state trading programs for annual NOX and 
SO2 emissions for purposes of addressing the 
PM2.5 NAAQS under the state trading program rules 
codified in South Carolina regulation 61-62.97 that were adopted 
into the State's SIP. See 82 FR 47936. EPA acknowledges the D.C. 
Circuit's decision in Wisconsin v. EPA, 938 F.3d 303 (Sept. 13, 
2019), remanding the CSAPR Update with respect to the adequacy of 
the rulemaking to address the good neighbor obligations with respect 
to the 2008 ozone NAAQS; however, the court's decision does not 
address the determinations made in the CSAPR Update regarding 
state's obligations with respect to the 1997 ozone NAAQS as those 
determinations were not challenged in the course of the litigation.
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    Under 40 CFR 51.121(i)(4) of the NOX SIP Call 
regulations as originally promulgated, where a state's SIP contains 
control measures for EGUs and large non-EGUs, the SIP must also require 
these sources to monitor emissions according to the provisions of 40 
CFR part 75, which generally entails the use of continuous emission 
monitoring systems (CEMS). South Carolina triggered this requirement by 
including control measures in their SIP for these types of sources, and 
the requirement has remained in effect despite the discontinuation of 
the NOX Budget Trading Program after the 2008 ozone season. 
On March 8, 2019, EPA revised some of the regulations that were 
originally promulgated in 1998 to implement the NOX SIP 
Call.\8\ The revision gave states covered by the NOX SIP 
Call greater flexibility concerning the form of the NOX 
emissions monitoring requirements that the states must include in their 
SIPs for certain emissions sources. The revision amends 40 CFR 
51.121(i)(4) to make Part 75 monitoring, recordkeeping, and reporting 
optional, such that SIPs may establish alternative monitoring 
requirements for NOX SIP Call budget units that meet the 
general requirements of 40 CFR 51.121(f)(1) and (i)(1). Under the 
updated provision, a state's implementation plan would still need to 
include some form of emissions monitoring requirements for these types 
of sources, consistent with the NOX SIP Call'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 NOX SIP Call requirements specifically through 
the adoption of 40 CFR part 75 monitoring requirements.
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    \8\ See ``Emissions Monitoring Provisions in State 
Implementation Plans Required Under the NOX SIP Call,'' 
84 FR 8422.
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II. Why is EPA proposing these actions?

    SC DHEC's April 12, 2019, and July 11, 2019 \9\ letters request 
that EPA update South Carolina's SIP to reflect the reinstated 
NOX SIP Call requirements at Regulation 61-62, ``Air 
Pollution Control Regulations and Standards,'' provide additional 
monitoring flexibilities for certain units subject to the State's 
NOX SIP Call regulations, and remove CAIR requirements. 
Additionally, the July 11, 2019 submission includes a demonstration 
under CAA section 110(l) intended to show that the April 12, 2019 SIP 
revision does not interfere with any applicable CAA requirements. As 
discussed further below, EPA has reviewed these submittals, 
preliminarily finds them consistent with the CAA and regulations 
governing the NOX SIP Call, and is proposing to approve 
them, incorporate the NOX SIP call regulations into the 
State's SIP, and remove the CAIR regulations from the SIP.
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    \9\ This submission also includes amended regulations which are 
not part of the federally-approved SIP and are not addressed in this 
document such as: Amended Regulation 61-62.61, ``South Carolina 
Designated Facility Plan and New Source Performance Standards;'' 
amended Regulation 61-62.63, ``National Emission Standards for 
Hazardous Air Pollutants (``NESHAP'') for Source Categories;'' 
amended Regulation 61-62.68, ``Chemical Accident Prevention 
Provisions;'' and amended Regulation 61-62.70, ``Title V Operating 
Permit Program.''

