AQ_F_0900009_20200310_ST_RvwMemo (14)

Division of Air Quality
March 10, 2020
MEMORANDUM
To: Heather Carter, Fayetteville Regional Supervisor
From: Gary L. Saunders, Stationary Source Compliance Branch
Subject: The Chemours Company—Fayetteville Works
Fayetteville, Bladen County, North Carolina
Facility ID. No.0900009, Permit No.0373ST47
Performance Testing for HFPO Dimer Acid Conducted on August 23, 2018—
at Vinyl Ethers South (VES) and August 21-22, 2018 at Vinyl Ethers North (VEN) Carbon
Bed by Weston Solutions, Inc.
Tracking No. 2018-357ST
Summary of HFPO Dimer Acid Test Program
Sources Tested
During August 2018,emissions testing was conducted on two process area stacks. One series of test
runs were conducted on August 23, 2018 at the Vinyl Ethers Scrubber Stack located at the Vinyl Ethers
South (VES) process area.The VES Stack is a common stack through which emissions from VIES Scrubber
are combined with fugitive emissions collected from the enclosed areas of VES(sometimes referred to
as "room air"). Gases from various reaction vessels and unit operations in the VES process area are
vented through the caustic scrubber which reduces emissions of GenX(HFPO Dimer Acid) and its
precursors (HFPO Dinner Acid Fluoride).Although the VES can produce perfluoropropyi vinyl ether
(PPVE),the VES area will be used to produce perfluoromethyl vinyl ether(PMVE) and perfluoroethyl
vinyl ether(PEVE)for the remainder of calendar year 2018. During the testing, the HFPQ process was
operating and the VES process was producing PMVE and PEVE.The HFPO monomer escaping from the
process is not expected to be captured by the existing scrubber.
The other process area tested (August 21-22, 2018)was the carbon bed located at the Vinyl Ethers
North (VEN) process area.The carbon bed controls fugitive emissions collected from the enclosed areas
of VEN (sometimes referred to as"room air"). Gases from the outlet of the carbon bed are vented to the
Division Stack from the VEN process area. Gases from various reaction vessels and unit operations in
the hexafluoropropylene oxide (HFPO) and VEN processes are vented through the WGS,a caustic
scrubber which reduces emissions of GenX(HFPO Dimer Acid) and its precursors(HFPO Dimer Acid
Fluoride).The HFPO monomer escaping from the process is not expected to be captured by the existing
scrubber. These gases were not sampled during this test.

Sampling Method
Testing was conducted using a modified EPA Method 0010 found in the SW-846 compendium of Test
Methods for Evaluating Solid Waste:Physical/Chemical Methods. This sampling train is a variation of the
EPA Reference Method 5 found in 40 CFR 60,Appendix A. The Method 0010 train extracts a sample
isokinetically from the gas stream, passes the sample through a temperature-controlled filter,through a
temperature-controlled condenser and into a series of XAD-2 resin "traps" and impingers to capture and
collect the materials that passed through the filter. The test method is designed to capture certain
particulate and condensable materials for later recovery and analysis.
After sample recovery,the samples were sent to Chemours' contractor,Test America's laboratory in
Denver, Colorado. GenX was extracted from the resin traps. The DAQ required split samples after
extraction to be submitted for independent analysis. This summary of results only addresses the results
provided by Test America for Chemours. Laboratory analysis and quantification was performed using a
liquid chromatography column and a dual mass spectrometer(LC/MS/MS).
Test Results
The reported HFPO test results reflect corrected emission rates accounting for dilution and spike
recovery values.
Vinyl Ethers South Test Results
HFPO emissions testing of the VES scrubber was conducted on August 23, 2018 while producing PMVE
and PEVE. Two runs were conducted during the test. Each sampling run was 90 minutes in length. The
emission rate is the combination of the process gases through the scrubber and the room air emissions
because of the current stack configuration. The per run emission rate and average is displayed in the
table below.
Table 1. Summary of Stack Test Results for VES on August 23, 2018
HFPO Dimer Acid Emission Rate
Test Method Run Number
Ib/hr g/sec
1 2.62E-02 3.30E-03
Modified Method 0010 2 2.04E-02 2.57E-03
Average 2.33E-02 2.94E-03
Vinyl Ethers North Area Test Results
Inlet and outlet emissions from the VEN carbon bed adsorber were measured on August 21 and 22,2018
to determine the removal efficiency of HFPO Dimer Acid from the process fugitive emissions designated
as "room air." The carbon bed is currently used only for the control of room air. Each test run was 90
minutes in length_ The process was operating normally and was producing PPVE.

Table 2. Summary of Stack Test Results for VEN Carbon Bed on August 21-22,2018
HFPO Dimer Acid Emission Rate
RunTest Method Number Inlet Outlet % Removal
(lb/hr) (lb/hr) Efficiency
1 4.18E-02 8.53E-04 98.0
Modified Method 2 5.17E-02 9.06E-04 98.2
0010 4.00E-02
3 7.94E-04 98.0
Average 4.45E-02 8.51E-04 98.1
Summary and Conclusions
NC DAQ staff members were on site during each day that source testing occurred. DAQ staff observed
the source test teams,the sample recovery and the process operations. Based upon the onsite
observation of the testing and review of the test report, NC DAQ concludes that the testing was
conducted in accordance to the modified testing protocol submitted by Chemours and that the
analytical results appear representative of the stack conditions and process operations during the
testing.
Cc: Central Files—Bladen County
IBEAM Documents-0900009