[Federal Register Volume 85, Number 228 (Wednesday, November 25, 2020)]
[Proposed Rules]
[Pages 75273-75280]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2020-25827]


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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 52

[EPA-R05-OAR-2016-0074; FRL-10016-90-Region 5]


Air Plan Approval; Wisconsin; Partial Approval and Partial 
Disapproval of the Oneida County SO2 Nonattainment Area Plan

AGENCY: Environmental Protection Agency (EPA).

ACTION: Proposed rule.

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SUMMARY: The Environmental Protection Agency (EPA) is proposing to 
partially approve and partially disapprove a revision to the Wisconsin 
State Implementation Plan (SIP) for attaining the 2010 primary, health-
based 1-hour sulfur dioxide (SO2) national ambient air 
quality standard (NAAQS or ``standard'') for the Oneida County 
SO2 nonattainment area. This SIP revision (hereinafter 
referred to as Wisconsin's Oneida County SO2 plan or plan) 
includes Wisconsin's attainment demonstration and other attainment 
planning elements required under the Clean Air Act (CAA). EPA is 
proposing to approve some elements of the Oneida County SO2 
plan and disapprove some elements of the plan, including the attainment 
demonstration, since it contains facility credit for a stack height 
that does not meet the regulations for good engineering practice stack 
height regarding the prohibition of air pollution dispersion 
techniques.

DATES: Comments must be received on or before December 28, 2020.

ADDRESSES: Submit your comments, identified by Docket ID No. EPA-R05-
OAR-2016-0074 at http://www.regulations.gov, or via email to 
Aburano.Douglas@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: Jennifer Liljegren, Physical 
Scientist, Attainment Planning and Maintenance Section, Air Programs 
Branch (AR-18J), Environmental Protection Agency, Region 5, 77 West 
Jackson Boulevard, Chicago, Illinois 60604, (312) 886-6832, 
Liljegren.Jennifer@epa.gov. The EPA Region 5 office is open from 8:30 
a.m. to 4:30 p.m., Monday through Friday, excluding Federal holidays 
and facility closures due to COVID-19.

SUPPLEMENTARY INFORMATION:

I. Why was Wisconsin required to submit a plan for the Oneida County 
SO2 nonattainment area?

    On June 22, 2010, EPA published a new 1-hour primary SO2 
NAAQS of 75 parts per billion (ppb). This standard 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

[[Page 75274]]

concentrations does not exceed 75 ppb, as determined in accordance with 
appendix T of 40 CFR part 50.\1\ On August 5, 2013, EPA designated a 
first set of 29 areas of the country as nonattainment for the 2010 
SO2 NAAQS, including the Oneida County SO2 
nonattainment area in Wisconsin.\2\ These area designations became 
effective on October 4, 2013. Section 191(a) of the CAA directs states 
to submit SIPs for areas designated as nonattainment for the 
SO2 NAAQS (hereinafter called ``plans'' or ``nonattainment 
plans'') to EPA within 18 months of the effective date of the 
designation, i.e., by no later than April 4, 2015 in this case. Under 
CAA section 192(a), these plans are required to have measures that will 
provide for attainment of the NAAQS as expeditiously as practicable, 
but no later than five years from the effective date of designation, 
i.e., October 4, 2018, for the Oneida County SO2 
nonattainment area.
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    \1\ 75 FR 35520, codified at 40 CFR 50.17(a)-(b).
    \2\ 78 FR 47191, codified at 40 CFR part 81, subpart C.
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    In response to the requirement for SO2 nonattainment 
plan submittals, Wisconsin submitted to EPA the Oneida County 
SO2 plan on January 22, 2016, and submitted supplemental 
information on July 18, 2016, and November 29, 2016.
    For reasons described in the following sections, EPA is proposing 
to disapprove portions of the Oneida County SO2 plan. 
Finalization of this action would start sanctions clocks which can be 
stopped only if the conditions of EPA's regulations at 40 CFR 52.31 are 
met.
    If EPA finalizes the disapproval that EPA is proposing here, that 
action would initiate a new sanctions clock under section 179, 
providing for new source sanctions if EPA has not approved a revised 
plan within 18 months after final disapproval, and providing for 
highway funding sanctions if EPA has not approved a revised plan within 
6 months thereafter, as well as initiating an obligation for EPA to 
promulgate a Federal implementation plan within 24 months unless in the 
meantime Wisconsin has submitted and EPA has approved a plan addressing 
these attainment planning requirements.
    The remainder of this preamble describes the requirements that 
nonattainment plans must meet in order to obtain EPA approval, provides 
the history and description of EPA's stack height regulations (which 
are pertinent to Wisconsin's plan for Oneida County), provides a review 
of the Oneida County SO2 plan with respect to these 
requirements, and describes EPA's proposed action on the plan.
    On September 10, 2020, following discussions between EPA and 
Wisconsin regarding the requirements of EPA's stack height regulations, 
Wisconsin sent EPA a letter, included in the docket for this proposed 
action, expressing a desire for additional analyses of the ``formula 
GEP height'' (see 40 CFR 51.100(ii)(2) for EPA's regulations addressing 
formula height demonstrations) for the Ahlstrom-Munksjo facility and 
committing to adopt a limit consistent with EPA's stack height 
regulations by April 1, 2021. However, this letter does not provide any 
technical information that affects EPA's review of Wisconsin's existing 
plan that was submitted to EPA, and the commitment for an additional 
submittal does not serve as a substitute for a plan with suitable, 
enforceable limits. Therefore, this recent letter does not alter EPA's 
review of Wisconsin's Oneida County SO2 plan.