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[[Page 26638]]

III. Analysis of South Carolina's Submittals

    South Carolina's submittals request EPA approve revisions to the 
State's SIP that: (1) Address the State's ongoing NOX SIP 
Call obligations for existing and new large non-EGUs and EGUs by 
reinstating applicable portions of the State's original NOX 
SIP Call regulations at South Carolina Regulation 61-62.96, Subparts A 
through I; (2) rescind CAIR regulations at South Carolina Regulations 
61-62.96, Subparts AA through II, AAA through III, and AAAA through 
IIII; and (3) adopt an alternative monitoring option for certain large 
non-EGUs at South Carolina Regulation 61-62.96, Subpart H, Section 
96.70. Specifically, SC DHEC updated the reinstated regulations to make 
the portion of the budget assigned to large non-EGUs and EGUs under the 
NOX Budget Trading Program enforceable without an allowance 
trading mechanism (i.e., rescinded portions of its NOX 
Budget Trading Program regulations pertaining to individual unit 
allowance allocations and trading). Also included in the regulations 
are provisions that require continued monitoring and reporting of ozone 
season NOX mass emissions under 40 CFR part 75, with the 
following exception. Specifically, the regulations provide any 
NOX SIP Call budget units that (1) are not required by 40 
CFR 51.121, South Carolina Regulation 61-62.97, or other regulation to 
comply with part 75 and (2) are subject to new source performance 
standards (NSPS) under 40 CFR part 60, subpart D or subpart Db, the 
option to instead monitor and report their ozone season NOX 
mass emissions in accordance with the applicable NSPS subpart.\10\
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    \10\ South Carolina adopted this alternative monitoring and 
reporting option to be consistent with the NOX SIP Call 
revision. See 84 FR 8422.
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1. Revisions Related to the NOX SIP Call

