Document ID: EPA-R05-OAR-2015-0699-0010
Agency: epa
Document Type: Rule
Title: Final approval of the Ohio 2010 1-Hour SO2 NAAQS Nonattainment SIP for Lake County
Posted Date: 2019-02-14T05:00Z

[Federal Register Volume 84, Number 31 (Thursday, February 14, 2019)]
[Rules and Regulations]
[Pages 3986-3991]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2019-02210]

[[Page 3986]]

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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 52

[EPA-R05-OAR-2015-0699; FRL-9989-48-Region 5]

Air Plan Approval; Ohio; Attainment Plan for the Lake County 
SO2 Nonattainment Area

AGENCY: Environmental Protection Agency (EPA).

ACTION: Final rule.

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SUMMARY: The Environmental Protection Agency (EPA) is approving, under 
the Clean Air Act (CAA), Ohio's plan for attaining the 1-hour sulfur 
dioxide (SO2) primary national ambient air quality standard 
(NAAQS) in the Lake County SO2 nonattainment area. EPA 
proposed to approve Ohio's Lake County plan as a revision to Ohio's 
SO2 State Implementation Plan (SIP) on August 21, 2018. EPA 
received public comments on the proposed rulemaking and is providing 
responses to the comments below.

DATES: This final rule is effective on March 18, 2019.

ADDRESSES: EPA has established a docket for this action under Docket ID 
No. EPA-R05-OAR-2015-0699. All documents in the docket are listed on 
the www.regulations.gov website. Although listed in the index, some 
information is not publicly available, i.e., Confidential Business 
Information (CBI) or other information whose disclosure is restricted 
by statute. Certain other material, such as copyrighted material, is 
not placed on the internet and will be publicly available only in hard 
copy form. Publicly available docket materials are available either 
through www.regulations.gov or at the Environmental Protection Agency, 
Region 5, Air and Radiation Division, 77 West Jackson Boulevard, 
Chicago, Illinois 60604. This facility is open from 8:30 a.m. to 4:30 
p.m., Monday through Friday, excluding Federal holidays. We recommend 
that you telephone Mary Portanova, Environmental Engineer, at (312) 
353-5954 before visiting the Region 5 office.

FOR FURTHER INFORMATION CONTACT: Mary Portanova, Environmental 
Engineer, Control Strategies Section, Air Programs Branch (AR-18J), 
Environmental Protection Agency, Region 5, 77 West Jackson Boulevard, 
Chicago, Illinois 60604, (312) 353-5954, portanova.mary@epa.gov.

SUPPLEMENTARY INFORMATION: Throughout this document whenever ``we,'' 
``us,'' or ``our'' is used, we mean EPA. Ohio's nonattainment SIP 
submittal of April 3, 2015, supplemented on October 13, 2015 and on 
March 13, 2017, addressed Ohio's Lake County, Muskingum River, and 
Steubenville OH-WV SO2 nonattainment areas. This final 
action addresses only the Lake County portion of Ohio's nonattainment 
SIP submittal. The Muskingum River and Steubenville portions of Ohio's 
submittal will be addressed in future action.
    This Supplementary Information section is arranged as follows:

I. Background
II. Public Comments and EPA Responses
III. What action is EPA taking?
IV. Statutory and Executive Order Reviews

I. Background

    Lake County, Ohio, was designated nonattainment for the 2010 1-hour 
primary SO2 NAAQS on August 5, 2013 (78 FR 47191). As 
required by the CAA, Ohio developed a plan to provide for attainment of 
the SO2 NAAQS in Lake County. Ohio submitted its plan to EPA 
on April 3, 2015 and supplemented it on October 13, 2015, and on March 
13, 2017. On August 21, 2018 (83 FR 42235), EPA proposed to find that 
Ohio appropriately demonstrated that its plan will provide for 
attainment of the SO2 NAAQS in Lake County by the applicable 
attainment date and that the plan meets the other applicable 
requirements of the CAA.