II. Requirements for Nonattainment Plans

    Nonattainment plans for SO2 must meet the applicable 
requirements of the CAA, specifically sections 110, 172, 191, and 192. 
EPA's regulations governing nonattainment SIP submissions are set forth 
at 40 CFR part 51, with specific procedural requirements and control 
strategy requirements codified at subparts F and G, respectively. Soon 
after Congress enacted the 1990 Amendments to the CAA, EPA issued 
comprehensive guidance on SIP revisions in the ``General Preamble for 
the Implementation of Title I of the CAA Amendments of 1990'' 
(``General Preamble'').\3\ Among other things, the General Preamble 
addressed SO2 SIP submissions and fundamental principles for 
SIP control strategies.\4\ On April 23, 2014, EPA issued recommended 
guidance for meeting the statutory requirements in SO2 SIP 
submissions in a document entitled ``Guidance for 1-Hour SO2 
Nonattainment Area SIP Submissions'' (``2014 SO2 
Guidance''). In the 2014 SO2 Guidance, EPA described the 
statutory requirements of CAA section 172(c) for a complete 
nonattainment plan, including: An accurate emissions inventory of 
current emissions for all sources of SO2 within the 
nonattainment area; an attainment demonstration; a demonstration of 
RFP; implementation of RACM (including RACT); new source review; 
enforceable emission limitations and control measures; and adequate 
contingency measures for the affected area.
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    \3\ 57 FR 13498 (April 16, 1992).
    \4\ Id. at 13548-13549, 13567-13568.
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    For EPA to fully approve a SIP revision as meeting the requirements 
of CAA sections 110, 172, 191, and 192, and EPA's regulations at 40 CFR 
part 51, the plan for an affected area must demonstrate to EPA's 
satisfaction that each of the aforementioned requirements has been met. 
Under CAA section 110(l), EPA may not approve a plan that would 
interfere with any applicable requirement concerning NAAQS attainment 
and RFP, or any other applicable requirement. Under CAA section 193, 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 that is nonattainment for any air pollutant may be modified in 
any manner unless it ensures equivalent or greater emission reductions 
of such air pollutant.
    Sections 172(c)(1) and 172(c)(6) of the CAA direct states with 
areas designated as nonattainment to demonstrate that the submitted 
plan and the emissions limitations and control measures in it provide 
for attainment of the NAAQS. 40 CFR part 51, subpart G further 
delineates the control strategy requirements that plans must meet, and 
EPA has long required that all SIPs and control strategies reflect four 
fundamental principles of quantification, enforceability, 
replicability, and accountability.\5\ SO2 nonattainment 
plans must consist of two components: (1) Emission limits and other 
control measures that ensure implementation of permanent, enforceable, 
and necessary emission controls, and (2) a modeling analysis that meets 
the requirements of 40 CFR part 51, appendix W and demonstrates that 
these emission limits and control measures provide for timely 
attainment of the primary SO2 NAAQS as expeditiously as 
practicable, but no later than the attainment date for the affected 
area. In cases where the necessary emission limits have not previously 
been made a part of the state's SIP or have not otherwise become 
federally enforceable, the plan needs to include the necessary 
enforceable limits in an adopted form suitable for incorporation into 
the SIP in order for the plan to be approved by EPA. 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

[[Page 75275]]

and must be quantifiable (i.e., a specific amount of emission reduction 
can be ascribed to the measures), fully enforceable (i.e., specifying 
clear, unambiguous and measurable requirements for which compliance can 
be practicably determined), replicable (i.e., the procedures for 
determining compliance are sufficiently specific and objective so that 
two independent entities applying the procedures would obtain the same 
result), and accountable (i.e., source specific limits must be 
permanent and must reflect the assumptions used in the SIP 
demonstrations).
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    \5\ Id. at 13567-13568.
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    EPA's 2014 SO2 Guidance recommends that the emission 
limits be expressed as short-term average limits not to exceed the 
averaging time for the applicable NAAQS that the limit is intended to 
help maintain (e.g., addressing emissions averaged over one hour for 
the 2010 SO2 NAAQS), but it also describes the option to 
utilize emission limits with longer averaging times of up to 30 days as 
long as the state meets various recommended criteria.\6\ The 2014 
SO2 Guidance recommends that, should states and sources 
utilize longer averaging times (such as, for example, 24-hours or 30 
days), 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. Additional 
discussion of EPA's rationale for approving longer-term average limits 
in selected cases has been provided in several notices of proposed 
rulemaking, for example for the Pekin, Illinois area (see 82 FR 46434, 
Oct. 5, 2017), for the Steubenville, Ohio-West Virginia area (see 84 FR 
29456, June 24, 2019), and for the Central New Hampshire area (see 82 
FR 45242, Sep. 28, 2017).
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    \6\ 2014 SO2 Guidance, 22-39.
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    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 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 the 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 that may affect attainment in the area) is technically 
appropriate. This approach is also efficient and effective in 
demonstrating attainment in nonattainment areas because it takes into 
consideration combinations of meteorological and source operating 
conditions that may contribute to peak ground-level concentrations of 
SO2.
    Preferred air quality models for use in regulatory applications are 
described in appendix A of EPA's ``Guideline on Air Quality Models'' 
(appendix A of 40 CFR part 51, appendix W (``appendix W'')).\7\ In 
general, nonattainment SIP submissions must demonstrate the adequacy of 
the selected control strategy using the applicable air quality model 
designated in appendix W.\8\ However, where an air quality model 
specified in appendix W is inappropriate for the particular 
application, the model may be modified or another model substituted, if 
EPA approves the modification or substitution.\9\ In 2005, EPA 
promulgated the American Meteorological Society/Environmental 
Protection Agency Regulatory Model (AERMOD) as the Agency's preferred 
near-field dispersion model for a wide range of regulatory applications 
addressing stationary sources (e.g., in estimating SO2 
concentrations) in all types of terrain based on an extensive 
developmental and performance evaluation. Supplemental guidance on 
modeling for purposes of demonstrating attainment of the SO2 
standard is provided in appendix A of the 2014 SO2 Guidance. 
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 the 2014 
SO2 Guidance is generally necessary for the attainment 
demonstration to offer adequately reliable assurance that the plan 
provides for attainment.
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    \7\ EPA published revisions to appendix W on January 17, 2017, 
82 FR 5182.
    \8\ 40 CFR 51.112(a)(1).
    \9\ 40 CFR 51.112(a)(2); appendix W, section 3.2.
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    The meteorological data used in the analysis should generally be 
processed with the most recent version of AERMET, which is the 
meteorological data preprocessor for AERMOD. Estimated concentrations 
should include ambient background concentrations, follow the form of 
the standard, and be calculated as described in EPA's August 23, 2010 
clarification memorandum.\10\
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    \10\ ``Applicability of Appendix W Modeling Guidance for the 1-
hr SO2 National Ambient Air Quality Standard'' (August 
23, 2010).
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    Of particular relevance to Wisconsin's submittal are requirements 
in 40 CFR 51.100, generally referred to as the stack height 
regulations. These regulations, which implement CAA section 123, 
require that if the GEP stack height exceeds the height resulting from 
the 40 CFR 51.100(ii)(2) formulae and is determined based on the 
results of a special study, typically a fluid modeling or wind tunnel 
study, then additional requirements relating to emissions control must 
first be met. These additional requirements would result in a more 
stringent limit than that which is proposed for the Ahlstrom-Munksjo 
facility in the Wisconsin's Oneida County SO2 plan. The 
history and nature of the stack height regulations are described in the 
following section.

