83_FR_58429 83 FR 58206 - Approval and Promulgation of Air Quality Implementation Plans; Pennsylvania; Attainment Plan for the Allegheny, Pennsylvania Nonattainment Area for the 2010 Sulfur Dioxide Primary National Ambient Air Quality Standard

83 FR 58206 - Approval and Promulgation of Air Quality Implementation Plans; Pennsylvania; Attainment Plan for the Allegheny, Pennsylvania Nonattainment Area for the 2010 Sulfur Dioxide Primary National Ambient Air Quality Standard

ENVIRONMENTAL PROTECTION AGENCY

Federal Register Volume 83, Issue 223 (November 19, 2018)

Page Range58206-58219
FR Document2018-25079

The Environmental Protection Agency (EPA) is proposing to approve a state implementation plan (SIP) revision, submitted by the Pennsylvania Department of Environmental Protection (PADEP) on behalf of the Allegheny County Health Department (ACHD), to EPA on October 3, 2017, for the purpose of providing for attainment of the 2010 sulfur dioxide (SO<INF>2</INF>) primary national ambient air quality standard (NAAQS) in the Allegheny, Pennsylvania SO<INF>2</INF> nonattainment area (hereafter referred to as the ``Allegheny Area'' or ``Area''). The major sources of SO<INF>2</INF> in the Allegheny Area are the Harsco Metals facility and the facilities which comprise the U.S. Steel (USS) Mon Valley Works: Clairton, Edgar Thomson and Irvin Plants. The Pennsylvania SIP submission is an attainment plan which includes the base year emissions inventory, an analysis of the reasonably available control technology (RACT) and reasonably available control measure (RACM) requirements, enforceable emission limitations and control measures, a reasonable further progress (RFP) plan, a modeling demonstration of SO<INF>2</INF> attainment, a nonattainment New Source Review (NNSR) permit program, and contingency measures for the Allegheny Area. As part of approving the attainment plan, EPA is also proposing to approve new SO<INF>2</INF> emission limits and associated compliance parameters for USS Clairton, Edgar Thomson and Irvin Plants and the Harsco Metals facility into the Allegheny County portion of the Pennsylvania SIP. This action is being taken under the Clean Air Act (CAA).

Federal Register, Volume 83 Issue 223 (Monday, November 19, 2018)
[Federal Register Volume 83, Number 223 (Monday, November 19, 2018)]
[Proposed Rules]
[Pages 58206-58219]
From the Federal Register Online  [www.thefederalregister.org]
[FR Doc No: 2018-25079]


=======================================================================
-----------------------------------------------------------------------

ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 52

[EPA-R03-OAR-2017-0730; FRL-9986-63-Region 3]


Approval and Promulgation of Air Quality Implementation Plans; 
Pennsylvania; Attainment Plan for the Allegheny, Pennsylvania 
Nonattainment Area for the 2010 Sulfur Dioxide Primary National Ambient 
Air Quality Standard

AGENCY: Environmental Protection Agency (EPA).

ACTION: Proposed rule.

-----------------------------------------------------------------------

SUMMARY: The Environmental Protection Agency (EPA) is proposing to 
approve a state implementation plan (SIP) revision, submitted by the 
Pennsylvania Department of Environmental Protection (PADEP) on behalf 
of the Allegheny County Health Department (ACHD), to EPA on October 3, 
2017, for the purpose of providing for attainment of the 2010 sulfur 
dioxide (SO2) primary national ambient air quality standard 
(NAAQS) in the Allegheny, Pennsylvania SO2 nonattainment 
area (hereafter referred to as the ``Allegheny Area'' or ``Area''). The 
major sources of SO2 in the Allegheny Area are the Harsco 
Metals facility and the facilities which comprise the U.S. Steel (USS) 
Mon Valley Works: Clairton, Edgar Thomson and Irvin Plants. The 
Pennsylvania SIP submission is an attainment plan which includes the 
base year emissions inventory, an analysis of the reasonably available 
control technology (RACT) and reasonably available control measure 
(RACM)

[[Page 58207]]

requirements, enforceable emission limitations and control measures, a 
reasonable further progress (RFP) plan, a modeling demonstration of 
SO2 attainment, a nonattainment New Source Review (NNSR) 
permit program, and contingency measures for the Allegheny Area. As 
part of approving the attainment plan, EPA is also proposing to approve 
new SO2 emission limits and associated compliance parameters 
for USS Clairton, Edgar Thomson and Irvin Plants and the Harsco Metals 
facility into the Allegheny County portion of the Pennsylvania SIP. 
This action is being taken under the Clean Air Act (CAA).

DATES: Written comments must be received on or before December 19, 
2018.

ADDRESSES: Submit your comments, identified by Docket ID No. EPA-R03-
OAR-2017-0730 at http://www.regulations.gov, or via email to 
spielberger.susan@epa.gov. For comments submitted at Regulations.gov, 
follow the online instructions for submitting comments. Once submitted, 
comments cannot be edited or removed from Regulations.gov. For either 
manner of submission, 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, please contact the person 
identified in the FOR FURTHER INFORMATION CONTACT section. For the full 
EPA public comment policy, information about CBI or multimedia 
submissions, and general guidance on making effective comments, please 
visit http://www2.epa.gov/dockets/commenting-epa-dockets.

FOR FURTHER INFORMATION CONTACT: Leslie Jones Doherty, (215) 814-3409, 
or by email at jones.leslie@epa.gov.

SUPPLEMENTARY INFORMATION: 

Table of Contents

I. Background for EPA's Proposed Action
II. Requirements for SO2 Nonattainment Plans
III. Attainment Demonstration and Longer Term Averaging
IV. Pennsylvania's Attainment Plan Submittal for the Allegheny Area
V. EPA's Analysis of Pennsylvania's Attainment Plan Submittal for 
the Allegheny Area
    A. Pollutants Addressed
    B. Emissions Inventory Requirements
    C. Air Quality Modeling
    D. RACM/RACT
    E. RFP Plan
    F. Contingency Measures
    G. New Source Review
VI. EPA's Proposed Action
VII. Incorporation by Reference
VIII. Statutory and Executive Order Reviews

I. Background for EPA's Proposed Action

    On June 2, 2010, the EPA Administrator signed a final rule 
establishing a new SO2 primary NAAQS as a 1-hour standard of 
75 parts per billion (ppb), based on a 3-year average of the annual 
99th percentile of daily maximum 1-hour average concentrations. See 75 
FR 35520 (June 22, 2010), 40 CFR 50.17. This action also revoked the 
existing 1971 annual standard and 24-hour standards, subject to certain 
conditions.\1\ EPA established the NAAQS based on significant evidence 
and numerous health studies demonstrating that serious health effects 
are associated with short-term exposures to SO2 emissions 
ranging from 5 minutes to 24 hours with an array of adverse respiratory 
effects including narrowing of the airways which can cause difficulty 
breathing (bronchoconstriction) and increased asthma symptoms. For more 
information regarding the health impacts of SO2, please 
refer to the June 22, 2010, final rulemaking. See 75 FR 35520. 
Following promulgation of a new or revised NAAQS, EPA is required by 
the CAA to designate areas throughout the United States as attaining or 
not attaining the NAAQS; this designation process is described in 
section 107(d)(1) of the CAA. On August 5, 2013, EPA promulgated 
initial air quality designations for 29 areas for the 2010 
SO2 NAAQS (78 FR 47191), which became effective on October 
4, 2013, based on violating air quality monitoring data for calendar 
years 2009-2011, where there was sufficient data to support a 
nonattainment designation.\2\
---------------------------------------------------------------------------

    \1\ With certain exceptions, EPA's June 22, 2010 final action 
revoked the two 1971 primary 24-hour standard of 140 ppb and the 
annual standard of 30 ppb because they were determined not to add 
additional public health protection given a 1-hour standard at 75 
ppb. See 75 FR 35520. However, the secondary 3-hour SO2 
standard was retained. Because Allegheny County has already been 
designated for the 2010 1-hour SO2 NAAQS and was neither 
designated nonattainment nor subject to a SIP call for the 1971 
primary standards, these standards have been revoked for this area. 
See 40 CFR 50.4(e).
    \2\ EPA is continuing its designation efforts for the 2010 
SO2 NAAQS. Pursuant to a court-order issued on March 2, 
2015, by the U.S. District Court for the Northern District of 
California, EPA must complete the remaining designations for the 
rest of the country on a schedule that contains three specific 
deadlines. Sierra Club, et al. v. Environmental Protection Agency, 
13-cv-03953-SI (2015).
---------------------------------------------------------------------------

    Effective on October 4, 2013, the Allegheny Area was designated as 
nonattainment for the 2010 SO2 NAAQS for an area that 
encompasses the primary SO2 emitting sources of the Harsco 
Metals facility and the USS Mon Valley Works (Clairton, Edgar Thomson 
and Irvin Plants). The Allegheny Area is comprised of a portion of 
Allegheny County which includes the City of Clairton, City of Duquesne, 
City of McKeesport, Borough of Braddock, Borough of Dravosburg, Borough 
of East McKeesport, Borough of East Pittsburgh, Borough of Elizabeth, 
Borough of Glassport, Borough of Jefferson Hills, Borough of Liberty, 
Borough of Lincoln, Borough of North Braddock, Borough of Pleasant 
Hills, Borough of Port Vue, Borough of Versailles, Borough of Wall, 
Borough of West Elizabeth, Borough of West Mifflin, Elizabeth Township, 
Forward Township, and North Versailles Township in Pennsylvania. The 
October 4, 2013 final designation triggered a requirement for 
Pennsylvania to submit a SIP revision with an attainment plan for how 
the Area would attain the 2010 SO2 NAAQS as expeditiously as 
practicable, but no later than October 4, 2018, in accordance with CAA 
sections 172 and 191-192.
    For a number of areas, including the Allegheny Area, EPA published 
a notice on March 18, 2016, that Pennsylvania and other pertinent 
states had failed to submit the required SO2 attainment plan 
by this submittal deadline. See 81 FR 14736. This finding initiated a 
deadline under CAA section 179(a) for the potential imposition of new 
source review and highway funding sanctions. However, pursuant to 
Pennsylvania's submittal of October 3, 2017, and EPA's subsequent 
letter dated October 6, 2017 to Pennsylvania finding the submittal 
complete and noting the stopping of the sanctions' deadline, these 
sanctions under section 179(a) will not be imposed as a consequence of 
Pennsylvania's having missed the original deadline. Additionally, under 
CAA section 110(c), the finding triggers a requirement that EPA 
promulgate a federal implementation plan (FIP) within two years of the 
effective date of the finding unless, by that time, the state has made 
the necessary complete

[[Page 58208]]

submittal and EPA has approved the submittal as meeting applicable 
requirements.

II. Requirements for SO2 Nonattainment Area Plans

    Attainment plans must meet the applicable requirements of the CAA, 
and specifically CAA sections 172, 191, and 192. The required 
components of an attainment plan submittal are listed in section 172(c) 
of Title 1, part D of the CAA. The EPA's regulations governing 
nonattainment SIPs are set forth at 40 CFR part 51, with specific 
procedural requirements and control strategy requirements residing at 
subparts F and G, respectively. Soon after Congress enacted the 1990 
Amendments to the CAA, EPA issued comprehensive guidance on SIPs, in a 
document entitled the ``General Preamble for the Implementation of 
Title I of the Clean Air Act Amendments of 1990,'' published at 57 FR 
13498 (April 16, 1992) (General Preamble). Among other things, the 
General Preamble addressed SO2 SIPs and fundamental 
principles for SIP control strategies. Id. at 13545-49, 13567-68. On 
April 23, 2014, EPA issued recommended guidance (hereafter 2014 
SO2 Nonattainment Guidance) for how state submissions could 
address the statutory requirements for SO2 attainment 
plans.\3\ In this guidance, EPA described the statutory requirements 
for an attainment plan, which includes: An accurate base year emissions 
inventory of current emissions for all sources of SO2 within 
the nonattainment area (172(c)(3)); an attainment demonstration that 
includes a modeling analysis showing that the enforceable emissions 
limitations and other control measures taken by the state will provide 
for expeditious attainment of the NAAQS (172(c)); RFP (172(c)(2)); 
implementation of RACM, including RACT (172(c)(1)); NNSR requirements 
(172(c)(5)); and adequate contingency measures for the affected area 
(172(c)(9)). A synopsis of these requirements is also provided in the 
notice of proposed rulemaking on the Illinois SO2 
nonattainment plans, published on October 5, 2017 at 82 FR 46434.
---------------------------------------------------------------------------

    \3\ See ``Guidance for 1-Hour SO2 Nonattainment Area 
SIP Submissions'' (April 23, 2014), available at https://www.epa.gov/sites/production/files/2016-06/documents/20140423guidance_nonattainment_sip.pdf.
---------------------------------------------------------------------------

    In order for EPA to fully approve a SIP as meeting the requirements 
of CAA sections 110, 172 and 191-192 and EPA's regulations at 40 CFR 
part 51, the SIP for the affected area needs to demonstrate to EPA's 
satisfaction that each of the aforementioned requirements have been 
met. Under CAA sections 110(l) and 193, EPA may not approve a SIP that 
would interfere with any applicable requirement concerning NAAQS 
attainment and RFP, or any other applicable requirement, and no 
requirement in effect (or required to be adopted by an order, 
settlement, agreement, or plan in effect before November 15, 1990) in 
any area which is a nonattainment area for any air pollutant, may be 
modified in any manner unless it insures equivalent or greater emission 
reductions of such air pollutant.

III. Attainment Demonstration and Longer Term Averaging

    CAA section 172(c)(1) directs states with areas designated as 
nonattainment to demonstrate that the submitted plan provides for 
attainment of the NAAQS. 40 CFR part 51, subpart G further delineates 
the control strategy requirements that SIPs must meet, and EPA has long 
required that all SIPs and control strategies reflect four fundamental 
principles of quantification, enforceability, replicability, and 
accountability. General Preamble, at 13567-68. SO2 
attainment plans must consist of two components: (1) Emission limits 
and other control measures that assure implementation of permanent, 
enforceable and necessary emission controls, and (2) a modeling 
analysis which meets the requirements of 40 CFR part 51, Appendix W 
which demonstrates that these emission limits and control measures 
provide for timely attainment of the primary SO2 NAAQS as 
expeditiously as practicable, but by no later than the attainment date 
for the affected area. In all cases, the emission limits and control 
measures must be accompanied by appropriate methods and conditions to 
determine compliance with the respective emission limits and control 
measures and must be quantifiable (i.e., a specific amount of emission 
reduction can be ascribed to the measures), fully enforceable 
(specifying clear, unambiguous and measurable requirements for which 
compliance can be practicably determined), replicable (the procedures 
for determining compliance are sufficiently specific and non-subjective 
so that two independent entities applying the procedures would obtain 
the same result), and accountable (source specific limits must be 
permanent and must reflect the assumptions used in the SIP 
demonstrations). EPA's 2014 SO2 Nonattainment Guidance 
recommends that the emission limits established for the attainment 
demonstration be expressed as short-term average limits (e.g., 
addressing emissions averaged over one or three hours), but also 
describes the option to utilize emission limits with longer averaging 
times of up to 30 days so long as the state meets various suggested 
criteria. See 2014 SO2 Nonattainment Guidance, pp. 22 to 39. 
The guidance recommends that--should states and sources utilize longer 
averaging times--the longer term average limit should be set at an 
adjusted level that reflects a stringency comparable to the 1-hour 
average limit at the critical emission value shown to provide for 
attainment that the plan otherwise would have set.
    The 2014 SO2 Nonattainment Guidance provides an 
extensive discussion of EPA's rationale for positing that appropriately 
set comparably stringent limitations based on averaging times as long 
as 30 days can be found to provide for attainment of the 2010 
SO2 NAAQS. In evaluating this option, EPA considered the 
nature of the standard, conducted detailed analyses of the impact of 
use of 30-day average limits on the prospects for attaining the 
standard, and carefully reviewed how best to achieve an appropriate 
balance among the various factors that warrant consideration in judging 
whether a state's plan provides for attainment. Id. at pp. 22 to 39. 
See also id. at Appendices B, C, and D.
    As specified in 40 CFR 50.17(b), the 1-hour primary SO2 
NAAQS is met at an ambient air quality monitoring site when the 3-year 
average of the annual 99th percentile of daily maximum 1-hour average 
concentrations is less than or equal to 75 ppb. In a year with 365 days 
of valid monitoring data, the 99th percentile would be the fourth 
highest daily maximum 1-hour value. The 2010 SO2 NAAQS, 
including this form of determining compliance with the standard, was 
upheld by the U.S. Court of Appeals for the District of Columbia 
Circuit in Nat'l Envt'l Dev. Ass'n's Clean Air Project v. EPA, 686 F.3d 
803 (D.C. Cir. 2012). Because the standard has this form, a single 
exceedance does not create a violation of the standard. Instead, at 
issue is whether a source operating in compliance with a properly set 
longer term average could cause exceedances, and if so the resulting 
frequency and magnitude of such exceedances, and in particular whether 
EPA can have reasonable confidence that a properly set longer term 
average limit will provide that the average fourth highest daily 
maximum value will be at or below 75 ppb. A synopsis of how EPA judges 
whether such plans ``provide for attainment,'' based on modeling of 
projected allowable

[[Page 58209]]

emissions and in light of the NAAQS' form for determining attainment at 
monitoring sites follows.
    For SO2 plans based on 1-hour emission limits, the 
standard approach is to conduct modeling using fixed emission rates. 
The maximum emission rate that would be modeled to result in attainment 
(i.e., in an ``average year'' \4\ shows three, not four days with 
maximum hourly levels exceeding 75 ppb) is labeled the ``critical 
emission value.'' The modeling process for identifying this critical 
emissions value inherently considers the numerous variables that affect 
ambient concentrations of SO2, such as meteorological data, 
background concentrations, and topography. In the standard approach, 
the state would then provide for attainment by setting a continuously 
applicable 1-hour emission limit at this critical emission value.
---------------------------------------------------------------------------

    \4\ An ``average year'' is used to mean a year with average air 
quality. While 40 CFR 50 Appendix T provides for averaging three 
years of 99th percentile daily maximum values (e.g., the fourth 
highest maximum daily concentration in a year with 365 days with 
valid data), this discussion and an example below uses a single 
``average year'' in order to simplify the illustration of relevant 
principles.
---------------------------------------------------------------------------

    EPA recognizes that some sources have highly 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 emissions for any given 
hour do not exceed the critical emission value. EPA also acknowledges 
the concern that longer term emission limits can allow short periods 
with emissions above the ``critical emissions value,'' which, if 
coincident with meteorological conditions conducive to high 
SO2 concentrations, could in turn create the possibility of 
a NAAQS exceedance occurring on a day when an exceedance would not have 
occurred if emissions were continuously controlled at the level 
corresponding to the critical emission value. However, for several 
reasons, EPA believes that the approach recommended in its guidance 
document suitably addresses this concern. First, from a practical 
perspective, EPA expects the actual emission profile of a source 
subject to an appropriately set longer term average limit to be similar 
to the emission profile of a source subject to an analogous 1-hour 
average limit. EPA expects this similarity because it has recommended 
that the longer term average limit be set at a level that is comparably 
stringent to the otherwise applicable 1-hour limit (reflecting a 
downward adjustment from the critical emissions value) and that takes 
the source's emissions profile into account. As a result, EPA expects 
either form of emission limit to yield comparable air quality.
    Second, from a more theoretical perspective, EPA has compared the 
likely air quality with a source having maximum allowable emissions 
under an appropriately set longer term limit, as compared to the likely 
air quality with the source having maximum allowable emissions under 
the comparable 1-hour limit. In this comparison, in the 1-hour average 
limit scenario, the source is presumed at all times to emit at the 
critical emission level, and in the longer term average limit scenario, 
the source is presumed occasionally to emit more than the critical 
emission value but on average, and presumably at most times, to emit 
well below the critical emission value. In an ``average year,'' 
compliance with the 1-hour limit is expected to result in three 
exceedance days (i.e., three days with hourly values above 75 ppb) and 
a fourth day with a maximum hourly value at 75 ppb. By comparison, with 
the source complying with a longer term limit, it is possible that 
additional exceedances would occur that would not occur in the 1-hour 
limit scenario (if emissions exceed the critical emission value at 
times when meteorology is conducive to poor air quality). However, this 
comparison must also factor in the likelihood that exceedances that 
would be expected in the 1-hour limit scenario would not occur in the 
longer term limit scenario. This result arises because the longer term 
limit requires lower emissions most of the time (because the limit is 
set well below the critical emission value), so a source complying with 
an appropriately set longer term limit is likely to have lower 
emissions at critical times than would be the case if the source were 
emitting as allowed with a 1-hour limit.
    As a hypothetical example to illustrate these points, suppose a 
source that always emits 1000 pounds of SO2 per hour, which 
results in air quality at the level of the NAAQS (i.e., results in a 
design value of 75 ppb). Suppose further that in an ``average year,'' 
these emissions cause the 5 highest maximum daily average 1-hour 
concentrations to be 100 ppb, 90 ppb, 80 ppb, 75 ppb, and 70 ppb. Then 
suppose that the source becomes subject to a 30-day average emission 
limit of 700 pounds per hour. It is theoretically possible for a source 
meeting this limit to have emissions that occasionally exceed 1000 
pounds per hour, but with a typical emissions profile, emissions would 
much more commonly be between 600 and 800 pounds per hour. In this 
simplified example, assume a zero background concentration, which 
allows one to assume a linear relationship between emissions and air 
quality. (A nonzero background concentration would make the mathematics 
more difficult but would give similar results.) Air quality will depend 
on what emissions happen on what critical hours, but suppose that 
emissions at the relevant times on these 5 days are 800 pounds/hour 
(lb/hr), 1100 pounds per hour, 500 pounds per hour, 900 pounds per 
hour, and 1200 pounds per hour, respectively. (This is a conservative 
example because the average of these emissions, 900 pounds per hour, is 
well over the 30-day average emission limit.) These emissions would 
result in daily maximum 1-hour concentrations of 80 ppb, 99 ppb, 40 
ppb, 67.5 ppb, and 84 ppb. In this example, the fifth day would have an 
exceedance that would not otherwise have occurred, but the third day 
would not have an exceedance that otherwise would have occurred, and 
the fourth day would have been below, rather than at, 75 ppb. In this 
example, the fourth highest maximum daily concentration under the 30-
day average would be 67.5 ppb.
    This simplified example illustrates the findings of a more 
complicated statistical analysis that EPA conducted using a range of 
scenarios using actual plant data. As described in Appendix B of EPA's 
2014 SO2 Nonattainment Guidance, EPA found that the 
requirement for lower average emissions is highly likely to yield 
better air quality than is required with a comparably stringent 1-hour 
limit. Based on analyses described in Appendix B of its 2014 
SO2 Nonattainment Guidance, EPA expects that an emission 
profile with maximum allowable emissions under an appropriately set 
comparably stringent 30-day average limit is likely to have the net 
effect of having a lower number of exceedances and better air quality 
than an emission profile with maximum allowable emissions under a 1-
hour emission limit at the critical emission value. This result 
provides a compelling policy rationale for allowing the use of a longer 
averaging period, in appropriate circumstances where the facts indicate 
this result can be expected to occur.
    The question then becomes whether this approach, which is likely to 
produce a lower number of overall exceedances even though it may 
produce some unexpected exceedances above the critical emission value, 
meets the requirement in section 110(a)(1) and 172(c)(1) for SIPs to 
``provide for attainment'' of the NAAQS. For SO2, as for 
other pollutants, it is generally impossible to design a nonattainment