    SC DHEC has revised Regulation 61-62 to address the NOX 
SIP Call's requirements with respect to existing and new large EGUs and 
large non-EGUs, and has requested EPA approve these revisions into the 
SIP. EPA proposes to find that South Carolina's revised rules at 
Regulation 61-62.96, Subparts A through I, ``Nitrogen Oxides 
(NOX) Budget Program'' are consistent with South Carolina's 
obligation to demonstrate continued compliance with NOX SIP 
Call requirements for large EGUs and large non-EGUs and EPA's 
discontinuation of the trading program under the NOX SIP 
Call. Under the ongoing requirements of the NOX SIP Call, 
the South Carolina SIP must: (1) Include enforceable control measures 
for ozone season NOX mass emissions from existing and new 
large EGUs and large non-EGUs, and (2) require those sources to monitor 
and report ozone season NOX emissions. See 40 CFR 
51.121(f)(2) and (i).
a. NOX SIP Call
    As discussed above, the State regulations addressing the 
NOX SIP Call were formerly established at South Carolina 
Regulation 61-62.96, Subparts A through I, ``Nitrogen Oxides 
(NOX) Budget Program'' and South Carolina Regulation 61-
62.99, ``Nitrogen Oxides (NOX) Budget Program Requirements 
for Stationary Sources Not in the Trading Program'' (i.e., cement 
kilns). The requirements under South Carolina Regulation 61-62.96 
affect EGUs and non-EGUs. South Carolina Regulation 61-62.96, 
``NOX Budget Trading Program'' initially had nine subparts: 
Subpart A--NOX Budget Trading Program General Provisions; 
Subpart B--Authorized Account Representative for NOX Budget 
Sources; Subpart C--Permits; Subpart D--Compliance Certification; 
Subpart E--NOX Allowance Allocations; Subpart F--
NOX Allowance Tracking System; Subpart G--NOX 
Allowance Transfers; Subpart H--Monitoring and Reporting; and Subpart 
I--Individual Unit Opt-ins. Because EPA discontinued administration of 
the NOX Budget trading program in 2009 in coordination with 
the start of CAIR implementation, the NOX Budget trading 
program can no longer be implemented. Consistent with CAIR's 
provisions, South Carolina revised certain portions of South Carolina 
Regulation 61-62.96 to reflect CAIR annual NOX, annual 
SO2 and ozone season NOX emissions budget trading 
program requirements. This revision removed South Carolina's 
NOX Budget Program, Regulation 61-62.96, Subparts A through 
I, and the NOX SIP Call requirements for EGUs were addressed 
by South Carolina's CAIR NOX Ozone Season Program, 
Regulations 61-62.96, Subparts AAAA through IIII. Further, as noted 
above, the State exercised its option to include non-EGUs from the 
State's NOX Budget Trading Program in the CAIR 
NOX Ozone Season Trading Program.
    If approved into the SIP, the April 12, 2019, SIP submittal will 
reinstate portions of South Carolina Regulation 61-62.96 to address 
NOX SIP Call requirements with the new South Carolina 
Regulation, ``Nitrogen Oxides (NOX) Budget Program.'' 
Specifically, the submittal reinstates previously repealed Subparts A 
through I, including the applicable NOX SIP Call model rule 
provisions from 40 CFR part 96, with amendments reflecting the 
discontinuation of EPA's NOX SIP Call trading program and 
other changes as necessary. The new and reinstated NOX SIP 
Call regulation includes provisions to ensure that the State's EGUs and 
large non-EGUs will continue to satisfy NOX SIP Call 
requirements. South Carolina Regulation 61-62.96.40 sets the State's 
EGU ozone season budget at 16,199 tons per year (tpy) and large non-EGU 
ozone season budget at 3,479 tpy. It specifies that collective 
emissions from all EGUs and all large non-EGUs may not exceed their 
respective budgets during each control period. Regulations 61-62.96.6 
and 61-62.96.70 ensure continued monitoring and reporting of 
NOX emissions from covered units in accordance with 40 CFR 
51.121(i). Also, SC DHEC commits in its submission to conduct an annual 
review of its emission inventory data for both EGUs and large non-EGUs, 
including emissions from any applicable new units, to verify the 
NOX SIP Call EGU and large non-EGU ozone-season 
NOX emission budgets have not been exceeded.\11\
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    \11\ By September 30 of each year, SC DHEC will conduct an 
annual review of actual NOX emissions from all covered 
EGUs and large non-EGUs during the previous control period, 
including any new units, to ensure that the total emissions remain 
below the ozone season NOX budgets.
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    Section 61-62.96.70 of the South Carolina's reinstated 
NOX SIP Call regulation requires all owners and operators of 
covered NOX budget units to implement a monitoring and 
reporting system necessary to attribute ozone season NOX 
mass emissions to each unit in accordance with 40 CFR part 75.\12\ In 
addition, the State regulation allows flexibility for a NOX 
budget unit that (1) is not required by 40 CFR 51.121, South Carolina 
Regulation 61-62.97, or other regulation to comply with Part 75, and 
(2) is subject to Subpart D or Subpart Db of 40 CFR part 60, to instead 
monitor and report ozone season NOX mass emissions in 
accordance with Subpart D or Subpart Db, as applicable. Additional 
information regarding increased flexibility in monitoring is discussed 
in section III.1.b.
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    \12\ SC DHEC states that all of South Carolina's EGUs must 
continue Part 75 monitoring and reporting pursuant to applicable 
CSAPR requirements. See 81 FR 74583 (October 26, 2016). In addition, 
SC DHEC states that any affected boiler that is not subject to 
Subpart D or Db (due to grandfathering or otherwise) must continue 
to comply with Part 75 monitoring requirements.
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    Lastly, SC DHEC includes several administrative changes in its 
revised regulation. In South Carolina's original NOX SIP 
Call regulation, SC DHEC

