Federal Register / Vol. 86, No. 122 / Tuesday, June 29, 2021 / Proposed Rules 34187 

1Additionally, TCEQ submitted a petition for 

reconsideration on December 11, 2017, and on 

December 19, 2017, Vistra Energy provided 

additional information regarding facility 

retirements and the deployment of additional SO2

monitors to support its February 2017 petition for 

reconsideration and administrative stay. 

2https://www.epa.gov/sites/production/files/ 

2018-09/documents/3143_signed_response.pdf. 

3The EPA recently found that Texas has failed to 

submit State Implementation Plans to satisfy certain 

nonattainment planning requirements of the CAA 

for portions of Freestone and Anderson Counties, 

Rusk and Panola Counties, and Titus County. See 

85 FR 48111. 

4Additionally, as detailed in a separate document 

published elsewhere in this issue of the Federal 

Register that has been signed concurrently along 

with this withdrawal notice, the EPA is also now 

denying the administrative petitions from Vistra 

Energy and TCEQ. See https://www.regulations.gov 

under Docket ID No. EPA–HQ–OAR–2014–0464. 

* * * * * 

[FR Doc. 2021–13693 Filed 6–28–21; 8:45 am] 

BILLING CODE 6560–50–P 

ENVIRONMENTAL PROTECTION 

AGENCY 

40 CFR Part 81 

[EPA–HQ–OAR–2014–0464; FRL–10024–28– 

OAR] 

Error Correction of the Area 

Designations for the 2010 1-Hour 

Sulfur Dioxide (SO2) Primary National 

Ambient Air Quality Standard (NAAQS) 

in Freestone and Anderson Counties, 

Rusk and Panola Counties, and Titus 

County in Texas 

AGENCY: Environmental Protection 

Agency (EPA). 

ACTION: Proposed rule; withdrawal. 

SUMMARY: The Environmental Protection 

Agency (EPA) is withdrawing its August 

22, 2019, proposed rule, which 

proposed both to determine that the 

EPA made an error in the area 

designations for the 2010 Sulfur Dioxide 

(SO2) Primary National Ambient Air 

Quality Standard (NAAQS) for portions 

of Freestone and Anderson Counties, 

Rusk and Panola Counties, and Titus 

County in Texas, and to correct the 

proposed error by modifying the 

designations of those areas to 

unclassifiable. The EPA is withdrawing 

the proposed rule because the EPA, 

informed in part by technical 

information received during the public 

comment period on the proposed rule 

that further supports the EPA’s initial 

designations of these areas, no longer 

believes the bases identified in the 

proposed error correction support the 

proposed conclusion that an error 

correction is appropriate. 

DATES: As of June 29, 2021, the 

proposed rule published at 84 FR 43757 

on August 22, 2019, is withdrawn. 

FOR FURTHER INFORMATION CONTACT: 

Corey Mocka, U.S. Environmental 

Protection Agency, Office of Air Quality 

Planning and Standards, Air Quality 

Policy Division, 109 T.W. Alexander 

Drive, Mail Code C539–04, Research 

Triangle Park, NC 27711; phone 

number: (919) 541–5142; email address: 

mocka.corey@epa.gov. 

SUPPLEMENTARY INFORMATION: 

I. Background 

On December 13, 2016, the EPA 

designated portions of Freestone and 

Anderson Counties, Rusk and Panola 

Counties, and Titus County in Texas as 

nonattainment for the 2010 1-hour 

primary SO2 NAAQS (81 FR 89870, 

codified at 40 CFR 81.344) (‘‘Round 2 

Supplement’’). On February 13, 2017, 

Vistra Energy, which owns SO2

emissions sources in each of the three 

areas, sent the EPA a petition for 

reconsideration, purportedly pursuant 

to Clean Air Act (CAA) section 

307(d)(7)(B) and the Administrative 

Procedure Act 5 U.S.C. 553(e), and for 

administrative stay of the EPA’s 

nonattainment designations for portions 

of Freestone and Anderson Counties 

(‘‘Big Brown Steam Electric Station 

area’’), Rusk and Panola Counties 

(‘‘Martin Lake Electrical Station area’’), 

and Titus County (‘‘Monticello Steam 

Electric Station area’’). On March 15, 

2017, the Texas Commission on 

Environmental Quality (TCEQ) also 

submitted a request for an 

administrative stay of the Round 2 

Supplement final designations for these 

areas in Texas.1 On September 21, 2017, 

the EPA initially responded to Vistra 

Energy’s February 2017 petition for 

reconsideration by indicating an intent 

to undertake an administrative action 

with notice and comment to revisit the 

nonattainment designations for the three 

areas, but explained that pending 

completion of such action, the 

nonattainment designations remained in 

effect.2 3

The EPA published a proposed rule in 

the Federal Register on August 22, 

2019, titled ‘‘Error Correction of the 

Area Designations for the 2010 1-Hour 

Sulfur Dioxide (SO2) Primary National 

Ambient Air Quality Standard (NAAQS) 

in Freestone and Anderson Counties, 

Rusk and Panola Counties, and Titus 

County in Texas’’ (84 FR 43757) 