[[Page 58210]]

plan in the present that will guarantee that attainment will occur in 
the future. A variety of factors can cause a well-designed attainment 
plan to fail and unexpectedly not result in attainment, for example if 
meteorology occurs that is more conducive to poor air quality than was 
anticipated in the plan. Therefore, in determining whether a plan meets 
the requirement to provide for attainment, EPA's task is commonly to 
judge not whether the plan provides absolute certainty that attainment 
will in fact occur, but rather whether the plan provides an adequate 
level of confidence of prospective NAAQS attainment. From this 
perspective, in evaluating use of a 30-day average limit, EPA must 
weigh the likely net effect on air quality. Such an evaluation must 
consider the risk that occasions with meteorology conducive to high 
concentrations will have elevated emissions leading to exceedances that 
would not otherwise have occurred, and must also weigh the likelihood 
that the requirement for lower emissions on average will result in days 
not having exceedances that would have been expected with emissions at 
the critical emissions value. Additional policy considerations, such as 
in this case the desirability of accommodating real world emissions 
variability without significant risk of violations, are also 
appropriate factors for the EPA to weigh in judging whether a plan 
provides a reasonable degree of confidence that the plan will lead to 
attainment. Based on these considerations, especially given the high 
likelihood that a continuously enforceable limit averaged over as long 
as 30 days, determined in accordance with EPA's guidance, will result 
in attainment, EPA believes as a general matter that such limits, if 
appropriately determined, can reasonably be considered to provide for 
attainment of the 2010 SO2 NAAQS.
    The 2014 SO2 Nonattainment Guidance offers specific 
recommendations for determining an appropriate longer term average 
limit. The recommended method starts with determination of the 1-hour 
emission limit that would provide for attainment (i.e., the critical 
emission value), and applies an adjustment factor to determine the 
(lower) level of the longer term average emission limit that would be 
estimated to have a stringency comparable to the otherwise necessary 1-
hour emission limit. This method uses a database of continuous emission 
data reflecting the type of control that the source will be using to 
comply with the SIP emission limits, which (if compliance requires new 
controls) may require use of an emission database from another source. 
The recommended method involves using these data to compute a complete 
set of emission averages, computed according to the averaging time and 
averaging procedures of the prospective emission limitation. In this 
recommended method, the ratio of the 99th percentile among these long 
term averages to the 99th percentile of the 1-hour values represents an 
adjustment factor that may be multiplied by the candidate 1-hour 
emission limit to determine a longer term average emission limit that 
may be considered comparably stringent.\5\ The 2014 SO2 
Nonattainment Guidance also addresses a variety of related topics, such 
as the potential utility of setting supplemental emission limits, such 
as mass-based limits, to reduce the likelihood and/or magnitude of 
elevated emission levels that might occur under the longer term 
emission rate limit.
---------------------------------------------------------------------------

    \5\ For example, if the critical emission value is 1000 pounds 
of SO2 per hour, and a suitable adjustment factor is 
determined to be 70 percent, the recommended longer term average 
limit would be 700 pounds per hour.
---------------------------------------------------------------------------

    Preferred air quality models for use in regulatory applications are 
described in Appendix A of EPA's Guideline on Air Quality Models (40 
CFR part 51, Appendix W).\6\ In 2005, EPA promulgated the American 
Meteorological Society/Environmental Protection Regulatory Model 
(AERMOD) as the Agency's preferred near-field dispersion modeling for a 
wide range of regulatory applications addressing stationary sources 
(for example in estimating SO2 concentrations) in all types 
of terrain based on extensive developmental and performance evaluation. 
Supplemental guidance on modeling for purposes of demonstrating 
attainment of the SO2 standard is provided in Appendix A to 
the April 23, 2014 SO2 nonattainment area SIP guidance 
document referenced above. Appendix A provides extensive guidance on 
the modeling domain, the source inputs, assorted types of 
meteorological data, and background concentrations. Consistency with 
the recommendations in this guidance is generally necessary for the 
attainment demonstration to offer adequately reliable assurance that 
the plan provides for attainment.
---------------------------------------------------------------------------

    \6\ The EPA published revisions to the Guideline on Air Quality 
Models on January 17, 2017.
---------------------------------------------------------------------------

    As stated previously, attainment demonstrations for the 2010 1-hour 
primary SO2 NAAQS must demonstrate future attainment and 
maintenance of the NAAQS in the entire area designated as nonattainment 
(i.e., not just at the violating monitor) by using air quality 
dispersion modeling (See Appendix W to 40 CFR part 51) to show that the 
mix of sources and enforceable control measures and emission rates in 
an identified area will not lead to a violation of the SO2 
NAAQS. For a short-term (i.e., 1-hour) standard, EPA believes that 
dispersion modeling, using allowable emissions and addressing 
stationary sources in the affected area (and in some cases those 
sources located outside the nonattainment area which may affect 
attainment in the area) is technically appropriate, efficient and 
effective in demonstrating attainment in nonattainment areas because it 
takes into consideration combinations of meteorological and emission 
source operating conditions that may contribute to peak ground-level 
concentrations of SO2.
    The meteorological data used in the analysis should generally be 
processed with the most recent version of AERMOD Meteorological 
Preprocessor (AERMET). Estimated concentrations should include ambient 
background concentrations, should follow the form of the standard, and 
should be calculated as described in section 2.6.1.2 of the August 23, 
2010 clarification memo on ``Applicability of Appendix W Modeling 
Guidance for the 1-hr SO2 National Ambient Air Quality 
Standard'' (U. S. EPA, 2010a).

IV. Pennsylvania's Attainment Plan Submittal for the Allegheny Area

    In accordance with section 172(c) of the CAA, the Pennsylvania 
attainment plan for the Allegheny County Area includes: (1) An 
emissions inventory for SO2 for the plan's base year (2011); 
(2) an attainment demonstration including analyses that locate, 
identify, and quantify sources of emissions contributing to violations 
of the 2010 SO2 NAAQS as well as a dispersion modeling 
analysis of an emissions control strategy for the primary 
SO2 sources (USS Clairton, Edgar Thomson and Irvin Plants 
and Harsco Metals) showing attainment of the SO2 NAAQS by 
the October 4, 2018 attainment date; (3) a determination that the 
control strategy for the primary SO2 source within the 
nonattainment areas constitutes RACM/RACT; (4) requirements for RFP 
toward attaining the SO2 NAAQS in the Area; (5) contingency 
measures; (6) the assertion that Pennsylvania's existing SIP-approved 
NNSR program meets the applicable requirements for SO2; and 
(7) the request that emission limitations and compliance parameters for 
Clairton, Edgar Thomson and Irvin Plants and Harsco Metals be 
incorporated into the SIP.

[[Page 58211]]

V. EPA's Analysis of Pennsylvania's Attainment Plan Submittal for the 
Allegheny Area

    Consistent with CAA requirements (see section 172), an attainment 
demonstration for a SO2 nonattainment area must include a 
showing that the area will attain the 2010 SO2 NAAQS as 
expeditiously as practicable. The demonstration must also meet the 
requirements of 40 CFR 51.112 and 40 CFR part 51, Appendix W, and 
include inventory data, modeling results, and emissions reductions 
analyses on which the state has based its projected attainment. EPA is 
proposing that the attainment plan submitted by Pennsylvania is 
sufficient, and EPA is proposing to approve the plan to ensure ongoing 
attainment.

A. Pollutants Addressed

    Pennsylvania's SO2 attainment plan evaluates 
SO2 emissions for the Allegheny Area comprised of a portion 
of Allegheny County that is designated nonattainment for the 2010 
SO2 NAAQS. There are no precursors to consider for the 
SO2 attainment plan. SO2 is a pollutant that 
arises from direct emissions, and therefore concentrations are highest 
relatively close to the sources and much lower at greater distances due 
to dispersion. Thus, SO2 concentration patterns resemble 
those of other directly emitted pollutants like lead, and differ from 
those of photochemically-formed (secondary) pollutants such as ozone. 
Pennsylvania's attainment plan appropriately considered SO2 
emissions for the Allegheny Area.

B. Emissions Inventory Requirements

    States are required under section 172(c)(3) of the CAA to develop 
comprehensive, accurate and current emissions inventories of all 
sources of the relevant pollutant or pollutants in the nonattainment 
area. These inventories provide detailed accounting of all emissions 
and emissions sources by precursor or pollutant. In addition, 
inventories are used in air quality modeling to demonstrate that 
attainment of the NAAQS is as expeditious as practicable. The 2014 
SO2 Nonattainment Guidance provides that the emissions 
inventory should be consistent with the Air Emissions Reporting 
Requirements (AERR) at Subpart A to 40 CFR part 51.\7\
---------------------------------------------------------------------------

    \7\ The AERR at Subpart A to 40 CFR part 51 cover overarching 
Federal reporting requirements for the states to submit emissions 
inventories for criteria pollutants to EPA's Emissions Inventory 
System. EPA uses these submittals, along with other data sources, to 
build the National Emissions Inventory.
---------------------------------------------------------------------------

    For the base year inventory of actual emissions, a ``comprehensive, 
accurate and current'' inventory can be represented by a year that 
contributed to the three-year design value used for the original 
nonattainment designation. The 2014 SO2 Nonattainment 
Guidance notes that the base year inventory should include all sources 
of SO2 in the nonattainment area as well as any sources 
located outside the nonattainment area which may affect attainment in 
the area. Pennsylvania appropriately elected to use 2011 as the base 
year. Actual emissions from all the sources of SO2 in the 
Allegheny Area were reviewed and compiled for the base year emissions 
inventory requirement. The primary SO2-emitting point 
sources located within the Allegheny Area are the USS Mon Valley 
Works--Clairton, Edgar Thomson and Irvin Plants with SO2 
emissions in 2011 of 1468 tons per year (tpy), 1279 tpy, and 419 tpy, 
respectively. The Harsco Metals facility which is located on the Edgar 
Thomson plant property is the next largest source with 7 tpy of 
SO2 emissions in 2011. A more detailed discussion of the 
emissions inventory for the Allegheny Area and EPA's analysis of the 
Area can be found in Pennsylvania's October 3, 2017 submittal as well 
as the emissions inventory Technical Support Document (TSD), which can 
be found under Docket ID No. EPA-R03-OAR-2017-0730 and which is 
available online at www.regulations.gov.
    Table 1 shows the level of emissions, expressed in tpy, in the 
Allegheny Area for the 2011 base year by emissions source category.

 Table 1--2011 Base Year SO2 Emissions Inventory for the Allegheny Area
------------------------------------------------------------------------
                                                         SO2 emissions
               Emission source category                      (tpy)
------------------------------------------------------------------------
Point................................................            3249.20
Area.................................................             158.85
Non-road.............................................               1.17
On-road..............................................               8.11
                                                      ------------------
  Total..............................................            3417.33
------------------------------------------------------------------------

    EPA has evaluated Pennsylvania's 2011 base year emissions inventory 
for the Allegheny Area and has made the determination that this 
inventory was developed consistent with EPA's guidance. Therefore, 
pursuant to section 172(c)(3), EPA is proposing to approve 
Pennsylvania's 2011 base year emissions inventory for the Allegheny 
Area.
    The attainment demonstration also provides for a projected 
attainment year inventory that includes estimated emissions for all 
emission sources of SO2 which are determined to impact the 
nonattainment area for the year in which the Area is expected to attain 
the NAAQS. Pennsylvania provided a 2018 projected emissions inventory 
for all known sources included in the 2011 base year inventory, and EPA 
finds Pennsylvania appropriately developed this inventory as discussed 
in the emissions inventory TSD. The projected 2018 emissions are shown 
in Table 2. Pennsylvania's submittal asserts that the SO2 
emissions are expected to decrease by approximately 618 tons, or 18%, 
by 2018 from the 2011 base year.\8\ A detailed discussion of the 
projected emissions for the Allegheny Area and EPA's analysis of 
emissions can be found in Pennsylvania's October 3, 2017 submittal as 
well as in the emissions inventory TSD, which can be found under Docket 
ID No. EPA-R03-OAR-2017-0730 and online at www.regulations.gov.
---------------------------------------------------------------------------

    \8\ Reductions in projected 2018 SO2 emissions in the 
onroad, nonroad and nonpoint source categories can be attributed to 
lower sulfur content limits for gasoline and diesel fuels for the 
onroad and nonroad sector, and more stringent sulfur content limits 
on home heating oil and other distillate/residual fuel oils for the 
nonpoint sector which limits are included in the Pennsylvania SIP. 
Reductions in projected 2018 SO2 emissions for point 
sources are a result of the limits discussed in the RACT/RACM 
section of this rulemaking.

  Table 2--2018 Projected SO2 Emission Inventory for the Allegheny Area
------------------------------------------------------------------------
                                                         SO2 emissions
               Emission source category                      (tpy)
------------------------------------------------------------------------
Point................................................            2676.52
Area.................................................             119.18
Non-road.............................................               0.44
On-road..............................................               2.96
                                                      ------------------
  Total..............................................            2799.10
------------------------------------------------------------------------

C. Air Quality Modeling

    The SO2 attainment demonstration provides an air quality 
dispersion modeling analysis to demonstrate that control strategies 
chosen to reduce SO2 source emissions will bring the Area 
into attainment by the statutory attainment date of October 4, 2018. 
The modeling analysis, which the state is to conduct in accordance with 
Appendix W to 40 CFR part 51 (EPA's Modeling Guidance), is used for the 
attainment demonstration to assess the control strategy for a 
nonattainment area and establish emission limits that will provide for 
attainment. In accordance with Appendix W, three years of prognostic 
meteorological data was used

[[Page 58212]]

to simulate the dispersion of pollutant plumes from multiple point, 
area, or volume sources across the averaging times of interest. The 
modeling demonstration typically also relies on maximum allowable 
emissions from sources in the nonattainment area. Though the actual 
emissions are likely to be below the allowable emissions, sources have 
the ability to run at higher production rates or optimize controls such 
that emissions approach the allowable emissions limits. An attainment 
plan must provide for attainment under all allowable scenarios of 
operation for each source based on the maximum allowable emissions.
    ACHD provided an analysis which was developed in accordance with 
EPA's Modeling Guidance and the 2014 SO2 Nonattainment 
Guidance, and was prepared using the EPA dispersion modeling system, 
AERMOD. This modeling demonstration also utilized the Weather Research 
and Forecasting (WRF) model to generate prognostic meteorological data. 
EPA's Mesoscale Model Interface Program (MMIF) was used to extract the 
prognostic meteorological data which was processed using AERMET, a pre-
processor to AERMOD, in accordance with 40 CFR part 51. EPA notes that 
our most recent version of 40 CFR part 51 Appendix W allows for 
prognostic meteorological data to be used in AERMOD. The prognostic 
meteorological data was extracted and processed following the 
methodology outlined in EPA's updated Appendix W and other applicable 
guidance. In the particular circumstances in this Area, in which local 
topographical influences are likely to be channeling flows in a manner 
prone to yield different flows for different facilities in the Area, 
EPA believes that the prognostic meteorological data generated by ACHD 
are likely to provide a better characterization of winds in this Area 
than application of a single hourly wind speed and direction across the 
Area. EPA also conducted its own land use survey (using the methods of 
Auer), finding that about 70 percent (%) of the Area within an area out 
to three kilometers from the main sources in the Area may be considered 
rural land use, which supports ACHD's use of rural dispersion 
coefficients in its modeling analysis. Further discussion of ACHD's 
development of these meteorological data and EPA's land use survey can 
be found in EPA's modeling TSD, which can be found under Docket ID No. 
EPA-R03-OAR-2017-0730.
    ACHD characterized USS's Clairton Coke Works fugitive coke oven 
emissions using an alternative modeling technique, which shows 
significantly better model performance over the regulatory version of 
AERMOD. Given the high temperatures of these fugitive emissions, ACHD 
recognized that the plume rise and initial plume characteristics vary 
by hour reflecting hourly variations in meteorology in a manner that is 
not addressed in simple treatments of volume sources in AERMOD. 
Therefore, ACHD used an alternate method, using EPA's Buoyant Line and 
Point Source Model (BLP), to determine hourly values of these 
parameters. Since AERMOD does not provide for volume sources to have 
heat flux or otherwise to have plume rise, ACHD used hourly release 
heights reflecting the plume height for each hour's meteorology 
estimated by the BLP Plume Rise module. Similarly, ACHD used hourly 
values which characterize the initial width and height of the release 
based on hourly plume dimensions determined by BLP. Fugitive emissions 
were then included in AERMOD for each of the multiple volume sources 
used to represent the coke batteries in the Area by using volume 
sources with hourly release heights and initial dispersion coefficients 
determined in this manner, as contained in an hourly emission rate 
file. This alternative method is referred to as the BLP/AERMOD Hybrid 
approach.
    As noted in ACHD's modeling protocol document (See Appendix A of 
Pennsylvania's October 3, 2017 submittal), the procedure for handling 
USS's coke oven fugitive emissions in the dispersion modeling analysis 
was initially developed and used for previous particulate matter 
smaller than 10 microns in diameter (PM10) SIP work 
completed by ACHD and discussed in EPA Model Clearinghouse \9\ Memos 
from 1991 through 1994 (91-III-12, 93-III-06, and 94-III-02). (See 
Modeling Protocol Addendum to Appendix A of Pennsylvania's October 3, 
2017 submittal for more information on prior Model Clearinghouse 
memos). The original algorithms were developed for the ACHD 
PM10 SIP workgroup in 1994 and are currently being used by 
ACHD with additional revisions to the BLP Plume Rise program. This 
method is considered an alternative model due to the inclusion of the 
BLP model within the AERMOD dispersion model system (starting with 
AERMOD version 15181) using the BUOYLINE source pathway keyword. ACHD 
began its SIP modeling development for the Area using AERMOD version 
15181 then switched to version 1616r for its final modeling 
demonstration, which was the current regulatory version at the time of 
submittal. Use of an alternative model needs to be approved under 
section 3.2 of Appendix W--Guideline on Air Quality Models--with 
concurrence from EPA's Model Clearinghouse.
---------------------------------------------------------------------------

    \9\ EPA Model Clearinghouse is the central point of consultation 
and coordination within the EPA for reviewing the use of air quality 
models and analytical techniques for demonstrating compliance or 
attainment with the NAAQS in regulatory applications or 
implementation plans. All case-specific approvals of alternative 
models by an EPA Regional Office require consultation and 
concurrence by the Model Clearinghouse, per Section 3.2.2 of the 
Guideline on Air Quality Models (40 CFR part 51 Appendix W).
---------------------------------------------------------------------------

    A demonstration in support of the use of the BLP/AERMOD Hybrid 
approach for source characterization of the coke oven fugitive 
emissions for PM10 was undertaken by ACHD as part of its 
2012 Annual Fine Particle Matter (particulate matter less than 2.5 
microns in diameter, PM2.5) attainment plan preparation. 
While the demonstration was used to support this approach with 
PM10 (simulating dispersion of primary particulate matter), 
in AERMOD both PM10 and SO2 are treated as inert 
pollutants, therefore, they would have similar dispersion 
characteristics and are directly scalable and comparable. Thus, EPA 
finds that this approach is applicable for all primary pollutants 
including SO2. ACHD prepared the analysis and submitted an 
alternative modeling request under section 3.2.2 (b)(2) and (d) of 
Appendix W to EPA Region 3's Regional Administrator on July 27, 2018. 
EPA staff have reviewed ACHD's analysis and found that the BLP/AERMOD 
Hybrid approach provides better model performance of the impacts from 
the coke oven fugitive emissions than the regulatory BUOYLINE source 
methodology in AERMOD. This result is consistent with the dispersion 
model performance analyses ACHD described in Appendix A-2 Modeling 
Protocol Addendum, G and I of Pennsylvania's October 3, 2017 submittal.
    EPA's review and approval of ACHD's analysis supporting the use of 
the BLP/AERMOD Hybrid approach followed the EPA Model Clearinghouse 
concurrence process as prescribed in section 3.2 of Appendix W. 
Following receipt of ACHD's analysis on July 27, 2018, EPA Region 3 
recommended approval of this alternative modeling approach to the EPA 
Model Clearinghouse on August 7, 2018. The EPA Model Clearinghouse 
concurred with Region 3's recommended approval on August 10, 2018. EPA 
Region 3 then approved the use of this alternative model by letter from 
its Regional Administrator to ACHD dated August 16, 2018. EPA is 
providing notice in this rulemaking

[[Page 58213]]

proposal that an alternative modeling approach using the BLP/AERMOD 
Hybrid approach to simulate the fugitive coke oven battery emissions 
was used for ACHD's SO2 attainment plan and that its use was 
approved by EPA. ACHD's request to use this alternative modeling 
approach, EPA Region 3's analysis of ACHD's request, and the EPA Model 
Clearinghouse concurrence is included in the docket for this rulemaking 
action and can be found under Docket ID No. EPA-R03-OAR-2017-0730 and 
online at www.regulations.gov. EPA is taking public comment on 
proposing to approve the SIP based on the approved use of ACHD's 
alternative modeling approach.
    The primary SO2 sources included in the SIP modeling 
demonstration are the Harsco Metals facility and the three USS Mon 
Valley Works facilities--Clairton, Edgar Thomson and Irvin Plants. The 
modeling properly characterized source limits, local meteorological 
data, background concentrations, and provided an adequate model 
receptor grid to capture maximum modeled concentrations. Using the EPA 
conversion factor for the SO2 NAAQS, the final modeled 
design value for the Allegheny Area (196.17 microgram per meter cubed, 
[micro]g/m\3\), is less than 75 ppb.\10\ EPA has reviewed the modeling 
that Pennsylvania submitted to support the attainment demonstration for 
the Allegheny Area and has determined that the modeling is consistent 
with CAA requirements, Appendix W, and EPA's guidance for 
SO2 attainment demonstration modeling as discussed above. 
Therefore, EPA is proposing to determine that the analysis demonstrates 
that the source limits used in the modeling demonstration show 
attainment with the 1-hour SO2 NAAQS. EPA's analysis of the 
modeling is discussed in more detail in EPA's modeling TSD, which can 
be found under Docket ID No. EPA-R03-OAR-2017-0730 and online at 
www.regulations.gov for this rulemaking. EPA proposes to conclude that 
the modeling provided in the attainment plan shows that the Allegheny 
Area will attain the 2010 1-hour primary SO2 NAAQS by the 
attainment date.
---------------------------------------------------------------------------

    \10\ The SO2 NAAQS level is expressed in ppb, but 
AERMOD gives results in micro grams per cubic meter ([micro]g/m\3\). 
The conversion factor for SO2 (at the standard conditions 
applied in the ambient SO2 reference method) is 1 ppb = 
approximately 2.619 [micro]g/m\3\. See Pennsylvania's SO2 
Round 3 Designations proposed TSD at https://www.epa.gov/sites/production/files/2017-08/documents/35_pa_so2_rd3-final.pdf.
---------------------------------------------------------------------------