[[Page 26639]]

excluded Standard Industrial Classification (SIC) codes 4911 and 4931 
in Section 96.4(a)(1)(i) from the NOX Budget Program. The 
July 11, 2019 SIP revision contains a list of all affected EGUs and 
large non-EGUs covered under the NOX SIP Call and clarifies 
its intention for the regulation to apply, as originally applied, to 
EGU and large non-EGU units listed in its CAA section 110(l) analysis. 
SC DHEC further clarified that it interprets the language in Section 
96.4(b)(4) such that a unit would lose an exemption under 69.4(b) 
(i.e., an exemption to the applicability of 61-62.96 Nitrogen Oxides 
(NOX) Budget Program based on fuel use and operating hour 
limitations) if it fails to comply with restrictions on fuel use or 
operating hours. Further, SC DHEC states that the exemption in Section 
96.4(b)(2)(ii) is not retroactive to the beginning of the ozone season 
if a source takes an emission limit during a particular ozone season.
    EPA proposes to find that, as revised, South Carolina Regulation 
61-62.96 meets the State's ongoing obligations under the NOX 
SIP Call. Specifically, EPA proposes to find that the revised rules 
meet the requirement under 40 CFR 51.121(f)(2) for enforceable limits 
on the subject units' collective emissions of ozone season 
NOX mass emissions. In the next section, EPA discusses South 
Carolina's revisions to meet the requirements under 40 CFR 51.121(f)(1) 
and (i)(1) for monitoring sufficient to ensure compliance with those 
limits.
b. Revisions Related to NOX SIP Call Monitoring
    As discussed above, Section 61-62.96.70 of South Carolina's 
reinstated NOX SIP Call regulation requires all owners and 
operators of covered NOX budget units to implement a 
monitoring and reporting system necessary to attribute ozone season 
NOX mass emissions to each unit in accordance with 40 CFR 
part 75 with the following exception. The regulation provides any South 
Carolina NOX SIP Call budget units that (1) are not required 
by 40 CFR 51.121, South Carolina Regulation 61-62.97, or other 
regulation to comply with Part 75 and (2) are subject to new source 
performance standards (NSPS) under 40 CFR part 60, subpart D or subpart 
Db, the option to instead monitor and report their ozone season 
NOX mass emissions in accordance with the applicable NSPS 
subpart.\13\ The monitoring requirements for each source will be 
specified in each source's NOX SIP Call permit condition. 
More specifically, SC DHEC will require facilities with large non-EGUs 
requesting the alternative monitoring to calculate the NOX 
mass emissions (in tons) for each ozone season using NOX 
emission rate data obtained in accordance with the applicable NSPS 
subpart and to report the total to SC DHEC no later than March 31 
following that ozone season. The reporting time period aligns with 
annual emissions inventory reporting as required by South Carolina 
Regulation 61-62.1, Section III(B)(1). The NOX emission rate 
would be calculated from Part 60 Continuous Emission Monitoring System 
(CEMS) measurements using Method 19 in Appendix A to 40 CFR part 60.
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    \13\ Those state sources otherwise required to comply with Part 
75 monitoring requirements (including all covered EGUs) will 
continue to do so.
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    In the July 11, 2019 SIP submittal, South Carolina provided an 
analysis to demonstrate that the monitoring flexibilities comply with 
CAA section 110(l). CAA section 110(l) provides that EPA cannot approve 
a SIP revision if the revision would interfere with any applicable 
requirement concerning attainment or reasonable further progress (RFP), 
or any other applicable requirement of the CAA. Additionally, section 
110(l) makes clear that each SIP revision is subject to the 
requirements of section 110(l). EPA generally considers whether the SIP 