III. History and Nature of Stack Height Regulations

    Given the significance of the stack height regulations for EPA's 
review of Wisconsin's submittal, and given the distinctive nature of 
these regulations, a discussion of the history of these regulations is 
necessary to provide perspective on EPA's application of these 
requirements. Prior to the enactment of the CAA Amendments of 1977, 
some parties expressed the view that ``the solution to pollution is 
dilution.'' This viewpoint in effect argues that meeting air quality 
standards by building sufficiently tall stacks, thereby enhancing the 
degree of dispersion between the time a plume is released and the time 
the plume reaches ground level, should be an acceptable alternative to 
meeting air quality standards by reducing emissions. Other parties 
argued that dilution is not the solution to pollution, that the use of 
excessively tall stacks without any reduction to the atmospheric 
loading of pollutants should not be a permissible means for meeting air 
quality standards. Congress ultimately adopted the latter perspective, 
as reflected in its enactment of section 123 in its CAA Amendments of 
1977. As discussed in a court ruling upholding this interpretation of 
section 123, Congress ``refused to allow reliance'' on tall stacks 
because ``dispersion techniques do not reduce the amount of pollution 
in the air, but merely spread it around, exporting it to other areas . 
. . and exposing previously pristine areas to contamination.'' Sierra 
Club v. EPA, 719 F. 2d at 441 (D.C. Cir. 1983).
    The pertinent text of CAA section 123(a) indicates that the degree 
of emission limitation required for control of any air pollutant under 
an applicable implementation plan shall not be affected in any manner 
by so much of the stack height of any source as exceeds good 
engineering practice (as determined under regulations

[[Page 75276]]

