2021.03.30_CCO.p2.1.B_ThermalOxidizerDETestReport

THERMAL OXIDIZER PERFORMANCE TEST REPORT
CHEMOURS COMPANY FAYETTEVILLE WORKS

PREPARED FOR:

THE CHEMOURS COMPANY
FAYETTEVILLE WORKS PLANT
22828 NC HWY 87 WEST
FAYETTEVILLE, NC 28306

MARCH 2021, REVISION 0
FOCUS PROJECT NO. P-001446

PREPARED BY:

FOCUS ENVIRONMENTAL INC.
4700 PAPERMILL DRIVE
KNOXVILLE, TENNESSEE 37909
[phone]
http://www.focusenv.com

The Chemours Company
Fayetteville Facility
Thermal Oxidizer Test Report
Revision: 0, March 2021

Chemours TO DE Test Report 30-Mar-21 i Focus Project No. P-001446
Tables of Contents
1.0 EXECUTIVE SUMMARY .................................................................................................................... 1
2.0 INTRODUCTION ................................................................................................................................ 2
2.1 FACILITY BACKGROUND INFORMATION .............................................................................. 2
2.2 BRIEF ENGINEERING DESCRIPTION .................................................................................... 2
2.3 THERMAL OXIDIZER TEST PROTOCOL DEVELOPMENT ................................................... 2
2.3.1 Test Plan Target Compounds ...................................................................................... 3
2.3.2 Sampling and Analytical Design Basis ......................................................................... 3
2.3.3 Developed Sampling Methods ..................................................................................... 4
2.3.3.1 Modified Method 18 Sampling ...................................................................... 4
2.3.3.2 Modified Method 0010 Sampling .................................................................. 5
2.3.4 Sampling Locations and Methods ................................................................................ 5
2.3.4.1 Waste Gas Feed Line Sampling ................................................................... 6
2.3.4.2 Stack Gas Modified Method 18 Sampling .................................................... 6
2.3.4.3 Stack Gas Modified Method 0010 Sampling ................................................ 7
2.3.5 Sample Analyses .......................................................................................................... 7
2.3.5.1 Waste Gas Line Analyses ............................................................................. 7
2.3.5.2 Stack Gas Method 18 Analyses .................................................................... 7
2.3.5.3 Stack Gas Method 0010 Analyses ................................................................ 8
2.3.6 PFAS Feed and Stack Emission Rates ........................................................................ 9
2.3.7 Other Sampling and Analysis ....................................................................................... 9
3.0 TEST PROGRAM SUMMARY ......................................................................................................... 16
3.1 PERFORMANCE OBJECTIVE ................................................................................................ 16
3.2 TEST IMPLEMENTATION SUMMARY ................................................................................... 16
3.3 TEST OPERATING OBJECTIVES .......................................................................................... 16
3.4 DEVIATIONS FROM THE TEST PLAN .................................................................................. 16
4.0 TEST RESULTS ............................................................................................................................... 21
4.1 TEST DATA REDUCTION BASIS ........................................................................................... 21
4.2 WASTE GAS CHARACTERIZATION AND TARGET PFAS COMPOUND
FEED RATES .......................................................................................................................... 21
4.3 TARGET PFAS COMPOUND STACK EMISSION RATES .................................................... 24
4.3.1 Modified Method 0010 Measured Emissions ............................................................. 24
4.3.2 Modified Method 18 Measured Emissions ................................................................. 25
4.4 TOTAL PFAS DESTRUCTION EFFICIENCY ......................................................................... 27
5.0 QUALITY CONTROL ........................................................................................................................ 35
5.1 WASTE GAS SAMPLING ........................................................................................................ 35
5.1.1 Monomer Waste Gas Sampling ................................................................................. 35
The Chemours Company
Fayetteville Facility
Thermal Oxidizer Test Report
Revision: 0, March 2021

Chemours TO DE Test Report 30-Mar-21 ii Focus Project No. P-001446
5.1.2 Polymer Waste Gas Sampling ................................................................................... 36
5.2 WASTE GAS ANALYSES ....................................................................................................... 36
5.2.1 Monomer Waste Gas Analyses .................................................................................. 36
5.2.2 Polymer Waste Gas Analyses .................................................................................... 36
5.3 STACK GAS SAMPLING ........................................................................................................ 37
5.3.1 Stack Gas Modified Method 18 Results ..................................................................... 37
5.3.2 Stack Gas Modified Method 0010 Results ................................................................. 38
5.3.3 Positive HFPO-DA Results ......................................................................................... 39
5.4 PROCESS WATER ANALYSES ............................................................................................. 39
5.5 OVERALL DATA QUALITY ASSESSMENT ........................................................................... 40
6.0 CONCLUSION .................................................................................................................................. 56

The Chemours Company
Fayetteville Facility
Thermal Oxidizer Test Report
Revision: 0, March 2021

Chemours TO DE Test Report 30-Mar-21 iii Focus Project No. P-001446
List of Tables
Table 1-1. Thermal Oxidizer Total PFAS Destruction Efficiency ................................................................. 1
Table 2-1. Properties and Structures of Target Destruction Efficiency PFAS Compounds ....................... 10
Table 2-2. Analysis and Reporting Convention for Test Samples ............................................................. 11
Table 3-1. Thermal Oxidizer Performance Test Sampling and Analysis ................................................... 17
Table 3-2. Thermal Oxidizer Performance Test Sampling Dates and Times ............................................ 20
Table 3-3. Thermal Oxidizer Destruction Efficiency Test Operating Data ................................................. 20
Table 4-1. Thermal Oxidizer Monomer Tank Feed (Line #1) Summary Analyses .................................... 28
Table 4-2. Thermal Oxidizer Polymer Tank Feed (Line #2) Summary Analyses ...................................... 29
Table 4-3. Thermal Oxidizer Monomer Tank (Line #1) Sampling Results and Feed Rates ...................... 30
Table 4-4. Thermal Oxidizer Polymer Tank (Line # 2) Sampling Results and Feed Rates ....................... 31
Table 4-5. Thermal Oxidizer Modified Method 0010 Emissions Results ................................................... 32
Table 4-6. Thermal Oxidizer Stack Modified Method 18 Sample Analyses ............................................... 33
Table 4-7. Thermal Oxidizer Modified Method 18 Stack Emissions Results ............................................. 34
Table 4-8. Thermal Oxidizer Total PFAS Destruction Efficiency ............................................................... 34
Table 5-1. Monomer Waste Gas Method 8260B Analysis Surrogate Recoveries ..................................... 41
Table 5-2. Monomer Waste Gas Method 8321A Analysis Surrogate Recoveries ..................................... 42
Table 5-3. Polymer Waste Gas Method 8260B Analysis Surrogate Recoveries ....................................... 43
Table 5-4. Polymer Waste Gas Method 8321A Analysis Surrogate Recoveries ....................................... 44
Table 5-5. Stack Gas Modified Method 18 Analysis Surrogate Recoveries ............................................... 45
Table 5-6. Stack Gas Modified Method 0010 Analysis Surrogate Recoveries ........................................... 46
Table 5-7. Thermal Oxidizer Modified Method 0010 Analysis Results ...................................................... 47
Table 5-8. Thermal Oxidizer Process Water Analyses .............................................................................. 48

