Document ID: EPA-R07-OAR-2020-0093-0001
Agency: epa
Document Type: Proposed Rule
Title: Air Plan Approval; Iowa; Infrastructure State Implementation Plan Requirements for the 2015 Ozone National Ambient Air Quality Standard
Posted Date: 2020-03-02T05:00Z

[Federal Register Volume 85, Number 41 (Monday, March 2, 2020)]
[Proposed Rules]
[Pages 12232-12240]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2020-04229]

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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 52

[EPA-R07-OAR-2020-0093; FRL-10005-86-Region 7]

Air Plan Approval; Iowa; Infrastructure State Implementation Plan 
Requirements for the 2015 Ozone National Ambient Air Quality Standard

AGENCY: Environmental Protection Agency (EPA).

ACTION: Proposed rule.

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SUMMARY: The Environmental Protection Agency (EPA) is proposing to 
approve certain elements of a State Implementation Plan (SIP) revision 
submission from the Iowa Department of Natural Resources (IDNR) 
addressing the applicable requirements of section 110 of the Clean Air 
Act (CAA) for the 2015 Ozone National Ambient Air Quality Standards 
(NAAQS). Section

[[Page 12233]]

110 requires that each state adopt and submit a SIP revision to support 
the implementation, maintenance, and enforcement of each new or revised 
NAAQS promulgated by the EPA. These SIPs are commonly referred to as 
``infrastructure'' SIPs. The infrastructure requirements are designed 
to ensure that the structural components of each state's air quality 
management program are adequate to meet the State's responsibilities 
under the CAA. In this action, the EPA is proposing to approve the 
interstate transport portions of the State's 2015 Ozone NAAQS 
infrastructure SIP submittal.

DATES: Comments must be received on or before April 1, 2020.

ADDRESSES: You may send comments, identified by Docket ID No. EPA-R07-
OAR-2020-0093 to https://www.regulations.gov. Follow the online 
instructions for submitting comments.
    Instructions: All submissions received must include the Docket ID 
No. for this rulemaking. Comments received will be posted without 
change to https://www.regulations.gov/, including any personal 
information provided. For detailed instructions on sending comments and 
additional information on the rulemaking process, see the ``Written 
Comments'' heading of the SUPPLEMENTARY INFORMATION section of this 
document.

FOR FURTHER INFORMATION CONTACT: Lachala Kemp, Environmental Protection 
Agency, Region 7 Office, Air Quality Planning Branch, 11201 Renner 
Boulevard, Lenexa, Kansas 66219, telephone number (913) 551-7214, email 
address kemp.lachala@epa.gov.

SUPPLEMENTARY INFORMATION: Throughout this document ``we,'' ``us,'' and 
``our'' refer to the EPA.

Table of Contents

I. Written Comments
II. What is being addressed in this document?
III. Have the requirements for approval of a SIP revision been met?
IV. Background
    A. General Framework for Analyzing Interstate Transport
    B. EPA Memoranda Regarding the 2015 Ozone NAAQS
V. Iowa's SIP Submission
VI. EPA's Analysis
    A. Use of 2023 Analytic Year
    B. Selection of the 1 ppb Threshold
    1. Milwaukee Receptor
    2. Allegan Receptor
VII. What action is the EPA taking?
VIII. Statutory and Executive Order Reviews

I. Written Comments

    Submit your comments, identified by Docket ID No. EPA-R07-OAR-2020-
0093, at https://www.regulations.gov. Once submitted, comments cannot 
be edited or removed from Regulations.gov. The 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. The EPA 
will generally not consider comments or comment contents located 
outside of the primary submission (i.e., on the web, cloud, or other 
file sharing system). For additional submission methods, the full EPA 
public comment policy, information about CBI or multimedia submissions, 
and general guidance on making effective comments, please visit https://www.epa.gov/dockets/commenting-epa-dockets.

II. What is being addressed in this document?

    The EPA is proposing to approve portions of the infrastructure SIP 
submission received from the State on November 30, 2018, in accordance 
with section 110(a)(1) of the CAA. Specifically, the EPA is proposing 
to approve the following elements of section 110(a)(2)(D)(i)(I)--
significant contribution to nonattainment (prong 1), and interference 
with maintenance of the NAAQS (prong 2). The EPA will address other 
elements of section 110(a)(2) including: (A) Through (C), (D)(i)(II)--
prevention of significant deterioration of air quality (prong 3), 
(D)(ii), (E) through (H), and (J) through (M) in a separate rulemaking. 
EPA previously approved Iowa's protection of visibility (prong 4) SIP 
in a separate action. See 84 FR 66075.

III. Have the requirements for approval of a SIP revision been met?

    The submission has met the public notice requirements of 40 CFR 
51.102. The submission also satisfied the completeness criteria of 40 
CFR part 51, appendix V. The State provided a public comment period for 
the submission from September 18, 2018, to October 19, 2018. The State 
received two comments during the comment period and addressed them in 
the final SIP submission to the EPA.

IV. Background

A. General Framework for Analyzing Interstate Transport

    On October 1, 2015, the EPA promulgated a revision to the ozone 
NAAQS (2015 ozone NAAQS), lowering the level of both the primary and 
secondary standards to 0.070 parts per million (ppm).\1\ Section 
110(a)(1) of the CAA requires states to submit, within 3 years after 
promulgation of a new or revised standard, SIPs meeting the applicable 
requirements of section 110(a)(2).\2\ One of these applicable 
requirements is found in section 110(a)(2)(D)(i), otherwise known as 
the good neighbor provision, which generally requires SIPs to contain 
adequate provisions to prohibit in-state emissions activities from 
having certain adverse air quality effects on other states due to 
interstate transport of pollution. There are four so-called ``prongs'' 
within CAA section 110(a)(2)(D)(i): Section 110(a)(2)(D)(i)(I) contains 
prongs 1 and 2, while section 110(a)(2)(D)(i)(II) includes prongs 3 and 
4. This proposed action addresses the first two prongs under section 
110(a)(2)(D)(i)(I). Under prongs 1 and 2 of the good neighbor 
provision, a SIP for a new or revised NAAQS must contain adequate 
provisions prohibiting any source or other type of emissions activity 
within the State from emitting air pollutants in amounts that will 
significantly contribute to nonattainment of the NAAQS in another State 
(prong 1) or interfere with maintenance of the NAAQS in another State 
(prong 2). Under section 110(a)(2)(D)(i)(I) of the CAA, the EPA and 
states must give independent significance to prong 1 and prong 2 when 
evaluating downwind air quality problems under section 
110(a)(2)(D)(i)(I).\3\
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    \1\ National Ambient Air Quality Standards for Ozone, Final 
Rule, 80 FR 65292 (October 26, 2015). Although the level of the 
standard is specified in the units of ppm, ozone concentrations are 
also described in parts per billion (ppb). For example, 0.070 ppm is 
equivalent to 70 ppb.
    \2\ SIP revisions that are intended to meet the applicable 
requirements of section 110(a)(1) and (2) of the CAA are often 
referred to as infrastructure SIPs and the applicable elements under 
110(a)(2) are referred to as infrastructure requirements.
    \3\ See North Carolina v. EPA, 531 F.3d 896, 909-911 (2008).
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    We note that the EPA has addressed the interstate transport 
requirements of CAA section 110(a)(2)(D)(i)(I) with respect to prior 
ozone NAAQS in several regional regulatory actions, including the 2011 
Cross-State Air Pollution Rule (CSAPR), which addressed interstate 
transport with respect to the 1997 ozone NAAQS as well as the 1997 and 
2006 fine particulate matter standards, and the 2016 Cross-State Air 
Pollution Rule Update (CSAPR Update), which resolved certain good 
neighbor obligations for the 1997 ozone NAAQS