promulgated by the Administrator). EPA's regulations implementing 
section 123 reside at 40 CFR 51.118-51.119, and in a series of 
definitions at 40 CFR 51.100(ff)-(nn). EPA's most recently promulgated 
regulations implementing section 123 were published on July 8, 1985 (50 
FR 27892). The preamble of EPA's notice promulgating these regulations 
help explain EPA's intent underlying its formulation of these 
regulations.
    The stack height regulations define several terms used in 
evaluating whether or not a plan is consistent with the provisions in 
section 123 and 40 CFR 51.118 prohibiting reliance on dispersion 
techniques, as defined in 40 CFR (hh)(1)-(2). The pertinent terms 
relate to creditable stack heights. GEP stack height is defined as the 
greatest among three values, based on three defined approaches for 
determining GEP stack height. The first approach, defined in 40 CFR 
51.100(ii)(1), uses a minimum GEP height of 65 meters. The second 
approach, defined in 40 CFR 51.100(ii)(2), defines GEP stack height by 
applying one of two formulae, as applicable based on the age of the 
stack, in which GEP stack height is calculated on the basis of building 
dimensions that influence how tall a stack is routinely warranted to 
avoid most of the downwash that the building creates. The first 
formula, defining GEP stack height based on an old equation developed 
for this purpose, is not germane to Wisconsin's plan. The second, 
pertinent equation (in 40 CFR 51.100(ii)(2)(ii)) is that the GEP stack 
height equals the height of the building plus 1.5 times the lesser of 
the height or the width of the building. The third approach, set forth 
in 40 CFR 51.100(ii)(3) and tied to the definitions of ``nearby'' and 
``excessive concentration'' at 40 CFR 51.100(jj)(2) and (kk)(1), 
respectively, uses neither of the formulae and defines GEP height based 
on the results of a special study, typically a fluid modeling or wind 
tunnel study, with the provision in section 51.100(kk)(1) that 
additional requirements relating to emissions control must first be 
met, namely control to the new source performance standard (NSPS) level 
or an alternative rate established if the NSPS is demonstrated to be 
infeasible. For clarity, this notice will describe the first and second 
approach as relying on the formula GEP height and the third approach as 
relying on the height determined by fluid modeling or wind tunnel 
study. More detailed guidance on these analyses is provided in guidance 
that EPA issued in conjunction with the stack height regulations.\11\
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    \11\ Guidance on this and related topics is provided in 
``Guidance for Determination of Good Engineering Practice Stack 
Height (Technical Support Document for the Stack Height 
Regulation),'' June 1985, EPA, Office of Air Quality Planning and 
Standards, EPA-450/4-80-023R, available at https://www3.epa.gov/ttn/scram/guidance/guide/gep.pdf.
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    In this third approach, the creditable stack height is defined in 
40 CFR 51.100(ii)(3) as the height demonstrated by a fluid model . . . 
which ensures that the emissions from a stack do not result in 
excessive concentrations of any air pollutant as a result of 
atmospheric downwash, wakes, or eddy effects created by the source 
itself, nearby structures or nearby terrain features. ``Nearby'' is 
defined in 40 CFR 51.100(jj)(2) as not greater than 0.8 km (\1/2\ mile) 
with a set of exceptions applying to terrain features (see 40 CFR 
51.100(jj)(2)). ``Excessive concentrations'' is then defined in 40 CFR 
51.100(kk)(1) for sources seeking credit for stack height exceeding 
[formula GEP height] as a maximum ground-level concentration due to 
emissions from a stack due in whole or part to downwash, wakes, and 
eddy effects produced by nearby structures or nearby terrain features 
which individually is at least 40 percent in excess of the maximum 
concentration experienced in the absence of such downwash, wakes, or 
eddy effects and which contributes to a total concentration due to 
emissions from all sources that is greater than an ambient air quality 
standard. The allowable emission rate to be used in making 
demonstrations under this part shall be prescribed by the new source 
performance standard that is applicable to the source category unless 
the owner or operator demonstrates that this emission rate is 
infeasible. Where such demonstrations are approved by the authority 
administering the SIP, an alternative emission rate shall be 
established in consultation with the source owner or operator.
    Thus, in cases where a source seeks credit for a stack height 
greater than formula GEP stack height, the stack height regulations 
require that the state first determine whether the air quality standard 
can be attained by applying suitable emission controls with credit for 
no more than formula GEP stack height. If so, then the facility does 
not have ``excessive concentrations'' with the stack at formula GEP 
height and no additional stack height is creditable. This feature is 
discussed further in the preamble to the 1985 regulations, which 
indicates that the EPA's 1976 stack height guidelines \12\ imposed 
special conditions (the installation of control technology) on stacks 
above formula height that were not imposed on lower stacks. The 
legislative history of the 1977 CAA Amendments cautioned that credit 
for stacks above formula height should be granted only in rare cases, 
and the Court of Appeals adopted this as one of the keystones of its 
opinion. The preamble to the 1985 regulations further indicated that 
for these reasons, EPA is requiring sources seeking credit for stacks 
above formula height to show by field studies or fluid modeling that 
this height is needed to avoid a 40 percent increase in concentrations 
due to downwash and that such an increase would result in exceedance of 
air quality standards. Finally, the preamble to the 1985 regulations 
indicated that this will restrict stack height credit in this context 
to cases where the downwash avoided is at levels specified by 
regulation or by act of Congress as possessing health or welfare 
significance.
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    \12\ These guidelines are available at https://nepis.epa.gov/Exe/ZyNET.exe/9100JWKU.txt?ZyActionD=ZyDocument&Client=EPA&Index=1976%20Thru%201980&Docs=&Query=&Time=&EndTime=&SearchMethod=1&TocRestrict=n&Toc=&TocEntry=&QField=&QFieldYear=&QFieldMonth=&QFieldDay=&UseQField=&IntQFieldOp=0&ExtQFieldOp=0&XmlQuery=&File=D%3A%5CZYFILES%5CINDEX%20DATA%5C76THRU80%5CTXT%5C00000016%5C9100JWKU.txt&User=ANONYMOUS&Password=anonymous&SortMethod=h%7C-&MaximumDocuments=1&FuzzyDegree=0&ImageQuality=r75g8/r75g8/x150y150g16/i425&Display=hpfr&DefSeekPage=x&SearchBack=ZyActionL&Back=ZyActionS&BackDesc=Results%20page&MaximumPages=1&ZyEntry=3.
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    That is, if fluid modeling showed that downwash with a formula GEP 
height stack increased concentrations by more than 40 percent but 
suitable controls would provide for attainment (or if no modeling was 
provided assessing whether suitable controls would provide for 
attainment or if the state did not adopt limits requiring suitable 
control), then the plan would not have justified a stack height above 
formula GEP height as being creditable. In that case, the attainment 
demonstration would be considered to rely on a prohibited dispersion 
technique, in contravention of CAA section 123.
    A common phrase in the debate leading to the 1985 regulations was 
``control first.'' Advocates for control first, notably Natural 
Resources Defense Council, Inc. (NRDC), urged that all candidates for 
taller stacks first be required to implement aggressive emissions 
control, and that sources only be granted credit for taller stacks if 
such control does not suffice to resolve air quality problems. The 
opposite

[[Page 75277]]