The Chemours Company
Fayetteville Facility
Thermal Oxidizer Test Report
Revision: 0, March 2021

Chemours TO DE Test Report 30-Mar-21 iv Focus Project No. P-001446

List of Figures
Figure 2-1. Thermal Oxidizer Process Flow Schematic ............................................................................. 12
Figure 2-2. Modified Method 18 Sampling Train Schematic ...................................................................... 13
Figure 2-3. Modified Method 0010 Sampling Train Schematic .................................................................. 14
Figure 2-4. Installed Waste Gas Sampling Point Schematic ..................................................................... 15
Figure 5-1. Monomer Waste Gas (Line #1) Modified Method 18 COF2 Capture ....................................... 49
Figure 5-2. Monomer Waste Gas (Line #1) Modified Method 18 HFPO Capture ...................................... 50
Figure 5-3. Monomer Waste Gas (Line #1) Modified Method 18 HFPO-DA Capture ............................... 51
Figure 5-4. Polymer Waste Gas (Line #2) Modified Method 18 HFPO-DAF Capture ............................... 52
Figure 5-5. Polymer Waste Gas (Line #2) Modified Method 18 COF2 Capture ......................................... 53
Figure 5-6. Polymer Waste Gas (Line #2) Modified Method 18 Fluoroether E-1 Capture ........................ 54
Figure 5-7. Polymer Waste Gas (Line #2) Modified Method 18 HFPO-DA Capture ................................. 55

List of Attachments (Provided on Compact Disk)
Source Emissions Testing of a Thermal Oxidizer and Scrubber System Stack, The Chemours Company –
Fayetteville, North Carolina, Ramboll, March 2021.

Summaries of the following analyses performed by Eurofins TestAmerica are presented as Appendix D of
the Ramboll report noted above. The complete analytical data packages are provided with this report on
compact disk.

Eurofins TestAmerica Analytical Data Packages
Data Pkg. No. Description
140-21803-1 Final Report-Monomer Line #1 Method 18
140-21804-1 Final Report-Polymer Line #2 Method 18
140-21805-1 Final Report-Waste Gas Line Method 18 QC
140-21799-1 Final Report-Stack Gas Method 18
140-21800-1 Final Report-Stack Gas Method 18 QC
140-21801-1 Final Report-Stack Gas Method 0010
140-21802-1 Final Report-Stack Gas Method 0010 QC
140-21806-1 Final Report-Process Water Samples
The Chemours Company
Fayetteville Facility
Thermal Oxidizer Test Report
Revision: 0, March 2021

Chemours TO DE Test Report 30-Mar-21 v Focus Project No. P-001446
List of Acronyms

amu atomic mass units
ASTM American Society for Testing and Materials
CaF2 calcium fluoride
CF4 tetrafluoromethane
CO carbon monoxide
CO2 carbon dioxide
COC chain of custody
COF2 carbonyl difluoride
DE destruction efficiency
DQO data quality objective
DMC dimethyl carbonate
dscf dry standard cubic feet (EPA standard at 68oF, 1 atmosphere)
dscm dry standard cubic meter (EPA standard at 68oF, 1 atmosphere)
E-1 Heptafluoropropyl-1,2,2,2-tetrafluoroethyl ether (Fluoroether E-1)
EPA Environmental Protection Agency
HF hydrogen fluoride (gas) or hydrofluoric acid (aqueous)
HFPO hexafluoropropylene oxide (HFPO), a.k.a., “HFPO monomer” or simply “monomer”
HFPO-DA hexafluoropropylene dimer acid or C3-dimer, a.k.a., “HFPO dimer”, “dimer acid”, “dimer”, or
Gen X
HFPO-DAF hexafluoropropylene dimer acid fluoride, a.k.a., “HFPO dimer fluoride”, “dimer acid
fluoride”, or simply “dimer fluoride”
HFPO-DOCH3 HFPO dimer, methyl ester
HPLC/MS/MS high performance precision liquid chromatography/tandem mass spectrometry
hr hour
GC/MS gas chromatography/mass spectrometry
LCS laboratory control sample
lpm liters per minute
MDL method detection limit
min minute
MMBtu million British thermal units
2-MTP methyl-2-methoxy-tetrafluoro-propionate
NCDAQ North Carolina Department of Air Quality
N2 nitrogen
O2 oxygen
OPL operating parameter limit
OTM Other Test Method
PFAS per- or poly-fluorinate alkyl substance
PFOA perfluorooctanoic acid
PFOS perfluorooctane sulfonic acid
psia pounds per square inch absolute (psig + atmospheric pressure)
psig pounds per square inch gauge
QA quality assurance
QC quality control
RFA request for analysis
RL reporting limit
RPD relative percent difference
RSD relative standard deviation
SOP standard operating procedure
SVOC semi-volatile organic compound
TFE tetrafluoroethylene
VOC volatile organic compound

Chemours TO DE Test Report 30-Mar-21 1 Focus Project No. P-001446
1.0 EXECUTIVE SUMMARY
This report presents the results of per- and poly-fluoroalkyl substance (PFAS) destruction efficiency (DE)
performance testing conducted January 26-28, 2021 on the thermal oxidizer located at The Chemours
Company FC, LLC (Chemours) facility, Fayetteville, North Carolina. Per the consent order, “Chemours
shall demonstrate that the thermal oxidizer controls all PFAS at an efficiency of 99.99%”. Chemours also
holds a Title V permit which contains the same thermal oxidizer requirements and requires the testing
protocol “to address how the Permittee will ensure the Thermal Oxidizer and 4-Stage Scrubber System
will achieve the emission reduction [of 99.99%], including the use of a surrogate for all PFAS, such as the
hexafluoropropylene oxide (HFPO).” A test plan delineating the thermal oxidizer DE performance test
target operating conditions, and the sampling and analytical protocols, was submitted to the North
Carolina Department of Air Quality (NCDAQ) on December 9, 2019. Chemours conducted the initial
thermal oxidizer performance test on February 28-29, 2020 in substantial conformance with the approved
test plan. This report presents the PFAS DE results of the first recurring performance test.
During the test, both the monomer and polymer manufacturing operations directed PFAS-bearing waste
gases to the thermal oxidizer. The test program characterized the waste gas feed materials and
measured the emission rates of five (5) target PFAS compounds:
• HFPO (Hexafluoropropylene oxide), a.k.a., “HFPO monomer” or simply “monomer”,
• HFPO-DA (Hexafluoropropylene Dimer Acid or C3-Dimer), a.k.a., “HFPO dimer”, “dimer acid”,
“dimer” or “Gen X”,
• HFPO-DAF (Hexafluoropropylene Dimer Acid Fluoride),
• COF2 (Carbonyl Difluoride), and
• Fluoroether E-1 (Heptafluoropropyl-1,2,2,2-tetrafluoroethyl ether).