D. RACM/RACT

    CAA section 172(c)(1) requires that each attainment plan provide 
for the implementation of all reasonably available control measures 
(i.e., RACM) as expeditiously as practicable and shall provide for 
attainment of the NAAQS. EPA interprets RACM, including RACT, under 
section 172, as measures that a state determines to be both reasonably 
available and contribute to attainment as expeditiously as practicable 
``for existing sources in the area.'' In addition, CAA section 
172(c)(6) requires plans to include enforceable emission limitations 
and control measures as may be necessary or appropriate to provide for 
attainment by the attainment date.
    Pennsylvania's October 3, 2017 submittal discusses facility-
specific control measures, namely SO2 emission limits for 
Harsco Metals and for the USS Mon Valley Works facilities--Clairton, 
Edgar Thomson and Irvin Plants, that were developed through the air 
dispersion modeling submitted by ACHD. The modeling analysis is 
discussed in section IV.C. Air Quality Modeling of this proposed 
rulemaking and in the Modeling TSD. ACHD asserts that the combination 
of controls and the resulting emission limits at the three USS 
facilities and Harsco Metals is sufficient for the Allegheny Area to 
meet the SO2 NAAQS and serve as RACT/RACM.
    Controls at the Clairton and Edgar Thomson plants represent the 
majority of SO2 reductions within the Allegheny Area. As 
noted by ACHD, the Clairton Plant is the largest coke plant in North 
America. The Clairton Plant operates 10 coke batteries and produces 
approximately 13,000 tons of coke per day along with approximately 225 
million cubic feet of coke oven gas (COG). The COG is used as fuel at 
all of the Mon Valley Works facilities. At the Clairton Plant, ACHD 
explained in its attainment plan that upgrades to the 100 and 600 
Vacuum Carbonate Units (VCUs) will reduce the content of hydrogen 
sulfide (H2S) in the downriver COG utilized at all Mon 
Valley Works plants. The 100 VCU upgrade was completed in 2016 and the 
600 VCU upgrade will add redundant controls for the downriver COG line. 
Full operation of both upgraded units will be completed on or before 
October 4, 2018 as required by permit. Source monitoring to demonstrate 
continuous efficient operation of the Clairton VCU system is also 
required to be complete by October 4, 2018. In addition, a tail gas 
recycling project at the Shell Claus off-gas Treatment (SCOT) plant 
within the Clairton plant will reroute sulfur-rich gases back into the 
by-products facility at Clairton during planned and unplanned outages 
and will be completed on or before October 4, 2018 as required by 
permit.
    In its modeling analysis, ACHD determined critical emission values 
(CEV) with an hourly average for SO2 sources. However, based 
on the variability in sulfur content of the COG, ACHD determined that 
several sources warrant a limit with a longer-term averaging period. As 
discussed previously, EPA believes that establishment of emission rate 
limits with averaging periods longer than one hour may reasonably be 
found to provide for attainment if specified criteria recommended in 
EPA's 2014 SO2 Nonattainment Guidance are met.
    The objective of ACHD's analysis of the variability of COG sulfur 
content is to determine the adjustment factor that can be multiplied 
times the modeled CEVs to compute longer term limits that will require 
a comparable degree of control as would be required by 1-hour limits at 
the CEVs. EPA's 2014 SO2 Nonattainment Guidance states that 
``. . . air agencies may determine that an area could attain through a 
control strategy that will not significantly change the emission 
distribution (as may be true, for example, for a strategy involving a 
switch to lower sulfur coal with similar sulfur content variability or 
for a strategy involving enhancement of existing control equipment). 
Where the control strategy does not significantly change the 
distribution, the source's current emission distribution may be the 
best indicator of the source's post-control emission distribution.'' In 
this case, the upgrades to the VCU unit at the USS Clairton plant 
reduce the H2S content in the COG but are unlikely to cause 
significant changes in the distribution of emissions, except to the 
extent that installation of redundant sulfur capture systems is likely 
to reduce the frequency and magnitudes of emission spikes from the 
facilities burning this COG. ACHD used the most recent three years of 
operating data (2014-2016) available at the time of its analysis to 
analyze the variability in H2S content in the COG for the 
four primary COG process streams used to deliver fuel to the USS Mon 
Valley Works plants (Unit 1, Unit 2, A Line and B Line). All COG is 
produced and desulfurized at the Clairton plant and then distributed 
via pipeline to the other two plants. USS upgraded its COG sulfur 
removal systems in April 2016, therefore ACHD separately analyzed the 8 
months of data post-control to compare whether the distribution of 
hydrogen sulfide (H2S) content would

[[Page 58214]]

be similar before and after controls. After extrapolating the post-
control data, the distribution of H2S content is similar to 
the distribution before controls thus, ACHD concluded that the use of 
the full 3 years of data is representative of overall variability and, 
that these upgrades are not expected to have a significant effect on 
variability or on the degree of adjustment to yield a comparably 
stringent longer term average limit. Analyzing variability of fuel 
quality is not a direct means of analyzing the variability of emissions 
(which also factors in the variability of the quantity of fuel burned). 
On the other hand, the facilities at issue here have relatively stable 
operations, and a complete analysis would also factor in the degree to 
which the installation of redundant control systems reduces emission 
spikes and thereby reduces variability. For these reasons, EPA believes 
that ACHD's analysis should provide a reasonable approximation of the 
prospective variability of emissions following implementation of the 
controls in the attainment plan and a reasonable approximation of the 
degree of adjustment needed to determine the longer term limits that 
are comparably stringent to the 1-hour limits that would otherwise be 
established.
    In accordance with the methods EPA recommended in Appendix C to its 
2014 SO2 Nonattainment Guidance, adjustment factors were 
determined from the variability in sulfur content in each line and were 
applied to the modeled CEV for the processes using that COG to 
determine an appropriate emission limit with a 30-day averaging period 
that is of comparable stringency to the 1-hour CEV. The 30-day average 
SO2 emission limit adjustment factor is 0.717 for emission 
units burning COG from Unit 1 Line, 0.797 for units burning COG from 
Unit 2 Line, 0.848 for units burning COG from A Line, and 0.834 for 
units burning COG from B Line. As recommended in 2014 SO2 
Nonattainment Guidance, ACHD determined that for sources with a 30-day 
averaging period a supplementary 24-hour limit not to be exceeded for 3 
consecutive days should be applied in order to limit the frequency and 
magnitude of occurrences of elevated emissions. Adjustment factors for 
24-hour SO2 emission limits were calculated for each line 
and applied to the modeled CEV to determine the emission limit with a 
24-hour averaging period. The 24-hour average SO2 emission 
limit adjustment factors for emission units burning COG are 0.914 for 
Unit 1 Line COG, 0.898 for Unit 2 Line COG, 0.927 for A Line COG, and 
0.944 for B Line COG.
    Table 3 shows the modeled CEV, the 30-day and 24-hour average 
adjustment factors and the resulting comparable 30-day and 24-hour 
average SO2 emission rate, calculated by applying the 
adjustment factor to the critical emissions value, for units affected 
by COG sulfur reduction projects and units partially affected by the 
COG controls in combination with other fuels at the Clairton plant. 
Table 3 also shows new SO2 limits for units taking 
reductions to their allowable limits at the Clairton plant.

                                                   Table 3--SO2 Emission Limits for USS Clairton Plant
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                            Adjustment                                      Adjustment     Supplemental
                         Process                           CEV (lbs/hr)   factor (for 30-  New emission      Averaging    factor (for 24-  24-hour limit
                                                                            day limit)    limit (lbs/hr)      period        hour limit)      (lbs/hr)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Boiler 1................................................          142.01           0.834          118.44          30-day           0.944          134.06
                                                              (aggregate
                                                             basis) \11\
Boiler 2................................................
Boiler R1...............................................
Boiler R2...............................................
Boiler T1...............................................
Boiler T2...............................................
Battery 1 Underfiring...................................           14.52           0.717           10.41          30-day           0.914           13.27
Battery 2 Underfiring...................................           12.76           0.717            9.15          30-day           0.914           11.66
Battery 3 Underfiring...................................           14.74           0.717           10.57          30-day           0.914           13.47
Battery 13 Underfiring..................................           17.48           0.797           13.93          30-day           0.898           15.70
Battery 14 Underfiring..................................           17.60           0.797           14.03          30-day           0.898           15.80
Battery 15 Underfiring..................................           23.43           0.797           18.67          30-day           0.898           21.04
Battery 19 Underfiring..................................           36.85           0.797          229.37          30-day           0.898           33.09
Battery 20 Underfiring..................................           33.88           0.797           27.00          30-day           0.898           30.42
B Battery Underfiring...................................           29.82           0.717           21.38          30-day           0.914           27.26
C Battery Underfiring...................................           44.67           0.717           32.03          30-day           0.914           40.83
SCOT Incinerator........................................              24  ..............              24          1-hour
PEC Baghouse 1-3........................................            7.10  ..............            7.10          1-hour
PEC Baghouse 13-15......................................            7.46  ..............            7.46          1-hour
PEC Baghouse 19-20......................................            7.78  ..............            7.78          1-hour
PEC Baghouse B..........................................            7.50  ..............            7.50          1-hour
PEC Baghouse C..........................................            8.65  ..............            8.65          1-hour
Quench Tower 1..........................................            0.75  ..............            0.75          1-hour
Quench Tower B..........................................            4.09  ..............            4.09          1-hour
Quench Tower C..........................................            5.00  ..............            5.00          1-hour
Quench Tower 5A.........................................            7.56  ..............            7.56          1-hour
Quench Tower 7A.........................................            7.21  ..............            7.21          1-hour
Batteries 1-3 Hot Car...................................           10.64  ..............           10.64          1-hour
Batteries 13-15 Hot Car.................................           11.21  ..............           11.21          1-hour
Batteries 19-20 Hot Car.................................           13.73  ..............           13.73          1-hour
C Battery Hot Car.......................................            5.82  ..............            5.82          1-hour
--------------------------------------------------------------------------------------------------------------------------------------------------------
\11\ ACHD ran 16 different modeling scenarios for the various boiler stacks at the Clairton plant and used the worst case boiler impacts in its final
  analysis. Additional information can be found in ACHD's SIP submittal's Appendix I included in the docket for this rulemaking and is available online
  at www.regulations.gov.


[[Page 58215]]

    EPA's guidance advises that, to help assure attainment near sources 
with longer term limits, states should assure that occasions with 
hourly emissions above the CEV are limited in frequency and magnitude. 
The supplemental limits that ACHD has adopted, providing 24-hour 
average limits to supplement the 30-day average limits, serve this 
purpose. To evaluate these limits, ACHD analyzed SO2 
emissions from one source at the Clairton facility (Battery 20 
underfiring) at maximum flow rate and compared hourly emission values 
to the 30-day, 24-hour and CEV limits. ACHD's analysis indicates that, 
for this unit, over a two month span the 30-day limit and 24-hour 
limits were not exceeded while the CEV was exceeded four times. Actual 
flow rate for the months analyzed was 70% of the maximum flowrate in 
which the CEV would have been exceeded twice by less than 2 lb/hr in 
the time period. In addition, ACHD evaluated the hours which were above 
the CEV at either flowrate and the Liberty monitor values ranged from 
0-13 ppb at those times and meteorology was typical for the months. EPA 
does not have the emissions data to make quantitative estimates of the 
expected frequency or magnitude of emissions exceeding the CEVs, but 
EPA believes, particularly with the application of the 24-hour 
supplemental limits, that these occasions are likely to be modest in 
frequency and magnitude. Further details regarding ACHD's longer term 
limits and variability analysis can be found in Appendix D of 
Pennsylvania's October 3, 2017 submittal which can be found under 
Docket ID No. EPA-R03-OAR-2017-0730 and online at www.regulations.gov.
    For these sources with limits based on longer averaging periods, 
H2S content will be measured by a continuous source 
monitoring device and flow meter equipment that measures the actual 
hourly flow of gas. SO2 emissions will then be calculated by 
assuming complete conversion of the combusted H2S. The 
SO2 values will be calculated hourly, averaged over a 24-
hour basis (calendar day) and then averaged over a rolling 30-day 
basis. All sources utilizing a 30-day rolling average also have an 
additional shorter term 24-hour limit which may not be exceeded more 
than three consecutive days. A more detailed discussion of ACHD's 
statistical analysis that was used to develop the proposed 30-day 
average limits and supplemental 24-hour limits for the Allegheny Area 
can be found in Appendix D of Pennsylvania's October 3, 2017 submittal 
found under Docket ID No. EPA-R03-OAR-2017-0730. Additionally, EPA's 
2014 SO2 Nonattainment Guidance and section I. of this 
proposed rulemaking provide an extensive discussion of EPA's rationale 
for concluding that emission limits based on averaging times as long as 
30 days that are appropriately set, reflecting comparable stringency to 
a suitable 1-hour limit, especially when accompanied by supplemental 
limits that help minimize the frequency and magnitude of spikes in 
emissions, can be found to provide for attainment of the 2010 
SO2 NAAQS. In evaluating these longer term averaging times, 
EPA proposes to find that the emission limits with these longer term 
averaging times were appropriately set in accordance with EPA's 2014 
SO2 Nonattainment Guidance and are sufficient for the 
Allegheny Area to attain the 2010 SO2 NAAQS.
    The USS Edgar Thomson plant is an iron and steel making facility 
which mainly produces steel slabs. At the USS Edgar Thomson facility, a 
new stack and a combined flue system is planned for Riley Boilers 1, 2 
and 3. All boilers will exhaust to the new stack which is below good 
engineering practice (GEP) stack height. Specifically, the height of 
this stack, 85 meters, is lower than the formula GEP height based on 
the dimensions of nearby buildings, 97 meters.
    Actual emissions will be reduced as a result of the boilers using 
the lower H2S content COG from the USS Clairton plant in 
combination with other fuels, and thus emissions for the boilers will 
be reduced on an aggregate basis. New emission limits for the boilers 
at the Edgar Thomson plant are listed in Table 4 along with other 
sources with reduced SO2 allowable limits; all of these 
limits are established on a 1-hour basis.\12\
---------------------------------------------------------------------------

    \12\ Subsequent to ACHD's submittal of its attainment plan for 
the Area, ACHD informed EPA that the new stack at the Edgar Thompson 
plant might have different parameters than the ``new stack'' 
parameters included in the attainment plan's attainment 
demonstration modeling. The stack is part of the modeled control 
strategy discussed in sections C and D of this rulemaking. However, 
ACHD has confirmed to EPA (by email) that subsequent modeling with 
the new stack parameters (e.g. location, height, temperature, 
velocity) at the Edgar Thomson plant is consistent with the 
submitted modeling demonstration showing SO2 attainment 
by the attainment date with the same SO2 emission 
limitations in the modeling submitted with ACHD's attainment plan 
for the Area. A copy of this email dated December 8, 2017 with 
technical documentation supporting ACHD's conclusion is included in 
the docket for this rulemaking and is available online at 
www.regulations.gov.

                                                Table 4--SO2 Emission Limits for USS Edgar Thomson Plant
--------------------------------------------------------------------------------------------------------------------------------------------------------
               Process                                                           New * Emission Limit (lbs/hr)
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                    Combustion Units
--------------------------------------------------------------------------------------------------------------------------------------------------------
Boiler 1.............................                                                                                           556.91 (aggregate basis)
Boiler 2.............................
Boiler 3.............................
Blast Furnace 1 Stoves...............                                                                                                              98.50
Blast Furnace 3 Stoves...............                                                                                                              90.00
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                  Non-Combustion Units
--------------------------------------------------------------------------------------------------------------------------------------------------------
Blast Furnace 1 Casthouse (Roof +                                                                                                                   2.01
 Fume)...............................
Blast Furnace 3 Casthouse (Roof +                                                                                                                   1.69
 Fume)...............................
BOP Process (Roof)...................                                                                                                               6.64

[[Page 58216]]

 
Continuous Casting (Roof)............                                                                                                               5.25
Casthouse Baghouse...................                                                                                                              45.10
--------------------------------------------------------------------------------------------------------------------------------------------------------
* New emission limit is equivalent to modeled CEV for Edgar Thomson sources.

    The USS Irvin plant is a secondary steel processing plant which 
receives steel slabs and performs one of several finishing processes on 
the steel slabs. Reductions in SO2 emissions at the USS 
Irvin plant are mainly a result of the COG controls reducing the sulfur 
content in the COG. The 80-inch Hot Strip Mill receives COG via the A 
Line from the Clairton plant while all other units at the Irvin plant 
receive COG via the B Line. Emission limits for units at the USS Irvin 
plant are listed in Table 5.

                                                 Table 5--SO2 Emission Limits for U.S. Steel Irvin Plant
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                            Adjustment                                      Adjustment     Supplemental
                         Process                           CEV (lbs/hr)   factor (for 30-  New emission      Averaging    factor (for 24-  24-hour limit
                                                                            day limit)    limit (lbs/hr)      period        hour limit)      (lbs/hr)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Boiler #1...............................................            9.45           0.834            7.88          30 day           0.944            8.92
Boiler #2...............................................           10.02           0.834            8.36          30 day           0.944            9.46
Boiler #3-4                                                         9.85           0.834            8.21          30 day           0.944            9.30
(aggregate).............................................
80'' Hot Strip Reheat                                             128.10           0.848          108.63          30 day           0.927          118.75
(aggregate).............................................
HPH Annealing Furnaces                                             14.39           0.834              12          30 day           0.944           13.58
(aggregate).............................................
Open Coil Annealing                                                13.79           0.834            11.5          30 day           0.944           13.02
(aggregate).............................................
Continuous Annealing....................................            9.68           0.834            8.07          30 day           0.944            9.14
#1 Galvanizing Line.....................................            0.04  ..............            0.04          1-hour  ..............  ..............
#2 Galvanizing Line.....................................            0.01  ..............            0.01          1-hour  ..............  ..............
--------------------------------------------------------------------------------------------------------------------------------------------------------

    In addition, Harsco Metals (also known as Braddock Recovery Inc) is 
located on the property of the USS Edgar Thomson plant. Harsco uses a 
rotary kiln fired with COG which is supplied by USS Clairton plant. As 
a result of the lower sulfur content in the USS-produced COG, Harsco 
has become subject to a lower SO2 limit of 1.8 lbs/hr as a 
1-hour average for the rotary kiln.
    Emission limits at all four facilities (USS Clairton, Edgar Thomson 
and Irvin Plants and Harsco Metals) were established through 
enforceable installation permits (See Appendices K of Pennsylvania's 
October 3, 2017 SIP submittal). The collective emission limits and 
related compliance parameters (i.e., testing, monitoring, record 
keeping and reporting) have been proposed for incorporation into the 
SIP as part of the attainment plan in accordance with CAA section 172. 
The emission limits for each of the SO2-emitting USS Mon 
Valley facilities are listed in Tables 3, 4 and 5. The compliance 
parameters include continuous process monitoring of H2S 
content and flow rate of the COG at Clairton facility and the four 
lines which feed the Edgar Thompson and Irvin facilities; record-
keeping, reporting, and stack testing requirements at all facilities. 
ACHD affirms that the implementation of new emission limits and 
corresponding compliance parameters at the three USS Mon Valley Works 
facilities and Harsco Metals will enable the Allegheny Area to attain 
and maintain the SO2 NAAQS. The AERMOD modeling analysis 
shows, as discussed in detail in the Modeling TSD, that the emission 
limits listed in Tables 3, 4 and 5 and the limit for Harsco Metals 
(modeling the 1-hour limits where applicable and modeling the 1-hour 
equivalents where longer term average limits apply) are sufficient for 
the Allegheny Area to attain the 1-hour SO2 NAAQS.
    EPA's guidance for longer term average limits is that plans based 
on such limits can be considered to provide for attainment where 
appropriate as long as the longer term limit is comparably stringent to 
the 1-hour limit that would otherwise be set and EPA can have 
reasonable confidence that occasions of emissions above the critical 1-
hour emission rate will be limited in frequency and magnitude. ACHD has 
provided for comparable stringency by computing adjustment factors in 
accordance with the method that EPA recommended in Appendix C of its 
guidance and adopting longer term average limits (where applicable) 
that are adjusted accordingly. Also in accordance with EPA's 
recommendations, ACHD has established supplemental limits that will 
help assure that occasions of emissions above the critical 1-hour 
emission rate will be limited in frequency and magnitude. Therefore, 
EPA believes that ACHD has met EPA's recommended criteria for longer 
term average limits to be part of a plan that provides suitable 
assurances that the area will attain the standard.
    ACHD also evaluated potential RACT at other sources in the 
Allegheny Area including Koppers Inc.--Clairton Plant, Clairton Slag--
West Elizabeth Plant, Eastman Chemical Resins Inc.--Jefferson Plant and 
Kelly Run Sanitation--Forward Township. All sources have less than 5 
tpy of allowable SO2 emissions. ACHD determined that no 
additional controls would be technically or economically feasible for 
the purposes of SO2 RACT

[[Page 58217]]

at these small sources. ACHD also noted that Guardian Industries 
permanently shut down in 2015; therefore, no RACT analysis was 
performed for Guardian Industries. In addition, ACHD examined several 
RACM options for area, nonroad and mobile sources of SO2 in 
the Area and determined no additional controls are needed to provide 
for attainment in the Area, since ACHD's modeling indicates that its 
plan will provide for attainment without reduction of any portion of 
background concentrations attributable to these sources.
    EPA is proposing to approve ACHD's determination that the 
SO2 control strategies at the USS Mon Valley Works 
facilities--Clairton, Edgar Thomson and Irvin plants and Harsco Metals 
constitute RACM/RACT for each source in the Allegheny Area based on the 
modeling analysis previously described and ACHD's evaluation of 
technically and economically feasible controls.
    Pennsylvania has requested that portions of the installation 
permits for the USS Mon Valley Works facilities--Clairton, Edgar 
Thomson and Irvin plants and Harsco Metals be approved into the 
Allegheny County portion of the Pennsylvania SIP. Upon approval, the 
emission limits listed in the installation permits and corresponding 
compliance parameters found in the installation permits for Clairton, 
Edgar Thomson, Irvin and Harsco Metals will become permanent and 
enforceable SIP measures to meet the requirements of the CAA. After 
considering ACHD's submitted information, EPA, therefore, concludes 
Pennsylvania's October 3, 2017, SIP submittal for the Area meets the 
RACM/RACT and emission limitation and other control measure 
requirements of section 172(c) of the CAA.