preference was to focus solely on air quality, to argue that EPA should 
approve plans that resolve air quality problems with taller stacks 
(particularly those plans that involve more than a 40 percent impact of 
building downwash) without regard to the degree of control that the 
source implements. EPA's 1985 regulations reflect a compromise between 
these two positions, in which requirements for ``control first'' apply 
to sources seeking credit for stacks taller than formula GEP height and 
do not apply to sources with stacks at or below formula GEP height. The 
U.S. Court of Appeals for the D.C. Circuit affirmed this compromise in 
Natural Resources Defense Council v. Thomas, 838 F. 2d 1224 (D.C. Cir. 
1988).
    The preamble to the 1985 regulations provides further discussion of 
the level of control that is mandated as a prerequisite for finding any 
stack height greater than the formula GEP height to be creditable. As a 
general matter, the NSPS associated with the subject source's source 
category are presumed to be the level of control to be adopted and to 
be used in any assessment of whether such emission controls and a 
creditable stack height in excess of the formula height is needed to 
eliminate any excessive concentrations (in combination with an 
assessment of the percentage impact of downwash). However, the 
regulations also provide the possibility of demonstrating that the NSPS 
are infeasible at the source, in which case an alternate control 
requirement must be adopted and used in evaluating whether the source's 
controlled emissions and a stack height above formula GEP height may be 
credited to avoid an excessive concentration. Footnote 6 of the 1985 
preamble (50 FR 27898) states that EPA will rely on its Best Available 
Retrofit Technology (BART) Guideline in reviewing any [demonstrations 
of NSPS infeasibility] and alternative emission limitations. That is, 
in cases where the NSPS is demonstrated to be infeasible, EPA will use 
the criteria in the BART Guideline to determine whether the plan 
adequately demonstrates the infeasibility of the NSPS and whether the 
limit that the state adopts qualifies as a suitable limit to use in 
evaluating whether excessive concentrations (i.e. violations of the air 
quality standard) remain that might warrant a creditable stack height 
that is higher than the formula GEP height. In either case, the 
analysis of whether credit for stack height above formula GEP height is 
warranted must be based on an assessment of whether the appropriately 
limited allowable emissions would nevertheless result in violation of 
the air quality standard. Since this demonstration must rely on 
allowable emissions, the SIP must include the appropriate limit, either 
the NSPS or a BART limit, as an adopted part of the plan. EPA's 
approach to implementing these provisions was affirmed by the U.S. 
Court of Appeals for the 9th Circuit, in Montana Sulphur & Chemical 
Company v. USEPA, 666 F. 3d 1174 (9th Cir. 2012).

IV. Review of Modeled Attainment Demonstration

    The majority of Wisconsin's submittal includes an assessment of the 
air quality impacts Wisconsin expected to result from emissions limits 
governing the Ahlstrom-Munksjo paper mill (formerly Expera Specialty 
Solutions LLC (Expera)), which Wisconsin found to be the primary 
SO2 source in the Oneida County nonattainment area based on 
its AERMOD dispersion model. This source is the only source in Oneida 
County listed in the 2017 National Emissions Inventory with more than 
100 tons per year of SO2 emissions. The plan accounts for 
two additional stationary sources, namely Red Arrow Products and the 
Packaging Corporation of America (PCA), but the emissions from these 
sources are subject to permanent, enforceable limits through existing 
title I construction permit requirements. These sources have minimal 
effect on area air quality, insofar as Red Arrow emits less than 10 
tons per year, and PCA, which emits about 50 tons per year, is over 30 
kilometers from the area of concern in Oneida County.
    Wisconsin's Oneida County SO2 plan includes a discussion 
of its modeling using AERMOD to determine the emissions that can be 
emitted from the Ahlstrom-Munksjo facility while still attaining the 
NAAQS (i.e. a modeled attainment demonstration). The model assumes 
maximum allowable emissions from Red Arrow and PCA, the other 
SO2 sources in the nonattainment area or within 50 
kilometers of the nonattainment area, as allowed by their Title I 
construction permits. This analysis used surface meteorological data 
from the Rhinelander-Oneida County Airport (KRHI) and upper air data 
from the Green Bay site. Although the Ahlstrom-Munksjo facility's 
boiler B26 formula GEP stack height according to the State's submittal 
is 75 meters, Wisconsin modeled the facility with a stack height of 90 
meters, based on a series of wind tunnel studies conducted by 
consultants to the facility showing that a 90 meter stack would reduce 
downwash effects down to a 40 percent impact on concentrations. 
Subsequently, Ahlstrom-Munksjo (formerly Expera) raised the stack from 
63.7 meters to 90 meters. However, as detailed above, emissions control 
requirements are a prerequisite to potentially receiving credit for a 
stack height that exceeds the height resulting from the 40 CFR 
51.100(ii)(2) formulae. These emissions control requirements (NSPS or 
BART) would result in a more stringent limit than that which is 
proposed for the Ahlstrom-Munksjo facility in Wisconsin's Oneida County 
SO2 plan.
    While many aspects of Wisconsin's modeling are consistent with the 
recommendations of appendix W, the submittal relies on a stack height 
and corresponding emission limitation that is contrary to and exceeds 
what is creditable under EPA's stack height regulations. Wisconsin's 
proposed GEP stack height exceeds formula GEP height without satisfying 
the associated requirements for establishing suitable control 
requirements and without demonstrating the degree to which a height 
above formula GEP height (if any) is necessary to avoid violations with 
application of the control requirements. Since this portion of the 
submittal therefore cannot be approved, EPA is not providing a full 
review of the various features of Wisconsin's attainment demonstration 
for the Oneida County SO2 nonattainment area (e.g. the 
methodology and parameters of the wind tunnel study with respect to 
relevant EPA guidance, the stack-specific downwash algorithm developed 
from the wind tunnel study and applied to Ahlstrom-Munksjo's boiler B26 
stack in AERMOD in lieu of the traditional downwash algorithm utilized 
in AERMOD, etc.).