II. Public Comments and EPA Responses

    The comment period on EPA's August 21, 2018 notice of proposed 
rulemaking (NPRM) closed on September 20, 2018. EPA received one 
adverse public comment from the Sierra Club and one public comment 
which was not relevant to the proposed action. The adverse comment and 
EPA's response are described below. In the following discussion, EPA 
will refer to the Sierra Club as ``the commenter.'' ``The Painesville 
plant'' refers to the Painesville Municipal Electric Plant in Lake 
County. The ``April 2014 guidance'' refers to EPA's April 23, 2014 
recommended guidance for meeting the statutory requirements in 
SO2 nonattainment area SIPs, entitled, ``Guidance for 1-Hour 
SO2 Nonattainment Area SIP Submissions,'' available at 
https://www.epa.gov/sites/production/files/2016-06/documents/20140423guidance_nonattainment_sip.pdf.
    Comment: The commenter stated that short-term exposure to 
SO2 for as little as five minutes has significant health 
impacts, and that EPA changed the SO2 NAAQS to a shorter-
term form to address these health impacts. The commenter said that 
emission limits with an averaging period longer than one hour are 
highly unlikely to be able to protect the 1-hour NAAQS. The commenter 
said that EPA cannot rely on a 30-day emission limit for the 
Painesville plant to assure compliance with a 1-hour air quality 
standard. The commenter believes that EPA should not approve Ohio's 
nonattainment plan until Ohio develops a 1-hour emission limit for the 
Painesville plant that protects public health.
    EPA Response: The health effects information provided by the 
commenter, which was addressed in EPA's promulgation of the 2010 
SO2 NAAQS, is not in dispute in this rulemaking. This 
rulemaking instead addresses whether Ohio's plan is adequate to meet 
the NAAQS.
    EPA disagrees with the commenter's statement that emission limits 
with an averaging period longer than one hour are highly unlikely to be 
able to protect the 1-hour NAAQS. EPA believes as a general matter that 
properly set longer term average limits are comparably effective in 
providing for attainment of the 1-hour SO2 standard as 1-
hour limits. EPA provided a more complete rationale for this belief in 
the August 21, 2018 NPRM for the Lake County SO2 SIP, 
including a summary of analyses described in EPA's guidance that 
support a conclusion that the distribution of emissions that can be 
expected in compliance with a properly set longer term average limit is 
likely to yield better overall air quality than constant hourly 
emissions set at a level that provides for attainment. EPA found that a 
longer term average limit which is comparably stringent to a short-term 
average limit is likely to yield comparable air quality; and that the 
net effect of allowing emissions variability over time but requiring a 
lower average emission level is that the resulting worst-case air 
quality is likely to be comparable to or better than the worst-case air 
quality resulting from the corresponding higher emission limit without 
variability.
    It is useful here to distinguish between exceedances and 
violations. The term ``exceedance,'' or ``exceedance of the level of 
the NAAQS,'' is used to mean a single occasion on which the ambient 
SO2 concentration exceeds 75 parts per billion (ppb). The 
term ``violation,'' in contrast, means that a sufficient number and 
magnitude of exceedances has occurred to violate the NAAQS, i.e., that 
the 3-year average of the 99th percentile daily maximum 1-

[[Page 3987]]