System DE performance was calculated based on the sum of the system inlet feed rates and sum of the
stack emissions rates of these five (5) compounds. “Total PFAS” is the arithmetic sum of HFPO, HFPO-
DA, HFPO-DAF, COF2, and Fluoroether E-1 under these conditions. The total PFAS DE results are
summarized in Table 1-1.
Table 1-1. Thermal Oxidizer Total PFAS Destruction Efficiency
Chemours Company FC, LLC, Fayetteville, North Carolina, January 26-28, 2021
Run 1 Run 2 Run 3 Average
99.99920% 99.99968% 99.99963% 99.99951%

The total PFAS DE performance exceeded 99.999% during all three (3) test runs. The balance of this
report presents the details of the testing performed.

Chemours TO DE Test Report 30-Mar-21 2 Focus Project No. P-001446
2.0 INTRODUCTION
2.1 FACILITY BACKGROUND INFORMATION
The Chemours Company FC, LLC (Chemours) manufactures chemicals, plastic resins, plastic sheeting,
and plastic film at the facility located at 22828 NC Highway 87 West, Fayetteville, Bladen County, North
Carolina (the facility). Under the consent order executed and filed February 25, 2019 Chemours was
required to install a thermal oxidizer for control of per- and poly-fluoroalkyl substance (PFAS) process
stream emissions from identified manufacturing operations. A test plan delineating the thermal oxidizer
destruction efficiency (DE) performance test target operating conditions, and the sampling and analytical
protocols, was and submitted to the North Carolina Department of Air Quality (NCDAQ) on December 9,
2019. NCDAQ gave approval of the test plan via letter dated January 27, 2020. The initial DE
performance test was conducted February 28-29, 2020. This test report documents the operating
conditions, and the sampling and analytical test results of the first recurrent DE performance test
conducted January 26-28, 2021 following the protocols of the same test plan previously approved by
NCDAQ.
2.2 BRIEF ENGINEERING DESCRIPTION
The thermal oxidizer and its associated 4-stage scrubber are identified in the Air Quality Permit
respectively as control devices NCD-Q1 and NCD-Q2. Please refer to Figure 2-1. The thermal oxidizer is
a 10 million BTU per hour (MMBtu), natural gas-fired device. Waste gases from the manufacturing
operations process streams are collected via header systems, compressed and delivered by pipeline to
the thermal oxidizer for destruction of the entrained PFAS compounds. Thermal oxidizer emissions are
treated in the scrubber system to control hydrogen fluoride (HF) generated by PFAS compound
combustion. The scrubber system consists of a 4-stage packed bed column with three water scrubbing
stages and one caustic scrubbing stage.
2.3 THERMAL OXIDIZER TEST PROTOCOL DEVELOPMENT
The properties of each PFAS compound are sufficiently unique such that no singular sampling and
analysis approach is appropriate for a comprehensive characterization of all PFAS compounds handled at
Chemours Fayetteville Works. The physical and chemical properties of each of the potential target PFAS
compounds must be considered when developing a sampling and analytical protocol.
The sampling and analytical protocols employed for this test program were developed by Chemours
through consultation with Eurofins TestAmerica, Inc. The technical discussion presented in the following
sections underlies the sampling and analytical technical basis used to conduct this performance test, and
the performance conclusions derived from the results presented in this test report.

Chemours TO DE Test Report 30-Mar-21 3 Focus Project No. P-001446
2.3.1 Test Plan Target Compounds
The thermal oxidizer DE performance test program was designed based on the characterizations of site-
specific target PFAS compounds. The five (5) target compounds were:
• HFPO (Hexafluoropropylene oxide), a.k.a., “HFPO monomer” or simply “monomer”,
• HFPO-DA (Hexafluoropropylene Dimer Acid or C3-Dimer), a.k.a., “HFPO dimer”, “dimer acid”,
“dimer” or “Gen X”,
• HFPO-DAF (Hexafluoropropylene Dimer Acid Fluoride),
• COF2 (Carbonyl Difluoride), and
• Fluoroether E-1 (Heptafluoropropyl-1,2,2,2-tetrafluoroethyl ether).

Table 2-1 presents a summary of the chemical composition and structural information, and key chemical
and physical property data for the five (5) PFAS compounds targeted for this test program.
The base compounds handled and used at the Fayetteville facility are HFPO and HFPO-DA. HFPO-DAF
is a synthetic precursor to HFPO-DA in the chemical process. The molecular structure of HFPO-DAF is
identical to HFPO-DA except fluorine (F) is substituted in place of the hydroxyl (-OH) group. This
difference between HFPO-DA and HFPO-DAF has substantial impact on the physical properties and
chemical reactivity of these otherwise structurally similar compounds. An additional reactant compound,
COF2, is a major constituent in the waste gas. Fluoroether E-1 is a thermal decarboxylation product of
HFPO-DA and appears as an intermittent major constituent in the waste gas. The combined feed rates
to the thermal oxidizer and the concurrently measured emission rates of HFPO, HFPO-DA, HFPO-DAF,
COF2, and Fluoroether E-1 from the thermal oxidizer were established to demonstrate PFAS DE
performance.
2.3.2 Sampling and Analytical Design Basis
HFPO, HFPO-DAF, and COF2 react with methanol (MeOH) to form ester compounds as depicted below:
• HFPO + MeOH → 2-MTP + 2HF
• HFPO-DAF + MeOH → HFPO-DOCH3 + HF
• COF2 + 2MeOH → DMC + 2HF.

The 2-MTP stands for methyl-2-methoxy-tetrafluoro-propionate. The HFPO-DOCH3 stands for HFPO
dimer, methyl ester. The DMC stands for dimethyl carbonate. All three (3) ester compounds are
analyzed via SW-846 Method 8260. The sampling and analytical strategy for HFPO, HFPO-DAF, and
COF2 is designed based on the reaction of these compounds with methanol to form derivative reaction
products, and quantifying them based on analysis of their reaction products.
The Fluoroether E-1 and HFPO-DA sampling and analytical strategy was designed based on capturing
the compounds via condensation and dissolution in the methanol impingers. Fluoroether E-1 is captured
as a volatile organic compound (VOC), and then quantified via direct analysis using SW-846 Method