V. SIP Strengthening Emission Limits

    As noted above, Wisconsin's Oneida County SO2 plan 
proposed a more stringent emission limit for the Ahlstrom-Munksjo 
facility than that which previously applied. Historically, as part of 
Wisconsin's Oneida County SO2 plan for the 1971 24-hour 
SO2 NAAQS, Wisconsin issued Consent Order AM-94-38 with an 
SO2 emission limit on Ahlstrom-Munksjo's (then Rhinelander 
Paper's) coal-fired boiler, boiler B26, and EPA approved this order 
into the Wisconsin SIP on December 7, 1994. See 59 FR 63046.\13\ The 
existing SIP limit is 3.5 pounds (lbs) of SO2 per Million 
British Thermal Units (MMBTU) averaged over 24 hours (1,050 lbs per 
hour at the maximum operating

[[Page 75278]]

rate of 300 MMBTU per hour). As part of Wisconsin's Oneida County 
SO2 plan (for the 2010 SO2 NAAQS), Wisconsin 
issued Consent Order AM-15-01. AM-15-01 contains a requirement to raise 
the flue gas stack S09 height for boiler B26 to a minimum of 296 feet 
(90 meters) above ground level and establishes a more stringent 
SO2 emission limit for boiler B26 than that which is 
currently contained in the Wisconsin SIP under AM-94-38. The order 
limits boiler B26 SO2 emissions to 3.00 lbs per MMBTU on a 
24-hour basis (900 lbs per hour at the maximum operating rate) and 
limits the maximum boiler load to 300 MMBTU per hour. The order carries 
forward the SO2 emission limit, including the compliance 
demonstration and recordkeeping requirements, from AM-94-38 on boiler 
B28, which is that the sulfur content of distillate fuel fired in 
boiler B28 shall not exceed 0.05 percent by weight. In its Oneida 
County SO2 plan, Wisconsin requested that EPA approve 
Wisconsin's nonattainment plan and withdraw AM-94-38 from the Wisconsin 
SIP and replace it with AM-15-01. Given the stack height issue 
identified above, EPA cannot approve AM-15-01 into the SIP. Therefore, 
EPA is not proposing to approve AM-15-01 into the SIP, and EPA is not 
proposing to withdraw AM-94-38 from the SIP. Rather, EPA is proposing 
to approve only the following portions of AM-15-01, including the more 
stringent SO2 emission limit on boiler B26, the maximum 
boiler load limit for boiler B26, and the associated applicable 
reporting, recordkeeping, and compliance demonstration requirements 
including fuel sample collection, analysis, and retention, and 
emissions monitoring, recordkeeping, reporting, and performance testing 
requirements. Approval into the SIP would make these provisions 
permanent and federally enforceable and strengthen the Wisconsin SIP. 
Since this is not a relaxation of emissions limitations, sections 
110(l) and 193 of the CAA are satisfied and no backsliding is occurring 
as a result of this SIP revision.
---------------------------------------------------------------------------

    \13\ 59 FR 63046 references ``Rhinelander Paper'' the name and 
ownership of the facility have since changed to Ahlstrom-Munksjo.
---------------------------------------------------------------------------

    The limit in Wisconsin's 2016 plan is 3.0 lbs per MMBTU on a 24-
hour rolling average basis, which Wisconsin considers to be equivalent 
to a limit of 3.2 lbs per MMBTU on a 1-hour basis. As previously 
stated, 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. 
Although EPA is not able to approve this limit as sufficient to provide 
for attainment (since the limit does not provide for attainment without 
credit for a taller stack than has been justified under EPA's stack 
height regulations), EPA is proposing to approve the limit as SIP 
strengthening, which is appropriate for limits that improve air quality 
whether or not these limits suffice to provide for attainment in 
accordance with CAA requirements.
    EPA's 2014 SO2 Guidance discusses the option, under 
specified circumstances, for emission limits with averaging times 
greater than one hour. Wisconsin's plan relies on a limit expressed as 
a 24-hour average. A critical criterion for such limits to be used for 
attainment planning purposes is that the longer-term average limit be 
comparably stringent to the 1-hour limit that the state has 
demonstrated would provide for attainment. In this case, Wisconsin has 
not properly demonstrated what 1-hour limit would provide for 
attainment without relying on a dispersion technique, i.e. without 
relying on credit for a taller stack than is creditable under the stack 
height regulations. Therefore, it is unnecessary to evaluate whether 
the State's 24-hour average limit is comparably stringent to the 1-hour 
average. In this action, EPA is not reviewing the validity of the 
adjustment factor that Wisconsin applied to determine the 24-hour 
average limit it adopted, other than to conclude that the 24-hour 
average limit of 3.0 lbs per MMBTU that the State adopted is more 
stringent than the 24-hour average limit of 3.5 lbs per MMBTU currently 
in the SIP.

VI. Review of Other Plan Requirements

A. Emissions Inventory

    The emissions inventory and source emission rate data for an area 
serve as the foundation for air quality modeling and other analyses 
that enable states to estimate the degree to which different sources 
within a nonattainment area contribute to violations within the 
affected area and assess the expected improvement in air quality within 
the nonattainment area due to the adoption and implementation of 
control measures. The state must develop and submit to EPA a 
comprehensive, accurate, and current inventory of actual emissions from 
all sources of SO2 emissions in each nonattainment area, as 
well as any sources located outside the nonattainment area that may 
affect attainment in the area.\14\
---------------------------------------------------------------------------

    \14\ CAA section 172(c)(3).
---------------------------------------------------------------------------

    The base year inventory establishes a baseline that is used to 
evaluate emission reductions achieved by the control strategy and to 
assess RFP requirements. Wisconsin used 2011 as the base year for 
emissions inventory preparation. At the time of preparation of the 
plan, 2011 reflected the most recent emissions data available to the 
State through its annual emissions reporting requirements during 
periods with air quality violations. The emissions inventory includes 
SO2 emissions from point sources, area sources, on-road 
mobile sources, and off-road mobile sources. The point source emissions 
were compiled from Wisconsin's Air Reporting System (ARS), and the 
mobile source emissions were calculated using the MOVES2014 model. The 
point source emissions are dominated by the emissions from the 
Ahlstrom-Munksjo facility but also include a small amount of emissions 
from the Red Arrow facility. Table 1 summarizes 2011 base year 
SO2 emissions inventory data for the nonattainment area, 
categorized by emission source type (rounded to the nearest whole 
number).