E. RFP Plan

    Section 172(c)(2) of the CAA requires an attainment plan to include 
a demonstration that shows reasonable further progress (i.e., RFP) for 
meeting air quality standards will be achieved through generally linear 
incremental improvement in air quality. Section 171(1) of the CAA 
defines RFP as ``such annual incremental reductions in emissions of the 
relevant air pollutant as are required by this part (part D) or may 
reasonably be required by EPA for the purpose of ensuring attainment of 
the applicable NAAQS by the applicable attainment date.'' As stated 
originally in the 1994 SO2 Guidelines Document \13\ and 
repeated in the 2014 SO2 Nonattainment Guidance, EPA 
continues to believe that this definition is most appropriate for 
pollutants that are emitted from numerous and diverse sources, where 
the relationship between particular sources and ambient air quality are 
not directly quantified. In such cases, emissions reductions may be 
required from various types and locations of sources. The relationship 
between SO2 and sources is much more defined, and usually 
there is a single step between pre-control nonattainment and post-
control attainment. Therefore, EPA interpreted RFP for SO2 
as adherence to an ambitious compliance schedule in both the 1994 
SO2 Guideline Document and the 2014 SO2 
Nonattainment Guidance. The control measures for attainment of the 2010 
SO2 NAAQS included in Pennsylvania's submittal were modeled 
by ACHD to achieve attainment of the NAAQS. The ACHD permits which 
require these control measures to be effective on or before October 4, 
2018 (including specific emission limits and compliance parameters) 
show the resulting emission reductions to be achieved as expeditiously 
as practicable for the Area. As a result, based on air quality 
modeling, ACHD projected these control measures will yield a sufficient 
reduction in SO2 emissions from the major sources in the 
Allegheny Area to show attainment of the SO2 NAAQS for the 
Allegheny Area. EPA has found ACHD's attainment modeling for the Area 
to be in accordance with CAA requirements. EPA finds the control 
measures proposed will be implemented as expeditiously as practicable 
by October 4, 2018 according to the terms of the permits for the 
affected facilities. Therefore, EPA has determined that Pennsylvania's 
SO2 attainment plan for the Allegheny Area fulfills the RFP 
requirements for the Allegheny Area. EPA proposes to approve 
Pennsylvania's attainment plan with respect to the RFP requirements.
---------------------------------------------------------------------------

    \13\ SO2 Guideline Document, U.S. Environmental 
Protection Agency, Office of Air Quality Planning and Standards, 
Research Triangle Park, NC 27711, EPA-452/R-94-008, February 1994. 
Located at: http://www.epa.gov/ttn/oarpg/t1pgm.html.
---------------------------------------------------------------------------

F. Contingency Measures

    In accordance with section 172(c)(9) of the CAA, contingency 
measures are required as additional measures to be implemented in the 
event that an area fails to meet the RFP requirements or fails to 
attain the standard by its attainment date. These measures must be 
fully adopted rules or control measures that can be implemented quickly 
and without additional EPA or state action if the area fails to meet 
RFP requirements or fails to meet its attainment date, and should 
contain trigger mechanisms and an implementation schedule. However, 
SO2 presents special considerations. As stated in the final 
2010 SO2 NAAQS promulgation on June 22, 2010 (75 FR 35520) 
and in the 2014 SO2 Nonattainment Guidance, EPA concluded 
that because of the quantifiable relationship between SO2 
sources and control measures, it is appropriate that state agencies 
develop a comprehensive program to identify sources of violations of 
the SO2 NAAQS and undertake an aggressive follow-up for 
compliance and enforcement.
    The contingency measures in Pennsylvania's October 3, 2017 
submittal are designed to keep the Allegheny Area from triggering an 
exceedance or violation of the SO2 NAAQS. In the attainment 
plan, ACHD states that if an ambient air quality monitor measures 
enough exceedances in a consecutive three-year period that would cause 
a design value to exceed the 75 ppb standard, ACHD would conduct a 
thorough analysis in order to identify the sources of the violation and 
bring the area back into compliance with the NAAQS. ACHD states that 
the root cause analysis will begin immediately upon verification of a 
violation, will include analysis of source and meteorological 
conditions contributing to the violation, and will take no longer than 
10 days to complete. In its plan, sources identified by ACHD as most 
likely contributing to the violation will have 10 days from 
notification to submit a written system audit report which details the 
operating parameters of all SO2 emission sources for the 
four 5-day periods up to and including the dates which the monitor 
registered exceedances of the SO2 NAAQS. According to the 
attainment plan, sources must recommend SO2 control 
strategies for each affected unit in the audit report. Once ACHD 
receives the audit report(s), a 30-day evaluation period will begin in 
which ACHD will investigate the audit findings and recommended control 
strategies. The 30-day evaluation period will be followed by a 30-day 
consultation period with the sources. Additional control measures will 
be implemented as expeditiously as possible to bring the Area back into 
compliance. If a permit modification is necessary, ACHD has the 
statutory authority under ACHD Rules and Regulations, Article XXI--Air 
Pollution Control to amend and issue a final permit. Any new emission 
limits would also be submitted to EPA as a SIP revision. In addition, 
ACHD has the regulatory authority to take any action it deems necessary 
or proper for the effective enforcement of rules and regulations; such 
actions include the

[[Page 58218]]

issuance of orders (i.e., enforcement orders and orders to take 
corrective action to address air pollution or the danger of air 
pollution from a source) and the assessment of civil penalties. ACHD's 
regulations for enforcement, ACHD Article XXI, Part I, sections 
2109.01-2109.06 and 2109.10, provide ACHD authority to enforce its 
regulations, permits and orders. Pursuant to these regulations, ACHD 
has authority, inter alia, to inspect facilities, seek penalties for 
violations, enter enforcement orders, and revoke permits. These 
regulations are included in the Pennsylvania SIP. See 67 FR 68935 
(November 14, 2002).
    EPA finds that ACHD has a comprehensive program included in the 
Pennsylvania SIP to identify sources of violations of the 
SO2 NAAQS and to undertake an aggressive follow up for 
compliance and enforcement. Therefore, EPA proposes that the 
contingency measures submitted by Pennsylvania follow the 2014 
SO2 Nonattainment Guidance and meet the section 172(c)(9) 
requirements.

G. New Source Review \14\
---------------------------------------------------------------------------

    \14\ The CAA new source review (NSR) program is composed of 
three separate programs: Prevention of significant deterioration 
(PSD), NNSR, and Minor NSR. PSD is established in part C of title I 
of the CAA and applies in areas that meet the NAAQS--``attainment 
areas''--as well as areas where there is insufficient information to 
determine if the area meets the NAAQS--``unclassifiable areas.'' The 
NNSR program is established in part D of title I of the CAA and 
applies in areas that are not in attainment of the NAAQS--
``nonattainment areas.'' The Minor NSR program addresses 
construction or modification activities that do not qualify as 
``major'' and applies regardless of the designation of the area in 
which a source is located. Together, these programs are referred to 
as the NSR programs. Section 173 of the CAA lays out the NNSR 
program for preconstruction review of new major sources or major 
modifications to existing sources, as required by CAA section 
172(c)(5). The programmatic elements for NNSR include, among other 
things, compliance with the lowest achievable emissions rate and the 
requirement to obtain emissions offsets.
---------------------------------------------------------------------------

    Section 172(c)(5) of the CAA requires that an attainment plan 
require permits for the construction and operation of new or modified 
major stationary sources in a nonattainment area. In Allegheny County, 
NNSR procedures and conditions for which new major stationary sources 
or major modifications may obtain a preconstruction permit are 
stipulated in the ACHD Rules and Regulations, Article XXI, Air 
Pollution Control, Sec.  2102.06, ``Major Sources Locating in or 
Impacting a Nonattainment Area'' which was previously approved into the 
Pennsylvania SIP, with the most recent revision effective March 30, 
2015 (80 FR 16570). ACHD Rules and Regulations, Article XXI, Air 
Pollution Control, Sec.  2102.06 also incorporates by reference 
applicable provisions of PADEP's NNSR regulations codified at 25 Pa. 
Code Chapter 127, Subchapter E. PADEP's NNSR regulations in 25 Pa. Code 
Chapter 127, Subchapter E were previously approved into the 
Pennsylvania SIP, with the most recent revision updating the 
regulations to meet EPA's 2002 NSR reform regulations effective on May 
14, 2012 (77 FR 28261). A discussion of the specific PADEP provisions 
incorporated by reference into ACHD Article XXI can be found in 
Pennsylvania's October 3, 2017 submittal found under Docket ID No. EPA-
R03-OAR-2017-0730. These rules provide for appropriate NNSR permitting 
as required by CAA sections 172(c)(5) and 173 and 40 CFR 51.165 for 
SO2 sources undergoing construction or major modification in 
the Allegheny Area without need for modification of the approved rules. 
Therefore, EPA concludes that Allegheny County's SIP-approved NNSR 
program meets the requirements of section 172(c)(5) for this Area.

VI. EPA's Proposed Action

    EPA is proposing to approve Pennsylvania's attainment plan SIP 
revision for the Allegheny Area, as submitted through ACHD and PADEP to 
EPA on October 3, 2017, for the purpose of demonstrating attainment of 
the 2010 1-hour SO2 NAAQS. Specifically, EPA is proposing to 
approve the base year emissions inventory, a modeling demonstration of 
SO2 attainment, an analysis of RACM/RACT, a RFP plan, and 
contingency measures for the Allegheny Area and is proposing that the 
Pennsylvania SIP revision has met the requirements for NNSR for the 
2010 1-hour SO2 NAAQS. Additionally, EPA is proposing to 
approve into the Pennsylvania SIP specific SO2 emission 
limits and compliance parameters in permits established for the 
SO2 sources impacting the Allegheny Area.
    EPA has determined that Pennsylvania's SO2 attainment 
plan for the 2010 1-hour SO2 NAAQS for the Allegheny Area 
meets the applicable requirements of the CAA and EPA's 2014 
SO2 Nonattainment Guidance. Thus, EPA is proposing to 
approve Pennsylvania's attainment plan for the Allegheny Area as 
submitted on October 3, 2017. EPA's analysis for this proposed action 
is discussed in Section V of this proposed rulemaking. EPA is 
soliciting public comments on the issues discussed in this document. 
These comments will be considered before taking final action. Final 
approval of this SIP submittal will remove EPA's duty to implement a 
FIP for this Area.

VII. 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 portions of the installation permits issued by ACHD with USS 
facilities at Clairton, Edgar Thomson and Irvin and with Harsco Metals. 
This includes emission limits and associated compliance parameters, 
recording-keeping and reporting. EPA has made, and will continue to 
make, these materials generally available through http://www.regulations.gov and at the EPA Region III Office (please contact 
the person identified in the ``For Further Information Contact'' 
section of this proposed rulemaking for more information).

VIII. 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 proposed 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

[[Page 58219]]

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, this proposed rule, concerning the SO2 
attainment plan for the Allegheny Area in Pennsylvania, does not have 
tribal implications as specified by Executive Order 13175 (65 FR 67249, 
November 9, 2000), because the SIP is not approved to apply in Indian 
country located in the state, and EPA notes that it will not impose 
substantial direct costs on tribal governments or preempt tribal law.

List of Subjects in 40 CFR Part 52

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

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

    Dated: November 1, 2018.
Cosmo Servidio,
Regional Administrator, Region III.
[FR Doc. 2018-25079 Filed 11-16-18; 8:45 am]
 BILLING CODE 6560-50-P



                                                58206                Federal Register / Vol. 83, No. 223 / Monday, November 19, 2018 / Proposed Rules

                                                which is the product of the                             Drafting Information                                  § 300.10 Renewal of enrollment of enrolled
                                                approximately 22,781 individuals and                                                                          retirement plan agent fee.
                                                                                                           The principal author of these
                                                the $37 increase in the fee. Accordingly,               regulations is Mark Shurtliff, Office of              *     *     *    *      *
                                                the rule is not expected to have a                      the Associate Chief Counsel (Procedure                  (b) Fee. The fee for renewal of
                                                significant economic impact on a                        and Administration). Other personnel                  enrollment as an enrolled retirement
                                                substantial number of small entities,                   from the Treasury Department and the                  plan agent with the IRS is $67.
                                                and a regulatory flexibility analysis is                IRS participated in their development.                *     *     *    *      *
                                                not required.                                                                                                   (d) Applicability date. This section
                                                                                                        List of Subjects in 26 CFR Part 300                   applies 30 days after the date of
                                                  It is not anticipated that the increase
                                                in user fee that is paid every three years                Reporting and recordkeeping                         publication of a Treasury Decision
                                                and averages to $12.33 per year will                    requirements, User fees.                              adopting this rule as a final regulation
                                                negatively affect enrollment, which has                                                                       in the Federal Register.
                                                                                                        Proposed Amendments to the
                                                historically remained steady as user fee                Regulations                                           §§ 300.12 and 300.13 [Redesignated as
                                                amounts have changed. Pursuant to                                                                             §§ 300.11 and 300.12]
                                                section 7805(f), this notice of proposed                  Accordingly, 26 CFR part 300 is
                                                                                                        proposed to be amended as follows:                    ■ Par. 7. Redesignate §§ 300.12 and
                                                rulemaking has been submitted to the                                                                          300.13 as §§ 300.11 and 300.12.
                                                Chief Counsel for Advocacy of the Small                 PART 300—USER FEES
                                                Business Administration for comment                                                                           Kirsten Wielobob,
                                                on its impact on small business.                        ■ Paragraph. 1. The authority citation                Deputy Commissioner for Services and
                                                                                                        for part 300 continues to read as                     Enforcement.
                                                Comments and Public Hearing                                                                                   [FR Doc. 2018–25210 Filed 11–15–18; 4:15 pm]
                                                                                                        follows:
                                                                                                                                                              BILLING CODE 4830–01–P
                                                   Before these proposed amendments to                      Authority: 31 U.S.C. 9701.
                                                the regulations are adopted as final
                                                regulations, consideration will be given                § 300.0    [Amended]
                                                to any comments that are submitted                      ■ Par. 2. Section 300.0 is amended by                 ENVIRONMENTAL PROTECTION
                                                timely to the IRS as prescribed in the                  removing paragraph (b)(10) and                        AGENCY
                                                preamble under the ADDRESSES section.                   redesignating paragraphs (b)(11) through
                                                                                                        (13) as paragraphs (b)(10) through (12).              40 CFR Part 52
                                                The Treasury Department and the IRS
                                                request comments on all aspects of the                  ■ Par. 3. Section 300.5 is amended by                 [EPA–R03–OAR–2017–0730; FRL–9986–63–
                                                proposed regulations. All comments                      revising paragraphs (b) and (d) to read               Region 3]
                                                submitted will be made available at                     as follows:
                                                                                                                                                              Approval and Promulgation of Air
                                                www.regulations.gov or upon request.                    § 300.5    Enrollment of enrolled agent fee.          Quality Implementation Plans;
                                                   A public hearing has been scheduled                  *     *     *    *      *                             Pennsylvania; Attainment Plan for the
                                                for January 24, 2019, beginning at 10:00                  (b) Fee. The fee for initially enrolling            Allegheny, Pennsylvania
                                                a.m. in the Main Auditorium of the                      as an enrolled agent with the IRS is $67.             Nonattainment Area for the 2010 Sulfur
                                                Internal Revenue Service Building, 1111                 *     *     *    *      *                             Dioxide Primary National Ambient Air
                                                Constitution Avenue NW, Washington,                       (d) Applicability date. This section                Quality Standard
                                                DC 20224. Due to building-security                      applies 30 days after the date of
                                                procedures, visitors must enter at the                                                                        AGENCY:  Environmental Protection
                                                                                                        publication of a Treasury Decision
                                                Constitution Avenue entrance. All                                                                             Agency (EPA).
                                                                                                        adopting this rule as a final regulation
                                                visitors must present photo                             in the Federal Register.                              ACTION: Proposed rule.
                                                identification to enter the building.                   ■ Par. 4. Section 300.6 is amended by
                                                                                                                                                              SUMMARY:    The Environmental Protection
                                                Because of access restrictions, visitors                revising paragraphs (b) and (d) to read               Agency (EPA) is proposing to approve a
                                                will not be admitted beyond the                         as follows:                                           state implementation plan (SIP)
                                                immediate entrance area more than 30
                                                                                                        § 300.6 Renewal of enrollment of enrolled             revision, submitted by the Pennsylvania
                                                minutes before the hearing starts. For
                                                                                                        agent fee.                                            Department of Environmental Protection
                                                information about having your name
                                                                                                        *     *     *    *      *                             (PADEP) on behalf of the Allegheny
                                                placed on the building access list to
                                                                                                          (b) Fee. The fee for renewal of                     County Health Department (ACHD), to
                                                attend the hearing, see the FOR FURTHER
                                                                                                        enrollment as an enrolled agent with the              EPA on October 3, 2017, for the purpose
                                                INFORMATION CONTACT section of this
                                                                                                        IRS is $67.                                           of providing for attainment of the 2010
                                                preamble.
                                                                                                                                                              sulfur dioxide (SO2) primary national
                                                   The rules of § 601.601(a)(3) apply to                *     *     *    *      *
                                                                                                                                                              ambient air quality standard (NAAQS)
                                                the hearing. Persons who wish to                          (d) Applicability date. This section
                                                                                                                                                              in the Allegheny, Pennsylvania SO2
                                                present oral comments at the hearing                    applies 30 days after the date of
                                                                                                                                                              nonattainment area (hereafter referred to
                                                must submit written or electronic                       publication of a Treasury Decision
                                                                                                                                                              as the ‘‘Allegheny Area’’ or ‘‘Area’’). The
                                                comments and an outline of the topics                   adopting this rule as a final regulation
                                                                                                                                                              major sources of SO2 in the Allegheny
                                                to be discussed and the time to be                      in the Federal Register.
                                                                                                                                                              Area are the Harsco Metals facility and
                                                devoted to each topic by January 18,                    § 300.10    [Removed]                                 the facilities which comprise the U.S.
khammond on DSK30JT082PROD with PROPOSAL




                                                2019. A period of 10 minutes will be                    ■   Par. 5. Section 300.10 is removed.                Steel (USS) Mon Valley Works: Clairton,
                                                allocated to each person for making                                                                           Edgar Thomson and Irvin Plants. The
                                                comments. An agenda showing the                         § 300.11 [Redesignated as § 300.10 and                Pennsylvania SIP submission is an
                                                scheduling of the speakers will be                      Amended]                                              attainment plan which includes the base
                                                prepared after the deadline for receiving               ■ Par. 6. Redesignate § 300.11 as                     year emissions inventory, an analysis of
                                                outlines has passed. Copies of the                      § 300.10 and amend newly redesignated                 the reasonably available control
                                                agenda will be available free of charge                 § 300.10 by revising paragraphs (b) and               technology (RACT) and reasonably
                                                at the hearing.                                         (d) to read as follows:                               available control measure (RACM)


                                           VerDate Sep<11>2014   16:52 Nov 16, 2018   Jkt 247001   PO 00000   Frm 00016   Fmt 4702   Sfmt 4702   E:\FR\FM\19NOP1.SGM   19NOP1


                                                                     Federal Register / Vol. 83, No. 223 / Monday, November 19, 2018 / Proposed Rules                                                     58207

                                                requirements, enforceable emission                      IV. Pennsylvania’s Attainment Plan                    data to support a nonattainment
                                                limitations and control measures, a                          Submittal for the Allegheny Area                 designation.2
                                                reasonable further progress (RFP) plan,                 V. EPA’s Analysis of Pennsylvania’s                      Effective on October 4, 2013, the
                                                a modeling demonstration of SO2                              Attainment Plan Submittal for the                Allegheny Area was designated as
                                                                                                             Allegheny Area                                   nonattainment for the 2010 SO2 NAAQS
                                                attainment, a nonattainment New                           A. Pollutants Addressed
                                                Source Review (NNSR) permit program,                      B. Emissions Inventory Requirements
                                                                                                                                                              for an area that encompasses the
                                                and contingency measures for the                          C. Air Quality Modeling                             primary SO2 emitting sources of the
                                                Allegheny Area. As part of approving                      D. RACM/RACT                                        Harsco Metals facility and the USS Mon
                                                the attainment plan, EPA is also                          E. RFP Plan                                         Valley Works (Clairton, Edgar Thomson
                                                proposing to approve new SO2 emission                     F. Contingency Measures                             and Irvin Plants). The Allegheny Area is
                                                limits and associated compliance                          G. New Source Review                                comprised of a portion of Allegheny
                                                parameters for USS Clairton, Edgar                      VI. EPA’s Proposed Action                             County which includes the City of
                                                Thomson and Irvin Plants and the                        VII. Incorporation by Reference                       Clairton, City of Duquesne, City of
                                                                                                        VIII. Statutory and Executive Order Reviews           McKeesport, Borough of Braddock,
                                                Harsco Metals facility into the
                                                Allegheny County portion of the                         I. Background for EPA’s Proposed                      Borough of Dravosburg, Borough of East
                                                Pennsylvania SIP. This action is being                  Action                                                McKeesport, Borough of East Pittsburgh,
                                                taken under the Clean Air Act (CAA).                                                                          Borough of Elizabeth, Borough of
                                                                                                           On June 2, 2010, the EPA                           Glassport, Borough of Jefferson Hills,
                                                DATES: Written comments must be                         Administrator signed a final rule                     Borough of Liberty, Borough of Lincoln,
                                                received on or before December 19,                      establishing a new SO2 primary NAAQS                  Borough of North Braddock, Borough of
                                                2018.                                                   as a 1-hour standard of 75 parts per                  Pleasant Hills, Borough of Port Vue,
                                                                                                        billion (ppb), based on a 3-year average              Borough of Versailles, Borough of Wall,
                                                ADDRESSES:   Submit your comments,
                                                                                                        of the annual 99th percentile of daily                Borough of West Elizabeth, Borough of
                                                identified by Docket ID No. EPA–R03–
                                                                                                        maximum 1-hour average                                West Mifflin, Elizabeth Township,
                                                OAR–2017–0730 at http://
                                                                                                        concentrations. See 75 FR 35520 (June                 Forward Township, and North
                                                www.regulations.gov, or via email to
                                                                                                        22, 2010), 40 CFR 50.17. This action                  Versailles Township in Pennsylvania.
                                                spielberger.susan@epa.gov. For
                                                                                                        also revoked the existing 1971 annual                 The October 4, 2013 final designation
                                                comments submitted at Regulations.gov,
                                                                                                        standard and 24-hour standards, subject               triggered a requirement for
                                                follow the online instructions for
                                                                                                        to certain conditions.1 EPA established               Pennsylvania to submit a SIP revision
                                                submitting comments. Once submitted,
                                                                                                        the NAAQS based on significant                        with an attainment plan for how the
                                                comments cannot be edited or removed
                                                                                                        evidence and numerous health studies                  Area would attain the 2010 SO2 NAAQS
                                                from Regulations.gov. For either manner
                                                                                                        demonstrating that serious health effects             as expeditiously as practicable, but no
                                                of submission, EPA may publish any
                                                                                                        are associated with short-term                        later than October 4, 2018, in
                                                comment received to its public docket.
                                                                                                        exposures to SO2 emissions ranging                    accordance with CAA sections 172 and
                                                Do not submit electronically any
                                                                                                        from 5 minutes to 24 hours with an                    191–192.
                                                information you consider to be
                                                                                                        array of adverse respiratory effects                     For a number of areas, including the
                                                confidential business information (CBI)
                                                                                                        including narrowing of the airways                    Allegheny Area, EPA published a notice
                                                or other information whose disclosure is
                                                                                                        which can cause difficulty breathing                  on March 18, 2016, that Pennsylvania
                                                restricted by statute. Multimedia
                                                                                                        (bronchoconstriction) and increased                   and other pertinent states had failed to
                                                submissions (audio, video, etc.) must be
                                                                                                        asthma symptoms. For more                             submit the required SO2 attainment plan
                                                accompanied by a written comment.
                                                                                                        information regarding the health                      by this submittal deadline. See 81 FR
                                                The written comment is considered the
                                                                                                        impacts of SO2, please refer to the June              14736. This finding initiated a deadline
                                                official comment and should include
                                                                                                        22, 2010, final rulemaking. See 75 FR                 under CAA section 179(a) for the
                                                discussion of all points you wish to
                                                                                                        35520. Following promulgation of a new                potential imposition of new source
                                                make. EPA will generally not consider
                                                                                                        or revised NAAQS, EPA is required by                  review and highway funding sanctions.
                                                comments or comment contents located
                                                                                                        the CAA to designate areas throughout                 However, pursuant to Pennsylvania’s
                                                outside of the primary submission (i.e.
                                                                                                        the United States as attaining or not                 submittal of October 3, 2017, and EPA’s
                                                on the web, cloud, or other file sharing
                                                                                                        attaining the NAAQS; this designation                 subsequent letter dated October 6, 2017
                                                system). For additional submission
                                                                                                        process is described in section 107(d)(1)             to Pennsylvania finding the submittal
                                                methods, please contact the person
                                                                                                        of the CAA. On August 5, 2013, EPA                    complete and noting the stopping of the
                                                identified in the FOR FURTHER
                                                                                                        promulgated initial air quality                       sanctions’ deadline, these sanctions
                                                INFORMATION CONTACT section. For the
                                                                                                        designations for 29 areas for the 2010                under section 179(a) will not be
                                                full EPA public comment policy,
                                                                                                        SO2 NAAQS (78 FR 47191), which                        imposed as a consequence of
                                                information about CBI or multimedia
                                                                                                        became effective on October 4, 2013,                  Pennsylvania’s having missed the
                                                submissions, and general guidance on
                                                                                                        based on violating air quality                        original deadline. Additionally, under
                                                making effective comments, please visit
                                                                                                        monitoring data for calendar years                    CAA section 110(c), the finding triggers
                                                http://www2.epa.gov/dockets/
                                                                                                        2009–2011, where there was sufficient                 a requirement that EPA promulgate a
                                                commenting-epa-dockets.
                                                                                                                                                              federal implementation plan (FIP)
                                                FOR FURTHER INFORMATION CONTACT:                           1 With certain exceptions, EPA’s June 22, 2010
                                                                                                                                                              within two years of the effective date of
                                                Leslie Jones Doherty, (215) 814–3409, or                final action revoked the two 1971 primary 24-hour     the finding unless, by that time, the
                                                by email at jones.leslie@epa.gov.                       standard of 140 ppb and the annual standard of 30
                                                                                                                                                              state has made the necessary complete
khammond on DSK30JT082PROD with PROPOSAL




                                                                                                        ppb because they were determined not to add
                                                SUPPLEMENTARY INFORMATION:                              additional public health protection given a 1-hour
                                                                                                        standard at 75 ppb. See 75 FR 35520. However, the       2 EPA is continuing its designation efforts for the
                                                Table of Contents                                       secondary 3-hour SO2 standard was retained.           2010 SO2 NAAQS. Pursuant to a court-order issued
                                                                                                        Because Allegheny County has already been             on March 2, 2015, by the U.S. District Court for the
                                                I. Background for EPA’s Proposed Action                 designated for the 2010 1-hour SO2 NAAQS and          Northern District of California, EPA must complete
                                                II. Requirements for SO2 Nonattainment                  was neither designated nonattainment nor subject      the remaining designations for the rest of the
                                                      Plans                                             to a SIP call for the 1971 primary standards, these   country on a schedule that contains three specific
                                                III. Attainment Demonstration and Longer                standards have been revoked for this area. See 40     deadlines. Sierra Club, et al. v. Environmental
                                                      Term Averaging                                    CFR 50.4(e).                                          Protection Agency, 13–cv–03953–SI (2015).