Chemours TO DE Test Report 30-Mar-21 4 Focus Project No. P-001446
8260. HFPO-DA is captured as a semi-volatile organic compound (SVOC) and then quantified via direct
analysis using EPA Method 537.
2.3.3 Developed Sampling Methods
Two (2) sampling methods were developed and employed for this test program. Please refer to Figures
2-2 and 2-3. One method is based on EPA Method 18. The second is based on SW-846 Method 0010.
[Note: The modified SW-846 Method 0010 sampling methodology set forth in the approved test plan and
used during this test program is substantially equivalent to Other Test Method-45 (OTM-45) posted to
EPA’s Air Emission Measurement Center (EMC) website on January 13, 2021:
https://www.epa.gov/sites/production/files/2021-01/documents/otm_45_semivolatile_pfas_1-13-21.pdf].
The following sections describe the sampling methods, the associated specialized techniques, and their
application during this test program.
2.3.3.1 Modified Method 18 Sampling
The Modified Method 18 (MM18) sampling train consists of six (6) PFA fluoropolymer impingers and
connectors configured in series. The impingers are charged with methanol. For sampling, the impingers
are immersed in a methanol bath chilled using dry ice to maintain a temperature of -73oC (-100oF) or less.
The principle of operation is to capture the target PFAS compounds by condensation and/or chemical
reaction within the methanol media. The six (6) successive impingers are designed to provide sufficient
condensing, absorbing, and reaction capacity to capture the target PFAS analytes. The sampling train is
connected to a dry gas meter sampling system to measure the volume of dry gas sampled. At the
conclusion of a test run, the six (6) sampling train impingers are recovered as discrete (individual)
samples and analyzed separately.
The Modified Method 18 sampling method captures the target PFAS compound vapors via condensing
and/or reaction with methanol as the sampled gas is sparged through the successive chilled methanol
matrix. Two (2) of the five (5) target compounds, Fluoroether E-1 and HFPO-DA, are captured by simply
condensing them from the gas stream and dissolving them in methanol. Three (3) of the five (5)
compounds, HFPO, HFPO-DAF, and COF2, react with the methanol to form ester compounds as
previously described. The HFPO and COF2 have respective boiling points of -28oC and -85oC, but their
reaction with methanol to form the higher boiler point derivative ester compounds is key to facilitating the
measurement of these compounds. The boiling points of the ester compounds formed from HFPO and
COF2 are higher and therefore easier to recover and retain similar to standard EPA volatile organic
compound (VOC) analytes. Post-sampling preservation of these samples is by refrigeration using wet ice
to 4oC.

Chemours TO DE Test Report 30-Mar-21 5 Focus Project No. P-001446
2.3.3.2 Modified Method 0010 Sampling
Based on its boiling point of 151oC, HFPO-DA is classified by EPA as a semi-volatile organic compound
(SVOC) that can potentially condense and possibly attach to particulate matter. Therefore, to accurately
measure the stack emissions of HFPO-DA, the sampling is conducted using an iso-kinetic sampling
method.
The sampling train is generally configured like a standard Method 0010 sampling train with a heated
probe and filter, condenser coil, XAD-2 resin cartridge, deionized water impingers, and a silica gel
impinger. An added feature is a second XAD-2 resin cartridge located between the last deionized water
impinger and the silica gel impinger. The purpose of the second XAD-2 resin cartridge is to act as a
quality indicator to assess possible target analyte breakthrough. Other specialized aspects of the
Modified Method 0010 sampling are:
• During sampling collection, the sampling probe temperature is maintained a few degrees
above the dew point of the moisture in the gas stream, well below the normal Method 5
operating temperature range of 248oF (120oC) (to preclude thermal decarboxylation of HFPO-
DA to form Fluoroether E-1)
• Maintaining the coil condenser and XAD-2 resin jacket as cold as reasonably possible below
the normal Method 0010 prescribed maximum of 68oF (20oC) temperature for best possible
conditions for HFPO-DA retention on the resin, and
• Use of 95% methanol / 5% NH4OH solution as the recovery solvent for the rinsing of
sampling train components to recover HFPO-DA from glassware surfaces.

A total of seven (7) sample fractions are generated during the Modified Method 0010 sampling train
recovery:
• Particulate filter
• Solvent (95% methanol / 5% NH4OH) rinses of the probe, nozzle, and the front-half of the
filter holder
• Primary XAD-2 resin tube
• Back-half of the filter holder, coil condenser, and connecting glassware 95% methanol / 5%
NH4OH solvent glassware rinses
• Condensate and impinger contents of Impingers #1, #2 and #3 charged with deionized (DI)
water and includes DI water rinses of the glassware
• Impingers #1, #2 and #3 solvent (95% methanol / 5% NH4OH) glassware rinses as a
separate sample (NOT combined with the impinger water and DI water rinses), and
• Breakthrough XAD-2 resin tube.
2.3.4 Sampling Locations and Methods
The test program sampling campaign was designed to characterize the feed materials to the thermal
oxidizer and the corresponding emissions of the target PFAS compounds. The sampling locations are:
1) the monomer waste gas feed line (Line #1),

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2) the polymer waste gas feed line (Line #2), and
3) the thermal oxidizer/scrubber stack.
The sampling techniques used at each location are discussed in the following sections. During testing, all
locations were sampled concurrently.
2.3.4.1 Waste Gas Feed Line Sampling
The two (2) waste gas feed lines to the thermal oxidizer were sampled separately at points on the 3-inch
lines from the accumulator tanks to the thermal oxidizer. The gas pressure in these lines is nominally 10-
30 psig. To perform the sampling, Chemours designed, fabricated, and installed permanent sampling
probes in these lines. Please refer to Figure 2-4. The permanently installed probes include a nozzle
centered in the line and oriented to face into the stream flow, similar to the orientation of an isokinetic
sampling probe when sampling stack gas. The installed sampling probe apparatus includes Swagelok®
connectors that allow for connection of the sampling trains to the feed lines without line breaks. Ball
valves allow for starting and stopping the flow of pressurized gas. The “bleed” connection allows for
connection to a compressed nitrogen line to purge and clear the sampling location of any buildup of liquid
or debris prior to sampling, and after sampling is completed. The previously described Modified Method
18 sampling train was used to sample the waste gas lines for the five (5) target PFAS compounds: HFPO,
HFPO-DA, HFPO-DAF, COF2, and Fluoroether E-1.
The sampling train meter box includes a needle control valve. No vacuum pump is required; the waste
gas feed line pressure provides the sampled gas motive force. The meter box needle control valve is
used to throttle and control the flow rate of the waste gas through the sampling train. The dry gas meter
is used to measure the dry gas flow rate and the total volume of dry inert gas sampled.
The two (2) waste gas feed lines were sampled concurrently using two sampling trains, one on each of
the waste gas feed lines. The target sampling rate was maintained at approximately 0.50 liters per
minute. Waste gas feed lines sampling was also performed concurrently with the stack gas emissions
sampling at the thermal oxidizer/scrubber stack. Dry gas meter flow, pressure, and temperature data
were used to determine the total mass of dry gas sampled. Nitrogen is used in the system as the inert
sweep gas for the waste gases in the vent header systems. Therefore, the waste gas dry gas
composition was assumed to be 100% nitrogen and assigned a molecular weight of 28 amu. Pre- and
post- sampling impinger differential weights were used to determine the mass of organic constituent
vapors condensed in the sampling train from the sampled waste gases.
2.3.4.2 Stack Gas Modified Method 18 Sampling
A Modified Method 18 sampling train was used to sample the stack gas for four (4) of the five (5) target
PFAS compounds: HFPO, HFPO-DAF, COF2, and Fluoroether E-1. The Modified Method 18 sampling
protocol is similar as described for the waste gas feed lines except use of a vacuum pump equipped