hour SO2 concentrations is above 75 ppb.
    Any accounting of whether a 30-day average limit provides for 
attainment must consider factors that reduce the likelihood of 
exceedances of the NAAQS level as well as factors that create risk of 
additional exceedances. To facilitate this analysis, EPA used the 
concept of a critical emission value (CEV) for the SO2-
emitting facilities which are being addressed in a nonattainment SIP. 
The CEV is the continuous 1-hour emission rate which is expected to 
provide for the average annual 99th percentile maximum daily 1-hour 
concentration to be at or below 75 ppb, which in a typical year means 
that fewer than four days have maximum hourly ambient SO2 
concentrations exceeding 75 ppb.
    EPA recognizes that a 30-day limit can allow occasions in which 
emissions exceed the CEV, and such occasions yield the possibility of 
exceedances of the NAAQS level occurring that would not be expected if 
emissions were always at the CEV. At the same time, the establishment 
of the 30-day limit below the CEV means that emissions must routinely 
be lower than they would be required to be with a 1-hour emission limit 
at the CEV. On those critical modeled days in which emissions at the 
CEV are expected to result in concentrations exceeding 75 ppb, 
emissions below the CEV may well result in concentrations below 75 ppb.
    Requiring emissions on average to be below the CEV introduces 
significant chances that emissions will be below the CEV on critical 
days, so that such a requirement creates significant chances that air 
quality would be better than 75 ppb on days that, with emissions at the 
CEV, would have exceeded 75 ppb.
    The August 21, 2018 NPRM provides an illustrative example of the 
effect that application of a limit with an averaging time longer than 1 
hour can have on air quality. This example illustrates both: (1) The 
possibility of elevated emissions (emissions above the CEV) causing 
exceedances of the NAAQS level not expected with emissions at or below 
the CEV and (2) the possibility that the requirement for routinely 
lower emissions would result in avoiding exceedances of the NAAQS level 
that would be expected with emissions at the CEV. In this example, 
moving from a 1-hour limit to a 30-day average limit results in one day 
that exceeds 75 ppb that would otherwise be below 75 ppb, one day that 
is below 75 ppb that would otherwise be above 75 ppb, and one day that 
is below 75 ppb that would otherwise be at 75 ppb. In net, the 99th 
percentile of the 30-day average limit scenario is lower than that of 
the 1-hour limit scenario, with a design value of 67.5 ppb rather than 
75 ppb. Stated more generally, this example illustrates several points: 
(1) The variations in emissions that are accounted for with a longer 
term average limit can yield higher concentrations on some days and 
lower concentrations on other days, as determined by the factors 
influencing dispersion on each day, (2) one must account for both 
possibilities, and (3) accounting for both effects can yield the 
conclusion that a properly set longer term average limit can provide as 
good or better air quality than allowing constant emissions at a higher 
level.
    The commenter does not address EPA's full rationale for concluding 
that properly set 30-day average limits are a suitable basis for 
providing for attainment of the 1-hour SO2 standard. 
Instead, the commenter merely notes the possibility that air quality 
could be worse with a 30-day average limit than with a 1-hour limit 
because the longer-term limit appears to allow emissions to exceed the 
level of an acceptable 1-hour limit. The commenter makes no 
acknowledgement of the possibility that a properly adjusted 30-day 
average limit can avoid some exceedances of the NAAQS level that would 
be expected to occur with emissions allowed always to be at the CEV. 