revision would worsen, preserve, or improve the status quo in air 
quality.
    EPA does not anticipate emissions increases from the revisions to 
the South Carolina SIP a result of the alternative monitoring 
flexibilities. Several of the original large non-EGU sources have shut 
down and the remaining existing facilities, through compliance with 
federal permit restrictions, have combined potentials-to-emit that are 
well below the NOX SIP Call budget levels. The large non-EGU 
ozone season emissions have been low relative to the State's 
NOX SIP Call budget.\14\ For example, as indicated in EPA's 
NOX SIP Call amendment proposal, total 2017 emissions from 
NOX SIP Call budget units not otherwise subject to Part 75 
represent only 5.3 percent of South Carolina's NOX SIP Call 
annual emission budget.\15\ With the total potentials-to-emit for units 
covered by the NOX SIP Call well below the NOX 
SIP Call budgeted levels, SC DHEC notes that the preexisting 
NOX SIP Call budgets and Part 75 monitoring and reporting 
requirements have not themselves been a key factor in limiting 
emissions, and EPA believes that the budgets or the Part 75 monitoring 
and reporting requirements are not limiting emissions from affected 
units. SC DHEC also cites to the small amount of emissions attributable 
to sources that will be able to use the additional flexibilities, as 
well as the general effectiveness of Part 60 monitoring. SC DHEC states 
the alternative Part 60 monitoring flexibility allowed under the 
reinstated NOX SIP Call provisions will not interfere with 
continued attainment of the NAAQS or any other applicable requirement 
of the CAA.
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    \14\ SC DHEC estimated that the maximum ozone-season emissions 
total from all 14 large non-EGU units, if operated for the entire 
ozone season, would be 2,419 tons, well below the 3,479 tpy budget.
    \15\ 82 FR 41620, 41621 (September 1, 2017).
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    EPA's analysis of South Carolina's regulations concerning 
monitoring to comply with the NOX SIP Call follows the 
requirements outlined in EPA's March 8, 2019 rule amending the 
NOX SIP Call's monitoring requirements at 40 CFR 
51.121(i)(4). In that rule, EPA observed that, under 40 CFR 51.121(i), 
the principal criterion for approval of monitoring and reporting 
requirements for purposes of the NOX SIP Call following the 
amendments would be that the requirements must be sufficient to 
determine whether sources are in compliance with the control measures 
adopted to achieve the required emissions reductions.\16\ EPA noted 
that for purposes of demonstrating the sufficiency of the monitoring 
and reporting requirements, a state generally would be able to cite the 
same types of data (e.g., data indicating substantial compliance 
margins) that EPA cited to support finalizing the amendments to the 
NOX SIP Call regulations.\17\ In addition, EPA pointed out 
the need to consider whether the regulation contains provisions to 
avoid gaps in required monitoring and whether any monitoring approach 
that uses emissions factors is designed to avoid any bias toward 
understatement of emissions.\18\
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    \16\ See 84 FR at 8428-29.
    \17\ Id. n.30.
    \18\ Id.
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    In this document, EPA proposes to find that, as revised, South 
Carolina Regulation 61-62.96 meets the State's ongoing obligations 
under the NOX SIP Call with respect to monitoring to ensure 
compliance with required limitations and proposes to approve the 
alternate monitoring approach described above into South Carolina's 
SIP. If finalized, South Carolina's adopted monitoring flexibility 
would be available only to those large non-EGU sources that are not 
otherwise required to continue Part 75 monitoring and reporting. EPA's 
review preliminarily