                                           VerDate Sep<11>2014   16:52 Nov 16, 2018   Jkt 247001   PO 00000   Frm 00017   Fmt 4702   Sfmt 4702   E:\FR\FM\19NOP1.SGM   19NOP1


                                                58208                Federal Register / Vol. 83, No. 223 / Monday, November 19, 2018 / Proposed Rules

                                                submittal and EPA has approved the                      requirements have been met. Under                     expressed as short-term average limits
                                                submittal as meeting applicable                         CAA sections 110(l) and 193, EPA may                  (e.g., addressing emissions averaged
                                                requirements.                                           not approve a SIP that would interfere                over one or three hours), but also
                                                                                                        with any applicable requirement                       describes the option to utilize emission
                                                II. Requirements for SO2
                                                                                                        concerning NAAQS attainment and                       limits with longer averaging times of up
                                                Nonattainment Area Plans
                                                                                                        RFP, or any other applicable                          to 30 days so long as the state meets
                                                   Attainment plans must meet the                       requirement, and no requirement in                    various suggested criteria. See 2014 SO2
                                                applicable requirements of the CAA,                     effect (or required to be adopted by an               Nonattainment Guidance, pp. 22 to 39.
                                                and specifically CAA sections 172, 191,                 order, settlement, agreement, or plan in              The guidance recommends that—should
                                                and 192. The required components of an                  effect before November 15, 1990) in any               states and sources utilize longer
                                                attainment plan submittal are listed in                 area which is a nonattainment area for                averaging times—the longer term
                                                section 172(c) of Title 1, part D of the                any air pollutant, may be modified in                 average limit should be set at an
                                                CAA. The EPA’s regulations governing                    any manner unless it insures equivalent               adjusted level that reflects a stringency
                                                nonattainment SIPs are set forth at 40                  or greater emission reductions of such                comparable to the 1-hour average limit
                                                CFR part 51, with specific procedural                   air pollutant.                                        at the critical emission value shown to
                                                requirements and control strategy                                                                             provide for attainment that the plan
                                                requirements residing at subparts F and                 III. Attainment Demonstration and
                                                                                                                                                              otherwise would have set.
                                                G, respectively. Soon after Congress                    Longer Term Averaging                                    The 2014 SO2 Nonattainment
                                                enacted the 1990 Amendments to the                         CAA section 172(c)(1) directs states               Guidance provides an extensive
                                                CAA, EPA issued comprehensive                           with areas designated as nonattainment                discussion of EPA’s rationale for
                                                guidance on SIPs, in a document                         to demonstrate that the submitted plan                positing that appropriately set
                                                entitled the ‘‘General Preamble for the                 provides for attainment of the NAAQS.                 comparably stringent limitations based
                                                Implementation of Title I of the Clean                  40 CFR part 51, subpart G further                     on averaging times as long as 30 days
                                                Air Act Amendments of 1990,’’                           delineates the control strategy                       can be found to provide for attainment
                                                published at 57 FR 13498 (April 16,                     requirements that SIPs must meet, and                 of the 2010 SO2 NAAQS. In evaluating
                                                1992) (General Preamble). Among other                   EPA has long required that all SIPs and               this option, EPA considered the nature
                                                things, the General Preamble addressed                  control strategies reflect four                       of the standard, conducted detailed
                                                SO2 SIPs and fundamental principles for                 fundamental principles of                             analyses of the impact of use of 30-day
                                                SIP control strategies. Id. at 13545–49,                quantification, enforceability,                       average limits on the prospects for
                                                13567–68. On April 23, 2014, EPA                        replicability, and accountability.                    attaining the standard, and carefully
                                                issued recommended guidance                             General Preamble, at 13567–68. SO2                    reviewed how best to achieve an
                                                (hereafter 2014 SO2 Nonattainment                       attainment plans must consist of two                  appropriate balance among the various
                                                Guidance) for how state submissions                     components: (1) Emission limits and                   factors that warrant consideration in
                                                could address the statutory                             other control measures that assure                    judging whether a state’s plan provides
                                                requirements for SO2 attainment plans.3                 implementation of permanent,                          for attainment. Id. at pp. 22 to 39. See
                                                In this guidance, EPA described the                     enforceable and necessary emission                    also id. at Appendices B, C, and D.
                                                statutory requirements for an attainment                controls, and (2) a modeling analysis                    As specified in 40 CFR 50.17(b), the
                                                plan, which includes: An accurate base                  which meets the requirements of 40 CFR                1-hour primary SO2 NAAQS is met at an
                                                year emissions inventory of current                     part 51, Appendix W which                             ambient air quality monitoring site
                                                emissions for all sources of SO2 within                 demonstrates that these emission limits               when the 3-year average of the annual
                                                the nonattainment area (172(c)(3)); an                  and control measures provide for timely               99th percentile of daily maximum 1-
                                                attainment demonstration that includes                  attainment of the primary SO2 NAAQS                   hour average concentrations is less than
                                                a modeling analysis showing that the                    as expeditiously as practicable, but by               or equal to 75 ppb. In a year with 365
                                                enforceable emissions limitations and                   no later than the attainment date for the             days of valid monitoring data, the 99th
                                                other control measures taken by the                     affected area. In all cases, the emission             percentile would be the fourth highest
                                                state will provide for expeditious                      limits and control measures must be                   daily maximum 1-hour value. The 2010
                                                attainment of the NAAQS (172(c)); RFP                   accompanied by appropriate methods                    SO2 NAAQS, including this form of
                                                (172(c)(2)); implementation of RACM,                    and conditions to determine compliance                determining compliance with the
                                                including RACT (172(c)(1)); NNSR                        with the respective emission limits and               standard, was upheld by the U.S. Court
                                                requirements (172(c)(5)); and adequate                  control measures and must be                          of Appeals for the District of Columbia
                                                contingency measures for the affected                   quantifiable (i.e., a specific amount of              Circuit in Nat’l Envt’l Dev. Ass’n’s Clean
                                                area (172(c)(9)). A synopsis of these                   emission reduction can be ascribed to                 Air Project v. EPA, 686 F.3d 803 (D.C.
                                                requirements is also provided in the                    the measures), fully enforceable                      Cir. 2012). Because the standard has this
                                                notice of proposed rulemaking on the                    (specifying clear, unambiguous and                    form, a single exceedance does not
                                                Illinois SO2 nonattainment plans,                       measurable requirements for which                     create a violation of the standard.
                                                published on October 5, 2017 at 82 FR                   compliance can be practicably                         Instead, at issue is whether a source
                                                46434.                                                  determined), replicable (the procedures               operating in compliance with a properly
                                                   In order for EPA to fully approve a                  for determining compliance are                        set longer term average could cause
                                                SIP as meeting the requirements of CAA                  sufficiently specific and non-subjective              exceedances, and if so the resulting
                                                sections 110, 172 and 191–192 and                       so that two independent entities                      frequency and magnitude of such
                                                EPA’s regulations at 40 CFR part 51, the                applying the procedures would obtain                  exceedances, and in particular whether
khammond on DSK30JT082PROD with PROPOSAL




                                                SIP for the affected area needs to                      the same result), and accountable                     EPA can have reasonable confidence
                                                demonstrate to EPA’s satisfaction that                  (source specific limits must be                       that a properly set longer term average
                                                each of the aforementioned                              permanent and must reflect the                        limit will provide that the average
                                                                                                        assumptions used in the SIP                           fourth highest daily maximum value
                                                   3 See ‘‘Guidance for 1-Hour SO Nonattainment
                                                                                 2                      demonstrations). EPA’s 2014 SO2                       will be at or below 75 ppb. A synopsis
                                                Area SIP Submissions’’ (April 23, 2014), available
                                                at https://www.epa.gov/sites/production/files/2016-
                                                                                                        Nonattainment Guidance recommends                     of how EPA judges whether such plans
                                                06/documents/20140423guidance_nonattainment_            that the emission limits established for              ‘‘provide for attainment,’’ based on
                                                sip.pdf.                                                the attainment demonstration be                       modeling of projected allowable


                                           VerDate Sep<11>2014   16:52 Nov 16, 2018   Jkt 247001   PO 00000   Frm 00018   Fmt 4702   Sfmt 4702   E:\FR\FM\19NOP1.SGM   19NOP1


                                                                     Federal Register / Vol. 83, No. 223 / Monday, November 19, 2018 / Proposed Rules                                             58209

                                                emissions and in light of the NAAQS’                    takes the source’s emissions profile into             concentration, which allows one to
                                                form for determining attainment at                      account. As a result, EPA expects either              assume a linear relationship between
                                                monitoring sites follows.                               form of emission limit to yield                       emissions and air quality. (A nonzero
                                                   For SO2 plans based on 1-hour                        comparable air quality.                               background concentration would make
                                                emission limits, the standard approach                     Second, from a more theoretical                    the mathematics more difficult but
                                                is to conduct modeling using fixed                      perspective, EPA has compared the                     would give similar results.) Air quality
                                                emission rates. The maximum emission                    likely air quality with a source having               will depend on what emissions happen
                                                rate that would be modeled to result in                 maximum allowable emissions under an                  on what critical hours, but suppose that
                                                attainment (i.e., in an ‘‘average year’’ 4              appropriately set longer term limit, as               emissions at the relevant times on these
                                                shows three, not four days with                         compared to the likely air quality with               5 days are 800 pounds/hour (lb/hr),
                                                maximum hourly levels exceeding 75                      the source having maximum allowable                   1100 pounds per hour, 500 pounds per
                                                ppb) is labeled the ‘‘critical emission                 emissions under the comparable 1-hour                 hour, 900 pounds per hour, and 1200
                                                value.’’ The modeling process for                       limit. In this comparison, in the 1-hour              pounds per hour, respectively. (This is
                                                identifying this critical emissions value               average limit scenario, the source is                 a conservative example because the
                                                inherently considers the numerous                       presumed at all times to emit at the                  average of these emissions, 900 pounds
                                                variables that affect ambient                           critical emission level, and in the longer            per hour, is well over the 30-day average
                                                concentrations of SO2, such as                          term average limit scenario, the source               emission limit.) These emissions would
                                                meteorological data, background                         is presumed occasionally to emit more                 result in daily maximum 1-hour
                                                concentrations, and topography. In the                  than the critical emission value but on               concentrations of 80 ppb, 99 ppb, 40
                                                standard approach, the state would then                 average, and presumably at most times,                ppb, 67.5 ppb, and 84 ppb. In this
                                                provide for attainment by setting a                     to emit well below the critical emission              example, the fifth day would have an
                                                continuously applicable 1-hour                          value. In an ‘‘average year,’’ compliance             exceedance that would not otherwise
                                                emission limit at this critical emission                with the 1-hour limit is expected to                  have occurred, but the third day would
                                                value.                                                  result in three exceedance days (i.e.,                not have an exceedance that otherwise
                                                   EPA recognizes that some sources                     three days with hourly values above 75                would have occurred, and the fourth
                                                have highly variable emissions, for                     ppb) and a fourth day with a maximum                  day would have been below, rather than
                                                example due to variations in fuel sulfur                hourly value at 75 ppb. By comparison,                at, 75 ppb. In this example, the fourth
                                                content and operating rate, that can                    with the source complying with a longer               highest maximum daily concentration
                                                make it extremely difficult, even with a                term limit, it is possible that additional            under the 30-day average would be 67.5
                                                well-designed control strategy, to ensure               exceedances would occur that would                    ppb.
                                                in practice that emissions for any given                not occur in the 1-hour limit scenario (if               This simplified example illustrates
                                                hour do not exceed the critical emission                emissions exceed the critical emission                the findings of a more complicated
                                                value. EPA also acknowledges the                        value at times when meteorology is                    statistical analysis that EPA conducted
                                                concern that longer term emission limits                conducive to poor air quality). However,              using a range of scenarios using actual
                                                can allow short periods with emissions                  this comparison must also factor in the               plant data. As described in Appendix B
                                                above the ‘‘critical emissions value,’’                 likelihood that exceedances that would                of EPA’s 2014 SO2 Nonattainment
                                                which, if coincident with                               be expected in the 1-hour limit scenario              Guidance, EPA found that the
                                                meteorological conditions conducive to                  would not occur in the longer term limit              requirement for lower average emissions
                                                high SO2 concentrations, could in turn                  scenario. This result arises because the              is highly likely to yield better air quality
                                                create the possibility of a NAAQS                       longer term limit requires lower                      than is required with a comparably
                                                exceedance occurring on a day when an                   emissions most of the time (because the               stringent 1-hour limit. Based on
                                                exceedance would not have occurred if                   limit is set well below the critical                  analyses described in Appendix B of its
                                                emissions were continuously controlled                  emission value), so a source complying                2014 SO2 Nonattainment Guidance, EPA
                                                at the level corresponding to the critical              with an appropriately set longer term                 expects that an emission profile with
                                                emission value. However, for several                    limit is likely to have lower emissions               maximum allowable emissions under an
                                                reasons, EPA believes that the approach                 at critical times than would be the case              appropriately set comparably stringent
                                                recommended in its guidance document                    if the source were emitting as allowed                30-day average limit is likely to have the
                                                suitably addresses this concern. First,                 with a 1-hour limit.                                  net effect of having a lower number of
                                                from a practical perspective, EPA                          As a hypothetical example to                       exceedances and better air quality than
                                                expects the actual emission profile of a                illustrate these points, suppose a source             an emission profile with maximum
                                                source subject to an appropriately set                  that always emits 1000 pounds of SO2                  allowable emissions under a 1-hour
                                                longer term average limit to be similar                 per hour, which results in air quality at             emission limit at the critical emission
                                                to the emission profile of a source                     the level of the NAAQS (i.e., results in              value. This result provides a compelling
                                                subject to an analogous 1-hour average                  a design value of 75 ppb). Suppose                    policy rationale for allowing the use of
                                                limit. EPA expects this similarity                      further that in an ‘‘average year,’’ these            a longer averaging period, in
                                                because it has recommended that the                     emissions cause the 5 highest maximum                 appropriate circumstances where the
                                                longer term average limit be set at a                   daily average 1-hour concentrations to                facts indicate this result can be expected
                                                level that is comparably stringent to the               be 100 ppb, 90 ppb, 80 ppb, 75 ppb, and               to occur.
                                                otherwise applicable 1-hour limit                       70 ppb. Then suppose that the source                     The question then becomes whether
                                                (reflecting a downward adjustment from                  becomes subject to a 30-day average                   this approach, which is likely to
                                                the critical emissions value) and that                  emission limit of 700 pounds per hour.                produce a lower number of overall
khammond on DSK30JT082PROD with PROPOSAL




                                                                                                        It is theoretically possible for a source             exceedances even though it may
                                                  4 An ‘‘average year’’ is used to mean a year with     meeting this limit to have emissions that             produce some unexpected exceedances
                                                average air quality. While 40 CFR 50 Appendix T         occasionally exceed 1000 pounds per                   above the critical emission value, meets
                                                provides for averaging three years of 99th percentile   hour, but with a typical emissions                    the requirement in section 110(a)(1) and
                                                daily maximum values (e.g., the fourth highest          profile, emissions would much more                    172(c)(1) for SIPs to ‘‘provide for
                                                maximum daily concentration in a year with 365
                                                days with valid data), this discussion and an
                                                                                                        commonly be between 600 and 800                       attainment’’ of the NAAQS. For SO2, as
                                                example below uses a single ‘‘average year’’ in order   pounds per hour. In this simplified                   for other pollutants, it is generally
                                                to simplify the illustration of relevant principles.    example, assume a zero background                     impossible to design a nonattainment


                                           VerDate Sep<11>2014   16:52 Nov 16, 2018   Jkt 247001   PO 00000   Frm 00019   Fmt 4702   Sfmt 4702   E:\FR\FM\19NOP1.SGM   19NOP1


                                                58210                Federal Register / Vol. 83, No. 223 / Monday, November 19, 2018 / Proposed Rules

                                                plan in the present that will guarantee                 require use of an emission database                   air quality dispersion modeling (See
                                                that attainment will occur in the future.               from another source. The recommended                  Appendix W to 40 CFR part 51) to show
                                                A variety of factors can cause a well-                  method involves using these data to                   that the mix of sources and enforceable
                                                designed attainment plan to fail and                    compute a complete set of emission                    control measures and emission rates in
                                                unexpectedly not result in attainment,                  averages, computed according to the                   an identified area will not lead to a
                                                for example if meteorology occurs that                  averaging time and averaging                          violation of the SO2 NAAQS. For a
                                                is more conducive to poor air quality                   procedures of the prospective emission                short-term (i.e., 1-hour) standard, EPA
                                                than was anticipated in the plan.                       limitation. In this recommended                       believes that dispersion modeling, using
                                                Therefore, in determining whether a                     method, the ratio of the 99th percentile              allowable emissions and addressing
                                                plan meets the requirement to provide                   among these long term averages to the                 stationary sources in the affected area
                                                for attainment, EPA’s task is commonly                  99th percentile of the 1-hour values                  (and in some cases those sources located
                                                to judge not whether the plan provides                  represents an adjustment factor that may              outside the nonattainment area which
                                                absolute certainty that attainment will                 be multiplied by the candidate 1-hour                 may affect attainment in the area) is
                                                in fact occur, but rather whether the                   emission limit to determine a longer                  technically appropriate, efficient and
                                                plan provides an adequate level of                      term average emission limit that may be               effective in demonstrating attainment in
                                                confidence of prospective NAAQS                         considered comparably stringent.5 The                 nonattainment areas because it takes
                                                attainment. From this perspective, in                   2014 SO2 Nonattainment Guidance also                  into consideration combinations of
                                                evaluating use of a 30-day average limit,               addresses a variety of related topics,                meteorological and emission source
                                                EPA must weigh the likely net effect on                 such as the potential utility of setting              operating conditions that may
                                                air quality. Such an evaluation must                    supplemental emission limits, such as                 contribute to peak ground-level
                                                consider the risk that occasions with                   mass-based limits, to reduce the                      concentrations of SO2.
                                                meteorology conducive to high                           likelihood and/or magnitude of elevated                  The meteorological data used in the
                                                concentrations will have elevated                       emission levels that might occur under                analysis should generally be processed
                                                emissions leading to exceedances that                   the longer term emission rate limit.                  with the most recent version of
                                                would not otherwise have occurred, and                     Preferred air quality models for use in            AERMOD Meteorological Preprocessor
                                                must also weigh the likelihood that the                 regulatory applications are described in              (AERMET). Estimated concentrations
                                                requirement for lower emissions on                      Appendix A of EPA’s Guideline on Air                  should include ambient background
                                                average will result in days not having                  Quality Models (40 CFR part 51,                       concentrations, should follow the form
                                                exceedances that would have been                        Appendix W).6 In 2005, EPA                            of the standard, and should be
                                                expected with emissions at the critical                 promulgated the American                              calculated as described in section
                                                emissions value. Additional policy                      Meteorological Society/Environmental                  2.6.1.2 of the August 23, 2010
                                                considerations, such as in this case the                Protection Regulatory Model (AERMOD)                  clarification memo on ‘‘Applicability of
                                                desirability of accommodating real                      as the Agency’s preferred near-field                  Appendix W Modeling Guidance for the
                                                world emissions variability without                     dispersion modeling for a wide range of               1-hr SO2 National Ambient Air Quality
                                                significant risk of violations, are also                regulatory applications addressing                    Standard’’ (U. S. EPA, 2010a).
                                                appropriate factors for the EPA to weigh                stationary sources (for example in
                                                                                                                                                              IV. Pennsylvania’s Attainment Plan
                                                in judging whether a plan provides a                    estimating SO2 concentrations) in all
                                                                                                                                                              Submittal for the Allegheny Area
                                                reasonable degree of confidence that the                types of terrain based on extensive
                                                                                                        developmental and performance                            In accordance with section 172(c) of
                                                plan will lead to attainment. Based on                                                                        the CAA, the Pennsylvania attainment
                                                                                                        evaluation. Supplemental guidance on
                                                these considerations, especially given                                                                        plan for the Allegheny County Area
                                                                                                        modeling for purposes of demonstrating
                                                the high likelihood that a continuously                                                                       includes: (1) An emissions inventory for
                                                                                                        attainment of the SO2 standard is
                                                enforceable limit averaged over as long                                                                       SO2 for the plan’s base year (2011); (2)
                                                                                                        provided in Appendix A to the April 23,
                                                as 30 days, determined in accordance                                                                          an attainment demonstration including
                                                                                                        2014 SO2 nonattainment area SIP
                                                with EPA’s guidance, will result in                                                                           analyses that locate, identify, and
                                                                                                        guidance document referenced above.
                                                attainment, EPA believes as a general                                                                         quantify sources of emissions
                                                                                                        Appendix A provides extensive
                                                matter that such limits, if appropriately                                                                     contributing to violations of the 2010
                                                                                                        guidance on the modeling domain, the
                                                determined, can reasonably be                                                                                 SO2 NAAQS as well as a dispersion
                                                                                                        source inputs, assorted types of
                                                considered to provide for attainment of                                                                       modeling analysis of an emissions
                                                                                                        meteorological data, and background
                                                the 2010 SO2 NAAQS.                                     concentrations. Consistency with the                  control strategy for the primary SO2
                                                   The 2014 SO2 Nonattainment                           recommendations in this guidance is                   sources (USS Clairton, Edgar Thomson
                                                Guidance offers specific                                generally necessary for the attainment                and Irvin Plants and Harsco Metals)
                                                recommendations for determining an                      demonstration to offer adequately                     showing attainment of the SO2 NAAQS
                                                appropriate longer term average limit.                  reliable assurance that the plan provides             by the October 4, 2018 attainment date;
                                                The recommended method starts with                      for attainment.                                       (3) a determination that the control
                                                determination of the 1-hour emission                       As stated previously, attainment                   strategy for the primary SO2 source
                                                limit that would provide for attainment                 demonstrations for the 2010 1-hour                    within the nonattainment areas
                                                (i.e., the critical emission value), and                primary SO2 NAAQS must demonstrate                    constitutes RACM/RACT; (4)
                                                applies an adjustment factor to                         future attainment and maintenance of                  requirements for RFP toward attaining
                                                determine the (lower) level of the longer               the NAAQS in the entire area                          the SO2 NAAQS in the Area; (5)
                                                term average emission limit that would                  designated as nonattainment (i.e., not                contingency measures; (6) the assertion
khammond on DSK30JT082PROD with PROPOSAL




                                                be estimated to have a stringency                       just at the violating monitor) by using               that Pennsylvania’s existing SIP-
                                                comparable to the otherwise necessary                                                                         approved NNSR program meets the
                                                1-hour emission limit. This method uses                   5 For example, if the critical emission value is    applicable requirements for SO2; and (7)
                                                a database of continuous emission data                  1000 pounds of SO2 per hour, and a suitable           the request that emission limitations
                                                reflecting the type of control that the                 adjustment factor is determined to be 70 percent,     and compliance parameters for Clairton,
                                                                                                        the recommended longer term average limit would
                                                source will be using to comply with the                 be 700 pounds per hour.                               Edgar Thomson and Irvin Plants and
                                                SIP emission limits, which (if                            6 The EPA published revisions to the Guideline      Harsco Metals be incorporated into the
                                                compliance requires new controls) may                   on Air Quality Models on January 17, 2017.            SIP.