  Table 1--Summary of Base Year (2011) SO2 Emissions Inventory for the
                  Oneida County SO2 Nonattainment Area
------------------------------------------------------------------------
                                                               Emissions
                           Source                                (tpy)
------------------------------------------------------------------------
Point Sources...............................................       2,430
Area Sources................................................          13
On-Road Mobile Sources......................................           3
Off-Road Mobile Sources.....................................           5
                                                             -----------
    Total...................................................       2,451
------------------------------------------------------------------------

    In addition to addressing its obligation to inventory emissions 
within the nonattainment area, Wisconsin also evaluated whether any 
point sources nearby but outside the nonattainment area might have 
significant impacts. Based on this evaluation, Wisconsin identified 
PCA, emitting about 50 tons per year and located over 30 kilometers 
from the area of concern (in neighboring Lincoln County) as warranting 
inclusion in the modeling. However, this source was not included in the 
nonattainment area inventory summarized above.
    EPA has evaluated Wisconsin's 2011 base year inventory and finds 
this inventory and the methodologies used for its development to be 
consistent with EPA guidance. As a result, EPA is proposing to 
determine that the Oneida County SO2 plan meets the 
requirements of CAA section 172(c)(3) and (4) for the Oneida County 
SO2 nonattainment area.

[[Page 75279]]

B. RACM and RACT and Enforceable Emission Limitations and Control 
Measures

    CAA section 172(c)(1) states that nonattainment plans shall provide 
for the implementation of all RACM as expeditiously as practicable 
(including such reductions in emissions from existing sources in the 
area as may be obtained through the adoption, at a minimum, of RACT) 
and shall provide for attainment of the national primary ambient air 
quality standards. CAA section 172(c)(6) requires plans to include 
enforceable emissions limitations, and such other control measures as 
may be necessary or appropriate to provide for attainment of the NAAQS. 
Because the emissions limits for the Ahlstrom-Munksjo facility provided 
in the Oneida County plan were not calculated in compliance with the 
stack height regulations, and because as a result the plan cannot be 
considered to provide an appropriate attainment demonstration, the area 
does not demonstrate RACM/RACT or meet the requirement for necessary 
emissions limitations or control measures. EPA is therefore proposing 
that the State has not satisfied the requirements in CAA sections 
172(c)(1) and (6) to adopt and submit all RACM/RACT and emissions 
limitations or control measures as needed to attain the standard as 
expeditiously as practicable.

C. Nonattainment New Source Review

    Wisconsin has a fully approved nonattainment new source review 
program. The State has implemented chapter NR 408 of the Wisconsin 
Administrative Code to satisfy the nonattainment new source review 
requirements. The program was approved by EPA into the SIP on January 
18, 1995 (60 FR 3538), and the most recent update was approved on 
November 5, 2014 (79 FR 193). NR 408 addresses nonattainment permitting 
requirements for SO2 and other pollutants. Therefore, EPA is 
proposing to affirm that the new source review requirements for the 
area have been met.

D. Reasonable Further Progress

    EPA's policy, that RFP for SO2 may be satisfied by 
adherence to an ambitious compliance schedule, is based on the fact 
that, ``for SO2 there is usually a single `step' between 
pre-control nonattainment and post-control attainment.'' \15\ In this 
instance, however, Wisconsin has not demonstrated that implementation 
of the control measures required under the plan is sufficient to 
provide for attainment of the NAAQS in the Oneida County SO2 
nonattainment area consistent with EPA requirements (in particular 
consistent with EPA regulations governing creditable stack heights). 
Since the plan does not satisfy the prerequisites for a stack height 
above formula GEP height to be creditable, and in the absence of a 
demonstration that the limit in the plan provides for attainment at the 
creditable (formula GEP) stack height, a compliance schedule to 
implement these controls is not sufficient to provide for RFP. 
Therefore, EPA proposes to conclude that the State has not satisfied 
the requirement in section 172(c)(2) to provide for RFP toward 
attainment in the Oneida County SO2 nonattainment area.
---------------------------------------------------------------------------

    \15\ 2014 SO2 Guidance, 40.
---------------------------------------------------------------------------

E. Contingency Measures

    In the Oneida County SO2 plan, Wisconsin explained its 
rationale for concluding that the plan meets the requirement for 
contingency measures. Specifically, Wisconsin relied on the 2014 
SO2 Guidance, which notes the special circumstances that 
apply to SO2 and explains on that basis why the contingency 
requirement in CAA section 172(c)(9) is met for SO2 by 
having a comprehensive program to identify sources of violations of the 
SO2 NAAQS and to undertake an aggressive follow-up for 
compliance and enforcement of applicable emission limits. Wisconsin 
stated that if SO2 attainment is not measured in the Oneida 
County SO2 attainment area, it will reevaluate the 
stationary source SO2 emission limit requirements.
    However, EPA's policy that a comprehensive enforcement program can 
satisfy the contingency measures requirement for SO2 plans 
is premised on the idea that full compliance with the controls and 
limits required in the plan will assure attainment. In this case, as 
explained above, Wisconsin's plan lacks necessary enforceable limits, 
calculated in compliance with stack height regulations, at the primary 
SO2 source in the area and therefore cannot be credited as 
demonstrating attainment with the NAAQS. Consequently, vigorous 
enforcement of the currently insufficient limits cannot be assumed to 
constitute adequate contingency measures in the face of a NAAQS 
violation. Therefore, EPA proposes that the State has not satisfied the 
requirement in section 172(c)(9) to provide for contingency measures to 
be undertaken if the area fails to make RFP or to attain NAAQS by the 
attainment date.