[[Page 12234]]

and partially addressed interstate transport for the 2008 ozone 
NAAQS.\4\
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    \4\ See 76 FR 48208 (August 8, 2011) (CSAPR) and 81 FR 74504 
(October 26, 2016) (CSAPR Update). As discussed later in this 
document, the D.C. Circuit Court of Appeals in Wisconsin v. EPA, 938 
F.3d 303 (D.C. Cir. 2019), remanded the rule to the extent it failed 
to eliminate states' significant contributions in accordance with 
downwind attainment dates.
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    Through the development and implementation of CSAPR, the CSAPR 
Update, and previous regional rulemakings pursuant to the good neighbor 
provision,\5\ the EPA developed the following four-step interstate 
transport framework to address the requirements of the good neighbor 
provision for the ozone NAAQS. This framework provides a reasonable and 
logical structuring of the key elements that should be considered in 
addressing the requirements of the good neighbor provision. While 
states are not mandated to follow this structure in preparing good 
neighbor SIPs, it has been upheld as a reasonable approach to address 
good neighbor requirements by various courts, including the U.S. 
Supreme Court, and the EPA generally uses the framework to evaluate 
whether state SIP submittals can be approved under the good neighbor 
provision.
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    \5\ Other regional rulemakings addressing ozone transport 
include the NOX SIP Call, 63 FR 57356 (October 27, 1998), 
and the Clean Air Interstate Rule (CAIR), 70 FR 25162 (May 12, 
2005).
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    Step 1: Identify downwind air quality problems relative to the 
ozone NAAQS. The EPA historically identified downwind areas with air 
quality problems, or receptors, using air quality modeling projections 
for a future analytic year and, where appropriate, considering 
monitored ozone data. The agency relied on modeled and monitored data 
to identify receptors expected to be in nonattainment with the ozone 
NAAQS in the future analytic year, and relied on modeled data to 
identify additional receptors that may have difficulty maintaining the 
NAAQS in the future analytic year, notwithstanding clean monitored data 
or projected attainment. These latter receptors are sometimes referred 
to as ``maintenance-only'' receptors.
    Step 2: Determine which upwind states contribute to these 
identified downwind air quality problems sufficiently to warrant 
further analysis to determine whether their emissions violate the good 
neighbor provision. These states are referred to as ``linked'' states. 
Historically, the EPA identified such upwind states as those modeled to 
impact a downwind receptor in the future analytic year at or above an 
air quality threshold equivalent to 1 percent of the ozone NAAQS. 
However, as discussed below, the EPA recognizes that there may be other 
methods of defining a ``contribution'' threshold that are reasonable 
and appropriate to apply.
    Step 3: For states linked to downwind air quality problems, 
identify upwind emissions on a statewide basis that will significantly 
contribute to nonattainment or interfere with maintenance of a standard 
at a receptor in another state. In the EPA's prior rulemakings 
addressing interstate ozone pollution transport, the agency has used 
cost-based and air quality-based criteria to evaluate regionally 
uniform NOX control strategies that were then used to 
quantify the amount of a linked upwind state's emissions, if any, that 
will significantly contribute to nonattainment or interfere with 
maintenance in another state in the future analytic year. The agency 
then established emissions budgets reflecting remaining emissions 
levels following the reduction of emissions that significantly 
contribute to nonattainment or interfere with maintenance of the NAAQS 
downwind.
    Step 4: For upwind states that are found to have emissions that 
will significantly contribute to nonattainment or interfere with 
maintenance of the NAAQS downwind, implement the necessary emissions 
reductions within the state through permanent and enforceable measures. 
In the CSAPR Update, for instance, the EPA implemented the emissions 
budgets for upwind states found to have good neighbor obligations via 
Federal Implementation Plans (FIPs) requiring certain large power 
plants in the upwind states to participate in the CSAPR NOX 
Ozone Season Group 2 Trading Program.

B. EPA Memoranda Regarding the 2015 Ozone NAAQS

    The EPA has released several documents containing information 
relevant to evaluating interstate transport with respect to the 2015 
ozone NAAQS. In these documents, the EPA made clear that the 
information provided is to assist states' efforts to develop good 
neighbor SIPs. While the information in those documents, including 
associated air quality data, could be used to inform the development of 
such SIPs, the information is not a final determination regarding 
states' obligations under the good neighbor provision.
    On January 6, 2017, the EPA published in the Federal Register a 
notice of data availability (NODA) with preliminary interstate ozone 
transport modeling with projected ozone design values for 2023, on 
which we requested comment.\6\ The EPA used the 2023 analytic year for 
this preliminary modeling because that year aligns with the 2015 ozone 
NAAQS attainment year for Moderate ozone nonattainment areas.\7\ On 
October 27, 2017, we released a memorandum (October 2017 memorandum) 
containing updated projected ozone design values for 2023, which 
incorporated changes made in response to comments on the NODA.\8\ In 
the October 2017 memorandum, we specifically stated that the updated 
2023 modeling data may be useful for states developing SIPs to address 
remaining good neighbor obligations for the 2008 ozone NAAQS. The 
October 2017 memorandum did not address the 2015 ozone NAAQS. 
Subsequently, on March 27, 2018, we issued a memorandum (March 2018 
memorandum) indicating the same 2023 projected ozone design values 
released in the October 2017 memorandum would also be useful for 
evaluating potential downwind air quality problems with respect to the 
2015 ozone NAAQS (step 1 of the four-step interstate transport 
framework). The March 2018 memorandum also included newly available 
contribution modeling results to assist states in evaluating their 
impact on projected downwind air quality problems (step 2 of the four-
step interstate transport framework).\9\
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    \6\ See Notice of Availability of the Environmental Protection 
Agency's Preliminary Interstate Ozone Transport Modeling Data for 
the 2015 Ozone National Ambient Air Quality Standard (NAAQS), 82 FR 
1733 (January 6, 2017).
    \7\ 82 FR 1735 (January 6, 2017). The basis for selection of the 
analytic year is further discussed in Section IV.A below.
    \8\ See Supplemental Information on the Interstate Transport 
State Implementation Plan Submissions for the 2008 Ozone National 
Ambient Air Quality Standards under Clean Air Act section 
110(a)(2)(D)(i)(I), October 27, 2017, available in the docket for 
this action and at https://www.epa.gov/interstate-air-pollution-transport/interstate-air-pollution-transport-memos-and-notices.
    \9\ See Information on the Interstate Transport State 
Implementation Plan Submissions for the 2015 Ozone National Ambient 
Air Quality Standards under Clean Air Act section 
110(a)(2)(D)(i)(I), March 27, 2018, available in the docket for this 
action or at https://www.epa.gov/interstate-air-pollution-transport/interstate-air-pollution-transport-memos-and-notices.
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    The March 2018 memorandum describes the methods and results of the 
updated photochemical and source-apportionment modeling used to project 
ambient ozone concentrations for the year 2023 and the state-by-state 
contributions to those concentrations. The March 2018 memorandum also 
explains that the selection of the 2023 analytic year aligns with the 
2015 ozone NAAQS attainment year for Moderate nonattainment areas. As 
described in more detail in the October 2017 and