Consequently, the commenter does not acknowledge or address the 
occasions in which the longer-term limit requires better air quality, 
which is a key element of EPA's rationale for concluding that the net 
effect of limiting longer term average emissions to a downward adjusted 
level can be comparably effective in providing for attainment as 
limiting 1-hour emissions to the level of the CEV.
    EPA does not agree that in all cases it must disapprove plans which 
use longer-term limits, and instead require 1-hour emission limits. 
After reviewing Ohio's submittal, EPA finds that the limits established 
for the Painesville plant provide a suitable alternative to 
establishing 1-hour average emission limits for this source. Ohio's 
limits for the Painesville plant were developed in accordance with 
EPA's April 2014 guidance, with an appropriate downward adjustment from 
the CEV found in Ohio's modeling analysis. EPA is satisfied that the 
Painesville plant's 30-day emission limits are therefore comparable in 
stringency to the 1-hour CEV. The Painesville plant's boilers are also 
subject to a requirement for a reduction in coal sulfur content, a 
separate 24-hour cap on their total operating rate, and an additional 
restriction to ten percent of their annual capacity in accordance with 
the Limited Use definition in the Boiler MACT \1\ rule.
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    \1\ Information about the boiler MACT is available at https://www.epa.gov/stationary-sources-airpollution/industrial-commercial-and-institutional-boilers-and-process-heaters.
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    In addition, the 2015 closure of the FirstEnergy Generation, LLC, 
Eastlake Plant has provided additional SO2 emission 
reductions which were not credited in the Lake County modeling 
analysis. These reductions help supplement the effectiveness of Ohio's 
planned reductions at the Painesville plant to bring Lake County into 
attainment of the 2010 SO2 NAAQS and maintain the standards 
in future.
    EPA believes that Ohio's Lake County nonattainment plan as a whole 
is sufficient to protect and maintain the 2010 SO2 NAAQS.
    Comment: The commenter asserts that the limits are ``not comparable 
in stringency to the hourly emission rates modeled by Ohio in its 
attainment demonstration.''
    EPA Response: The commenter does not dispute EPA's rationale for 
concluding that Ohio's 30-day average limits for the Painesville plant 
are comparably stringent to 1-hour limits at the level Ohio modeled, 
nor does the commenter provide a basis for its assertion that Ohio's 
limits are not comparably stringent. EPA's guidance provides a 
recommended approach for determining the ratio between 30-day average 
levels and 1-hour levels, determined at the 99th percentile level, 
which yields an adjustment factor that seeks to quantify the effect of 
using the longer averaging time on the stringency of the limit and thus 
presumptively expresses the degree of adjustment to be applied to a 1-
hour emission limit to determine a comparably stringent 30-day average 
limit.
    EPA concurred with Ohio's decision to apply the national average of 
such adjustment factors, as given in Appendix D of EPA's April 2014 
guidance. In absence of a rationale for changing its views, EPA 
continues to believe that the 30-day average limits adopted by Ohio are 
comparably stringent to 1-hour limits at the level Ohio modeled.
    Comment: The commenter said that air quality conditions can be 
rendered unsafe by as few as four hours of elevated emissions over the 
course of the year, making an emission limit with an averaging period 
of longer than one hour unlikely to be able to protect this short-term 
standard. The commenter argued that spikes in emissions from the 
Painesville plant could cause short-term