Chemours TO DE Test Report 30-Mar-21 7 Focus Project No. P-001446
metering system was required to draw the sampled stack gas through the sampling train. The target
sampling rate was 1.5-2.0 liters per minute. Dry gas meter flow, pressure, and temperature data were
used to determine the total volume of dry gas sampled. Dry gas molecular weight was determined via
Method 3A analysis of the dry gas meter exhaust.
2.3.4.3 Stack Gas Modified Method 0010 Sampling
As previously noted, HFPO-DA is classified as a SVOC by EPA that can potentially condense and/or
attach to particulate matter. The HFPO-DA stack emissions are sampled iso-kinetically using a modified
SW-846 Method 0010 sampling train as previously described.
The Modified Method 0010 sampling train was operated for 180 minutes during each sampling run to
sample a minimum volume of three (3) dry standard cubic meters (dscm). The stack sampling location
traverse points were determined and performed in accordance with EPA Method 1. Stack velocity and
flow rate were determined based on EPA Method 2 (pitot tube) measurements. Dry gas meter flow,
pressure, and temperature data were used to determine the total volume of dry gas sampled. Dry gas
molecular weight was determined via Method 3A analysis of the dry gas meter exhaust. Impinger
moisture gain was used to determine stack gas moisture content per EPA Method 4.
2.3.5 Sample Analyses
Waste line and stack gas samples are analyzed as described in the following sections.
2.3.5.1 Waste Gas Line Analyses
The characterization of the five (5) target PFAS compounds in the waste gas feed lines was determined
via analysis of the Modified Method 18 impinger contents. Please refer to Table 2-2. HFPO, HFPO-DAF,
COF2, and Fluoroether E-1 were determined using Method 8260B analysis. HFPO, HFPO-DAF, and
COF2 were quantified via analysis for their respective derivative ester compounds and reported
respectively as HFPO, HFPO-DA, and COF2 equivalents. Fluoroether E-1 was quantified via direct
analysis using Method 8260B. HFPO-DA was quantified via direct analysis using EPA Method 537.
Each of the Modified Method 18 impinger samples was recovered and analyzed separately. Analysis
results were then used to calculate target analyte feed rates. The sum of the positive analysis results for
each target compound was used to determine the waste gas feed line concentration with zero being used
for non-detect values.
2.3.5.2 Stack Gas Method 18 Analyses
The emissions of the HFPO, HFPO-DAF, COF2, and Fluoroether E-1 were determined via analysis of the
Modified Method 18 impinger contents. Please refer to Table 2-2. Like the waste gas feed lines, HFPO,
HFPO-DAF, COF2, and Fluoroether E-1 are determined using Method 8260B analysis. HFPO, HFPO-
DAF, and COF2 were quantified via analysis for their respective derivative ester compounds and reported

Chemours TO DE Test Report 30-Mar-21 8 Focus Project No. P-001446
respectively as HFPO, HFPO-DA, and COF2 equivalents. Fluoroether E-1 was quantified via direct
analysis using Method 8260B.
Each of the Modified Method 18 impinger samples was recovered and analyzed separately. In
calculating target analyte emission rates, the following approach is used:
• For cases where all of the impinger analysis results are non-detect (ND) for a target analyte,
the earliest (first) impinger reporting limit (RL) is used as the Modified Method 18 train total
catch for that analyte.
• For cases where some, but not all of the impinger analysis results are non-detect (ND) for a
target analyte, the sum of the positive analysis results and the RL of earliest or last non-
detect impinger is used as the Modified Method 18 train total catch for that analyte.
• For cases where all of the impinger analysis results are positive for a target analyte, the sum
of the positive analysis results is used as the Modified Method 18 train total catch for that
analyte.

All stack gas Modified Method 18 analytical results for HFPO-DAF, COF2, and Fluoroether E-1 were non-
detect values. Therefore, the HFPO-DAF, COF2, and Fluoroether E-1 emission rates were based on the
methodology noted in the first bullet, above.
HFPO was detected at slightly above the RL in Impingers 1, 3, 4, and 6 of the Run 1 Modified Method 18.
Therefore, the Run 1 HFPO emission rates were based on the methodology noted in the second bullet
above which ends up including all seven impingers.
HFPO was not detected the Run 2 and Run 3 Modified Method 18 samples. Therefore, the Run 2 and
Run 3 HFPO emission rates were based on the methodology noted in the first bullet, above.
2.3.5.3 Stack Gas Method 0010 Analyses
The seven (7) fractions from the Modified Method 0010 sampling train components were prepared using
SW-846 Method 3542 and analyzed for HFPO-DA via EPA Method 537. Sampling train fractions were
combined as noted below and a total of four (4) separate analyses were performed per sampling train:
• Front-half composite (probe, nozzle, and filter holder front half solvent rinses, and particulate
filter)
• Back-half composite (XAD-2 resin, coil condenser and filter holder back half solvent rinses,
and impinger solvent rinses)
• Condensate and impinger contents, and
• Breakthrough XAD-2 resin tube.

The sum of the first three (3) sampling train fraction analyses noted above is used for the sampling train
total catch. The fourth fraction, the breakthrough XAD-2 resin tube, was analyzed to assess
breakthrough and is excluded from the emissions determination calculations.

