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Federal Register / Vol. 86, No. 53 / Monday, March 22, 2021 / Rules and Regulations previously approved Arkansas interstate transport SIP submittals under CAA 110a2DiI, which established that emissions from Arkansas do not significantly contribute to nonattainment or interfere with maintenance of the 2006 24-hour or 2012 annual PM2.5 NAAQS in any other state.128 Concerning SO2 nonattainment areas in other states,129 the nearest SO2
nonattainment area to Domtar is within Titus County, Texas, approximately 100
km away. EPA designated part of Titus County, around the Monticello Power Plant, as nonattainment in Round 2 of the SO2 designations process.130 Domtar is also not near any large SO2 sources in other states. Large SO2 sources greater than 100 tpy SO2 in Oklahoma IP
Vaillant Paper Mill 100 km away and Hugo Station 119 km away and Texas Welsh Power Plant 95 km away are all approximately 100 km away from Domtar, which is too far for Domtar to contribute to air quality in those areas.
50 km is the useful distance to which AERMOD is considered accurate.
Therefore, under the Data Requirements Rule DRR, sources beyond 50 km were determined to not cause concentration gradient impacts within the area of analysis. The distance between Domtar and any of the large SO2 sources in neighboring states makes it unlikely that SO2 emissions from Arkansas interact with emissions from another state in such a way as to contribute to existing nonattainment of the 2010 one-hour SO2
NAAQS. The DRR SO2 monitor 131 for the Welsh Power Plant the closest large source to Domtar, showed attainment and characterized the air quality design value for 2017 to 2019 as 28 parts per billion ppb SO2 which is below the 2010 one-hour SO2 NAAQS of 75 ppb SO2. For these reasons, we conclude that emissions from Domtar will not adversely impact air quality in PM2.5 or
SO2 nonattainment areas in any other state.
The commenter argues that DEQ
addressed the reasonable progress requirements under 40 CFR 51.308d1
based on faulty analysis that the BART
alternative for Domtar is approvable. We addressed objections to the BART
alternative under 40 CFR 51.308e in section III.A of this final action and explained why the BART alternative provides greater reasonable progress for regional haze. We also explained how the reasonable progress requirements for regional haze under 40 CFR 51.308d1
are being met, and found that reasonable progress was not impacted by the transition from the BART FIP
requirements to the BART alternative at Domtar. Therefore, the BART alternative does not interfere with reasonable progress under the Regional Haze Rule as an other CAA requirement that could be affected under CAA 110l.
The commenter mentioned that EPAs analysis only considers regional haze and the NAAQS, and not the other CAA
requirements, for example, PSD
increments. The commenter asserts that, for this reason also, EPA fails to demonstrate that withdrawing the FIP
and approving the States SIP complies with Section 110l of the Act. EPA did not evaluate PSD increments in the proposal for two reasons: 1 Both power boilers were in operation before the major source baseline trigger dates for all three pollutants with increments SO2, NOX, and PM/PM10/PM2.5; and 2
both the FIP limits and alternative BART limits are less than past actual emissions both on an annual tons per year basis and a short-term emission rate basis, so increment around the Domtar facility was being expanded, not consumed. We noted in our proposed approval that the BART alternative emission rates were 44 percent lower for SO2 and 51 percent lower for NO2
compared to previously permitted
15127

emission rates.132 Based on this and the knowledge that the power boilers historically have operated greater than 56 percent of their permitted rates on a short term and annual basis, it can be concluded that increment was being expanded by the BART alternative. The major source baseline trigger date for PM/PM10/PM2.5 and SO2 increment was August 7, 1977. The major source baseline trigger date for NOX was February 8, 1988. Both Power Boiler No.
1 and Power Boiler No. 2 are baseline increment sources since they received permits and/or were in operation before the major source baseline date for NOX, SO2 and PM/PM10/PM2.5 increments.
PM/PM10/PM2.5, SO2, and NOX all have annual increment standards; SO2 has a three-hour and a 24-hour increment standard, and PM/PM10/PM2.5 all have 24-hour Class II increment standards.
The Air Quality Control Region AQCR
that Domtar facility is located in is AQCR 22, and the minor source baseline date for AQCR 22 was triggered for PM/
PM10/PM2.5 and SO2 by a PSD permit modification Domtar permit 287AR3
on May 31, 1983.133 134 The NOX minor source baseline date was triggered for NOX in AQCR 22 by a PSD permit modification Domtar permit 946A on August 31, 1989.135
The conversion of Power Boiler No. 1
to burn only natural gas was an increment expanding change. For the purpose of overall increment analysis, we evaluated the emissions of Power Boiler No. 1 prior to the conversion of only burning natural gas as these emissions were part of the pre-BART
baseline. As can be seen in Table 1, the annual emission limits tpy for the Arkansas BART alternative are less than the Arkansas baseline actual emissions for SO2, NOX, and PM/PM10/PM2.5.
Therefore, the Arkansas BART
alternative results in annual increment expansion for all three pollutants.

TABLE 1ANNUAL EMISSIONS ANALYSIS
Emission rates tpy Condition SO2

jbell on DSKJLSW7X2PROD with RULES

Arkansas Baseline Actual Emissions
Arkansas BART FIP
Arkansas BART Alternative
BART Alternative Reduction from Baseline Baseline Minus Alternative
128 See 78 FR 53269 August 30, 2013 regarding the 2006 24-hour PM2.5 NAAQS and 83 FR 47569
November 7, 2018 regarding the 2012 annual PM2.5 NAAQS.
129 See TSD associated with the Arkansas SO
2 transport final action 84 FR 55864 in Docket number EPAR06OAR20190438 titled, Technical Support Document Arkansas SIP
Addressing the Interstate Transport of Air Pollution
VerDate Sep<11>2014

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Requirements of CAA 110a2DiI for the 2010
Sulfur Dioxide Primary National Ambient Air Quality Standard March 2019. pages 2425
130 See 81 FR 89870.
131 Texas installed and began operation of a new, approved monitor in Titus County on December 7, 2016 to characterize air quality around the Welsh Power Plant.

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NOX

3,544
493
1,907
1,637
132 See
3,216
2,420
2,120
1,096

PM10
491
537
380
111

proposed approval notice 85 FR 14854.
AQCR Map https
www.adeq.state.ar.us/air/permits/pdfs/aqcr.pdf.
134 Arkansas Minor Source Baseline Dates https www.adeq.state.ar.us/air/permits/pdfs/
minor_source_baseline_dates.pdf.
135 Id.
133 Arkansas
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