[[Page 3988]]

elevations in ambient SO2 levels sufficient to violate the 
NAAQS while nonetheless averaging out over longer periods such that the 
30-day average permit limit is ``complied'' with.
    EPA Response: Again, proper accounting of the air quality 
consequences of applying a 30-day average limit cannot be limited to 
consideration of the possibility of additional exceedances of 75 ppb on 
days with emissions above the CEV; one must additionally consider the 
likelihood of effects in the other direction, i.e., that requiring 
lower emissions on average (and on most occasions) might result in 
avoiding exceedances of the NAAQS level that would occur with emissions 
at the CEV. As discussed above, the NPRM provides an example that 
illustrates this principle.
    In addition, for several reasons, EPA disagrees with the 
commenter's implication that any short-term occasion of elevated 
emissions (e.g., emissions above the CEV) creates an unacceptable risk 
of additional exceedances of the NAAQS level that would result in 
actual violation of the standard. First, the occurrence of an hour with 
emissions above the CEV is unlikely on its own to lead to a 
concentration above the level of the NAAQS. The CEV is identified as an 
emission level which will protect against NAAQS violations, considering 
the full range of local meteorological conditions. The analyses which 
identify the CEV show that ambient air concentrations would be well 
below exceedance levels in much of the modeling domain, and for most 
hours. Episodes of elevated emissions cause significantly elevated 
concentrations only on a limited number of days per year when 
meteorological conditions favor high concentrations. As a result, any 
single episode of elevated emissions cannot be assumed to cause an 
exceedance of 75 ppb, and in fact the risk of such an event, while 
nonzero, is quite low. Furthermore, even if multiple occurrences of 
elevated emissions do occur at times with meteorology conducive to high 
concentrations, these occasions are likely to involve different wind 
directions, resulting in the elevated concentrations occurring at 
different locations. Therefore, from the perspective that air quality 
is evaluated at individual locations, and a violation occurs only if 
any single location observes an excessive net number of exceedances, it 
is especially unlikely that isolated occurrences of elevated emissions 
(particularly in a scenario with emissions on most occasions being well 
below the CEV) would result in violations at any location.
    Second, EPA disagrees with the apparent view that any risk of an 
event in which elevated emissions causes otherwise unexpected 
exceedances of 75 ppb is an unacceptable risk. While use of a limit 
based on a long-term average increases the risk of elevated 
concentrations on a small number of days, the establishment of the 
limit at a reduced level means that most days will have a reduced risk 
of elevated concentrations. Since the pertinent question is whether 
Ohio's plan provides for attainment, EPA must address the net effect of 
applying a long-term average, not just considering those factors that 
increase the likelihood of exceedances of 75 ppb or just considering 
those factors that reduce the likelihood of such exceedances.
    Examining the net probabilities of elevated emissions occurring 
simultaneously with meteorology conducive to exceedances, and of 
reduced emissions occurring on occasions that would have experienced 
exceedances of the standard without that emission reduction, suggests 
that the net effects cannot be assessed without a complicated analysis. 
A more useful framework for considering these questions is to focus, 
for any particular location, on those hours where the meteorology is 
conducive to having high concentrations at that location. Consider, for 
example, the likely magnitude of emissions during the pertinent hours 
for a source that is complying with a long-term limit that reflects a 
30 percent downward adjustment. During the pertinent hours, the source 
is quite unlikely to be emitting more than the CEV (a probability on 
the order of 1 percent) and is much more likely to be emitting at or 
below 30 percent below the CEV. This perspective better frames the 
question of the net effect of having variable emissions occasionally 
exceeding the CEV but requiring emissions to average well below the CEV 
as compared to allowing emissions always to be at the CEV.
    EPA believes that if emissions at critical times are suitably 
unlikely to exceed the CEV and are suitably likely to be well below the 
CEV, the net effect is to provide adequately for attainment. As 
discussed in the NPRM, EPA has conducted analyses to evaluate the 
extent to which longer-term average limits with comparable stringency 
to 1-hour limits at the critical emission value can provide for 
attainment. EPA finds that a comparably stringent limit provides a 
sufficient constraint on the frequency and magnitude of occurrences of 
elevated emissions such that this control strategy will reasonably 
provide for attainment.
    As stated in appendix B of EPA's April 2014 guidance, the Agency 
acknowledges that even with an adjustment to provide comparable 
stringency, a source complying with a longer-term average emission 
limit could possibly have hourly emissions which occasionally exceed 
the critical emission value. In order to assure that SO2 
emission sources will maintain the NAAQS while using longer-term 
average limits, EPA's guidance recommends that 30-day average 
SO2 limits be set at a level below the level that would be 
expected to be protective of the SO2 NAAQS as a 1-hour 
SO2 limit. A facility in compliance with the 30-day limit 
could therefore have occasional spikes of higher concentration, but the 
majority of its hourly impacts must be as low as or lower than those of 
a source which is limited at the critical emission value level. As was 
stated in the NPRM, EPA's statistical analyses of SO2 
emissions data showed that a comparably stringent 30-day average limit 
is likely to result in fewer exceedances and better air quality than 
would occur with 1-hour emissions at the critical emission value.
    Comment: The commenter said that past EPA SO2 policy 
(1994) definitively stated that ``EPA will not approve an 
SO2 SIP with emission limitations based on 30-day average, 
unless the SIP also contains short-term limits established by an 
approved dispersion modeling analysis.'' The commenter also cited past 
actions, including a 1986 memorandum regarding a specific proposed 
facility, in which EPA determined that compliance with a 30-day rolling 
average emission limit under NSPS Subpart Da does not adequately 
demonstrate compliance with short-term NAAQS and PSD increments, 
regardless of sulfur variability.
    EPA Response: In this action, EPA is not changing its position 
regarding the 1-hour emissions limitations to which other facilities, 
as cited by the commenter, are subject. However, the examples that the 
commenter cites predate the release of EPA's April 2014 guidance. They 
reflect EPA's policy for implementing the NAAQS before EPA addressed 
the question of whether it might be possible to devise an effective 
attainment plan using an emission limit with an averaging period longer 
than that of the NAAQS, given appropriate adjustments to make the limit 
comparably stringent to a short-term emission rate that would ensure 
attainment of the SO2 NAAQS. EPA developed the April 2014 
guidance after a lengthy stakeholder outreach process

[[Page 3989]]