Chemours TO DE Test Report 30-Mar-21 9 Focus Project No. P-001446
2.3.6 PFAS Feed and Stack Emission Rates
Waste gas feed line sampling and analysis data were reduced and reported as mass of HFPO, HFPO-
DA, HFPO-DAF, COF2, and Fluoroether E-1 per total mass of waste gas feed. These data and thermal
oxidizer waste gas line mass flow meter data were used to determine the HFPO, HFPO-DA, HFPO-DAF,
COF2, and Fluoroether E-1 mass feed rates to the thermal oxidizer.
The Modified Method 18 sampled volume data and analysis results were used to determine the HFPO,
HFPO-DAF, COF2, and Fluoroether E-1 stack emission concentrations. The Modified Method 0010
sampled volume data and analysis results were used to determine the HFPO-DA stack emission
concentration. The Modified Method 0010 stack flow data were used to determine the HFPO, HFPO-DA,
HFPO-DAF, COF2, and Fluoroether E-1 stack emission rates.
Example equations are presented in Section 4.0 of this test report.
2.3.7 Other Sampling and Analysis
In addition to the waste gas feed lines and thermal oxidizer stack emissions, the demineralized water
make-up used in the scrubber system, and the HF acid and Stage 4 purge streams from the scrubber
system were sampled and analyzed for the same five (5) target PFAS compounds. The purpose of the
analysis of the demineralized water make-up samples was to evaluate possible target analyte
contamination introduced to the stack gas scrubbing system that could impact the stack gas emissions
sampling results. The purpose for the analysis of the acid and purge samples was to evaluate the
possible fate of the target analytes.
Chemours TO DE Test Report 30-Mar-21 10 Focus Project No. P-001446 Table 2-1. Properties and Structures of Target Destruction Efficiency PFAS Compounds Compound Hexafluoropropylene oxide Hexafluoropropylene Dimer Acid or C3-Dimer Hexafluoropropylene Dimer Acid Fluoride Carbonyl Difluoride Heptafluoropropyl-1,2,2,2-tetrafluoroethyl ether Acronym HFPO HFPO-DA HFPO-DAF COF2 Fluoroether E-1 CAS No. 428-59-1 13252-13-6 2062-98-8 353-50-4 3330-15-2 Molecular Formula C3F6O C6HF11O3 C6F12O2 COF2 C5HF11O Mole Weight 166.02 330.05 332.04 66.01 286.04 Molecular Structure O||CF3 -CF2 -CF2 -O -CF -C -OH| CF3 O||CF3 -CF2 -CF2 - O - CF - C - F| CF3 CF3-CF2-CF2-O-CF–F3 Normal B.P., oC @ 760 mmHg -28 151 56 -85 40 V.P. @ 25oC, psia 98.7 (Gas) 0.0224 0.551 Gas 8.1 V.P. @ 25oC, mmHg abs 5,103 (Gas) 1.16 28.5 Gas 419 Note Reacts with methanol to form methyl-2-methoxy-tetrafluoro-propionate (2-MTP), B.P. 41oC. None Reacts with methanol to form HFPO dimer, methyl ester (HFPO-DOCH3), B.P. 116oC.Reacts with methanol to form dimethyl carbonate (DMC), B.P. 90oC. Thermal decarboxylation product of HFPO-DA OCF3 - CF- CF 2
Chemours TO DE Test Report 30-Mar-21 11 Focus Project No. P-001446 Table 2-2. Analysis and Reporting Convention for Test Samples Target Analyte Derivative Compound or Target Analyte Actually Measured in the Laboratory Analytical Method Reported Equivalent Compound HFPO Monomer CAS #428-59-1 Methyl 2-methoxytetrafluoropropionate (2-MTP) CAS #10186-63-7 SW-846 Method 8260 HFPO Monomer CAS #428-59-1 HFPO-DAF CAS #2062-98-8 HFPO, Dimer Methyl Ester CAS #13140-34-6 SW-846 Method 8260 HFPO-DAF CAS #2062-98-8 Carbonyl Difluoride CAS #353-50-4 Dimethyl Carbonate CAS #616-38-6 SW-846 Method 8260 Carbonyl Difluoride CAS #353-50-4 Fluoroether E-1 CAS #3330-15-2 Fluoroether E-1 CAS #3330-15-2 SW-846 Method 8260 Fluoroether E-1 CAS #3330-15-2 HFPO-DA (C3-Dimer) CAS #13252-13-6 HFPO-DA (C3-Dimer) CAS #13252-13-6 EPA Method 537 HFPO-DA (C3-Dimer) CAS #13252-13-6

Chemours TO DE Test Report 30-Mar-21 12 Focus Project No. P-001446
Natrual Gas
Air
Stack
Thermal
Oxidizer
Catch
Tank
Monomer
Manufacturing
Vents
1st
Stage
Recycle
Polymer
Manufacturing
Vents
2nd
Stage
3rd
Stage
4th
Stage
Recycle
Recycle
Recycle
Demineralized
WaterMakup
Demineralized
WaterMakup
Caustic
Purge to
Offsite
Disposal
CaF2 Unit
Purge to
Offsite
Disposal
To Atmosphere
CaF2 to
Offsite
Disposal
Scrubber
Gas Stream
Water Stream

Figure 2-1. Thermal Oxidizer Process Flow Schematic

Chemours TO DE Test Report 30-Mar-21 13 Focus Project No. P-001446 Figure 2-2. Modified Method 18 Sampling Train Schematic P:\1_PBB Project Files\Chemours_102017\Handout for Raleigh NC Meeting on December 6 2019\Modified Method 18 Train Schematic for Chemours_3 Compounds_FINAL_112719.vsdCreated by Patti Bales_Last Edited on 3/17/2020 12:40 PM CENTROID OF STACK OR DUCT TO BE SAMPLEDSTACK GAS FLOWMoisture & Condensables Knockout MidgetImpinger #1DRY ICE/ MeOH BATHImpinger #2Impinger #4Schematic of Modified Method 18 Sampling Train for Sampling Waste Gas forHexafluoro Propylene Oxide (HFPO), HFPO-DA and HFPO-DAF and Analytical Assessment by SW-846 Method 8260BImpinger #3UMBILICAL CORDTHERMOCOUPLE OR TEMPERATURE READOUTImpinger #6Impinger #5METER BOX CONTAININGROTAMETER, DRY GAS METER, PUMP, FLOW CONTROLS, AND TEMPERATURE READOUT, AND PROBE HEAT CONTROLSISOLATION VALVESAMPLING MODEVACUUM RELEASE MODELEAK CHECK (VACUUM) MODECHARCOAL TRAPIMPINGERS CHARGED WITH METHANOL (100 mL EACH)TWO-WAY PTFE ISOLATION VALVESTHREE-WAY PTFE ISOLATION VALVE
Chemours TO DE Test Report 30-Mar-21 14 Focus Project No. P-001446 Figure 2-3. Modified Method 0010 Sampling Train Schematic

Chemours TO DE Test Report 30-Mar-21 15 Focus Project No. P-001446

Figure 2-4. Installed Waste Gas Sampling Point Schematic
<------ BALL VALVE
<------ BALL VALVE<------ BALL VALVESwagelok®
Connection for
Sampling Train
Connection
for
Compressed
Nitrogen
Purge
------------------>GAS FLOW