                                           VerDate Sep<11>2014   16:52 Nov 16, 2018   Jkt 247001   PO 00000   Frm 00020   Fmt 4702   Sfmt 4702   E:\FR\FM\19NOP1.SGM   19NOP1


                                                                     Federal Register / Vol. 83, No. 223 / Monday, November 19, 2018 / Proposed Rules                                                           58211

                                                V. EPA’s Analysis of Pennsylvania’s                        For the base year inventory of actual                inventory that includes estimated
                                                Attainment Plan Submittal for the                       emissions, a ‘‘comprehensive, accurate                  emissions for all emission sources of
                                                Allegheny Area                                          and current’’ inventory can be                          SO2 which are determined to impact the
                                                   Consistent with CAA requirements                     represented by a year that contributed to               nonattainment area for the year in
                                                (see section 172), an attainment                        the three-year design value used for the                which the Area is expected to attain the
                                                                                                        original nonattainment designation. The                 NAAQS. Pennsylvania provided a 2018
                                                demonstration for a SO2 nonattainment
                                                                                                        2014 SO2 Nonattainment Guidance                         projected emissions inventory for all
                                                area must include a showing that the
                                                                                                        notes that the base year inventory                      known sources included in the 2011
                                                area will attain the 2010 SO2 NAAQS as
                                                                                                        should include all sources of SO2 in the                base year inventory, and EPA finds
                                                expeditiously as practicable. The
                                                                                                        nonattainment area as well as any                       Pennsylvania appropriately developed
                                                demonstration must also meet the
                                                                                                        sources located outside the                             this inventory as discussed in the
                                                requirements of 40 CFR 51.112 and 40
                                                                                                        nonattainment area which may affect                     emissions inventory TSD. The projected
                                                CFR part 51, Appendix W, and include
                                                                                                        attainment in the area. Pennsylvania                    2018 emissions are shown in Table 2.
                                                inventory data, modeling results, and
                                                                                                        appropriately elected to use 2011 as the                Pennsylvania’s submittal asserts that the
                                                emissions reductions analyses on which
                                                                                                        base year. Actual emissions from all the                SO2 emissions are expected to decrease
                                                the state has based its projected
                                                                                                        sources of SO2 in the Allegheny Area                    by approximately 618 tons, or 18%, by
                                                attainment. EPA is proposing that the                   were reviewed and compiled for the                      2018 from the 2011 base year.8 A
                                                attainment plan submitted by                            base year emissions inventory                           detailed discussion of the projected
                                                Pennsylvania is sufficient, and EPA is                  requirement. The primary SO2-emitting                   emissions for the Allegheny Area and
                                                proposing to approve the plan to ensure                 point sources located within the                        EPA’s analysis of emissions can be
                                                ongoing attainment.                                     Allegheny Area are the USS Mon Valley                   found in Pennsylvania’s October 3, 2017
                                                A. Pollutants Addressed                                 Works—Clairton, Edgar Thomson and                       submittal as well as in the emissions
                                                                                                        Irvin Plants with SO2 emissions in 2011                 inventory TSD, which can be found
                                                  Pennsylvania’s SO2 attainment plan
                                                                                                        of 1468 tons per year (tpy), 1279 tpy,                  under Docket ID No. EPA–R03–OAR–
                                                evaluates SO2 emissions for the
                                                                                                        and 419 tpy, respectively. The Harsco                   2017–0730 and online at
                                                Allegheny Area comprised of a portion
                                                                                                        Metals facility which is located on the                 www.regulations.gov.
                                                of Allegheny County that is designated                  Edgar Thomson plant property is the
                                                nonattainment for the 2010 SO2                          next largest source with 7 tpy of SO2
                                                NAAQS. There are no precursors to                                                                                  TABLE 2—2018 PROJECTED SO2
                                                                                                        emissions in 2011. A more detailed                         EMISSION INVENTORY FOR THE AL-
                                                consider for the SO2 attainment plan.                   discussion of the emissions inventory
                                                SO2 is a pollutant that arises from direct                                                                         LEGHENY AREA
                                                                                                        for the Allegheny Area and EPA’s
                                                emissions, and therefore concentrations                 analysis of the Area can be found in
                                                are highest relatively close to the                                                                                                                      SO2 emissions
                                                                                                        Pennsylvania’s October 3, 2017                          Emission source category                     (tpy)
                                                sources and much lower at greater                       submittal as well as the emissions
                                                distances due to dispersion. Thus, SO2                  inventory Technical Support Document                    Point ................................          2676.52
                                                concentration patterns resemble those of                (TSD), which can be found under                         Area ................................            119.18
                                                other directly emitted pollutants like                  Docket ID No. EPA–R03–OAR–2017–                         Non-road .........................                 0.44
                                                lead, and differ from those of                                                                                  On-road ...........................                2.96
                                                                                                        0730 and which is available online at
                                                photochemically-formed (secondary)                      www.regulations.gov.                                       Total ............................           2799.10
                                                pollutants such as ozone.                                  Table 1 shows the level of emissions,
                                                Pennsylvania’s attainment plan                          expressed in tpy, in the Allegheny Area
                                                appropriately considered SO2 emissions                                                                           C. Air Quality Modeling
                                                                                                        for the 2011 base year by emissions
                                                for the Allegheny Area.                                 source category.                                            The SO2 attainment demonstration
                                                                                                                                                                 provides an air quality dispersion
                                                B. Emissions Inventory Requirements                                                                              modeling analysis to demonstrate that
                                                                                                          TABLE 1—2011 BASE YEAR SO2
                                                   States are required under section                      EMISSIONS INVENTORY FOR THE AL- control strategies chosen to reduce SO2
                                                172(c)(3) of the CAA to develop                                                                                  source emissions will bring the Area
                                                                                                          LEGHENY AREA
                                                comprehensive, accurate and current                                                                              into attainment by the statutory
                                                emissions inventories of all sources of                                                        SO                attainment date of October 4, 2018. The
                                                                                                                                                  2 emissions
                                                the relevant pollutant or pollutants in                 Emission source category                                 modeling analysis, which the state is to
                                                                                                                                                    (tpy)
                                                the nonattainment area. These                                                                                    conduct in accordance with Appendix
                                                inventories provide detailed accounting                 Point ................................          3249.20 W to 40 CFR part 51 (EPA’s Modeling
                                                of all emissions and emissions sources                  Area ................................             158.85 Guidance), is used for the attainment
                                                by precursor or pollutant. In addition,                 Non-road .........................                  1.17 demonstration to assess the control
                                                                                                        On-road ...........................                 8.11
                                                inventories are used in air quality                                                                              strategy for a nonattainment area and
                                                modeling to demonstrate that                              Total ............................            3417.33 establish emission limits that will
                                                attainment of the NAAQS is as                                                                                    provide for attainment. In accordance
                                                expeditious as practicable. The 2014                      EPA has evaluated Pennsylvania’s                       with Appendix W, three years of
                                                SO2 Nonattainment Guidance provides                     2011 base year emissions inventory for                   prognostic meteorological data was used
                                                that the emissions inventory should be                  the Allegheny Area and has made the
                                                consistent with the Air Emissions                       determination that this inventory was                      8 Reductions in projected 2018 SO emissions in
                                                                                                                                                                                                       2
khammond on DSK30JT082PROD with PROPOSAL




                                                Reporting Requirements (AERR) at                        developed consistent with EPA’s                          the onroad, nonroad and nonpoint source categories
                                                                                                                                                                 can be attributed to lower sulfur content limits for
                                                Subpart A to 40 CFR part 51.7                           guidance. Therefore, pursuant to section gasoline and diesel fuels for the onroad and
                                                                                                        172(c)(3), EPA is proposing to approve                   nonroad sector, and more stringent sulfur content
                                                  7 The AERR at Subpart A to 40 CFR part 51 cover       Pennsylvania’s 2011 base year                            limits on home heating oil and other distillate/
                                                overarching Federal reporting requirements for the      emissions inventory for the Allegheny                    residual fuel oils for the nonpoint sector which
                                                states to submit emissions inventories for criteria                                                              limits are included in the Pennsylvania SIP.
                                                pollutants to EPA’s Emissions Inventory System.
                                                                                                        Area.                                                    Reductions in projected 2018 SO2 emissions for
                                                EPA uses these submittals, along with other data          The attainment demonstration also                      point sources are a result of the limits discussed in
                                                sources, to build the National Emissions Inventory.     provides for a projected attainment year the RACT/RACM section of this rulemaking.


                                           VerDate Sep<11>2014   16:52 Nov 16, 2018   Jkt 247001   PO 00000   Frm 00021   Fmt 4702   Sfmt 4702   E:\FR\FM\19NOP1.SGM       19NOP1


                                                58212                Federal Register / Vol. 83, No. 223 / Monday, November 19, 2018 / Proposed Rules

                                                to simulate the dispersion of pollutant                 technique, which shows significantly                  the inclusion of the BLP model within
                                                plumes from multiple point, area, or                    better model performance over the                     the AERMOD dispersion model system
                                                volume sources across the averaging                     regulatory version of AERMOD. Given                   (starting with AERMOD version 15181)
                                                times of interest. The modeling                         the high temperatures of these fugitive               using the BUOYLINE source pathway
                                                demonstration typically also relies on                  emissions, ACHD recognized that the                   keyword. ACHD began its SIP modeling
                                                maximum allowable emissions from                        plume rise and initial plume                          development for the Area using
                                                sources in the nonattainment area.                      characteristics vary by hour reflecting               AERMOD version 15181 then switched
                                                Though the actual emissions are likely                  hourly variations in meteorology in a                 to version 1616r for its final modeling
                                                to be below the allowable emissions,                    manner that is not addressed in simple                demonstration, which was the current
                                                sources have the ability to run at higher               treatments of volume sources in                       regulatory version at the time of
                                                production rates or optimize controls                   AERMOD. Therefore, ACHD used an                       submittal. Use of an alternative model
                                                such that emissions approach the                        alternate method, using EPA’s Buoyant                 needs to be approved under section 3.2
                                                allowable emissions limits. An                          Line and Point Source Model (BLP), to                 of Appendix W—Guideline on Air
                                                attainment plan must provide for                        determine hourly values of these                      Quality Models—with concurrence from
                                                attainment under all allowable scenarios                parameters. Since AERMOD does not                     EPA’s Model Clearinghouse.
                                                of operation for each source based on                   provide for volume sources to have heat                  A demonstration in support of the use
                                                the maximum allowable emissions.                        flux or otherwise to have plume rise,                 of the BLP/AERMOD Hybrid approach
                                                   ACHD provided an analysis which                      ACHD used hourly release heights                      for source characterization of the coke
                                                was developed in accordance with                        reflecting the plume height for each                  oven fugitive emissions for PM10 was
                                                EPA’s Modeling Guidance and the 2014                    hour’s meteorology estimated by the                   undertaken by ACHD as part of its 2012
                                                SO2 Nonattainment Guidance, and was                     BLP Plume Rise module. Similarly,                     Annual Fine Particle Matter (particulate
                                                prepared using the EPA dispersion                       ACHD used hourly values which                         matter less than 2.5 microns in
                                                modeling system, AERMOD. This                           characterize the initial width and height             diameter, PM2.5) attainment plan
                                                modeling demonstration also utilized                    of the release based on hourly plume                  preparation. While the demonstration
                                                the Weather Research and Forecasting                    dimensions determined by BLP.                         was used to support this approach with
                                                (WRF) model to generate prognostic                      Fugitive emissions were then included                 PM10 (simulating dispersion of primary
                                                meteorological data. EPA’s Mesoscale                    in AERMOD for each of the multiple                    particulate matter), in AERMOD both
                                                Model Interface Program (MMIF) was                      volume sources used to represent the                  PM10 and SO2 are treated as inert
                                                used to extract the prognostic                          coke batteries in the Area by using                   pollutants, therefore, they would have
                                                meteorological data which was                           volume sources with hourly release                    similar dispersion characteristics and
                                                processed using AERMET, a pre-                          heights and initial dispersion                        are directly scalable and comparable.
                                                processor to AERMOD, in accordance                      coefficients determined in this manner,               Thus, EPA finds that this approach is
                                                with 40 CFR part 51. EPA notes that our                 as contained in an hourly emission rate               applicable for all primary pollutants
                                                most recent version of 40 CFR part 51                   file. This alternative method is referred             including SO2. ACHD prepared the
                                                Appendix W allows for prognostic                        to as the BLP/AERMOD Hybrid                           analysis and submitted an alternative
                                                meteorological data to be used in                       approach.                                             modeling request under section 3.2.2
                                                AERMOD. The prognostic                                     As noted in ACHD’s modeling                        (b)(2) and (d) of Appendix W to EPA
                                                meteorological data was extracted and                   protocol document (See Appendix A of                  Region 3’s Regional Administrator on
                                                processed following the methodology                     Pennsylvania’s October 3, 2017                        July 27, 2018. EPA staff have reviewed
                                                outlined in EPA’s updated Appendix W                    submittal), the procedure for handling                ACHD’s analysis and found that the
                                                and other applicable guidance. In the                   USS’s coke oven fugitive emissions in                 BLP/AERMOD Hybrid approach
                                                particular circumstances in this Area, in               the dispersion modeling analysis was                  provides better model performance of
                                                which local topographical influences                    initially developed and used for                      the impacts from the coke oven fugitive
                                                are likely to be channeling flows in a                  previous particulate matter smaller than              emissions than the regulatory
                                                manner prone to yield different flows                   10 microns in diameter (PM10) SIP work                BUOYLINE source methodology in
                                                for different facilities in the Area, EPA               completed by ACHD and discussed in                    AERMOD. This result is consistent with
                                                believes that the prognostic                            EPA Model Clearinghouse 9 Memos                       the dispersion model performance
                                                meteorological data generated by ACHD                   from 1991 through 1994 (91–III–12, 93–                analyses ACHD described in Appendix
                                                are likely to provide a better                          III–06, and 94–III–02). (See Modeling                 A–2 Modeling Protocol Addendum, G
                                                characterization of winds in this Area                  Protocol Addendum to Appendix A of                    and I of Pennsylvania’s October 3, 2017
                                                than application of a single hourly wind                Pennsylvania’s October 3, 2017                        submittal.
                                                speed and direction across the Area.                    submittal for more information on prior                  EPA’s review and approval of ACHD’s
                                                EPA also conducted its own land use                     Model Clearinghouse memos). The                       analysis supporting the use of the BLP/
                                                survey (using the methods of Auer),                     original algorithms were developed for                AERMOD Hybrid approach followed the
                                                finding that about 70 percent (%) of the                the ACHD PM10 SIP workgroup in 1994                   EPA Model Clearinghouse concurrence
                                                Area within an area out to three                        and are currently being used by ACHD                  process as prescribed in section 3.2 of
                                                kilometers from the main sources in the                 with additional revisions to the BLP                  Appendix W. Following receipt of
                                                Area may be considered rural land use,                  Plume Rise program. This method is                    ACHD’s analysis on July 27, 2018, EPA
                                                which supports ACHD’s use of rural                      considered an alternative model due to                Region 3 recommended approval of this
                                                dispersion coefficients in its modeling                                                                       alternative modeling approach to the
                                                analysis. Further discussion of ACHD’s                    9 EPA Model Clearinghouse is the central point of   EPA Model Clearinghouse on August 7,
khammond on DSK30JT082PROD with PROPOSAL




                                                development of these meteorological                     consultation and coordination within the EPA for      2018. The EPA Model Clearinghouse
                                                                                                        reviewing the use of air quality models and
                                                data and EPA’s land use survey can be                   analytical techniques for demonstrating compliance
                                                                                                                                                              concurred with Region 3’s
                                                found in EPA’s modeling TSD, which                      or attainment with the NAAQS in regulatory            recommended approval on August 10,
                                                can be found under Docket ID No. EPA–                   applications or implementation plans. All case-       2018. EPA Region 3 then approved the
                                                R03–OAR–2017–0730.                                      specific approvals of alternative models by an EPA    use of this alternative model by letter
                                                                                                        Regional Office require consultation and
                                                   ACHD characterized USS’s Clairton                    concurrence by the Model Clearinghouse, per
                                                                                                                                                              from its Regional Administrator to
                                                Coke Works fugitive coke oven                           Section 3.2.2 of the Guideline on Air Quality         ACHD dated August 16, 2018. EPA is
                                                emissions using an alternative modeling                 Models (40 CFR part 51 Appendix W).                   providing notice in this rulemaking


                                           VerDate Sep<11>2014   16:52 Nov 16, 2018   Jkt 247001   PO 00000   Frm 00022   Fmt 4702   Sfmt 4702   E:\FR\FM\19NOP1.SGM   19NOP1


                                                                     Federal Register / Vol. 83, No. 223 / Monday, November 19, 2018 / Proposed Rules                                           58213

                                                proposal that an alternative modeling                   D. RACM/RACT                                          rich gases back into the by-products
                                                approach using the BLP/AERMOD                              CAA section 172(c)(1) requires that                facility at Clairton during planned and
                                                Hybrid approach to simulate the fugitive                each attainment plan provide for the                  unplanned outages and will be
                                                coke oven battery emissions was used                    implementation of all reasonably                      completed on or before October 4, 2018
                                                for ACHD’s SO2 attainment plan and                      available control measures (i.e., RACM)               as required by permit.
                                                that its use was approved by EPA.                                                                                In its modeling analysis, ACHD
                                                                                                        as expeditiously as practicable and shall
                                                ACHD’s request to use this alternative                                                                        determined critical emission values
                                                                                                        provide for attainment of the NAAQS.
                                                modeling approach, EPA Region 3’s                                                                             (CEV) with an hourly average for SO2
                                                                                                        EPA interprets RACM, including RACT,
                                                analysis of ACHD’s request, and the                                                                           sources. However, based on the
                                                                                                        under section 172, as measures that a
                                                EPA Model Clearinghouse concurrence                                                                           variability in sulfur content of the COG,
                                                                                                        state determines to be both reasonably
                                                is included in the docket for this                                                                            ACHD determined that several sources
                                                                                                        available and contribute to attainment
                                                rulemaking action and can be found                                                                            warrant a limit with a longer-term
                                                                                                        as expeditiously as practicable ‘‘for
                                                under Docket ID No. EPA–R03–OAR–                                                                              averaging period. As discussed
                                                                                                        existing sources in the area.’’ In
                                                2017–0730 and online at                                                                                       previously, EPA believes that
                                                                                                        addition, CAA section 172(c)(6) requires
                                                www.regulations.gov. EPA is taking                                                                            establishment of emission rate limits
                                                                                                        plans to include enforceable emission
                                                public comment on proposing to                                                                                with averaging periods longer than one
                                                                                                        limitations and control measures as may               hour may reasonably be found to
                                                approve the SIP based on the approved                   be necessary or appropriate to provide
                                                use of ACHD’s alternative modeling                                                                            provide for attainment if specified
                                                                                                        for attainment by the attainment date.                criteria recommended in EPA’s 2014
                                                approach.                                                  Pennsylvania’s October 3, 2017
                                                                                                                                                              SO2 Nonattainment Guidance are met.
                                                   The primary SO2 sources included in                  submittal discusses facility-specific                    The objective of ACHD’s analysis of
                                                the SIP modeling demonstration are the                  control measures, namely SO2 emission                 the variability of COG sulfur content is
                                                Harsco Metals facility and the three USS                limits for Harsco Metals and for the USS              to determine the adjustment factor that
                                                Mon Valley Works facilities—Clairton,                   Mon Valley Works facilities—Clairton,                 can be multiplied times the modeled
                                                Edgar Thomson and Irvin Plants. The                     Edgar Thomson and Irvin Plants, that                  CEVs to compute longer term limits that
                                                modeling properly characterized source                  were developed through the air                        will require a comparable degree of
                                                limits, local meteorological data,                      dispersion modeling submitted by                      control as would be required by 1-hour
                                                background concentrations, and                          ACHD. The modeling analysis is                        limits at the CEVs. EPA’s 2014 SO2
                                                provided an adequate model receptor                     discussed in section IV.C. Air Quality                Nonattainment Guidance states that
                                                grid to capture maximum modeled                         Modeling of this proposed rulemaking                  ‘‘. . . air agencies may determine that
                                                concentrations. Using the EPA                           and in the Modeling TSD. ACHD asserts                 an area could attain through a control
                                                conversion factor for the SO2 NAAQS,                    that the combination of controls and the              strategy that will not significantly
                                                the final modeled design value for the                  resulting emission limits at the three                change the emission distribution (as
                                                Allegheny Area (196.17 microgram per                    USS facilities and Harsco Metals is                   may be true, for example, for a strategy
                                                meter cubed, mg/m3), is less than 75                    sufficient for the Allegheny Area to                  involving a switch to lower sulfur coal
                                                ppb.10 EPA has reviewed the modeling                    meet the SO2 NAAQS and serve as                       with similar sulfur content variability or
                                                that Pennsylvania submitted to support                  RACT/RACM.                                            for a strategy involving enhancement of
                                                                                                           Controls at the Clairton and Edgar                 existing control equipment). Where the
                                                the attainment demonstration for the
                                                                                                        Thomson plants represent the majority                 control strategy does not significantly
                                                Allegheny Area and has determined that
                                                                                                        of SO2 reductions within the Allegheny                change the distribution, the source’s
                                                the modeling is consistent with CAA
                                                                                                        Area. As noted by ACHD, the Clairton                  current emission distribution may be
                                                requirements, Appendix W, and EPA’s
                                                                                                        Plant is the largest coke plant in North              the best indicator of the source’s post-
                                                guidance for SO2 attainment
                                                                                                        America. The Clairton Plant operates 10               control emission distribution.’’ In this
                                                demonstration modeling as discussed
                                                                                                        coke batteries and produces                           case, the upgrades to the VCU unit at
                                                above. Therefore, EPA is proposing to
                                                                                                        approximately 13,000 tons of coke per                 the USS Clairton plant reduce the H2S
                                                determine that the analysis
                                                                                                        day along with approximately 225                      content in the COG but are unlikely to
                                                demonstrates that the source limits used
                                                                                                        million cubic feet of coke oven gas                   cause significant changes in the
                                                in the modeling demonstration show
                                                                                                        (COG). The COG is used as fuel at all of              distribution of emissions, except to the
                                                attainment with the 1-hour SO2
                                                                                                        the Mon Valley Works facilities. At the               extent that installation of redundant
                                                NAAQS. EPA’s analysis of the modeling
                                                                                                        Clairton Plant, ACHD explained in its                 sulfur capture systems is likely to
                                                is discussed in more detail in EPA’s
                                                                                                        attainment plan that upgrades to the 100              reduce the frequency and magnitudes of
                                                modeling TSD, which can be found
                                                                                                        and 600 Vacuum Carbonate Units                        emission spikes from the facilities
                                                under Docket ID No. EPA–R03–OAR–
                                                                                                        (VCUs) will reduce the content of                     burning this COG. ACHD used the most
                                                2017–0730 and online at
                                                                                                        hydrogen sulfide (H2S) in the downriver               recent three years of operating data
                                                www.regulations.gov for this
                                                                                                        COG utilized at all Mon Valley Works                  (2014–2016) available at the time of its
                                                rulemaking. EPA proposes to conclude
                                                                                                        plants. The 100 VCU upgrade was                       analysis to analyze the variability in H2S
                                                that the modeling provided in the
                                                                                                        completed in 2016 and the 600 VCU                     content in the COG for the four primary
                                                attainment plan shows that the
                                                                                                        upgrade will add redundant controls for               COG process streams used to deliver
                                                Allegheny Area will attain the 2010
                                                                                                        the downriver COG line. Full operation                fuel to the USS Mon Valley Works
                                                1-hour primary SO2 NAAQS by the
                                                                                                        of both upgraded units will be                        plants (Unit 1, Unit 2, A Line and B
                                                attainment date.
                                                                                                        completed on or before October 4, 2018                Line). All COG is produced and
khammond on DSK30JT082PROD with PROPOSAL