[[Page 26640]]

concludes that South Carolina's revised regulations are sufficient to 
determine whether sources are in compliance with the control measures 
adopted to achieve the required emissions reductions; South Carolina 
has cited to data indicating substantial compliance margins; South 
Carolina's regulations avoid gaps in required monitoring; and South 
Carolina's regulations do not use emissions factors for alternative 
monitoring. In addition, EPA agrees with SC DHEC's conclusion that, 
because the large non-EGUs' combined maximum allowable emissions are 
well below the NOX SIP Call budget, neither the 
NOX SIP Call nor the previous monitoring requirements have 
been driving current emission levels down. EPA therefore agrees that no 
increase in emissions will result from the added option to monitor and 
report under Part 60 in lieu of Part 75. Thus, EPA proposes to conclude 
that South Carolina's monitoring regulations are sufficient to provide 
adequate monitoring under the NOX SIP call and comply with 
40 CFR 51.121(f)(1) and (i). EPA also preliminarily concludes that 
South Carolina's monitoring regulations will not interfere with 
continued attainment of the NAAQS, RFP or any other applicable 
requirement of the Clean Air Act.

2. Removal of CAIR

    South Carolina's April 12, 2019 submission also seeks to remove the 
SIP-approved portions of the State trading program rules adopted to 
implement CAIR from South Carolina Regulation 61-62.96 Subparts AA 
through II, AAA through III, and AAAA through IIII. With regard to the 
annual programs, the State requests removal because the CAIR annual 
programs have been replaced by the CSAPR annual programs. With respect 
to the ozone season program, South Carolina's April 12, 2019 submission 
seeks to remove the SIP-approved portions of the State's trading 
program rules because, if approved, South Carolina's state control 
program would address outstanding NOX SIP Call requirements. 
Further, South Carolina's July 11, 2019 SIP submission contains a 
technical demonstration showing that no increase in NOX 
ozone season emissions is expected to result from the removal of CAIR 
because the combined potential to emit from covered sources remains 
below CAIR budget levels, and historical data shows that covered 
sources' emissions have remained well below budgeted levels.
    In this document, EPA proposes to approve the removal of these 
CAIR-related provisions from South Carolina's SIP. As explained above, 
the D.C. Circuit remanded CAIR to EPA in 2008, however, the court left 
CAIR in place while EPA worked to develop a new interstate transport 
rule. CSAPR was promulgated to respond to the court's concerns and to 
replace CAIR. CAIR was implemented through the 2014 compliance periods 
and was replaced by CSAPR on January 1, 2015. EPA promulgated 
regulations to sunset the CAIR trading programs and is no longer 
administering those trading programs, and the programs therefore can no 
longer be implemented for South Carolina sources. Further, EPA has 
reviewed South Carolina's demonstration and preliminarily agrees that 
no emissions increase is expected to result from removal of CAIR. In 
particular, ozone season NOX mass emissions data reported to 
EPA for South Carolina's large EGUs and large non-EGUs indicate that 
collective emissions have consistently been less than 10,000 tons in 
every year since 2012, well below the state's budgets for these units 
under both the NOX SIP Call and CAIR, indicating that the 
state's CAIR rules for ozone season NOX would not be driving 
current emission levels even if they were capable of implementation. 
EPA therefore preliminarily concludes that removal of CAIR from South 
Carolina's SIP will not result in any increase in emissions and 
therefore will not interfere with continued attainment of the NAAQS or 
any other applicable requirement of the Clean Air Act, and proposes to 
approve the removal of South Carolina's SIP provisions related to CAIR.

IV. Incorporation by Reference

    In this document, EPA is proposing to include in a final EPA rule 
regulatory text that includes incorporation by reference. In accordance 
with requirements of 1 CFR 51.5, EPA is proposing to incorporate by 
reference South Carolina Regulation 61-62.96 entitled, ``Nitrogen 
Oxides (NOX) Budget Program,'' effective January 25, 2019, 
which reinstates applicable portions of EPA's 40 CFR part 96 
NOX SIP Call regulations and establishes alternative 
emission monitoring requirements for certain units. Also, in this 
document, EPA is proposing to remove South Carolina Regulation 61-62.96 
Subparts AA through II, AAA through III, and AAAA through IIII 
entitled, ``Nitrogen Oxides (NOX) and Sulfur Dioxide 
(SO2) Budget Trading Program,'' from the South Carolina 
State Implementation Plan, which is incorporated by reference in 
accordance with the requirements of 1 CFR part 51. EPA has made, and 
will continue to make the State Implementation Plan generally available 
through www.regulations.gov and at the EPA Region 4 Office (please 
contact the person identified in the FOR FURTHER INFORMATION CONTACT 
section of this preamble for more information).