Chemours TO DE Test Report 30-Mar-21 16 Focus Project No. P-001446
3.0 TEST PROGRAM SUMMARY
3.1 PERFORMANCE OBJECTIVE
The thermal oxidizer test performance objective was to demonstrate 99.99% DE of PFAS compounds.
The test program was designed to characterize and determine the inlet feed rates, and the stack
emissions rates of five (5) site-specific target compounds: HFPO, HFPO-DA, HFPO-DAF, COF2, and
Fluoroether E-1. The development details of the sampling and analysis methodologies used are
presented in the preceding Section 2.0. System DE performance was calculated based on the sum of the
system inlet feed rates, and sum of the stack emissions rates of these five (5) compounds.
3.2 TEST IMPLEMENTATION SUMMARY
Table 3-1 summarizes the test program sampling and analysis. The thermal oxidizer test program was
conducted January 26-28, 2021. Three (3) runs of waste gas feed line sampling and thermal oxidizer
emissions sampling were performed. Table 3-2 summarizes the sampling dates and times. The
performance test was conducted in substantial conformance with the approved test plan.
3.3 TEST OPERATING OBJECTIVES
The thermal oxidizer operating conditions are summarized in Table 3-3. The one-minute operating data
are included as Appendix A of the Ramboll report.
3.4 DEVIATIONS FROM THE TEST PLAN
Three deviations from the approved test plan are noted:
• Sampling and analysis for a fifth compound, Fluoroether E-1, was added to the
sampling and analysis scope. This addition to the test program expanded the
amount of target PFAS compounds potentially characterized in the waste gas feed
and emissions for DE performance determination.
• Sampling of the Stage 1 scrubber purge stream was deleted from the test program.
Sampling of this stream was primarily included in the test plan as an option to
sampling of the HF acid stream. Sampling of either stream provides similar process
information. Deletion of the Stage 1 scrubber purge stream sampling had no impact
on test results or determinations.
• An additional (7th) impinger was added to the stack gas Modified Method 18 sampling
train serving primarily as a moisture knockout trap. This impinger was charged with
methanol, and placed in-series as the 1st impinger, preceding the other six (6)
impingers described in Section 2.3.3.1. This added 7th impinger was not chilled with
dry ice as the other six (6) were, but was maintained in a separate regular ice water
bath at approximately 2˚C to knock out moisture vapor while avoiding the freezing of
condensed water from the stack gas. Condensed moisture from the stack gas would
potentially freeze in the 1st methanol/dry ice bath impinger or connecting tubing
possibly plugging up the sampling train. This additional impinger was recovered,
analyzed and reported as a separate sample.
Chemours TO DE Test Report 30-Mar-21 17 Focus Project No. P-001446 Table 3-1. Thermal Oxidizer Performance Test Sampling and Analysis Sample Name Sampling Location/ Access Sampling EquipmentSampling Reference Method 1 Sample Size/Frequency- Target Analyte(s) Analytical Reference Method 2 Monomer Waste Gas Feed Line #1 Specially fabricated sampling port Modified Method 18 Sampling Train EPA Method 18 0.5-1.0 liters per minute concurrent with Method 0010 stack gas sampling HFPO-DAF, HFPO, COF2, & Fluoroether E-1 HFPO-DASW8-46 Method 8260B (Reaction Products) EPA Method 537 2Polymer Waste Gas Feed Line #2 Specially fabricated sampling port Modified Method 18 Sampling Train EPA Method 18 0.5-1.0 liters per minute concurrent with Method 0010 stack gas sampling HFPO-DAF, HFPO, COF2, & Fluoroether E-1 HFPO-DASW-846 Method 8260B (Reaction Products) EPA Method 537 2Stack Gas Stack Port Modified Method 18 Sampling Train EPA Method 18 ~2.0 liters per minute concurrent with Method 0010 stack gas sampling HFPO, HFPO-DAF, COF2, & Fluoroether E-1 SW-846 Method 8260B (Reaction Products) Stack Gas Isokinetic Port Modified Method 0010 Sampling Train SW-846 Method 0010 Minimum sampled volume of 3.0 dry standard cubic meters 3,4 HFPO-DA EPA Method 537 2 Demineralized Makeup Water Tap on line 50-100 mL Plastic Graduated Cylinder; 60 and 1000 mL HDPE Sample Bottles ASTM E-300-86 Sampling Frequency: At the start of the test run and at 60-minute intervals during each test run. Sample Size: Note 5 HFPO, HFPO-DAF, COF2, & Fluoroether E-1 HFPO-DA SW-846 Method 8260B (Reaction Products) EPA Method 537 HF Acid Stream Tap on line 50-100 mL Plastic Graduated Cylinder; 60 and 1000 mL HDPE Sample Bottles ASTM E-300-86 Same as Demineralized Water HFPO, HFPO-DAF, COF2, & Fluoroether E-1 HFPO-DA SW-846 Method 8260B (Reaction Products) EPA Method 537
Chemours TO DE Test Report 30-Mar-21 18 Focus Project No. P-001446 Table 3-1. Thermal Oxidizer Performance Test Sampling and Analysis Sample Name Sampling Location/ Access Sampling EquipmentSampling Reference Method 1 Sample Size/Frequency- Target Analyte(s) Analytical Reference Method 2 Stage 4 Purge Tap on line 50-100 mL Plastic Graduated Cylinder; 60 mL HDPE Sample Bottles ASTM E-300-86 Same as Demineralized Water HFPO, HFPO-DAF, COF2, & Fluoroether E-1 HFPO-DA SW846 Method 8260B (Reaction Products) EPA Method 537 Notes: 1 Reference Sampling Method Sources: “ASTM” refers to American Society for Testing Materials, Annual Book of ASTM Standards, Annual Series “SW-846" refers to Test Methods for Evaluating Solid Waste, Third Edition, November 1986, and Updates. “EPA Method" refers to New Source Performance Standards, Test Methods and Procedures, Appendix A, 40 CFR 60. 2 Reference Analysis Methods Sources: • Modified Method 18 – “Measurement of Gaseous Organic Compound Emissions by Gas Chromatography.” EPA 40 CFR Part 60, Appendix A. • Method 0010 – “Modified Method 5 Sampling Train”. Taken from Test Methods for Evaluating Solid Waste: Physical/Chemical Methods Compendium, SW-846, Third Edition, September 1986 and its updates, USEPA, OSWER, Washington, D.C. 20460. • Method 5, Appendix A, Test Methods and Procedures, New Source Performance Standards, 40 CFR 60. • Method 8260B – “Volatile Organic Compounds by Gas Chromatography/Mass Spectrometry (GC/MS)”. Taken from Test Methods for Evaluating Solid Waste: Physical/Chemical Methods Compendium, SW-846, Third Edition, September 1986 and its updates, USEPA, OSWER, Washington, D.C. 20460. • Method 3542A – “Extraction of Semivolatile Analytes Collected Using Method 0010 ("Modified Method 5 Sampling Train")”. Taken from Test Methods for Evaluating Solid Waste: Physical/Chemical Methods Compendium, SW-846, Third Edition, September 1986 and its updates, USEPA, OSWER, Washington, D.C. 20460. • Method 537 – “Determination of Selected Perfluorinated Alkyl Acids In Drinking Water By Solid Phase Extraction and Liquid Chromatography/Tandem Mass Spectrometry (LC/MS/MS)”, Version 1.1, September 2009, EPA/600/R-08/092.
Chemours TO DE Test Report 30-Mar-21 19 Focus Project No. P-001446 Table 3-1. Thermal Oxidizer Performance Test Sampling and Analysis 3 The exact volume of gas sampled will depend on the isokinetic sampling rate. 4 Isokinetic sampling trains include: • Sampling traverse points determined in accordance with EPA Method 1. • Performing stack gas velocity, pressure and temperature profile measurement for each sampling location (EPA Method 2) • Oxygen and carbon dioxide concentrations measured to determine stack gas molecular weight (EPA Method 3A) • Determining the moisture content of the stack gas for each sampling train sample (EPA Method 4). 5 Two sample portions of these process streams are collected at each sampling interval: • For samples receiving the HFPO, HFPO-DAF, COF2, and Fluoroether E-1 analyses, a graduated cylinder was used to measure a 40 mL aliquot of the collected material and transfer it to a 60 mL HDPE bottle containing methanol. The lid was placed on the sample bottle and sealed. The methanol reacts with HFPO, HFPO-DAF, and COF2 under these conditions to form derivative products that are evaluated by the laboratory. . The grab portions of these samples were composited in the laboratory to provide a single representative result for each test run. • For the HFPO-DA analysis sample, a 100 ml aliquot of the collected material was placed into a 1000 ml HDPE bottle. The lid was placed on the sample bottle and sealed. Each additional aliquot was added to the bottle to build a field composite of the process sample. The laboratory analyzed the composited sample to provide a single representative result for each test run. The different sample portions are labeled to distinguish between those receiving analysis for the HFPO, HFPO-DAF, COF2, and Fluoroether E-1, and those receiving analysis for HFPO-DA. The final number of discrete sample aliquot portions collected was dependent on the final run duration.