(‘‘Proposed Error Correction’’). Under 

the EPA’s CAA authority at section 

110(k)(6) to correct errors in acting on 

state implementation plans (SIPs) or in 

issuing designations, redesignations, 

classifications or reclassifications, the 

EPA proposed that in designating these 

areas as nonattainment under CAA 

sections 107(d)(1)(A)(i), (d)(1)(B)(ii), and 

(d)(2)(A), it erred in not giving greater 

weight to Texas’s preference to 

characterize air quality through 

monitoring, and to steps undertaken by 

Texas to begin monitoring in these three 

areas, when considering all available 

information; in relying on available air 

quality analyses in making the initial 

designations that the EPA recognized 

included certain limitations; or a 

combination of these two issues. 

Therefore, to correct these proposed 

errors, the EPA also proposed that the 

previously designated nonattainment 

areas in Freestone and Anderson 

Counties, Rusk and Panola Counties, 

and Titus County in Texas each be 

revised to reflect an unclassifiable 

designation under CAA section 

107(d)(1)(A)(iii). The EPA has not 

finalized the Proposed Error Correction 

and is not doing so in this action. 

Instead, the EPA is now withdrawing 

the Proposed Error Correction.4

II. Reasons for Withdrawing the 

Proposed Error Correction 

A. Additional Air Quality Modeling 

In the Proposed Error Correction, the 

EPA proposed that it erred in relying on 

available air quality modeling submitted 

by Sierra Club in making the initial 

nonattainment designations for these 

three areas. The EPA explained in the 

proposed action that the modeling 

submitted by Sierra Club (‘‘December 

2015’’ and ‘‘March 2016’’ modeling), 

which purported to show 

nonattainment, was developed in 

accordance with the general 

recommendations on modeling 

provided by the EPA but stated that the 

modeling contained ‘‘key limitations 

and uncertainties.’’ We made this 

statement in the Proposed Error 

Correction despite also acknowledging 

that we had explained in the record for 

the Round 2 Supplement that 

individually these key limitations and 

uncertainties would not significantly 

change modeled results or, in many 

cases, could result in underestimation of 

SO2 concentrations. In the Proposed 

Error Correction, the EPA also stated 

that given the possible collective 

significance of these issues and, in the 

case of the areas around the Martin Lake 

and Monticello facilities, given that the 

maximum modeled concentrations are 

within about 10 percent of the 2010 SO2

NAAQS, we were less confident in our 

prior statements that potential 

adjustments to the Sierra Club modeling 

would not result in modeled values near 


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34188 Federal Register / Vol. 86, No. 122 / Tuesday, June 29, 2021 / Proposed Rules 

5As explained in the EPA’s final designations 

Technical Support Document (TSD), the modeled 

99th percentile daily maximum 1-hour SO2

concentrations for the Martin Lake and Monticello 

facilities are 14 percent and 8 percent above the 

2010 SO2 NAAQS, respectively. 

6See pages 27–29, 48–50, and 75–77 of the EPA’s 

final designations TSD, available in the public 

docket and at https://www.epa.gov/sites/ 

production/files/2016-11/documents/texas_4_

deferred_luminant_tsd_final_docket.pdf. 

7See https://www.regulations.gov under Docket 

ID No. EPA–HQ–OAR–2014–0464. 

or below the NAAQS.5 Additionally, the 

EPA stated in the Proposed Error 

Correction that while individually these 

deficiencies are not dispositive, 

collectively they are a sufficient basis 

for the EPA to propose that we erred in 

relying on the Sierra Club modeling in 

making the initial nonattainment 

designations for the three Texas areas. 

The EPA received several comments 

on the Proposed Error Correction. Sierra 

Club submitted a comment on the 

Proposed Error Correction that included 

updated modeling (‘‘September 2019 

modeling’’). Sierra Club’s updated 

September 2019 modeling addressed all 

aspects of the March 2016 modeling that 

the EPA had identified in the Proposed 

Error Correction as a limitation or 

uncertainty. The September 2019 

modeling purported to demonstrate that 

the Martin Lake Electrical Station area 

did not meet the 2010 SO2 NAAQS at 

the time of designation in the Round 2 

Supplement (i.e., December 2016), and 

also currently does not meet the 2010 

SO2 NAAQS based on more recent data. 