                                                   10 The SO NAAQS level is expressed in ppb, but
                                                                                                        as required by permit. Source                         desulfurized at the Clairton plant and
                                                            2
                                                AERMOD gives results in micro grams per cubic
                                                                                                        monitoring to demonstrate continuous                  then distributed via pipeline to the
                                                meter (mg/m3). The conversion factor for SO2 (at the    efficient operation of the Clairton VCU               other two plants. USS upgraded its COG
                                                standard conditions applied in the ambient SO2          system is also required to be complete                sulfur removal systems in April 2016,
                                                reference method) is 1 ppb = approximately 2.619        by October 4, 2018. In addition, a tail               therefore ACHD separately analyzed the
                                                mg/m3. See Pennsylvania’s SO2 Round 3
                                                Designations proposed TSD at https://www.epa.gov/
                                                                                                        gas recycling project at the Shell Claus              8 months of data post-control to
                                                sites/production/files/2017-08/documents/35_pa_         off-gas Treatment (SCOT) plant within                 compare whether the distribution of
                                                so2_rd3-final.pdf.                                      the Clairton plant will reroute sulfur-               hydrogen sulfide (H2S) content would


                                           VerDate Sep<11>2014   16:52 Nov 16, 2018   Jkt 247001   PO 00000   Frm 00023   Fmt 4702   Sfmt 4702   E:\FR\FM\19NOP1.SGM   19NOP1


                                                58214                       Federal Register / Vol. 83, No. 223 / Monday, November 19, 2018 / Proposed Rules

                                                be similar before and after controls.                                 reasonable approximation of the degree                      order to limit the frequency and
                                                After extrapolating the post-control                                  of adjustment needed to determine the                       magnitude of occurrences of elevated
                                                data, the distribution of H2S content is                              longer term limits that are comparably                      emissions. Adjustment factors for 24-
                                                similar to the distribution before                                    stringent to the 1-hour limits that would                   hour SO2 emission limits were
                                                controls thus, ACHD concluded that the                                otherwise be established.                                   calculated for each line and applied to
                                                use of the full 3 years of data is                                       In accordance with the methods EPA                       the modeled CEV to determine the
                                                representative of overall variability and,                            recommended in Appendix C to its 2014                       emission limit with a 24-hour averaging
                                                that these upgrades are not expected to                               SO2 Nonattainment Guidance,                                 period. The 24-hour average SO2
                                                have a significant effect on variability or                           adjustment factors were determined                          emission limit adjustment factors for
                                                on the degree of adjustment to yield a                                from the variability in sulfur content in                   emission units burning COG are 0.914
                                                comparably stringent longer term                                      each line and were applied to the                           for Unit 1 Line COG, 0.898 for Unit 2
                                                average limit. Analyzing variability of                               modeled CEV for the processes using                         Line COG, 0.927 for A Line COG, and
                                                fuel quality is not a direct means of                                 that COG to determine an appropriate                        0.944 for B Line COG.
                                                analyzing the variability of emissions                                emission limit with a 30-day averaging
                                                (which also factors in the variability of                             period that is of comparable stringency                       Table 3 shows the modeled CEV, the
                                                the quantity of fuel burned). On the                                  to the 1-hour CEV. The 30-day average                       30-day and 24-hour average adjustment
                                                other hand, the facilities at issue here                              SO2 emission limit adjustment factor is                     factors and the resulting comparable 30-
                                                have relatively stable operations, and a                              0.717 for emission units burning COG                        day and 24-hour average SO2 emission
                                                complete analysis would also factor in                                from Unit 1 Line, 0.797 for units                           rate, calculated by applying the
                                                the degree to which the installation of                               burning COG from Unit 2 Line, 0.848 for                     adjustment factor to the critical
                                                redundant control systems reduces                                     units burning COG from A Line, and                          emissions value, for units affected by
                                                emission spikes and thereby reduces                                   0.834 for units burning COG from B                          COG sulfur reduction projects and units
                                                variability. For these reasons, EPA                                   Line. As recommended in 2014 SO2                            partially affected by the COG controls in
                                                believes that ACHD’s analysis should                                  Nonattainment Guidance, ACHD                                combination with other fuels at the
                                                provide a reasonable approximation of                                 determined that for sources with a 30-                      Clairton plant. Table 3 also shows new
                                                the prospective variability of emissions                              day averaging period a supplementary                        SO2 limits for units taking reductions to
                                                following implementation of the                                       24-hour limit not to be exceeded for 3                      their allowable limits at the Clairton
                                                controls in the attainment plan and a                                 consecutive days should be applied in                       plant.

                                                                                                      TABLE 3—SO2 EMISSION LIMITS FOR USS CLAIRTON PLANT
                                                                                                                                        Adjustment                                                  Adjustment
                                                                                                                                                               New emission                                        Supplemental
                                                                                                                      CEV                  factor                                 Averaging             factor
                                                                        Process                                                                                    limit                                           24-hour limit
                                                                                                                    (lbs/hr)            (for 30-day                                period           (for 24-hour
                                                                                                                                                                 (lbs/hr)                                             (lbs/hr)
                                                                                                                                            limit)                                                       limit)

                                                Boiler 1 .....................................................           142.01                   0.834               118.44           30-day              0.944          134.06
                                                                                                                     (aggregate
                                                                                                                       basis) 11
                                                Boiler 2.
                                                Boiler R1.
                                                Boiler R2.
                                                Boiler T1.
                                                Boiler T2.
                                                Battery 1 Underfiring ................................                      14.52                  0.717               10.41           30-day              0.914           13.27
                                                Battery 2 Underfiring ................................                      12.76                  0.717                9.15           30-day              0.914           11.66
                                                Battery 3 Underfiring ................................                      14.74                  0.717               10.57           30-day              0.914           13.47
                                                Battery 13 Underfiring ..............................                       17.48                  0.797               13.93           30-day              0.898           15.70
                                                Battery 14 Underfiring ..............................                       17.60                  0.797               14.03           30-day              0.898           15.80
                                                Battery 15 Underfiring ..............................                       23.43                  0.797               18.67           30-day              0.898           21.04
                                                Battery 19 Underfiring ..............................                       36.85                  0.797              229.37           30-day              0.898           33.09
                                                Battery 20 Underfiring ..............................                       33.88                  0.797               27.00           30-day              0.898           30.42
                                                B Battery Underfiring ...............................                       29.82                  0.717               21.38           30-day              0.914           27.26
                                                C Battery Underfiring ...............................                       44.67                  0.717               32.03           30-day              0.914           40.83
                                                SCOT Incinerator .....................................                         24   ........................              24           1-hour
                                                PEC Baghouse 1–3 .................................                           7.10   ........................            7.10           1-hour
                                                PEC Baghouse 13–15 .............................                             7.46   ........................            7.46           1-hour
                                                PEC Baghouse 19–20 .............................                             7.78   ........................            7.78           1-hour
                                                PEC Baghouse B .....................................                         7.50   ........................            7.50           1-hour
                                                PEC Baghouse C .....................................                         8.65   ........................            8.65           1-hour
                                                Quench Tower 1 ......................................                        0.75   ........................            0.75           1-hour
                                                Quench Tower B ......................................                        4.09   ........................            4.09           1-hour
                                                Quench Tower C ......................................                        5.00   ........................            5.00           1-hour
                                                Quench Tower 5A ....................................                         7.56   ........................            7.56           1-hour
khammond on DSK30JT082PROD with PROPOSAL




                                                Quench Tower 7A ....................................                         7.21   ........................            7.21           1-hour
                                                Batteries 1–3 Hot Car ..............................                        10.64   ........................           10.64           1-hour
                                                Batteries 13–15 Hot Car ..........................                          11.21   ........................           11.21           1-hour
                                                Batteries 19–20 Hot Car ..........................                          13.73   ........................           13.73           1-hour
                                                C Battery Hot Car ....................................                       5.82   ........................            5.82           1-hour
                                                   11 ACHD ran 16 different modeling scenarios for the various boiler stacks at the Clairton plant and used the worst case boiler impacts in its
                                                final analysis. Additional information can be found in ACHD’s SIP submittal’s Appendix I included in the docket for this rulemaking and is avail-
                                                able online at www.regulations.gov.



                                           VerDate Sep<11>2014        16:52 Nov 16, 2018         Jkt 247001      PO 00000   Frm 00024    Fmt 4702        Sfmt 4702   E:\FR\FM\19NOP1.SGM   19NOP1


                                                                         Federal Register / Vol. 83, No. 223 / Monday, November 19, 2018 / Proposed Rules                                                   58215

                                                   EPA’s guidance advises that, to help                     details regarding ACHD’s longer term                   suitable 1-hour limit, especially when
                                                assure attainment near sources with                         limits and variability analysis can be                 accompanied by supplemental limits
                                                longer term limits, states should assure                    found in Appendix D of Pennsylvania’s                  that help minimize the frequency and
                                                that occasions with hourly emissions                        October 3, 2017 submittal which can be                 magnitude of spikes in emissions, can
                                                above the CEV are limited in frequency                      found under Docket ID No. EPA–R03–                     be found to provide for attainment of
                                                and magnitude. The supplemental                             OAR–2017–0730 and online at                            the 2010 SO2 NAAQS. In evaluating
                                                limits that ACHD has adopted,                               www.regulations.gov.                                   these longer term averaging times, EPA
                                                providing 24-hour average limits to                            For these sources with limits based on              proposes to find that the emission limits
                                                supplement the 30-day average limits,                       longer averaging periods, H2S content                  with these longer term averaging times
                                                serve this purpose. To evaluate these                       will be measured by a continuous                       were appropriately set in accordance
                                                limits, ACHD analyzed SO2 emissions                         source monitoring device and flow                      with EPA’s 2014 SO2 Nonattainment
                                                from one source at the Clairton facility                    meter equipment that measures the                      Guidance and are sufficient for the
                                                (Battery 20 underfiring) at maximum                         actual hourly flow of gas. SO2 emissions               Allegheny Area to attain the 2010 SO2
                                                                                                            will then be calculated by assuming                    NAAQS.
                                                flow rate and compared hourly emission
                                                                                                            complete conversion of the combusted
                                                values to the 30-day, 24-hour and CEV                                                                                 The USS Edgar Thomson plant is an
                                                                                                            H2S. The SO2 values will be calculated
                                                limits. ACHD’s analysis indicates that,                                                                            iron and steel making facility which
                                                                                                            hourly, averaged over a 24-hour basis
                                                for this unit, over a two month span the                                                                           mainly produces steel slabs. At the USS
                                                                                                            (calendar day) and then averaged over a
                                                30-day limit and 24-hour limits were                                                                               Edgar Thomson facility, a new stack and
                                                                                                            rolling 30-day basis. All sources
                                                not exceeded while the CEV was                                                                                     a combined flue system is planned for
                                                                                                            utilizing a 30-day rolling average also
                                                exceeded four times. Actual flow rate                                                                              Riley Boilers 1, 2 and 3. All boilers will
                                                                                                            have an additional shorter term 24-hour
                                                for the months analyzed was 70% of the                      limit which may not be exceeded more                   exhaust to the new stack which is below
                                                maximum flowrate in which the CEV                           than three consecutive days. A more                    good engineering practice (GEP) stack
                                                would have been exceeded twice by less                      detailed discussion of ACHD’s statistical              height. Specifically, the height of this
                                                than 2 lb/hr in the time period. In                         analysis that was used to develop the                  stack, 85 meters, is lower than the
                                                addition, ACHD evaluated the hours                          proposed 30-day average limits and                     formula GEP height based on the
                                                which were above the CEV at either                          supplemental 24-hour limits for the                    dimensions of nearby buildings, 97
                                                flowrate and the Liberty monitor values                     Allegheny Area can be found in                         meters.
                                                ranged from 0–13 ppb at those times                         Appendix D of Pennsylvania’s October                      Actual emissions will be reduced as a
                                                and meteorology was typical for the                         3, 2017 submittal found under Docket                   result of the boilers using the lower H2S
                                                months. EPA does not have the                               ID No. EPA–R03–OAR–2017–0730.                          content COG from the USS Clairton
                                                emissions data to make quantitative                         Additionally, EPA’s 2014 SO2                           plant in combination with other fuels,
                                                estimates of the expected frequency or                      Nonattainment Guidance and section I.                  and thus emissions for the boilers will
                                                magnitude of emissions exceeding the                        of this proposed rulemaking provide an                 be reduced on an aggregate basis. New
                                                CEVs, but EPA believes, particularly                        extensive discussion of EPA’s rationale                emission limits for the boilers at the
                                                with the application of the 24-hour                         for concluding that emission limits                    Edgar Thomson plant are listed in Table
                                                supplemental limits, that these                             based on averaging times as long as 30                 4 along with other sources with reduced
                                                occasions are likely to be modest in                        days that are appropriately set,                       SO2 allowable limits; all of these limits
                                                frequency and magnitude. Further                            reflecting comparable stringency to a                  are established on a 1-hour basis.12

                                                                                          TABLE 4—SO2 EMISSION LIMITS FOR USS EDGAR THOMSON PLANT
                                                       Process                                                                     New * Emission Limit (lbs/hr)

                                                                                                                              Combustion Units

                                                Boiler 1 .................                                                                                                                556.91 (aggregate basis)
                                                Boiler 2.
                                                Boiler 3.
                                                Blast Furnace 1
                                                  Stoves ..............                                                                                                                                        98.50
                                                Blast Furnace 3
                                                  Stoves ..............                                                                                                                                        90.00

                                                                                                                        Non-Combustion Units

                                                Blast Furnace 1
                                                  Casthouse
                                                  (Roof + Fume) ..                                                                                                                                               2.01
                                                Blast Furnace 3
                                                  Casthouse
                                                  (Roof + Fume) ..                                                                                                                                               1.69
                                                BOP Process
khammond on DSK30JT082PROD with PROPOSAL




                                                  (Roof) ...............                                                                                                                                         6.64

                                                   12 Subsequent to ACHD’s submittal of its                 sections C and D of this rulemaking. However,          with the same SO2 emission limitations in the
                                                attainment plan for the Area, ACHD informed EPA             ACHD has confirmed to EPA (by email) that              modeling submitted with ACHD’s attainment plan
                                                that the new stack at the Edgar Thompson plant              subsequent modeling with the new stack                 for the Area. A copy of this email dated December
                                                might have different parameters than the ‘‘new              parameters (e.g. location, height, temperature,        8, 2017 with technical documentation supporting
                                                stack’’ parameters included in the attainment plan’s        velocity) at the Edgar Thomson plant is consistent     ACHD’s conclusion is included in the docket for
                                                attainment demonstration modeling. The stack is             with the submitted modeling demonstration              this rulemaking and is available online at
                                                part of the modeled control strategy discussed in           showing SO2 attainment by the attainment date          www.regulations.gov.



                                           VerDate Sep<11>2014       16:52 Nov 16, 2018   Jkt 247001   PO 00000   Frm 00025    Fmt 4702   Sfmt 4702   E:\FR\FM\19NOP1.SGM   19NOP1


                                                58216                      Federal Register / Vol. 83, No. 223 / Monday, November 19, 2018 / Proposed Rules

                                                                                   TABLE 4—SO2 EMISSION LIMITS FOR USS EDGAR THOMSON PLANT—Continued
                                                       Process                                                                                 New * Emission Limit (lbs/hr)

                                                Continuous Cast-
                                                  ing (Roof) .........                                                                                                                                                                     5.25
                                                Casthouse
                                                  Baghouse .........                                                                                                                                                                    45.10
                                                   * New emission limit is equivalent to modeled CEV for Edgar Thomson sources.


                                                   The USS Irvin plant is a secondary                                Irvin plant are mainly a result of the                      units at the Irvin plant receive COG via
                                                steel processing plant which receives                                COG controls reducing the sulfur                            the B Line. Emission limits for units at
                                                steel slabs and performs one of several                              content in the COG. The 80-inch Hot                         the USS Irvin plant are listed in Table
                                                finishing processes on the steel slabs.                              Strip Mill receives COG via the A Line                      5.
                                                Reductions in SO2 emissions at the USS                               from the Clairton plant while all other

                                                                                                    TABLE 5—SO2 EMISSION LIMITS FOR U.S. STEEL IRVIN PLANT
                                                                                                                                       Adjustment                                                  Adjustment
                                                                                                                                                              New emission                                                Supplemental
                                                                                                                     CEV                  factor                                 Averaging             factor
                                                                        Process                                                                                   limit                                                   24-hour limit
                                                                                                                   (lbs/hr)            (for 30-day                                period           (for 24-hour
                                                                                                                                                                (lbs/hr)                                                     (lbs/hr)
                                                                                                                                           limit)                                                       limit)

                                                Boiler #1 ...................................................               9.45                 0.834                  7.88          30 day                 0.944                        8.92
                                                Boiler #2 ...................................................              10.02                 0.834                  8.36          30 day                 0.944                        9.46
                                                Boiler #3–4
                                                (aggregate) ...............................................                 9.85                 0.834                  8.21          30 day                 0.944                        9.30
                                                80″ Hot Strip Reheat
                                                (aggregate) ...............................................            128.10                     0.848              108.63           30 day                 0.927                    118.75
                                                HPH Annealing Furnaces
                                                (aggregate) ...............................................                14.39                 0.834                    12          30 day                 0.944                      13.58
                                                Open Coil Annealing
                                                (aggregate) ...............................................                13.79                  0.834                 11.5          30 day                  0.944                      13.02
                                                Continuous Annealing ..............................                         9.68                  0.834                 8.07          30 day                  0.944                        9.14
                                                #1 Galvanizing Line .................................                       0.04   ........................             0.04          1-hour   ........................   ........................
                                                #2 Galvanizing Line .................................                       0.01   ........................             0.01          1-hour   ........................   ........................



                                                   In addition, Harsco Metals (also                                  which feed the Edgar Thompson and                           provided for comparable stringency by
                                                known as Braddock Recovery Inc) is                                   Irvin facilities; record-keeping,                           computing adjustment factors in
                                                located on the property of the USS                                   reporting, and stack testing                                accordance with the method that EPA
                                                Edgar Thomson plant. Harsco uses a                                   requirements at all facilities. ACHD                        recommended in Appendix C of its
                                                rotary kiln fired with COG which is                                  affirms that the implementation of new                      guidance and adopting longer term
                                                supplied by USS Clairton plant. As a                                 emission limits and corresponding                           average limits (where applicable) that
                                                result of the lower sulfur content in the                            compliance parameters at the three USS                      are adjusted accordingly. Also in
                                                USS-produced COG, Harsco has become                                  Mon Valley Works facilities and Harsco                      accordance with EPA’s
                                                subject to a lower SO2 limit of 1.8 lbs/                             Metals will enable the Allegheny Area                       recommendations, ACHD has
                                                hr as a 1-hour average for the rotary                                to attain and maintain the SO2 NAAQS.                       established supplemental limits that
                                                kiln.                                                                The AERMOD modeling analysis shows,                         will help assure that occasions of
                                                   Emission limits at all four facilities                            as discussed in detail in the Modeling                      emissions above the critical 1-hour
                                                (USS Clairton, Edgar Thomson and Irvin                               TSD, that the emission limits listed in                     emission rate will be limited in
                                                Plants and Harsco Metals) were                                       Tables 3, 4 and 5 and the limit for                         frequency and magnitude. Therefore,
                                                established through enforceable                                      Harsco Metals (modeling the 1-hour                          EPA believes that ACHD has met EPA’s
                                                installation permits (See Appendices K                               limits where applicable and modeling                        recommended criteria for longer term
                                                of Pennsylvania’s October 3, 2017 SIP                                the 1-hour equivalents where longer                         average limits to be part of a plan that
                                                submittal). The collective emission                                  term average limits apply) are sufficient                   provides suitable assurances that the
                                                limits and related compliance                                        for the Allegheny Area to attain the 1-                     area will attain the standard.
                                                parameters (i.e., testing, monitoring,                               hour SO2 NAAQS.                                                ACHD also evaluated potential RACT
                                                record keeping and reporting) have been                                 EPA’s guidance for longer term                           at other sources in the Allegheny Area
                                                proposed for incorporation into the SIP                              average limits is that plans based on                       including Koppers Inc.—Clairton Plant,
                                                as part of the attainment plan in                                    such limits can be considered to provide                    Clairton Slag—West Elizabeth Plant,
khammond on DSK30JT082PROD with PROPOSAL




                                                accordance with CAA section 172. The                                 for attainment where appropriate as                         Eastman Chemical Resins Inc.—
                                                emission limits for each of the SO2-                                 long as the longer term limit is                            Jefferson Plant and Kelly Run
                                                emitting USS Mon Valley facilities are                               comparably stringent to the 1-hour limit                    Sanitation—Forward Township. All
                                                listed in Tables 3, 4 and 5. The                                     that would otherwise be set and EPA                         sources have less than 5 tpy of
                                                compliance parameters include                                        can have reasonable confidence that                         allowable SO2 emissions. ACHD
                                                continuous process monitoring of H2S                                 occasions of emissions above the critical                   determined that no additional controls
                                                content and flow rate of the COG at                                  1-hour emission rate will be limited in                     would be technically or economically
                                                Clairton facility and the four lines                                 frequency and magnitude. ACHD has                           feasible for the purposes of SO2 RACT


                                           VerDate Sep<11>2014        16:52 Nov 16, 2018        Jkt 247001      PO 00000   Frm 00026    Fmt 4702        Sfmt 4702   E:\FR\FM\19NOP1.SGM   19NOP1


                                                                     Federal Register / Vol. 83, No. 223 / Monday, November 19, 2018 / Proposed Rules                                           58217