[[Page 12235]]

March 2018 memoranda, the EPA used the Comprehensive Air Quality Model 
with Extensions (CAMx version 6.40) to model average and maximum design 
values in 2023 to identify potential nonattainment and maintenance 
receptors (i.e., monitoring sites that are projected to have problems 
attaining or maintaining the 2015 ozone NAAQS). The March 2018 
memorandum presents design values calculated in two ways: First, 
following the EPA's historical ``3 x 3'' approach \10\ for all sites, 
and second, following a modified approach for coastal monitoring sites 
in which ``overwater'' modeling data were not included in the 
calculation of future year design values (referred to as the ``no 
water'' approach).
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    \10\ See March 2018 memorandum, p. 4.
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    For purposes of identifying potential nonattainment and maintenance 
receptors in 2023 (step 1), the EPA applied the same approach used in 
the CSAPR Update, wherein the EPA considered a combination of 
monitoring data and modeling projections to identify monitoring sites 
that are projected to have problems attaining or maintaining the NAAQS. 
Specifically, the EPA identified nonattainment receptors as those 
monitoring sites with measured design values \11\ exceeding the NAAQS 
that also have projected average design values (i.e., modeled average 
2023 values) exceeding the NAAQS. The EPA identified maintenance 
receptors as those monitoring sites with projected maximum design 
values (i.e., modeled maximum 2023 values) exceeding the NAAQS. Sites 
identified as only maintenance receptors included sites with 2016 
measured design values below the NAAQS but with projected average and 
maximum design values exceeding the NAAQS and monitoring sites with 
projected average design values below the NAAQS but with projected 
maximum design values exceeding the NAAQS. The EPA included the design 
values and monitoring data for all monitoring sites projected to be 
potential nonattainment or maintenance receptors based on the updated 
2023 modeling in attachment B to the March 2018 memorandum.
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    \11\ The EPA used 2016 ozone design values, based on 2014-2016 
measured data, which were the most current data at the time of the 
analysis. See attachment B of the March 2018 memorandum, p. B-1.
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    As described further in the March 2018 memorandum, after 
identifying potential downwind nonattainment and maintenance receptors, 
the EPA next performed nationwide, state-level ozone source-
apportionment modeling to determine the expected impact from each state 
to each nonattainment and maintenance receptor in 2023.\12\ The EPA 
included contribution information resulting from the source-
apportionment modeling in attachment C to the March 2018 memorandum. 
For more specific information on the modeling and analysis, please see 
the October 2017 and March 2018 memoranda, the NODA for the preliminary 
interstate transport assessment, and the supporting technical documents 
included in the docket for this proposed action.
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    \12\ As discussed in the March 2018 memorandum, the EPA 
performed source-apportionment model runs for a modeling domain that 
covers the 48 contiguous United States and the District of Columbia, 
and adjacent portions of Canada and Mexico.
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    On August 31, 2018, the EPA issued a memorandum (the August 2018 
memorandum) providing guidance concerning potential contribution 
thresholds that may be appropriate to apply with respect to the 2015 
ozone NAAQS in step 2. Similar to the process for selecting the 1 
percent threshold for the 1997 and 2008 ozone NAAQS in CSAPR and the 
CSAPR Update, respectively, the memorandum included analytical 
information regarding the degree to which potential air quality 
thresholds would capture the collective amount of pollution transported 
from upwind states to downwind receptors for the 2015 ozone NAAQS. The 
August 2018 memorandum indicated that, based on the EPA's analysis of 
its most recent modeling data, the amount of upwind collective 
contribution captured using a 1 ppb threshold is generally comparable, 
overall (i.e., on average across all receptors), to the amount captured 
using a threshold equivalent to 1 percent of the 2015 ozone NAAQS 
(i.e., 0.70 ppb). Specifically, the data indicated that using a 1 
percent threshold captures 77 percent of the total upwind contribution 
when summed across all receptors and using a 1 ppb threshold captures 
70 percent when summed across all receptors. By contrast, using a 2 ppb 
threshold captures 55 percent of the total upwind contribution, much 
less of the total contribution summed across all receptors. 
Accordingly, the EPA indicated that it may be reasonable and 
appropriate for states to use a 1 ppb contribution threshold, as an 
alternative to the 1 percent threshold, at step 2 of the four-step 
interstate transport framework in developing their SIP revisions 
addressing the good neighbor provision for the 2015 ozone NAAQS.\13\
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    \13\ See August 2018 memorandum, p. 4.
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V. Iowa's SIP Submission