Sierra Club did not submit updated 

modeling for the Big Brown and 

Monticello areas as part of its September 

2019 comment submission, but rather 

asserted that the EPA’s previously 

identified limitations (individually or 

collectively) have no material effect on 

the model results for those areas in the 

same way as they demonstrated with the 

Martin Lake area’s modeling. 

The EPA also notes, upon re-review of 

the Proposed Error Correction and 

Round 2 Supplement, that we did not 

acknowledge in the Proposed Error 

Correction that we actually considered 

the collective impact of all these same 

aspects of the modeling in the record for 

the Round 2 Supplement (to the extent 

those aspects remained in the March 

2016 modeling relied on in the Round 

2 Supplement).6 In the Proposed Error 

Correction, we also did not explain any 

change in our thinking from our 

assessment of the collective impact in 

the Round 2 Supplement’s record. 

As explained further in the technical 

support document for this withdrawal, 

the EPA has assessed Sierra Club’s 

September 2019 modeling submitted 

during the Proposed Error Correction 

public comment period.7 This 

assessment supports the EPA’s previous 

reliance on the March 2016 modeling as 

the basis for its final nonattainment 

designation for the Martin Lake area in 

the Round 2 Supplement. Based on 

consideration of that information 

submitted by commenters and on 

further consideration of the entirety of 

our record for the Round 2 Supplement, 

the EPA now has concerns with the 

accuracy of the Proposed Error 

Correction’s characterization of the 

March 2016 modeling and no longer 

believes that this proposed basis 

supports the proposed conclusion that 

an error correction is appropriate or that 

reliance on such information for the 

nonattainment designation was in error. 

The refined modeling submitted on the 

Proposed Error Correction demonstrates 

that the EPA’s Round 2 Supplement 

assessment of the impact of further 

refining the March 2016 modeling was 

reasonable and correct, that such 

refinement would not alter the 

conclusion that the Martin Lake area 

was not attaining the NAAQS at the 

time of the Round 2 Supplement. 

Overall, the EPA’s assessment of the 

information and of our record for the 

Round 2 Supplement for all three areas 

is that refinement of the aspects of the 

modeling the EPA identified in the 

Proposed Error Correction would not 

alter the EPA’s nonattainment 

designations for any of the three 

nonattainment area designations in the 

Round 2 Supplement, and that the 

submitted information further confirms 

our Round 2 Supplement analysis of 

then-available data. 

B. Comments on Texas’s Monitoring 

Preference 

In the Proposed Error Correction, the 

EPA also proposed that when we 

considered all available information at 

the time of designation, we erred in 

failing to give ‘‘greater’’ weight to the 

State of Texas’ preference to use 

ambient air monitors to characterize SO2

air quality in their state for purposes of 

the designation. We proposed this 

despite also acknowledging in the 

proposal that because these areas 

(around certain SO2 emissions sources) 

were subject to the Round 2 deadline of 

July 2, 2016, these areas were required 

to be designated at that time based on 

the EPA’s assessment of available 

information even though the State of 

Texas stated a preference to later 

characterize the areas based on future 

monitoring data and its intention to 

install monitors for these areas. 

In addition to the modeling submitted 

during the public comment period for 

the Proposed Error Correction, the 

Sierra Club also commented that the 

EPA was required to designate the three 

areas in Texas by the court-ordered 

deadline based on the information 

available at that time (i.e., Sierra Club’s 

December 2015 and March 2016 

modeling). Because monitoring 

information was not available in 2016 

for the Martin Lake, Big Brown, or 

Monticello areas, the Sierra Club stated 

that monitoring data consequently could 

not inform the EPA’s designations 

decisions. The Environmental 

Protection Network (EPN) submitted a 

similar comment claiming that the EPA 

did not have the discretion to delay 

designations for these three areas in 

Texas under the applicable courtordered deadline and that the EPA was 

required to designate the areas based on 

the best available data at the time of the 

designations. Additionally, EPN 

asserted that Texas’s preference for 

future air quality monitoring did not 

undermine the available modeling data 

demonstrating that the areas were 

violating the 2010 SO2 NAAQS. 