V. Proposed Actions

    EPA is proposing to approve South Carolina's SIP April 12, 2019 and 
July 11, 2019 SIP revisions and to incorporate Regulation 61-62.96 
entitled, ``Nitrogen Oxides (NOX) Budget Program,'' and 
Regulation 61-62.96, Subpart H, Section 96.70 into the SIP. In 
addition, EPA is proposing to remove the State's CAIR regulations at 
Regulation 61-62.96 Subparts AA through II, AAA through III, and AAAA 
through IIII entitled, ``Nitrogen Oxides (NOX) and Sulfur 
Dioxide (SO2) Budget Trading Program,'' from the SIP. EPA is 
proposing to conclude that these revisions will not interfere with 
attainment and maintenance of the NAAQS, RFP, or any other applicable 
requirement of the CAA.

VI. Statutory and Executive Order Reviews

    Under the CAA, the Administrator is required to approve a SIP 
submission that complies with the provisions of the CAA and applicable 
Federal regulations. 42 U.S.C. 7410(k); 40 CFR 52.02(a). Thus, in 
reviewing SIP submissions, EPA's role is to approve state choices, 
provided that they meet the criteria of the CAA. Accordingly, these 
actions merely propose to approve state law as meeting Federal 
requirements and do not impose additional requirements beyond those 
imposed by state law. For that reason, these proposed actions:
     Are not significant regulatory actions subject to review 
by the Office of Management and Budget under Executive Orders 12866 (58 
FR 51735, October 4, 1993) and 13563 (76 FR 3821, January 21, 2011);
     Are not an Executive Order 13771 (82 FR 9339, February 2, 
2017) regulatory actions because SIP approvals are exempted under 
Executive Order 12866;
     Do not impose information collection burdens under the 
provisions of the Paperwork Reduction Act (44 U.S.C. 3501 et seq.);
     Are certified as not having significant economic impacts 
on a substantial number of small entities under the Regulatory 
Flexibility Act (5 U.S.C. 601 et seq.);
     Do not contain any unfunded mandates or significantly or 
uniquely affect small governments, as described

[[Page 26641]]

in the Unfunded Mandates Reform Act of 1995 (Pub. L. 104-4);
     Do not have federalism implications as specified in 
Executive Order 13132 (64 FR 43255, August 10, 1999);
     Are not economically significant regulatory actions based 
on health or safety risks subject to Executive Order 13045 (62 FR 
19885, April 23, 1997);
     Are not significant regulatory actions subject to 
Executive Order 13211 (66 FR 28355, May 22, 2001);
     Are not subject to requirements of Section 12(d) of the 
National Technology Transfer and Advancement Act of 1995 (15 U.S.C. 272 
note) because application of those requirements would be inconsistent 
with the CAA; and
     Do not provide EPA with the discretionary authority to 
address, as appropriate, disproportionate human health or environmental 
effects, using practicable and legally permissible methods, under 
Executive Order 12898 (59 FR 7629, February 16, 1994).
    Because these actions merely approve state law as meeting Federal 
requirements and do not impose additional requirements beyond those 
imposed by state law, this proposed action for the State of South 
Carolina does not have Tribal implications as specified by Executive 
Order 13175 (65 FR 67249, November 9, 2000). Therefore, this action 
will not impose substantial direct costs on Tribal governments or 
preempt Trial law. The Catawba Indian Nation (CIN) Reservation is 
located within the boundary of York County, South Carolina. Pursuant to 
the Catawba Indian Claims Settlement Act, S.C. Code Ann. 27-16-120 
(Settlement Act), ``all state and local environmental laws and 
regulations apply to the [Catawba Indian Nation] and Reservation and 
are fully enforceable by all relevant state and local agencies and 
authorities.'' The CIN also retains authority to impose regulations 
applying higher environmental standards to the Reservation than those 
imposed by state law or local governing bodies, in accordance with the 
Settlement Act.

List of Subjects in 40 CFR Part 52

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

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

Mary Walker,
Regional Administrator, Region 4.
[FR Doc. 2020-08906 Filed 5-4-20; 8:45 am]
 BILLING CODE 6560-50-P