    On November 30, 2018, Iowa submitted a SIP revision addressing the 
CAA section 110(a)(2)(D)(i)(I) interstate transport requirements for 
the 2015 ozone NAAQS. Iowa chose to rely on the results of EPA's 2023 
modeling, as presented in the March 2018 memorandum, to identify 
downwind nonattainment and maintenance receptors that may be impacted 
by emissions from sources in Iowa. Based on Iowa's review of the EPA's 
modeling assumptions and model performance evaluation, Iowa determined 
that EPA's future year projections were appropriate for purposes of 
evaluating Iowa's impact on attainment and maintenance of the 2015 
ozone NAAQS in other states.
    Iowa relied on EPA's 2023 modeling to conclude that the state does 
not contribute significantly to nonattainment or interfere with 
maintenance of the 2015 ozone NAAQS in any other state. Iowa referred 
to the analytic information in EPA's August 2018 memorandum as a basis 
to use a 1 ppb contribution threshold when evaluating the state's 
contribution to downwind receptors at step 2 of EPA's four-step 
interstate transport framework. Using EPA's modeling, Iowa identified 
that it is projected to contribute below 1 percent of the 2015 ozone 
NAAQS (i.e., less than 0.70 ppb) to all but two downwind receptors: The 
nonattainment receptor in Milwaukee County, Wisconsin (Milwaukee 
receptor), and the maintenance-only receptor in Allegan County, 
Michigan (Allegan receptor). Iowa's contribution to these two receptors 
is between 1 percent and 1 ppb. Iowa concluded that 1 ppb is an 
appropriate contribution threshold to apply with respect to the 2015 
ozone NAAQS and that Iowa's emissions therefore do not contribute to 
nonattainment or maintenance problems at either receptor.
    Iowa notes that its 2023 modeled contribution to the Milwaukee 
receptor is 0.79 ppb, and its 2023 modeled contribution to the Allegan 
receptor is 0.77 ppb. Consistent with the regional analysis provided in 
the August 2018 memorandum, Iowa further notes that application of the 
1 ppb threshold captures 83 percent of the upwind contribution captured 
at the 1 percent threshold at the Milwaukee receptor and 94 percent of 
the upwind contribution captured at the 1 percent threshold at the 
Allegan receptor. Based on these data, Iowa concludes that the 1 ppb 
threshold is therefore appropriate because it captures a ``substantial 
portion'' of the transported contribution from upwind states when 
compared to the 1 percent threshold at both receptors. Because the 
state's impact on both receptors is below the 1 ppb threshold, the 
state concluded that its

[[Page 12236]]

emissions will not contribute significantly to nonattainment or 
interfere with maintenance of the 2015 ozone NAAQS in downwind states.

VI. EPA's Analysis

    The EPA proposes to approve Iowa's SIP submittal concluding that 
the State will not contribute significantly to downwind nonattainment 
or interfere with maintenance of the 2015 ozone NAAQS in other states, 
including its reliance on the information and modeling presented in 
EPA's October 2017 and 2018 memoranda. The EPA presents additional 
analysis in support of the use of the 2023 analytic year, as well as 
the State's selection of the 1 ppb contribution threshold.

A. Use of 2023 Analytic Year

    On September 13, 2019, the D.C. Circuit issued its decision in 
Wisconsin v. EPA addressing legal challenges to the CSAPR Update, in 
which the EPA partially addressed certain upwind states' good neighbor 
obligations for the 2008 ozone NAAQS. 938 F.3d 303. While the court 
generally upheld the rule as to most of the challenges raised in the 
litigation, the court remanded the CSAPR Update to the extent it failed 
to require upwind states to eliminate their significant contributions 
in accordance with the attainment dates found in CAA section 181 by 
which downwind states must come into compliance with the NAAQS. Id. at 
313. In light of the court's decision, the EPA is providing further 
explanation regarding why it proposes to find that it is appropriate 
and consistent with the statute--as well as legal precedent--to use the 
2023 analytic year for assessing good neighbor obligations for the 2015 
ozone NAAQS.
    The EPA believes that 2023 is an appropriate year for analysis of 
good neighbor obligations for the 2015 ozone NAAQS because the 2023 
ozone season is the last relevant ozone season during which achieved 
emissions reductions in linked upwind states could assist downwind 
states with meeting the August 2, 2024, Moderate area attainment date 
for the 2015 ozone NAAQS. The EPA recognizes that the attainment date 
for nonattainment areas classified as Marginal for the 2015 ozone NAAQS 
is August 2, 2021, which currently applies in several downwind 
nonattainment areas evaluated in the EPA's modeling.\14\ However, as 
explained below, the EPA does not believe that either the statute or 
applicable case law requires the evaluation of good neighbor 
obligations in a future year aligned with the attainment date for 
nonattainment areas classified as Marginal.
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    \14\ The Marginal area attainment date is not applicable for 
nonattainment areas already classified as Moderate or higher, such 
as the New York Metropolitan Area. For the status of all 
nonattainment areas under the 2015 ozone NAAQS, see U.S. EPA, 8-Hour 
Ozone (2015) Designated Area/State Information, https://www3.epa.gov/airquality/greenbook/jbtc.html (last updated Sept. 30, 
2019).
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    The good neighbor provision instructs the EPA and states to apply 
its requirements ``consistent with the provisions of'' title I of the 
CAA. CAA section 110(a)(2)(D)(i); see also North Carolina v. EPA, 531 
F.3d 896, 911-12 (D.C. Cir. 2008). This consistency instruction follows 
the requirement that plans ``contain adequate provisions prohibiting'' 
certain emissions in the good neighbor provision. As the D.C. Circuit 
held in North Carolina, and more recently in Wisconsin, the good 
neighbor provision must be applied in a manner consistent with the 
designation and planning requirements in title I that apply in downwind 
states and, in particular, the timeframe within which downwind states 
are required to implement specific emissions control measures in 
nonattainment areas and submit plans demonstrating how those areas will 
attain, relative to the applicable attainment dates. See North 
Carolina, 896 F.3d at 912 (holding that the good neighbor provision's 
reference to title I requires consideration of both procedural and 
substantive provisions in title I); Wisconsin, 938 F.3d at 313-18.
    While the EPA recognizes, as the court held in North Carolina and 
Wisconsin, that upwind emissions reduction obligations therefore must 
generally be aligned with downwind receptors' attainment dates, unique 
features of the statutory requirements associated with the Marginal 
area planning requirements and attainment date under CAA section 182 
lead the EPA to conclude that it is more reasonable and appropriate to 
require the alignment of upwind good neighbor obligations with later 
attainment dates applicable for Moderate or higher classifications. 
Under the CAA, states with areas designated nonattainment are generally 
required to submit, as part of their SIP, an ``attainment 
demonstration'' that shows, usually through air quality modeling, how 
an area will attain the NAAQS by the applicable attainment date. See 
CAA section 172(c)(1).\15\ Such plans must also include, among other 
things, the adoption of all ``reasonably available'' control measures 
on existing sources, a demonstration of ``reasonable further progress'' 
toward attainment, and contingency measures, which are specific 
controls that will take effect if the area fails to attain by its 
attainment date or fails to make reasonable further progress toward 
attainment. See, e.g., CAA section 172(c)(1); 172(c)(2); 172(c)(9). 
Ozone nonattainment areas classified as Marginal are excepted from 
these general requirements under the CAA. Unlike other areas designated 
nonattainment under the Act (including for other NAAQS pollutants), 
Marginal ozone nonattainment areas are specifically exempted from 
submitting an attainment demonstration and are not required to 
implement any specific emissions controls at existing sources to meet 
the planning requirements applicable to such areas. See CAA section 
182(a) (``The requirements of this subsection shall apply in lieu of 
any requirement that the State submit a demonstration that the 
applicable implementation plan provides for attainment of the ozone 
standard by the applicable attainment date in any Marginal Area.'') 
\16\ Marginal ozone nonattainment areas are also exempted from 
demonstrating reasonable further progress towards attainment and 
submitting contingency measures. See CAA section 182(a) (does not 
include a reasonable further progress requirement and specifically 
notes that ``Section [172(c)(9)] of this title (relating to contingency 
measures) shall not apply to Marginal Areas'').
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    \15\ Part D of title I of the Clean Air Act provides the plan 
requirements for all nonattainment areas. Subpart 1, which includes 
section 172(c), applies to all nonattainment areas. Congress 
provided in subparts 2-5 additional requirements specific to the 
various NAAQS pollutants that nonattainment areas must meet.
    \16\ States with Marginal nonattainment areas are required to 
implement new source review permitting for new and modified sources, 
but the purpose of those requirements is to ensure that potential 
emissions increases do not interfere with progress towards 
attainment, as opposed to reducing existing emissions. Moreover, the 
EPA acknowledges that states within ozone transport regions must 
implement certain emissions control measures at existing sources in 
accordance with CAA section 184, but those requirements apply 
regardless of the applicable area designation or classification.
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    Existing regulations--either local, state, or Federal--are 
typically a part of the reason why ``additional'' local controls are 
not needed to bring Marginal nonattainment areas into attainment. As 
described in the EPA's record for its final rule defining area 
classifications for the 2015 ozone NAAQS and establishing associated 
attainment dates, history has shown that the majority of areas 
classified as Marginal for prior ozone standards attained the 
respective standards by the