In light of the comments submitted on 

the Proposed Error Correction, and the 

absence of a clearly identified error in 

the Round 2 Supplement, the EPA no 

longer believes that this proposed basis 

supports the proposed conclusion that 

an error correction is appropriate and no 

longer believes that we failed to give the 

appropriate weight to the State’s 

preference for future monitoring 

information when we considered all 

available information at the time of the 

Round 2 Supplement. For the reasons 

discussed below, the EPA has concerns 

with the prior proposed assertion that 

the EPA was in error for not giving 

greater weight to the state’s preference 

for future monitoring information in the 

absence of any available monitoring 

data at that time, let alone over reliance 

on then-available air quality modeling 

to assess SO2 air quality. Given that the 

Proposed Error Correction’s basis was 

predicated on the EPA relying on or 

weighing more heavily a preference for 

information that was not available at the 

time the EPA was required to finalize 

the Round 2 Supplement, the EPA no 

longer believes such a basis provides 

substantial support for the argument 

that the Round 2 Supplement should be 

revised. 

CAA section 107(d) specifies that the 

EPA make designations based on the air 

quality at the time of final designations 

(i.e., determining at the time of signature 

whether the area meets the NAAQS) and 

consider all available information on air 

quality at that time. In other words, the 


lotter on DSK11XQN23PROD with PROPOSALS1
Federal Register / Vol. 86, No. 122 / Tuesday, June 29, 2021 / Proposed Rules 34189 

8See Miss. Comm’n on Envtl. Quality v. EPA, 790 

F.3d 138, 156 (D.C. Cir. 2015); Catawba County v. 

EPA, 571 F.3d 20, 43–44 (D.C. Cir. 2009). The 2015 

decision upheld the EPA’s designations issued just 

days before new certified air quality data became 

available showing more areas violating the 2008 

ozone NAAQS than the EPA designated as 

nonattainment. See also State of Texas v. EPA, 983 

F.3d 826, 837–838 (5th Cir. 2020) (holding that the 

EPA’s nonattainment designation, which modified 

the state’s recommendation, was not arbitrary and 

capricious because the county was not compliant 

with the ozone NAAQS when the EPA promulgated 

its designation and the CAA uses concrete terms 

such that a county either does or does not meet the 

NAAQS). 

9Round 2 Supplement Reponses to Comments, 

Page 13. Available in the public docket and at 

https://www.epa.gov/sites/production/files/2016- 

11/documents/rtc_so2_comments_received_

document_4_tx_sources_final_0.pdf. 

10As explained in the EPA’s intended and final 

designations TSDs and the responses to comments 

document that accompanied the Round 2 

Supplement, at the time of the EPA’s final 

designations on December 13, 2016, there were no 

SO2 monitors sited in the areas of maximum 

concentration to properly characterize the air 

quality around the Martin Lake, Big Brown, or 

Monticello areas, nor were there SO2 monitors in 

the same counties as the facilities. 

11The EPA received a comment from the Utility 

Air Regulatory Group on the Round 2 Supplement 

suggesting that the EPA wait for the future 

completion of three years of monitoring before 

designating certain Round 2 areas. In the Round 2 

Supplement Responses to Comments (page 14), the 

EPA responded that the Agency does not have the 

discretion to await the results of future monitoring 

because of the court order to designate certain areas 

by the July 2, 2016, deadline. 

12See State of Texas v. EPA, 983 F.3d 826, 836– 

838 (5th Cir. 2020). 

EPA does not interpret the statute as 

allowing the EPA to consider future air 

quality in the initial designations 

process, and the D.C. Circuit has upheld 

this interpretation as reasonable.8 The 

record for the Round 2 Supplement 

explains, and the EPA maintains, that 

both air quality modeling and ambient 

monitoring are appropriate tools for 

characterizing ambient air quality for 

purposes of informing decisions to 

implement the SO2 NAAQS, including 

designation determinations.9 The EPA’s 

reliance on modeling to assess SO2 air 

quality, even in the face of conflicting 

monitoring, where appropriate, has been 

judicially affirmed. See, e.g., Montana 

Sulphur & Chemical Company v. EPA, 

666 F.3d 1174, 1185 (9th Cir. 2012). 

In the Round 2 Supplement for these 

three areas, the EPA considered Texas’s 

recommendations but appropriately 

modified the recommendations, per 

CAA section 107(d)(1)(B)(2), because 

they were not supported by currently 

available information. Specifically, the 

EPA’s assessment of Sierra Club’s 

modeling was that currently available 

information showed violations of the 

2010 SO2 NAAQS. At the time of the 

EPA’s final nonattainment designations 

for portions of Freestone and Anderson 

Counties, Rusk and Panola Counties, 

and Titus County, although Texas 

preferred that the EPA designate the 

areas based on proposed future 

monitoring data rather than on existing 

submitted modeling, there were no 

representative monitoring data 10 or 

other reliable modeling demonstrations 

available to refute Sierra Club’s 

information demonstrating violations of 

the 2010 SO2 NAAQS, as explained in 

the EPA’s final designations TSD.11 The 

absence of available monitoring data at 

that time did not relieve the EPA of its 

obligation to issue designations for these 

areas by the court-ordered deadline. 