regarding implementation strategies for the 2010 SO2 NAAQS. 
As the April 2014 guidance was the first instance in which the Agency 
provided direct guidance for considering adjusted long-term average 
limits for a short-term standard, EPA does not consider the earlier 
documents to countermand the April 2014 guidance on this issue.
    EPA's April 2014 guidance acknowledges that EPA had previously 
recommended that averaging times in SIP emission limits should not 
exceed the averaging time of the applicable NAAQS. However, the April 
2014 guidance expresses EPA's finding that control strategies involving 
limits with averaging times of up to 30 days can provide for attainment 
of the 2010 SO2 NAAQS, where the limits have been set at 
levels expected to be comparably stringent to shorter-term limits. As 
stated in the August 21, 2018 NPRM, EPA considered Ohio's control 
strategy for the Painesville plant and found that the limits in Ohio 
Administrative Code Chapter 3745-18 (OAC 3745-18) met EPA's guidelines 
for acceptable emission limits based on a 30-day averaging time.
    Comment: The commenter stated that a 30-day averaging time is the 
same as a 720-hour averaging period rolling on a daily basis, and ``it 
seems impossible to derive a 720-hour average limit that would ensure 
hourly emissions of SO2 are limited to the extent necessary 
to protect the 1-hour average SO2 NAAQS, unless it was shown 
through air dispersion modeling that the maximum uncontrolled hourly 
emissions from a source would not exceed the NAAQS.''
    EPA Response: The compliance calculations for the limits applicable 
to the Painesville plant units would be 720-hour averages when the unit 
operates in each of those 720 hours. Hours in which the unit is not 
operating are not included in the calculation, to focus the compliance 
test on how well the facility's emissions are controlled during 
operational hours.
    EPA's April 2014 guidance provides the results of analyses which 
demonstrate that limits based on periods of as long as 30 days (720 
hours) can, in many cases, be reasonably considered to provide for 
attainment of the 2010 SO2 NAAQS. When a 30-day emission 
limit is set sufficiently lower than the 1-hour emission limit which 
the modeling analysis indicated would conservatively provide for 
attainment, the numerically lower 30-day limit would also be expected 
to provide for attainment. In accordance with EPA guidance, Ohio 
conducted modeling to determine the CEV, i.e., the emission rate that, 
if emitted continuously, would result in attainment. Ohio then 
established 30-day average limits that are comparably stringent to the 
1-hour limits it otherwise would have established. EPA agrees with Ohio 
that these limits can be expected to provide comparable air quality as 
the corresponding 1-hour limits would, and EPA considers the 30-day 
average limits to satisfy the requirement to provide for attainment.
    EPA does not agree with the commenter that the application of a 
longer term average limit requires determining the unit's maximum 
uncontrolled emission rate or a maximum 1-hour emission rate that might 
occur in compliance with a longer term average emission limit, or that 
modeling must be conducted to show that such emission rates do not 
cause NAAQS violations. The analysis that the commenter proposes would 
not take proper account of the impact of variable emissions within the 
longer-term limit. In particular, while such an analysis would assess 
potential additional exceedances of the NAAQS level on occasions with 
elevated emissions, such an analysis would fail to reflect the improved 
air quality on days with lower emissions. Since compliance with a 
downward adjusted long term average limit necessarily requires any 
occasions of elevated emissions to be accompanied by occasions of lower 
than average emissions, the commenter's proposed analysis is inadequate 
for assessing the net effects of emissions sometimes being higher but 
more often being lower than the CEV.
    Comment: The commenter states that Ohio's approach is inconsistent 
with EPA's Guideline on Air Quality Models, which in Table 8-1 
``requires modeling for short term (<= 24 hours) NAAQS be based on the 
allowable emissions over the averaging time of the NAAQS. Yet, the 
maximum allowable hourly emission rate is difficult to predict from a 
30-day average limit for an emissions unit.''
    EPA Response: EPA's 2014 guidance for SO2 SIPs directly 
addresses the comment regarding Table 8-1. Page A-79 of the guidance 
states:

    An important caveat regarding Table 8-1 of Appendix W is that 
this guidance is oriented toward short term emission limits (e.g., 
1-hour emission limits), as recommended in previous guidance. 
Current guidance, providing for use of longer term emission limits, 
provides that after the state determines the 1-hour limit that would 
be necessary to provide for attainment, any longer-term limit should 
be established at a level that is sufficiently lower to provide 
comparable stringency. Thus, in cases where a state wishes to apply 
a longer term average limit, the attainment analysis would be based 
not on the level of the longer-term limit but rather on the level of 
the corresponding 1-hour emission limit that was shown in the plan 
to be of comparable stringency.