[[Page 12237]]

Marginal area attainment date (i.e., without being re-classified to a 
Moderate designation). 83 FR 10376 (March 9, 2018). As part of a 
historical lookback, the EPA calculated that by the relevant attainment 
date for areas classified as Marginal, 85 percent of such areas 
attained the 1979 1-hour ozone NAAQS, and 64 percent attained the 2008 
ozone NAAQS. See Response to Comments, section A.2.4.\17\ Based on 
these historical data, the EPA expects that many areas classified 
Marginal for the 2015 ozone NAAQS will also attain by the relevant 
attainment date as a result of emissions reductions that are already 
expected to occur through implementation of existing local, state, and 
federal emissions reduction programs. To the extent states have 
concerns about meeting their attainment date for a Marginal area, the 
CAA under section 181(b)(3) provides authority for them to voluntarily 
request a higher classification for individual areas, if needed.
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    \17\ Available at https://www.regulations.gov/document?D=EPA-HQ-OAR-2016-0202-0122.
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    Areas that are classified as Moderate typically have more 
pronounced air quality problems than Marginal areas or have been unable 
to attain the NAAQS under the minimal requirements that apply to 
Marginal areas. See CAA sections 181(a)(1) (classifying areas based on 
the degree of nonattainment relative to the NAAQS) and (b)(2) 
(providing for reclassification to the next highest designation upon 
failure to attain the standard by the attainment date). Thus, unlike 
Marginal areas, the statute explicitly requires a state with an ozone 
nonattainment area classified as Moderate or higher to develop an 
attainment plan demonstrating how the state will address the more 
significant air quality problem, which generally requires the 
application of various control measures to existing sources of 
emissions located in the nonattainment area. See generally CAA sections 
172(c) and 182(b)-(e).
    Given that downwind states are not required to demonstrate 
attainment by the attainment date or impose additional controls on 
existing sources in a Marginal nonattainment area, the EPA believes 
that it would be inconsistent to interpret the good neighbor provision 
as requiring the EPA to evaluate the necessity for upwind state 
emissions reductions based on air quality modeled in a future year 
aligned with the Marginal area attainment date. Rather, the EPA 
believes it is more appropriate and consistent with the nonattainment 
planning provisions in title I to evaluate downwind air quality and 
upwind state contributions, and, therefore, the necessity for upwind 
state emissions reductions, in a year aligned with an area 
classification in connection with which downwind states are also 
required to demonstrate attainment and implement controls on existing 
sources--i.e., with the Moderate area attainment date, rather than the 
Marginal area date. With respect to the 2015 ozone NAAQS, the Moderate 
area attainment date will be in the summer of 2024, and the last full 
year of monitored ozone-season data that will inform attainment 
demonstrations is, therefore, 2023.
    The EPA's interpretation of the good neighbor requirements in 
relation to the Marginal area attainment date is consistent with the 
Wisconsin opinion. For the reasons explained below, the court's holding 
does not contradict the EPA's view that 2023 is an appropriate analytic 
year in evaluating good neighbor SIPs for the 2015 ozone NAAQS. The 
court in Wisconsin was concerned that allowing upwind emissions 
reductions to be implemented after the applicable attainment date would 
require downwind states to obtain more emissions reductions than the 
Act requires of them, to make up for the absence of sufficient 
emissions reductions from upwind states. See 938 F.3d at 316. As 
discussed previously, however, this equitable concern only arises for 
nonattainment areas classified as Moderate or higher for which downwind 
states are required by the CAA to develop attainment plans securing 
reductions from existing sources and demonstrating how such areas will 
attain by the attainment date. See, e.g., CAA section 182(b)(1) & (2) 
(establishing ``reasonable further progress'' and ``reasonably 
available control technology'' requirements for Moderate nonattainment 
areas). Ozone nonattainment areas classified as Marginal are not 
required to meet these same planning requirements, and thus the 
equitable concerns raised by the Wisconsin court do not arise with 
respect to downwind areas subject to the Marginal area attainment date.
    The distinction between planning obligations for Marginal 
nonattainment areas and higher classifications was not before the court 
in Wisconsin. Rather, the court was considering whether the EPA, in 
implementing its obligation to promulgate Federal Implementation Plans 
under CAA section 110(c), was required to fully resolve good neighbor 
obligations by the 2018 Moderate area attainment date for the 2008 
ozone NAAQS. See 938 F.3d at 312-13. Although the court noted that 
petitioners had not ``forfeited'' an argument with respect to the 
Marginal area attainment date, see id. at 314, the court did not 
address whether its holding with respect to the 2018 Moderate area date 
would have applied with equal force to the Marginal area attainment 
date because that date had already passed. Thus, the court did not have 
the opportunity to consider these differential planning obligations in 
reaching its decision regarding the EPA's obligations relative to the 
then-applicable 2018 Moderate area attainment date because such 
considerations were not applicable to the case before the court.\18\ 
For the reasons discussed here, the equitable concerns supporting the 
Wisconsin court's holding as to upwind state obligations relative to 
the Moderate area attainment date also support the EPA's interpretation 
of the good neighbor provision relative to the Marginal area attainment 
date. Thus, the EPA proposes to conclude that its reliance on an 
evaluation of air quality in the 2023 analytical year for purposes of 
assessing good neighbor obligations with respect to the 2015 ozone 
NAAQS is based on a reasonable interpretation of the CAA and legal 
precedent.
---------------------------------------------------------------------------