                                                at these small sources. ACHD also noted                 and repeated in the 2014 SO2                          SO2 presents special considerations. As
                                                that Guardian Industries permanently                    Nonattainment Guidance, EPA                           stated in the final 2010 SO2 NAAQS
                                                shut down in 2015; therefore, no RACT                   continues to believe that this definition             promulgation on June 22, 2010 (75 FR
                                                analysis was performed for Guardian                     is most appropriate for pollutants that               35520) and in the 2014 SO2
                                                Industries. In addition, ACHD examined                  are emitted from numerous and diverse                 Nonattainment Guidance, EPA
                                                several RACM options for area, nonroad                  sources, where the relationship between               concluded that because of the
                                                and mobile sources of SO2 in the Area                   particular sources and ambient air                    quantifiable relationship between SO2
                                                and determined no additional controls                   quality are not directly quantified. In               sources and control measures, it is
                                                are needed to provide for attainment in                 such cases, emissions reductions may be               appropriate that state agencies develop
                                                the Area, since ACHD’s modeling                         required from various types and                       a comprehensive program to identify
                                                indicates that its plan will provide for                locations of sources. The relationship                sources of violations of the SO2 NAAQS
                                                attainment without reduction of any                     between SO2 and sources is much more                  and undertake an aggressive follow-up
                                                portion of background concentrations                    defined, and usually there is a single                for compliance and enforcement.
                                                attributable to these sources.                          step between pre-control nonattainment                   The contingency measures in
                                                   EPA is proposing to approve ACHD’s                   and post-control attainment. Therefore,               Pennsylvania’s October 3, 2017
                                                determination that the SO2 control                      EPA interpreted RFP for SO2 as                        submittal are designed to keep the
                                                strategies at the USS Mon Valley Works                  adherence to an ambitious compliance                  Allegheny Area from triggering an
                                                facilities—Clairton, Edgar Thomson and                  schedule in both the 1994 SO2                         exceedance or violation of the SO2
                                                Irvin plants and Harsco Metals                          Guideline Document and the 2014 SO2                   NAAQS. In the attainment plan, ACHD
                                                constitute RACM/RACT for each source                    Nonattainment Guidance. The control                   states that if an ambient air quality
                                                in the Allegheny Area based on the                      measures for attainment of the 2010 SO2               monitor measures enough exceedances
                                                modeling analysis previously described                  NAAQS included in Pennsylvania’s                      in a consecutive three-year period that
                                                and ACHD’s evaluation of technically                    submittal were modeled by ACHD to                     would cause a design value to exceed
                                                and economically feasible controls.                     achieve attainment of the NAAQS. The
                                                   Pennsylvania has requested that                                                                            the 75 ppb standard, ACHD would
                                                                                                        ACHD permits which require these                      conduct a thorough analysis in order to
                                                portions of the installation permits for                control measures to be effective on or
                                                the USS Mon Valley Works facilities—                                                                          identify the sources of the violation and
                                                                                                        before October 4, 2018 (including
                                                Clairton, Edgar Thomson and Irvin                                                                             bring the area back into compliance
                                                                                                        specific emission limits and compliance
                                                plants and Harsco Metals be approved                                                                          with the NAAQS. ACHD states that the
                                                                                                        parameters) show the resulting emission
                                                into the Allegheny County portion of                                                                          root cause analysis will begin
                                                                                                        reductions to be achieved as
                                                the Pennsylvania SIP. Upon approval,                                                                          immediately upon verification of a
                                                                                                        expeditiously as practicable for the
                                                the emission limits listed in the                                                                             violation, will include analysis of
                                                                                                        Area. As a result, based on air quality
                                                installation permits and corresponding                                                                        source and meteorological conditions
                                                                                                        modeling, ACHD projected these control
                                                compliance parameters found in the                                                                            contributing to the violation, and will
                                                                                                        measures will yield a sufficient
                                                installation permits for Clairton, Edgar                                                                      take no longer than 10 days to complete.
                                                                                                        reduction in SO2 emissions from the
                                                Thomson, Irvin and Harsco Metals will                                                                         In its plan, sources identified by ACHD
                                                                                                        major sources in the Allegheny Area to
                                                become permanent and enforceable SIP                    show attainment of the SO2 NAAQS for                  as most likely contributing to the
                                                measures to meet the requirements of                    the Allegheny Area. EPA has found                     violation will have 10 days from
                                                the CAA. After considering ACHD’s                       ACHD’s attainment modeling for the                    notification to submit a written system
                                                submitted information, EPA, therefore,                  Area to be in accordance with CAA                     audit report which details the operating
                                                concludes Pennsylvania’s October 3,                     requirements. EPA finds the control                   parameters of all SO2 emission sources
                                                2017, SIP submittal for the Area meets                  measures proposed will be implemented                 for the four 5-day periods up to and
                                                the RACM/RACT and emission                              as expeditiously as practicable by                    including the dates which the monitor
                                                limitation and other control measure                    October 4, 2018 according to the terms                registered exceedances of the SO2
                                                requirements of section 172(c) of the                   of the permits for the affected facilities.           NAAQS. According to the attainment
                                                CAA.                                                    Therefore, EPA has determined that                    plan, sources must recommend SO2
                                                                                                        Pennsylvania’s SO2 attainment plan for                control strategies for each affected unit
                                                E. RFP Plan                                                                                                   in the audit report. Once ACHD receives
                                                                                                        the Allegheny Area fulfills the RFP
                                                   Section 172(c)(2) of the CAA requires                requirements for the Allegheny Area.                  the audit report(s), a 30-day evaluation
                                                an attainment plan to include a                         EPA proposes to approve                               period will begin in which ACHD will
                                                demonstration that shows reasonable                     Pennsylvania’s attainment plan with                   investigate the audit findings and
                                                further progress (i.e., RFP) for meeting                respect to the RFP requirements.                      recommended control strategies. The
                                                air quality standards will be achieved                                                                        30-day evaluation period will be
                                                through generally linear incremental                    F. Contingency Measures                               followed by a 30-day consultation
                                                improvement in air quality. Section                        In accordance with section 172(c)(9)               period with the sources. Additional
                                                171(1) of the CAA defines RFP as ‘‘such                 of the CAA, contingency measures are                  control measures will be implemented
                                                annual incremental reductions in                        required as additional measures to be                 as expeditiously as possible to bring the
                                                emissions of the relevant air pollutant as              implemented in the event that an area                 Area back into compliance. If a permit
                                                are required by this part (part D) or may               fails to meet the RFP requirements or                 modification is necessary, ACHD has
                                                reasonably be required by EPA for the                   fails to attain the standard by its                   the statutory authority under ACHD
                                                purpose of ensuring attainment of the                   attainment date. These measures must                  Rules and Regulations, Article XXI—Air
khammond on DSK30JT082PROD with PROPOSAL




                                                applicable NAAQS by the applicable                      be fully adopted rules or control                     Pollution Control to amend and issue a
                                                attainment date.’’ As stated originally in              measures that can be implemented                      final permit. Any new emission limits
                                                the 1994 SO2 Guidelines Document 13                     quickly and without additional EPA or                 would also be submitted to EPA as a SIP
                                                                                                        state action if the area fails to meet RFP            revision. In addition, ACHD has the
                                                  13 SO Guideline Document, U.S. Environmental
                                                        2                                               requirements or fails to meet its                     regulatory authority to take any action it
                                                Protection Agency, Office of Air Quality Planning
                                                and Standards, Research Triangle Park, NC 27711,
                                                                                                        attainment date, and should contain                   deems necessary or proper for the
                                                EPA–452/R–94–008, February 1994. Located at:            trigger mechanisms and an                             effective enforcement of rules and
                                                http://www.epa.gov/ttn/oarpg/t1pgm.html.                implementation schedule. However,                     regulations; such actions include the


                                           VerDate Sep<11>2014   16:52 Nov 16, 2018   Jkt 247001   PO 00000   Frm 00027   Fmt 4702   Sfmt 4702   E:\FR\FM\19NOP1.SGM   19NOP1


                                                58218                Federal Register / Vol. 83, No. 223 / Monday, November 19, 2018 / Proposed Rules

                                                issuance of orders (i.e., enforcement                   § 2102.06 also incorporates by reference              remove EPA’s duty to implement a FIP
                                                orders and orders to take corrective                    applicable provisions of PADEP’s NNSR                 for this Area.
                                                action to address air pollution or the                  regulations codified at 25 Pa. Code
                                                                                                                                                              VII. Incorporation by Reference
                                                danger of air pollution from a source)                  Chapter 127, Subchapter E. PADEP’s
                                                and the assessment of civil penalties.                  NNSR regulations in 25 Pa. Code                          In this document, EPA is proposing to
                                                ACHD’s regulations for enforcement,                     Chapter 127, Subchapter E were                        include in a final EPA rule regulatory
                                                ACHD Article XXI, Part I, sections                      previously approved into the                          text that includes incorporation by
                                                2109.01–2109.06 and 2109.10, provide                    Pennsylvania SIP, with the most recent                reference. In accordance with
                                                ACHD authority to enforce its                           revision updating the regulations to                  requirements of 1 CFR 51.5, EPA is
                                                regulations, permits and orders.                        meet EPA’s 2002 NSR reform                            proposing to incorporate by reference
                                                Pursuant to these regulations, ACHD has                 regulations effective on May 14, 2012                 portions of the installation permits
                                                authority, inter alia, to inspect facilities,           (77 FR 28261). A discussion of the                    issued by ACHD with USS facilities at
                                                seek penalties for violations, enter                    specific PADEP provisions incorporated                Clairton, Edgar Thomson and Irvin and
                                                enforcement orders, and revoke permits.                 by reference into ACHD Article XXI can                with Harsco Metals. This includes
                                                These regulations are included in the                   be found in Pennsylvania’s October 3,                 emission limits and associated
                                                Pennsylvania SIP. See 67 FR 68935                       2017 submittal found under Docket ID                  compliance parameters, recording-
                                                (November 14, 2002).                                    No. EPA–R03–OAR–2017–0730. These                      keeping and reporting. EPA has made,
                                                   EPA finds that ACHD has a                            rules provide for appropriate NNSR                    and will continue to make, these
                                                comprehensive program included in the                   permitting as required by CAA sections                materials generally available through
                                                Pennsylvania SIP to identify sources of                 172(c)(5) and 173 and 40 CFR 51.165 for               http://www.regulations.gov and at the
                                                violations of the SO2 NAAQS and to                      SO2 sources undergoing construction or                EPA Region III Office (please contact the
                                                undertake an aggressive follow up for                   major modification in the Allegheny                   person identified in the ‘‘For Further
                                                compliance and enforcement. Therefore,                  Area without need for modification of                 Information Contact’’ section of this
                                                EPA proposes that the contingency                       the approved rules. Therefore, EPA                    proposed rulemaking for more
                                                measures submitted by Pennsylvania                      concludes that Allegheny County’s SIP-                information).
                                                follow the 2014 SO2 Nonattainment                       approved NNSR program meets the
                                                Guidance and meet the section 172(c)(9)                                                                       VIII. Statutory and Executive Order
                                                                                                        requirements of section 172(c)(5) for this            Reviews
                                                requirements.                                           Area.
                                                G. New Source Review 14                                                                                          Under the CAA, the Administrator is
                                                                                                        VI. EPA’s Proposed Action                             required to approve a SIP submission
                                                  Section 172(c)(5) of the CAA requires                    EPA is proposing to approve                        that complies with the provisions of the
                                                that an attainment plan require permits                 Pennsylvania’s attainment plan SIP                    CAA and applicable Federal regulations.
                                                for the construction and operation of                   revision for the Allegheny Area, as                   42 U.S.C. 7410(k); 40 CFR 52.02(a).
                                                new or modified major stationary                        submitted through ACHD and PADEP to                   Thus, in reviewing SIP submissions,
                                                sources in a nonattainment area. In                     EPA on October 3, 2017, for the purpose               EPA’s role is to approve state choices,
                                                Allegheny County, NNSR procedures                       of demonstrating attainment of the 2010               provided that they meet the criteria of
                                                and conditions for which new major                      1-hour SO2 NAAQS. Specifically, EPA                   the CAA. Accordingly, this action
                                                stationary sources or major                             is proposing to approve the base year                 merely approves state law as meeting
                                                modifications may obtain a                              emissions inventory, a modeling                       Federal requirements and does not
                                                preconstruction permit are stipulated in                demonstration of SO2 attainment, an                   impose additional requirements beyond
                                                the ACHD Rules and Regulations,                         analysis of RACM/RACT, a RFP plan,                    those imposed by state law. For that
                                                Article XXI, Air Pollution Control,                     and contingency measures for the                      reason, this proposed action:
                                                § 2102.06, ‘‘Major Sources Locating in or               Allegheny Area and is proposing that                     • Is not a ‘‘significant regulatory
                                                Impacting a Nonattainment Area’’                        the Pennsylvania SIP revision has met                 action’’ subject to review by the Office
                                                which was previously approved into the                  the requirements for NNSR for the 2010                of Management and Budget under
                                                Pennsylvania SIP, with the most recent                  1-hour SO2 NAAQS. Additionally, EPA                   Executive Orders 12866 (58 FR 51735,
                                                revision effective March 30, 2015 (80 FR                is proposing to approve into the                      October 4, 1993) and 13563 (76 FR 3821,
                                                16570). ACHD Rules and Regulations,                     Pennsylvania SIP specific SO2 emission                January 21, 2011);
                                                Article XXI, Air Pollution Control,                     limits and compliance parameters in                      • Is not an Executive Order 13771 (82
                                                   14 The CAA new source review (NSR) program is
                                                                                                        permits established for the SO2 sources               FR 9339, February 2, 2017) regulatory
                                                composed of three separate programs: Prevention of      impacting the Allegheny Area.                         action because SIP approvals are
                                                significant deterioration (PSD), NNSR, and Minor           EPA has determined that                            exempted under Executive Order 12866;
                                                NSR. PSD is established in part C of title I of the     Pennsylvania’s SO2 attainment plan for                   • Does not impose an information
                                                CAA and applies in areas that meet the NAAQS—                                                                 collection burden under the provisions
                                                ‘‘attainment areas’’—as well as areas where there is
                                                                                                        the 2010 1-hour SO2 NAAQS for the
                                                insufficient information to determine if the area       Allegheny Area meets the applicable                   of the Paperwork Reduction Act (44
                                                meets the NAAQS—‘‘unclassifiable areas.’’ The           requirements of the CAA and EPA’s                     U.S.C. 3501 et seq.);
                                                NNSR program is established in part D of title I of     2014 SO2 Nonattainment Guidance.                         • Is certified as not having a
                                                the CAA and applies in areas that are not in                                                                  significant economic impact on a
                                                attainment of the NAAQS—‘‘nonattainment areas.’’
                                                                                                        Thus, EPA is proposing to approve
                                                The Minor NSR program addresses construction or         Pennsylvania’s attainment plan for the                substantial number of small entities
                                                modification activities that do not qualify as          Allegheny Area as submitted on October                under the Regulatory Flexibility Act (5
khammond on DSK30JT082PROD with PROPOSAL




                                                ‘‘major’’ and applies regardless of the designation     3, 2017. EPA’s analysis for this                      U.S.C. 601 et seq.);
                                                of the area in which a source is located. Together,
                                                these programs are referred to as the NSR programs.
                                                                                                        proposed action is discussed in Section                  • Does not contain any unfunded
                                                Section 173 of the CAA lays out the NNSR program        V of this proposed rulemaking. EPA is                 mandate or significantly or uniquely
                                                for preconstruction review of new major sources or      soliciting public comments on the                     affect small governments, as described
                                                major modifications to existing sources, as required    issues discussed in this document.                    in the Unfunded Mandates Reform Act
                                                by CAA section 172(c)(5). The programmatic
                                                elements for NNSR include, among other things,
                                                                                                        These comments will be considered                     of 1995 (Pub. L. 104–4);
                                                compliance with the lowest achievable emissions         before taking final action. Final                        • Does not have Federalism
                                                rate and the requirement to obtain emissions offsets.   approval of this SIP submittal will                   implications as specified in Executive


                                           VerDate Sep<11>2014   16:52 Nov 16, 2018   Jkt 247001   PO 00000   Frm 00028   Fmt 4702   Sfmt 4702   E:\FR\FM\19NOP1.SGM   19NOP1


                                                                     Federal Register / Vol. 83, No. 223 / Monday, November 19, 2018 / Proposed Rules                                          58219

                                                Order 13132 (64 FR 43255, August 10,                    SUMMARY:     NMFS proposes specifications             Dr. Christopher M. Moore, Executive
                                                1999);                                                  for the 2019 blueline tilefish fishery                Director, Mid-Atlantic Fishery
                                                  • Is not an economically significant                  north of the North Carolina/Virginia                  Management Council, Suite 201, 800
                                                regulatory action based on health or                    border and projected specifications for               North State Street, Dover, DE 19901.
                                                safety risks subject to Executive Order                 2020 and 2021. The proposed action is                 These documents are also accessible via
                                                13045 (62 FR 19885, April 23, 1997);                    intended to establish allowable harvest               the internet at www.mafmc.org.
                                                  • Is not a significant regulatory action              levels and other management measures                  FOR FURTHER INFORMATION CONTACT:
                                                subject to Executive Order 13211 (66 FR                 to prevent overfishing while allowing                 Douglas Potts, Fishery Policy Analyst,
                                                28355, May 22, 2001);                                   optimum yield, consistent with the
                                                  • Is not subject to requirements of                                                                         (978) 281–9341.
                                                                                                        Magnuson-Stevens Fishery
                                                Section 12(d) of the National                           Conservation and Management Act and                   SUPPLEMENTARY INFORMATION:
                                                Technology Transfer and Advancement                     the Tilefish Fishery Management Plan.                 Background
                                                Act of 1995 (15 U.S.C. 272 note) because                It is also intended to inform the public
                                                application of those requirements would                 of these proposed specifications for the                 The blueline tilefish fishery north of
                                                be inconsistent with the CAA; and                       2019 fishing year and projected                       the North Carolina/Virginia border is
                                                  • Does not provide EPA with the                       specifications for 2020–2021.                         managed by the Mid-Atlantic Fishery
                                                discretionary authority to address, as                                                                        Management Council under the Tilefish
                                                                                                        DATES: Comments must be received by
                                                appropriate, disproportionate human                                                                           Fishery Management Plan (FMP), which
                                                                                                        5 p.m. local time, on December 4, 2018.
                                                health or environmental effects, using                                                                        outlines the Council’s process for
                                                practicable and legally permissible                     ADDRESSES: You may submit comments
                                                                                                                                                              establishing annual specifications.
                                                methods, under Executive Order 12898                    on this document, identified by NOAA–
                                                                                                                                                              Blueline tilefish south of the North
                                                (59 FR 7629, February 16, 1994).                        NMFS–2018–0115, by either of the
                                                                                                                                                              Carolina/Virginia border are managed
                                                  In addition, this proposed rule,                      following methods:
                                                                                                                                                              by the South Atlantic Fishery
                                                concerning the SO2 attainment plan for                     Electronic Submission: Submit all
                                                                                                                                                              Management Council under the Snapper
                                                the Allegheny Area in Pennsylvania,                     electronic public comments via the
                                                                                                                                                              Grouper FMP.
                                                does not have tribal implications as                    Federal e-Rulemaking Portal.
                                                                                                           1. Go to www.regulations.gov/#                        The Tilefish FMP requires the Mid-
                                                specified by Executive Order 13175 (65                                                                        Atlantic Council to recommend
                                                FR 67249, November 9, 2000), because                    !docketDetail;D=NOAA-NMFS-2018-
                                                                                                        0115,                                                 acceptable biological catch (ABC),
                                                the SIP is not approved to apply in                                                                           annual catch limit (ACL), annual catch
                                                Indian country located in the state, and                   2. Click the ‘‘Comment Now!’’ icon,
                                                                                                        complete the required fields.                         target (ACT), total allowable landings
                                                EPA notes that it will not impose                                                                             (TAL), and other management measures
                                                substantial direct costs on tribal                         3. Enter or attach your comments.
                                                                                                                                                              for the commercial and recreational
                                                governments or preempt tribal law.                      —OR—                                                  sectors of the fishery, for up to three
                                                List of Subjects in 40 CFR Part 52                         Mail: Submit written comments to                   years at a time. The Council’s Scientific
                                                  Environmental protection, Air                         Michael Pentony, Regional                             and Statistical Committee (SSC)
                                                pollution control, Incorporation by                     Administrator, National Marine                        provides an ABC recommendation to
                                                reference, Reporting and recordkeeping                  Fisheries Service, 55 Great Republic                  the Council to derive these catch limits.
                                                requirements, Sulfur oxides.                            Drive, Gloucester, MA 01930. Mark the                 The Council makes recommendations to
                                                                                                        outside of the envelope: ‘‘Comments on                NMFS that cannot exceed the
                                                   Authority: 42 U.S.C. 7401 et seq.                                                                          recommendation of its SSC. The
                                                                                                        the Proposed Rule for Blueline Tilefish
                                                  Dated: November 1, 2018.                              Specifications.’’                                     Council’s recommendations must
                                                Cosmo Servidio,                                            Instructions: Comments sent by any                 include supporting documentation
                                                Regional Administrator, Region III.                     other method, to any other address or                 concerning the environmental,
                                                [FR Doc. 2018–25079 Filed 11–16–18; 8:45 am]            individual, or received after the end of              economic, and social impacts of the
                                                BILLING CODE 6560–50–P                                  the comment period, may not be                        recommendations. We are responsible
                                                                                                        considered by NMFS. All comments                      for reviewing these recommendations to
                                                                                                        received are part of the public record                ensure that they achieve the FMP
                                                                                                        and will generally be posted for public               objectives and are consistent with all
                                                DEPARTMENT OF COMMERCE
                                                                                                        viewing on www.regulations.gov                        applicable laws. Following review,
                                                National Oceanic and Atmospheric                        without change. All personal identifying              NMFS publishes the final specifications
                                                Administration                                          information (e.g., name, address, etc.),              in the Federal Register.
                                                                                                        confidential business information, or                    A benchmark stock assessment was
                                                50 CFR Part 648                                         otherwise sensitive information                       completed in late 2017 for the blueline
                                                                                                        submitted voluntarily by the sender will              tilefish population along the entire East
                                                [Docket No. 181022971–01]
                                                                                                        be publicly accessible. NMFS will                     Coast through the Southeast Data,
                                                RIN 0648–BI57                                           accept anonymous comments (enter                      Assessment, and Review process
                                                                                                        ‘‘N/A’’ in the required fields if you wish            (SEDAR 50). Within the assessment, the
                                                Fisheries of the Northeastern United                    to remain anonymous).                                 coast-wide population was modeled
                                                States; Mid-Atlantic Blueline Tilefish                     A draft environmental assessment                   separately north and south of Cape
                                                Fishery; 2019 and Projected 2020–2021                   (EA) has been prepared for this action                Hatteras, North Carolina, because of
khammond on DSK30JT082PROD with PROPOSAL




                                                Specifications                                          that describes the proposed measures                  data limitations within the northern
                                                AGENCY:  National Marine Fisheries                      and other considered alternatives, as                 area. To assist in developing an ABC
                                                Service (NMFS), National Oceanic and                    well as provides an analysis of the                   recommendation, the Mid- and South
                                                Atmospheric Administration (NOAA),                      impacts of the proposed measures and                  Atlantic Councils’ SSCs, as well as staff
                                                Commerce.                                               alternatives. Copies of the specifications            from the NMFS Northeast and Southeast
                                                                                                        document, including the EA and the                    Fisheries Science Centers formed a joint
                                                ACTION: Proposed rule; request for
                                                                                                        Initial Regulatory Flexibility Analysis               subcommittee to examine available
                                                comments.
                                                                                                        (IRFA), are available on request from                 information for the region north of Cape


                                           VerDate Sep<11>2014   16:52 Nov 16, 2018   Jkt 247001   PO 00000   Frm 00029   Fmt 4702   Sfmt 4702   E:\FR\FM\19NOP1.SGM   19NOP1



Document Created: 2018-11-17 02:46:45
Document Modified: 2018-11-17 02:46:45
CategoryRegulatory Information
CollectionFederal Register
sudoc ClassAE 2.7:
GS 4.107:
AE 2.106:
PublisherOffice of the Federal Register, National Archives and Records Administration
SectionProposed Rules
ActionProposed rule.
DatesWritten comments must be received on or before December 19, 2018.
ContactLeslie Jones Doherty, (215) 814-3409, or by email at [email protected]
FR Citation83 FR 58206 
CFR AssociatedEnvironmental Protection; Air Pollution Control; Incorporation by Reference; Reporting and Recordkeeping Requirements and Sulfur Oxides

2024 Federal Register | Disclaimer | Privacy Policy
USC | CFR | eCFR