AQ_F_0900009_20210629_CMPL_CmplDetLtr

ROY COOPER
Governor o
2'
JOHN NICHOLSON interim Secretary
MICHAELABRACZINSKAS NORTH CAROLINA
Director Environmental Quality
June 29, 2021
Ms.Dawn Hughes,Plant Manager
The Chemours Company FC,LLC
Fayetteville Works
22828 NC Hwy 87 West
Fayetteville,North Carolina 28306-7332
Subject: Emissions Estimation Technique for Plant-Wide C3 I1FPO Dimer Acid
The Chemours Company,Fayetteville, Bladen County,North Carolina
Facility ID No. 0900009,Permit No. 03735T48
Dear Ms. Hughes,
Recent performance testing at your facility in March of 2021 has revealed an issue associated with the
procedures and use of performance testing results for emission estimation in the periods between the
periodic performance tests. The procedure in question is the use of emission test"averaging"to create an
"emission factor"as the basis for emissions estimation over the periods of time between actual tests. The
North Carolina Division of Air Quality(NCDAQ)has reviewed these procedures and has determined that
they are not appropriate for emissions estimation at Fayetteville Works facility for the reasons outlined
below. The NCDAQ is,therefore, requiring The Chemours Company(Chemours)to change the
emissions estimation technique and requiring Chemours to recalculate and resubmit its emission estimates
for the period beginning in January 2020 through March 2021 pursuant to permit requirements.
BACKGROUND
The NCDAQ required Chemours to conduct performance testing beginning in 2018 for the purpose of
quantifying emissions of certain per- and polyfluoroalkyl substances(PFAS)from process operations at
the Fayetteville Works facility. The initial focus of the testing was emissions of Hexafluoropropylene
Oxide Dimer Acid(I1FP0 dimer acid, C3 IWPO dieter acid(DA), or GenX, CAS No. 13252-13-6). This
required modification of exiting testing methods to capture and quantify GenX emissions from various
process operations. The testing methodology was later expanded to quantify other PFAS from process
operations at the Fayetteville Works facility.
Ultimately,the performance test data was used, in part, in the Consent Order that was finalized in the
spring of 2019 to establish emissions reductions and target dates. In addition,the Consent Order
requirements for air emissions control were incorporated into Chemours' Title V permit. Per their Title V
permit, Chemours is required to provide routine reports to NC DAQ on emissions estimates based upon
the performance test results.
North Carolina Department of Environmental Quality I Division of Air Quality
217 West Jones Street 11641 Mail Service Center I Raleigh,North Carolina 27699-1641
a,aMo; =ew,; 919.707.8400

Ms. Dawn Hughes
June 29, 2021
Page 2
As we discussed during our meeting of June 24, 2021,the use of averaging emission test results can
provide mathematically similar values for past emissions estimates when there is little variation in the
test-to-test values and could provide some insight into future projected emissions. However,as was
demonstrated by a recent performance test in March 2021 on the VEN carbon bed,this approach is flawed
when there is significant variation between test results. This approach is also not consistent with DAQ's
usual approach of estimating past air emissions from test-to-test. After reviewing all test data., Chemours
agrees that the emission averaging approach is not appropriate an procedure for emissions estimation
purposes and has agreed to change to the test-to-test approach.
NCDAQ is requiring this change be made retroactive to January 2020 for the emissions estimates
provided to DAQ for calendar year 2020, and subsequent rolling 12-month total emissions estimates
beginning in 2021,consistent with permit recordkeeping and reporting requirements_ As of June 30 `,
emission estimates through the second quarter of 2021 can also be completed and submitted to NCDAQ
for review. Although NCDAQ recognizes that the second quarter 2021 report is not officially clue
until July 30,2021,we are requesting that Chemours recalculates its emissions as expeditiously as
possible and submit the updated 2020 and 2021 (to date)emissions summary to the NCDAQ by
July 15,2021. If all monthly data from June production and operations cannot be gathered and included
in the calculations by July 16, 2 02 1,please submit data through May 2021 by this date and supplement
your submittal with the June 2021 data by July 30,2021.
We thank you for your prompt attention to this hatter. Due to COVID-19 protocols, delivery through the
US Mail Service may be delayed- Therefore,we are providing electronic copies of this letter to you. If
there are any questions,please feel free to contact me at gale- .Saundersral.ncdenr.goy or at(919)707-8413.
Sincerely,
Gary L. Saunders, Supervisor
Stationary Source Compliance Branch
Division of Air Quality,NC DEQ
cc. Christel Compton, Chemours(e-copy)
Christie Richardson,ERM(e-copy)
Mike Abraczinskas, Director,RCO (e-copy)
Michael Pjetraj,Deputy Director,RCO(e-copy)
Heather Carter, Regional Supervisor,FRO (e-copy)
Greg Reeves,FRO (e-copy)
Brent Hall, SSCB,RCO(e-copy)
Heather Sands,Permits Branch,RCO (c-copy)
IBEAM Documents (Facility ID No. 0900009)
North Carolina Department of Environmental Quality I Division of Air Quality
217 West Jones Street 1 1641 Mail Service Center I Raleigh,North Carolina 27699-1641
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Dsr.roarBtipxe1 919.707.8400