    \18\ The D.C. Circuit, in a short judgment, subsequently vacated 
and remanded the EPA's action purporting to fully resolve good 
neighbor obligations for certain states for the 2008 ozone NAAQS, 
referred to as the CSAPR Close-Out, 83 FR 65878 (December 21, 2018). 
New York v. EPA, No. 19-1019 (D.C. Cir. October 1, 2019). That 
result necessarily followed from the Wisconsin decision, because as 
the EPA conceded, the Close-Out ``relied upon the same statutory 
interpretation of the Good Neighbor Provision'' rejected in 
Wisconsin. Id. slip op. at 3. In the Close-Out, the EPA had analyzed 
the year 2023, which was two years after the Serious area attainment 
date for the 2008 ozone NAAQS and not aligned with any attainment 
date for that NAAQS. Id. at 2. In New York, as in Wisconsin, the 
court was not faced with addressing specific issues associated with 
the unique planning requirements associated with the Marginal area 
attainment date.
---------------------------------------------------------------------------

B. Selection of the 1 ppb Threshold

    As previously discussed, the March 2018 memorandum identifies 
potential downwind nonattainment and maintenance receptors. The March 
2018 memorandum also provides state-by-state contribution data for each 
nonattainment and maintenance receptor. The EPA is proposing to rely on 
the 2023 modeling data identifying downwind receptors and upwind state 
contributions, as released in the March 2018 memorandum, to evaluate 
Iowa's good neighbor obligation with respect to the 2015 ozone NAAQS 
and to find Iowa's reliance on EPA's modeling and identification of 
receptors reasonable and approvable.
    The 2023 modeling projects that emissions from Iowa impact two

[[Page 12238]]

potential receptors (the Milwaukee nonattainment receptor and Allegan 
maintenance-only receptor) above the 1 percent threshold that the EPA 
has recently applied in CSAPR and the CSAPR Update to address the 1997 
and 2008 ozone NAAQS, respectively. However, based on the EPA's August 
2018 memorandum, Iowa provides an analysis intended to demonstrate that 
a 1 ppb contribution threshold is appropriate for analyzing its 
linkages to the identified receptors. We propose to approve the State's 
conclusion that it does not contribute to any receptors for the 
purposes of the good neighbor provision, based on the information and 
analysis provided in the State's SIP submittal and additional analysis 
as presented below.
    Consistent with the EPA's approach to both the 1997 and 2008 ozone 
NAAQS in CSAPR and the CSAPR Update described earlier, the EPA proposes 
to conclude that, at least where a state's impacts to downwind 
nonattainment and maintenance receptors are less than 1 percent of the 
NAAQS, it is reasonable to conclude that the state's impact will not 
significantly contribute to nonattainment or interfere with maintenance 
of the NAAQS at such locations. As discussed earlier, Iowa's impacts on 
all but two potential receptors identified in the March 2018 memorandum 
are below 1 percent of the 2015 ozone NAAQS. Therefore, where Iowa's 
impacts are less than 1 percent at a given receptor, the EPA proposes 
to find that this serves as a wholly sufficient basis to determine that 
the state will not significantly contribute to nonattainment or 
interfere with maintenance at that receptor for purposes of CAA section 
110(a)(2)(D)(i)(I).
    As discussed in its August 2018 memorandum, the EPA believes that 
it may be reasonable and appropriate for states to use a 1 ppb 
contribution threshold, as an alternative to a 1 percent threshold, at 
step 2 of the four-step interstate transport framework, for the 
purposes of identifying linkages to downwind receptors. In this action, 
the EPA proposes to determine, for the reasons discussed below, that it 
is appropriate to apply a 1 ppb threshold for purposes of evaluating 
upwind state linkages at the Allegan County, Michigan and Milwaukee 
County, Wisconsin receptors.
    As stated in the Iowa SIP submission, the EPA's updated 2023 
modeling discussed in the March 2018 memorandum indicates that Iowa is 
shown to have an impact below 1 percent of the 2015 ozone NAAQS to all 
but two downwind nonattainment and maintenance receptors: The 
nonattainment receptor in Milwaukee County, Wisconsin, and the 
maintenance receptor in Allegan County, Michigan, to which Iowa's 
impacts are 0.79 ppb and 0.77 ppb, respectively.\19\ These values are 
greater than 0.70 ppb (1 percent of the 2015 ozone NAAQS) and less than 
a 1 ppb threshold. Therefore further analysis is required to determine 
whether or not a 1 ppb threshold is reasonable and appropriate to apply 
as a contribution threshold for evaluation of these receptors in step 2 
of the four-step interstate transport framework.
---------------------------------------------------------------------------

    \19\ See the March 2018 memorandum, attachment C.
---------------------------------------------------------------------------