Accordingly, EPA believes that Ohio has provided an appropriate 
demonstration that its 30-day average limit, set to be comparably 
stringent to a 1-hour limit at the modeled CEV, will provide for 
attainment.
    Comment: The commenter said that EPA's April 2014 guidance allows 
flexibility for sources that cannot meet the hourly rate of 
SO2 emissions necessary to attain the NAAQS. The CAA 
requires the implementation of all reasonably available control 
measures to provide for attainment. The commenter said that it is 
reasonable for a source such as the Painesville plant to guard against 
spikes in sulfur content of fuel and/or SO2 emissions 
through proper operation of scrubbers, limiting high sulfur coal, and 
testing for coal sulfur content. The commenter believes that the 
flexibility in EPA's guidance has allowed Ohio to propose 30-day 
average limits for the Painesville plant which fail Congress' direction 
that EPA shall provide for attainment of the NAAQS.
    EPA Response: EPA believes it is important to recognize that some 
sources may have variable emissions, for example due to variations in 
fuel sulfur content and operating rate, that can make it extremely 
difficult, even with a well-designed control strategy, to ensure in 
practice that stringent hourly limits are never exceeded. The 
Painesville plant is complying with the Federal Boiler MACT rule by 
taking enforceable limits on its operations to meet the definition of a 
Limited Use boiler, operating at 10% of its annual heat input capacity. 
As such, the plant will only operate intermittently, during periods of 
high demand or service interruptions. This type of operation reflects a 
decrease in overall emissions from this source.
    The boiler MACT rule does not require that Limited Use boilers 
install additional control technology, because add-on SO2 
control systems require steady-state operations for good control 
efficiency and cannot reduce SO2 emissions effectively for 
intermittent short-term operations. The Painesville plant's revised 
rules do require a reduction in allowable coal sulfur content, with 
coal sampling to confirm sulfur content. Ohio EPA has determined that 
the Painesville plant is unable to use very low sulfur (Powder River 
Basin) coal because of the high cost of updating its facilities to 
handle and use it for its limited operations; because the unique 
characteristics of the coal has a detrimental effect on the

[[Page 3990]]

facility's particulate matter controls; and because of the increased 
risk of fire during storage of the more volatile low-sulfur coal, which 
has occurred elsewhere in Ohio with similar coal storage and handling 
equipment.
    EPA believes that the flexibility of the 30-day average limit is 
reasonable for an intermittently-operating facility such as the 
Painesville plant. As stated previously, EPA's analyses demonstrated 
that its requirement for a tighter limit to be used with a longer-term 
averaging period is likely to yield better air quality than is required 
with a comparably stringent 1-hour limit. EPA's April 2014 guidance 
states, ``if periods of hourly emissions above the critical emission 
value are a rare occurrence at a source, these periods would be 
unlikely to have a significant impact on air quality, insofar as they 
would be very unlikely to occur repeatedly at the times when the 
meteorology is conducive for high ambient concentrations of 
SO2.'' The Painesville plant's limit, supplemented by an 
additional 24-hour boiler heat input cap and the stringent federally 
enforceable limitation on the plant's annual boiler usage, is expected 
to provide for attainment of the NAAQS in accordance with the CAA's 
requirements.

III. What action is EPA taking?

    EPA is approving Ohio's April 3, 2015 plan, as supplemented on 
October 13, 2015 and on March 13, 2017, for attaining the 2010 1-hour 
SO2 NAAQS and for meeting other nonattainment area planning 
requirements for the Lake County SO2 nonattainment area. EPA 
is amending the codification in 40 CFR 52.1870(e) to include the 
approval of Ohio's SO2 attainment plan for Lake County.
    In development of this plan, Ohio amended its rules at OAC 3745-18-
49 (F) (establishing new limits for the Painesville plant), OAC 3745-
18-03 (B)(9), OAC 3745-18-03 (C)(11), and OAC 3745-18-04(D)(10) 
(establishing a compliance date and other administrative provisions), 
and rescinding OAC 3745-18-49(G) (reflecting the enforceable shutdown 
of the Eastlake plant). These revisions became effective on February 
16, 2017. EPA approved these revisions into the SIP, as codified at 40 
CFR 52.1870(c), on October 11, 2018 (83 FR 51361), as part of action on 
a broader range of OAC Chapter 3745-18 revisions. Thus, no additional 
action is necessary to incorporate the pertinent limits into the SIP, 
and this action is limited to concluding that Ohio has demonstrated 
that these previously approved limits provide for attainment of the 
SO2 NAAQS in Lake County and that Ohio has met the other 
planning requirements for this area.