Furthermore, at the time of the final 

designations, the Agency did not have 

the discretion to await the results of 3 

years of ambient air monitoring data 

(i.e., 2018–2020) from Texas’s proposed 

(but not yet established) monitoring 

sites before taking final action due to the 

court’s order to designate certain areas 

in Texas. There was, however, as 

explained previously and in the EPA’s 

final designations TSD, valid modeling 

submitted by the Sierra Club based on 

the then-most recent actual emissions 

demonstrating that the areas were 

violating the 2010 SO2 NAAQS. As 

explained earlier, the EPA no longer 

believes there were errors in our Round 

2 Supplement’s analysis that Sierra Club 

submitted valid, representative 

modeling (based on the then-most 

recent actual SO2 emissions) that 

demonstrated that the areas were 

violating the 2010 SO2 NAAQS, or that 

further refining the modeling would 

result in modeled values near or below 

the standard. Therefore, even though the 

EPA considered Texas’s preference for 

monitoring, given that the statute 

requires that the EPA consider available 

information, Texas’s preference for 

reliance on monitoring information 

when there were no such monitoring 

data available at the time of the EPA’s 

final designations in December 2016 did 

not and could not rebut Sierra Club’s 

modeling showing violations of the 

2010 SO2 NAAQS.12

III. Purpose of This Action 

In the 2019 Proposed Error 

Correction, the EPA proposed that our 

relying on the Sierra Club modeling 

along with our not giving greater weight 

to Texas’ preference for monitoring, 

represented an insufficient basis for the 

EPA’s initial nonattainment 

designations. For the reasons discussed 

previously, the EPA no longer believes 

it has a basis under these reasons 

individually or collectively to propose 

to or conclude that we made errors in 

our nonattainment designations of these 

areas, and, therefore, no longer believes 

that we have a basis to conclude that the 

EPA could not determine, based on 

available information at the time of 

issuing the designation, whether the 

three Texas areas that are the subject of 

this proposed action were meeting or 

not meeting the 2010 SO2 NAAQS (i.e., 

the conclusion necessary to correct the 

designations to unclassifiable). 

Therefore, the EPA is withdrawing the 

Proposed Error Correction. 

IV. Statutory and Executive Order 

Reviews 

This withdrawal of a proposed rule 

does not establish new regulatory 

requirements. Hence, the requirements 

of other regulatory statutes and 

Executive Orders that generally apply to 

rulemakings (e.g., the Regulatory 

Flexibility Act) do not apply to this 

action. 

List of Subjects in 40 CFR Part 81 

Environmental protection, Air 

pollution control, Sulfur dioxide. 

Michael S. Regan, 

Administrator. 

[FR Doc. 2021–13696 Filed 6–28–21; 8:45 am] 

BILLING CODE 6560–50–P 

ENVIRONMENTAL PROTECTION 

AGENCY 

40 CFR Parts 1036 and 1037 

[EPA–HQ–OAR–2019–0307; FRL–10018–51– 

OAR] 

Improvements for Heavy-Duty Engine 

and Vehicle Test Procedures 

AGENCY: Environmental Protection 

Agency (EPA). 

ACTION: Notice of proposed rulemaking. 

SUMMARY: This notice of proposed 

rulemaking includes corrections, 

clarifications, additional flexibilities, 

and adjustment factors to improve the 

Greenhouse gas Emissions Model (GEM) 

compliance tool for heavy-duty vehicles 

while more closely matching the 

outputs produced by the original GEM 

version 3.0 that was used to establish 

the CO2 standards for Model Years 2021 

and later in the 2016 Heavy-duty Phase 

2 final rule. This document 

supplements the proposed rule 

published on May 12, 2020, which 

included a larger set of proposed 

revisions to modify and improve GEM. 

Most of the proposed revisions from that 

notice of proposed rulemaking are 

addressed in a final rulemaking 

published elsewhere in the Final Rules 

section of this issue of the Federal 

Register. Given the nature of this 

proposal, there will be neither 


lotter on DSK11XQN23PROD with PROPOSALS1