F. Conformity

    Generally, as set forth in section 176(c) of the CAA, conformity 
requires that actions by Federal agencies do not cause new air quality 
violations, worsen existing violations, or delay timely attainment of 
the relevant NAAQS. General conformity applies to Federal actions, 
other than certain highway and transportation projects, if the action 
takes place in a nonattainment area or maintenance area (i.e., an area 
which submitted a maintenance plan that meets the requirements of 
section 175A of the CAA and has been redesignated to attainment) for 
ozone, particulate matter, nitrogen dioxide, carbon monoxide, lead, or 
SO2. EPA's General Conformity Rule establishes the criteria 
and procedures for determining if a Federal action conforms to the 
SIP.\16\ With respect to the 2010 SO2 NAAQS, Federal 
agencies are expected to continue to estimate emissions for conformity 
analyses in the same manner as they estimated emissions for conformity 
analyses under the previous NAAQS for SO2. EPA's General 
Conformity Rule includes the basic requirement that a Federal agency's 
general conformity analysis be based on the latest and most accurate 
emission estimation techniques available.\17\ When updated and improved 
emission estimation techniques become available, EPA expects the 
Federal agency to use these techniques.
---------------------------------------------------------------------------

    \16\ 40 CFR 93.150 to 93.165.
    \17\ 40 CFR 93.159(b).
---------------------------------------------------------------------------

    Transportation conformity determinations are not required in 
SO2 nonattainment and maintenance areas. EPA concluded in 
its 1993 transportation conformity rule that highway and transit 
vehicles are not significant sources of SO2. Therefore, 
transportation plans, transportation improvement programs, and projects 
are presumed to conform to applicable implementation plans for 
SO2.\18\
---------------------------------------------------------------------------

    \18\ 58 FR 3768, 3776 (January 11, 1993).
---------------------------------------------------------------------------

VII. What action is EPA taking?

    EPA is proposing to approve the base year emissions inventory and 
to affirm that the new source review requirements for the area have 
been met. EPA is also proposing to approve the Ahlstrom-Munksjo 
SO2 emission limit as SIP strengthening. Specifically, EPA 
is proposing to approve the specific portions of Wisconsin's 
Administrative Order AM-15-01 identified above, including emission 
limits and associated compliance monitoring, recordkeeping, and 
reporting requirements. EPA is proposing to disapprove the attainment

[[Page 75280]]

demonstration, as well as the requirement for meeting RFP toward 
attainment of the NAAQS, RACM/RACT, emission limitations as necessary 
to attain the NAAQS, and contingency measures. Finalizing the proposed 
disapproval will start sanctions clocks for this area under CAA section 
179(a)-(b).

VIII. Incorporation by Reference

    In this rule, 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 only the specific portions of Wisconsin Administrative Order 
AM-15-01, effective January 15, 2016, as described in section V. above. 
EPA has made, and will continue to make, these documents generally 
available through www.regulations.gov and at EPA Region 5 Office 
(please contact the person identified in the FOR FURTHER INFORMATION 
CONTACT section of this preamble for more information).

IX. Statutory and Executive Order Reviews

    Under the CAA, the Administrator is required to approve a SIP 
submission that complies with the provisions of the CAA and applicable 
Federal regulations. 42 U.S.C. 7410(k); 40 CFR 52.02(a). Thus, in 
reviewing SIP submissions, EPA's role is to approve state choices, 
provided that they meet the criteria of the CAA. Accordingly, this 
action merely approves state law as meeting Federal requirements and 
does not impose additional requirements beyond those imposed by state 
law. For that reason, this action:
     Is not a significant regulatory action subject to review 
by the Office of Management and Budget under Executive Orders 12866 (58 
FR 51735, October 4, 1993) and 13563 (76 FR 3821, January 21, 2011);
     Is not an Executive Order 13771 (82 FR 9339, February 2, 
2017) regulatory action because it is not a significant regulatory 
action under Executive Order 12866;
     Does not impose an information collection burden under the 
provisions of the Paperwork Reduction Act (44 U.S.C. 3501 et seq.);
     Is certified as not having a significant economic impact 
on a substantial number of small entities under the Regulatory 
Flexibility Act (5 U.S.C. 601 et seq.);
     Does not contain any unfunded mandate or significantly or 
uniquely affect small governments, as described in the Unfunded 
Mandates Reform Act of 1995 (Pub. L. 104-4);
     Does not have federalism implications as specified in 
Executive Order 13132 (64 FR 43255, August 10, 1999);
     Is not an economically significant regulatory action based 
on health or safety risks subject to Executive Order 13045 (62 FR 
19885, April 23, 1997);
     Is not a significant regulatory action subject to 
Executive Order 13211 (66 FR 28355, May 22, 2001);
     Is not subject to requirements of Section 12(d) of the 
National Technology Transfer and Advancement Act of 1995 (15 U.S.C. 272 
note) because application of those requirements would be inconsistent 
with the CAA; and
     Does not provide EPA with the discretionary authority to 
address, as appropriate, disproportionate human health or environmental 
effects, using practicable and legally permissible methods, under 
Executive Order 12898 (59 FR 7629, February 16, 1994).
    In addition, the SIP is not approved to apply on any Indian 
reservation land or in any other area where EPA or an Indian tribe has 
demonstrated that a tribe has jurisdiction. In those areas of Indian 
country, the rule does not have tribal implications and will not impose 
substantial direct costs on tribal governments or preempt tribal law as 
specified by Executive Order 13175 (65 FR 67249, November 9, 2000).

List of Subjects in 40 CFR Part 52

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

    Dated: November 12, 2020.
Kurt Thiede,
Regional Administrator, Region 5.
[FR Doc. 2020-25827 Filed 11-24-20; 8:45 am]
BILLING CODE 6560-50-P