    In the August 2018 memorandum, EPA stated that the amount of upwind 
contribution captured with the 1 percent and 1 ppb thresholds is 
generally comparable, overall (i.e., on average across all receptors), 
and therefore EPA believes it may be reasonable and appropriate for 
states to use a 1 ppb contribution threshold at step 2 of the four-step 
interstate transport framework. To determine the appropriateness of 
using a 1 ppb contribution threshold for purposes of this action, the 
EPA first assessed whether the general observation in the August 2018 
memorandum that a 1 ppb threshold captures a comparable amount of 
upwind collective contribution as a 1 percent threshold holds true for 
the specific receptors at issue here. The EPA also considered the 
following additional quantitative factors to further evaluate the 
reasonableness and appropriateness of using a 1 ppb threshold at each 
receptor:
    1. How does the impact of in-state emissions on ozone levels at 
this receptor compare to collective upwind impacts?
    2. What are the impacts of individual upwind states linked at 1 ppb 
or higher to the receptor?
    3. Are individual upwind states impacting this receptor between 1 
percent and 1 ppb linked above 1 ppb to other receptors?
    For the reasons that follow, the EPA proposes to evaluate these 
factors in a weight-of-the-evidence analysis to determine whether it is 
appropriate to apply a 1 ppb threshold for the Allegan and Milwaukee 
receptors at step 2 of the four-step interstate transport framework.
    As to the first additional factor that the EPA proposes to 
consider, the magnitude of in-state emissions compared to collective 
upwind impacts at a receptor can indicate whether or not the ozone 
problem at a given receptor is largely driven by transport from upwind 
states or by in-state emissions sources. A relatively large collective 
upwind impact compared to the in-state impact at a given receptor 
indicates that the ozone problem at the receptor is driven to an 
important degree by transport from upwind states, which may support 
applying a lower threshold. Conversely, if the in-state impact far 
exceeds the collective impact from upwind states, then this comparison 
could indicate the that transport from upwind states is not an 
important part of the ozone problem at the receptor of interest, which 
may support applying a higher threshold.
    As to the second additional factor, we consider the impacts of 
individual upwind states linked at 1 ppb or more to the receptor. When 
discussing the rationale for the threshold in the August 2018 
memorandum, the EPA described that a comparable amount of emissions 
reductions from states with individual impacts below the 1 percent 
threshold would have a relatively small impact on the downwind 
receptors relative to other states with higher impacts. While greater 
than the impact of emissions reductions from states with impact below 1 
percent, the relative air quality impact of emissions reductions from 
states with contributions between 1 percent and 1 ppb could be less 
important than states with contributions higher than 1 ppb. As stated 
in the August 2018 memorandum ``the use of a 1 ppb threshold to 
identify linked upwind states still provides the potential, at step 3, 
for meaningful emissions reductions in linked upwind states in order to 
aid downwind states with attainment and maintenance of the 2015 
NAAQS.''
    As to the third additional factor, we consider whether individual 
upwind states that impact the receptor between 1 percent and 1 ppb are 
also linked to other receptor(s) at levels above 1 ppb. We would expect 
states to evaluate emissions reductions as part of a step 3 analysis in 
their SIPs regarding their contributions to the other receptor(s). Any 
resulting emissions reductions would also likely benefit the receptor 
to which the states contribute between 1 percent and 1 ppb.
    The EPA evaluated each of these factors for the two downwind 
receptors (i.e., Milwaukee and Allegan) to which Iowa's impacts are 
greater than 1 percent of the NAAQS but less than 1 ppb.
1. Milwaukee Receptor
    EPA's modeling shows the 2023 average design value at the 
Milwaukee, Wisconsin receptor is 71.2 ppb. At the Milwaukee receptor, 
the collective upwind ozone contribution captured

[[Page 12239]]

with a 1 percent threshold is 28.4 ppb and with a 1 ppb threshold it is 
23.6 ppb. Thus, a 1 ppb threshold captures 83 percent of the upwind 
contribution that would be captured using a 1 percent threshold. 
Consistent with the August 2018 memorandum, these data indicate that 
the percent of upwind contribution captured at 1 ppb is generally 
comparable to the percent captured at 1 percent of the NAAQS, 
indicating that the 1 ppb threshold may be appropriate to apply to the 
Milwaukee receptor. We therefore proceeded to further examine data 
regarding the upwind impacts at this receptor using the three 
additional weight-of-evidence factors.
    Under the first additional factor, transport of emissions from 
upwind states collectively contributes 46 percent (32.5 ppb) to the 
2023 average ozone design value as compared to a 19 percent (13.3 ppb) 
impact from in-state emissions, highlighting that both upwind and in-
state emissions have substantial impact at the Milwaukee receptor. In 
general, this factor would tend to weigh in favor of recognizing the 
importance of addressing upwind contributions at this receptor.
    Under the second factor, the EPA's analysis shows that four upwind 
states contribute above 1 ppb to the Milwaukee receptor, and as noted 
above, the collective contribution from these four states is 23.6 ppb, 
which represents 72 percent of the total contribution of all the upwind 
states. By contrast, Iowa's contribution to the Milwaukee receptor is 
0.79 ppb and represents 2 percent of the total contribution of all 
upwind states. This factor tends to support the view that a substantial 
amount of upwind contribution from states linked above 1 ppb to this 
receptor will be captured and further assessed for potential emissions 
reduction at step 3 of the interstate transport framework.
    Under the third factor, in addition to Iowa, there are five other 
upwind states that contribute between 1 percent and 1 ppb to the 
Milwaukee receptor. The collective contribution of these five 
additional states linked between 1 percent and 1 ppb is 4.1 ppb, which 
represents 12 percent of the total contribution of all the upwind 
states. Unlike Iowa, all five of these other upwind States that are 
linked between 1 percent and 1 ppb to the Milwaukee, Wisconsin receptor 
are also linked above 1 ppb to additional projected 2023 nonattainment 
or maintenance receptors. Thus, even though we would not expect these 
States to make emissions reductions to address the Milwaukee receptor 
if a 1 ppb threshold is applied, we do expect these States to evaluate 
their potential for additional emissions reductions to address their 
linkage to other receptors, which would also provide co-benefits to the 
Milwaukee receptor.
    Based on this analysis, EPA finds that for the Milwaukee, Wisconsin 
receptor, a vast majority (85 percent) of the upwind states' emissions 
will be captured for further evaluation for possible control at step 3 
of the four-step interstate transport framework from states which 
contribute above the 1 ppb threshold to this receptor or from states 
which contribute between 1 percent and 1 ppb to the Milwaukee receptor 
and above 1 ppb to at least one other receptor. This demonstrates that 
for the Milwaukee receptor, the effect of applying a 1 ppb threshold 
rather than a 1 percent threshold is likely less consequential than if 
a major share of contribution from upwind states contributing between 1 
percent and 1 ppb to the Milwaukee receptor did not contribute above 1 
ppb to any other receptor.
    Given the technical information and analysis discussed above, the 
EPA finds that Iowa's use of the 1 ppb contribution threshold is 
reasonable and appropriate to support the conclusion that it will not 
contribute to the Milwaukee, Wisconsin nonattainment receptor.
2. Allegan Receptor
    In assessing Iowa's conclusions as to the Allegan, Michigan 
receptor, the EPA applied the weight-of-evidence analysis identified 
above, again using the 2023 contribution data. EPA's modeling shows 
that the 2023 average design value at the Allegan, Michigan receptor is 
69.0 ppb. The upwind ozone collectively captured at Allegan, Michigan 
is 38.8 ppb and 36.6 ppb, respectively for the 1 percent and 1 ppb 
contribution thresholds, which indicates that a 1 ppb threshold 
captures nearly all (i.e., 94 percent) of the amount of contribution 
captured using a 1 percent threshold. The August 2018 memorandum states 
that if the amount captured at 1 ppb is generally comparable to the 
amount captured at 1 percent of the NAAQS, then the 1 ppb threshold may 
be appropriate. The EPA proposes to find that the amounts captured by 
the two thresholds for the Allegan receptor are comparable. We 
therefore proceeded to further examine the receptor using the three 
additional weight of evidence factors.
    Under the first factor, transport of emissions from upwind states 
collectively contribute 62 percent to the 2023 average ozone design 
value compared to a 5 percent contribution from in-state emissions, 
highlighting that upwind emissions have a large impact at the Allegan, 
Michigan receptor. In general, this factor would tend to weigh in favor 
of recognizing the importance of upwind contributions at this receptor.
    Under the second factor, seven upwind states contribute above 1 ppb 
to the Allegan, Michigan receptor, and as noted above the collective 
impact from these states is 36.6 ppb, which represents 85 percent of 
the total impact of all the upwind states. By contrast, Iowa's 
contribution to Allegan, Michigan is 0.77 ppb and represents 2 percent 
of the total contribution of all upwind states. This factor strongly 
supports the view that a substantial amount of upwind contribution will 
be captured by states linked above 1 ppb to this receptor and further 
assessed for potential emissions reduction at step 3 of the interstate 
transport framework.
    Under the third factor, in addition to Iowa, there are two other 
upwind states that contribute between 1 percent and 1 ppb to Allegan, 
Michigan. The collective contribution of these two states linked 
between 1 percent and 1 ppb is 1.4 ppb and this represents 3 percent of 
the total contribution of all the upwind states. One of the two 
additional states linked between 1 percent and 1 ppb to the Allegan, 
Michigan receptor is also linked above 1 ppb to other 2023 
nonattainment or maintenance receptors. Thus, even though we would not 
expect this State to make emissions reductions to address the Allegan 
receptor if a 1 ppb threshold is applied, we do expect this State to 
evaluate its potential for additional emissions reductions due to its 
linkage to other receptors, which would also provide co-benefits to the 
Allegan receptor.
    Based on this analysis, the EPA finds that for the Allegan, 
Michigan receptor, a vast majority (85 percent) of the contribution 
from upwind states will be captured using a 1 ppb threshold. Emissions 
in the upwind states that contribute above 1 ppb to this receptor or 
which contribute between 1 percent and 1 ppb to the Allegan receptor 
and above 1 ppb to at least one other receptor will be evaluated for 
possible control at step 3. The analysis presented here demonstrates 
that the effect of applying a 1 ppb threshold rather than a 1 percent 
threshold to the Allegan receptor is likely less consequential than if 
a major share of the total upwind contribution to the receptor came 
from states contributing between 1 percent and 1 ppb to the Milwaukee 
receptor and not contributing above 1 ppb to any other receptor.