IV. 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, this 
action merely approves state law as meeting Federal requirements and 
does not impose additional requirements beyond those imposed by state 
law. For that reason, this action:
     Is not a significant regulatory action 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);
     Is not an Executive Order 13771 (82 FR 9339, February 2, 
2017) regulatory action because SIP approvals are exempted under 
Executive Order 12866;
     Does not impose an information collection burden under the 
provisions of the Paperwork Reduction Act (44 U.S.C. 3501 et seq.);
     Is certified as not having a significant economic impact 
on a substantial number of small entities under the Regulatory 
Flexibility Act (5 U.S.C. 601 et seq.);
     Does not contain any unfunded mandate or significantly or 
uniquely affect small governments, as described in the Unfunded 
Mandates Reform Act of 1995 (Pub. L. 104-4);
     Does not have Federalism implications as specified in 
Executive Order 13132 (64 FR 43255, August 10, 1999);
     Is not an economically significant regulatory action based 
on health or safety risks subject to Executive Order 13045 (62 FR 
19885, April 23, 1997);
     Is not a significant regulatory action subject to 
Executive Order 13211 (66 FR 28355, May 22, 2001);
     Is 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
     Does 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).
    In addition, the SIP is not approved to apply on any Indian 
reservation land or in any other area where EPA or an Indian tribe has 
demonstrated that a tribe has jurisdiction. In those areas of Indian 
country, the rule does not have tribal implications and will not impose 
substantial direct costs on tribal governments or preempt tribal law as 
specified by Executive Order 13175 (65 FR 67249, November 9, 2000).
    The Congressional Review Act, 5 U.S.C. 801 et seq., as added by the 
Small Business Regulatory Enforcement Fairness Act of 1996, generally 
provides that before a rule may take effect, the agency promulgating 
the rule must submit a rule report, which includes a copy of the rule, 
to each House of the Congress and to the Comptroller General of the 
United States. EPA will submit a report containing this action and 
other required information to the U.S. Senate, the U.S. House of 
Representatives, and the Comptroller General of the United States prior 
to publication of the rule in the Federal Register. A major rule cannot 
take effect until 60 days after it is published in the Federal 
Register. This action is not a ``major rule'' as defined by 5 U.S.C. 
804(2).
    Under section 307(b)(1) of the CAA, petitions for judicial review 
of this action must be filed in the United States Court of Appeals for 
the appropriate circuit by April 15, 2019. Filing a petition for 
reconsideration by the Administrator of this final rule does not affect 
the finality of this action for the purposes of judicial review nor 
does it extend the time within which a petition for judicial review may 
be filed, and shall not postpone the effectiveness of such rule or 
action. This action may not be challenged later in proceedings to 
enforce its requirements. (See section 307(b)(2).)

List of Subjects in 40 CFR Part 52

    Environmental protection, Air pollution control, Incorporation by 
reference, Intergovernmental relations, Reporting and recordkeeping 
requirements, Sulfur oxides.

    Dated: January 29, 2019.
Cathy Stepp,
Regional Administrator, Region 5.

[[Page 3991]]

    40 CFR part 52 is amended as follows:

PART 52--APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS

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

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

0
2. In Sec.  52.1870, the table in paragraph (e) is amended by adding an 
entry for ``SO2 (2010)'' after the entry for 
``PM2.5 (2012)'' under the heading ``Summary of Criteria 
Pollutant Attainment Plans'' to read as follows:

Sec.  52.1870   Identification of plan.

* * * * *
    (e) * * *

                                             EPA-Approved Ohio Nonregulatory and Quasi-Regulatory Provisions
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                  Applicable geographical or non-
              Title                       attainment area           State date                 EPA approval                           Comments
--------------------------------------------------------------------------------------------------------------------------------------------------------
 
                                                                      * * * * * * *
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                     Summary of Criteria Pollutant Attainment Plans
--------------------------------------------------------------------------------------------------------------------------------------------------------
 
                                                                      * * * * * * *
SO2 (2010)......................  Lake County....................    2/16/2017  2/14/2019, [insert Federal Register        EPA is approving the
                                                                                 citation].                                 following plan elements: The
                                                                                                                            emission inventory; the
                                                                                                                            demonstration of attainment;
                                                                                                                            and revised emission limits
                                                                                                                            as meeting RACM
                                                                                                                            requirements.
 
                                                                      * * * * * * *
--------------------------------------------------------------------------------------------------------------------------------------------------------

[FR Doc. 2019-02210 Filed 2-13-19; 8:45 am]
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