[[Page 12240]]

    Given the technical information and analysis discussed above, EPA 
finds that the state of Iowa's use of the 1 ppb contribution threshold 
is reasonable and appropriate to support the conclusion that it will 
not contribute to the Allegan, Michigan maintenance receptor.

VII. What action is the EPA taking?

    The EPA is proposing to approve Iowa's November 30, 2018, 
submission addressing certain infrastructure elements for the 2015 
ozone NAAQS. Specifically, the EPA is proposing to approve the 
following elements of CAA section 110(a)(2)(D)(i)(I)--significant 
contribution to nonattainment of the NAAQS (prong 1) and interference 
with maintenance of the NAAQS (prong 2). The EPA is processing this as 
a proposed action because it is soliciting comments. Final rulemaking 
will occur after consideration of any comments.

VII. 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 review state choices, and 
approve them if they meet the criteria and requirements of the CAA. 
Accordingly, this action merely approves state law as meeting Federal 
requirements and does not impose additional requirements beyond those 
imposed by state law. For that reason, this action:
     Is not a significant regulatory action subject to review 
by the Office of Management and Budget under Executive Orders 12866 (58 
FR 51735, October 4, 1993) and 13563 (76 FR 3821, January 21, 2011);
     Is not an Executive Order 13771 (82 FR 9339, February 2, 
2017) regulatory action because SIP approvals are exempted under 
Executive Order 12866.
     Does not impose an information collection burden under the 
provisions of the Paperwork Reduction Act (44 U.S.C. 3501 et seq.);
     Is certified as not having a significant economic impact 
on a substantial number of small entities under the Regulatory 
Flexibility Act (5 U.S.C. 601 et seq.);
     Does not contain any unfunded mandate or significantly or 
uniquely affect small governments, as described in the Unfunded 
Mandates Reform Act of 1995 (Pub. L. 104-4);
     Does not have Federalism implications as specified in 
Executive Order 13132 (64 FR 43255, August 10, 1999);
     Is not an economically significant regulatory action based 
on health or safety risks subject to Executive Order 13045 (62 FR 
19885, April 23, 1997);
     Is not a significant regulatory action subject to 
Executive Order 13211 (66 FR 28355, May 22, 2001);
     Is not subject to requirements of the National Technology 
Transfer and Advancement Act (NTTA) because this rulemaking does not 
involve technical standards; 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).
    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, Air quality 
control region, Incorporation by reference, Infrastructure, 
Intergovernmental relations, Ozone, Reporting and record-keeping.

    Dated: February 25, 2020.
James Gulliford,
Regional Administrator, Region 7.

    For the reasons stated in the preamble, the EPA proposes to amend 
40 CFR part 52 as set forth below:

PART 52--APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS

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

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

Subpart Q--Iowa

0
2. In Sec.  52.820, the table in paragraph (e) is amended by adding the 
entry ``(53)'' in numerical order to read as follows:

Sec.  52.820  Identification of plan.

* * * * *
    (e) * * *

                                   EPA-Approved Iowa Nonregulatory Provisions
----------------------------------------------------------------------------------------------------------------
   Name of nonregulatory SIP     Applicable geographic or        State
           provision                nonattainment area      submittal date  EPA approval date     Explanation
----------------------------------------------------------------------------------------------------------------
 
                                                  * * * * * * *
(53) Section 110(a)(2)          Statewide.................      11/30/2018  [Date of           This action
 (D)(i)(I)--significant                                                      publication of     approves the
 contribution to nonattainment                                               the final rule     following CAA
 (prong 1), and interfering                                                  in the Federal     elements:
 with maintenance of the NAAQs                                               Register],         110(a)(1) and
 (prong 2) (Interstate                                                       [Federal           110(a)(2
 Transport) Infrastructure                                                   Register           (D)(i)(I)--prong
 Requirements for the 2015                                                   citation of the    s 1 and 2. [EPA-
 Ozone (O3) NAAQS.                                                           final rule].       R07-OAR-2020-009
                                                                                                3; FRL-10005-86-
                                                                                                Region 7].
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[FR Doc. 2020-04229 Filed 2-28-20; 8:45 am]
 BILLING CODE 6560-50-P