Chemours TO DE Test Report 30-Mar-21 20 Focus Project No. P-001446

Table 3-2. Thermal Oxidizer Performance Test Sampling Dates and Times
Run No.: Run 1 Run 2 Run 3
Date: 26-Jan-21 27-Jan-21 28-Jan-21
Start: 11:15 09:00 08:40
Finish: 14:31 12:11 11:58
Duration: 3:16 3:11 3:18

Table 3-3. Thermal Oxidizer Destruction Efficiency Test Operating Data
Parameter Units Permit Statistic
Run
1
Run
2
Run
3 Average
Monomer Waste Gas lb/hr NA Average 429.3 430.6 448.9 436.3
Maximum 502.5 506.7 569.3 526.2
Minimum 376.6 374.3 343.6 364.8
Std Dev 33.9 32.1 56.9 41.0
Polymer Waste Gas lb/hr NA Average 186.4 184.5 191.3 187.4
Maximum 192.0 188.0 195.5 191.8
Minimum 177.9 180.0 186.8 181.6
Std Dev 2.8 1.7 1.9 2.1
Total Waste Gas lb/hr <2,500 Average 615.8 615.0 640.2 623.7
Maximum 689.1 689.5 758.2 712.3
Minimum 564.8 557.3 536.0 552.7
Std Dev 33.3 32.1 57.2 40.8
Combustion Temperature deg F >1,800 Average 2,012 2,013 2,012 2,012
Maximum 2,015 2,015 2,015 2,015
Minimum 2,008 2,010 2,007 2,009
Std Dev 1 1 2 2
Scrubber Flow Rate gpm >40 Average 88.2 88.2 88.2 88.2
Maximum 88.8 88.7 88.6 88.7
Minimum 87.8 87.7 87.7 87.7
Std Dev 0.2 0.2 0.2 0.2
Scrubber pH SU >7.1 Average 8.17 7.94 7.99 8.04
Maximum 8.20 7.97 8.11 8.09
Minimum 8.13 7.92 7.92 7.99
Std Dev 0.02 0.01 0.05 0.03

Chemours TO DE Test Report 30-Mar-21 21 Focus Project No. P-001446
4.0 TEST RESULTS
4.1 TEST DATA REDUCTION BASIS
The strategy for the determination of the PFAS target analyte feed rates and their emissions evaluation
are conducted to provide the most conservative assessment of the thermal oxidizer performance.
Specifically:
• Calculation of PFAS target analyte feed rates use zero (0) for laboratory non-detect (ND)
values determined from the waste gas line Modified Method 18 sampling and analyses. No
feed rate credit or contribution is taken for constituents below the sampling and analysis
measurement limits.
• The stack gas ND values represent the quantitative limits of the sampling and analytical
measurements under the test conditions. Actual emissions are not assumed to be zero (0),
but are assigned the reporting limit (RL) value for the method. The Modified Method 18
sampling train includes seven (7) impingers in-series that are recovered and analyzed
separately. The calculation of PFAS Modified Method 18 measured stack emission rates is
based on the RL for the first in-series impinger when all seven (7) impingers are ND for a
target analyte. For any impingers with positive results for a specific analyte, the detected
value is used and summed with the RL for any preceding impingers in-series and the RL of
the last ND impinger in-series for the analyte.
• The Modified Method M0010 measured stack emission rates are based on separate analysis
of three (3) sampling train fractions [front-half composite (FH), back-half composite (BH), and
the combined impinger contents and rinses composite]. During this test program, HFPO-DA
was detected in all three (3) sampling fractions during all three (3) sampling runs. Therefore,
the calculation of HFPO-DA Modified Method 0010 measured stack emission rates is based
on the sum of all three (3) analysis fraction detected values. The breakthrough XAD-2 resin
analyses serve as quality control (QC) indicators and are excluded from the HFPO-DA
emissions determinations.

The balance of Section 4.0 details how the test data were reduced to determine thermal oxidizer PFAS
DE performance.
4.2 WASTE GAS CHARACTERIZATION AND TARGET PFAS COMPOUND FEED RATES
The waste gas feed lines were sampled using the Modified Method 18 sampling train. Tables 4-1 and 4-2
summarize the analyses of the polymer and monomer waste gas feed lines. Tables 4-3 and 4-4
summarize the feed rates of the target PFAS compounds. The detailed waste gas feed line sampling
data are included in Source Emissions Testing of a Thermal Oxidizer and Scrubber System Stack, The
Chemours Company – Fayetteville, North Carolina, Ramboll, March 2021 included as an attachment to
this test report. Please note that a zero “0” was applied for calculations used for sample fractions that
were reported by the laboratory as non-detect (ND).
The waste gas feed rates to the thermal oxidizer are measured by mass flow meters. To determine the
target compound feed rates, the waste gas feed sampling and analysis data were reduced to yield mass
of target compound per total mass feed.

Chemours TO DE Test Report 30-Mar-21 22 Focus Project No. P-001446
Please refer to Tables 4-1 and 4-2. Each of the waste gas feed line sampling train fraction mass
concentrations for a target analyte were added together to provide the total mass of each target
compound during a test run. The compound mass totals were determined from sum of the individual
impinger analyses:
CTOTi = ΣCNi
Where: CTOTi = Total mass of individual target compound for a test run,
CNi = Individual mass results of each target compound.

The total mass of all target PFAS compounds captured during a test run was determined from the sum of
the individual target PFAS compounds:
CPFAS = ΣCTOTi
Where: CPFAS = Total mass of target PFAS compounds
CTOTi = Total mass of each target compound.

Please refer to Tables 4-3 and 4-4. From the Modified Method 18 sampling train recovery data, the total
mass of waste gas vapors condensed was determined from the sum of the changes in the impinger
masses:
ΔIMTOT = ΣΔIMN
Where: ΔIMTOT = Total impinger mass change
ΔIMN = Individual impinger mass changes.
From the Modified Method 18 sampling train dry gas metering system data, the mass of dry gas sampled
was determined:
DGM = VM*DGMC*(TS/TM)*[(PB)/(PS)]*MWG/MVSTP
Where: DGM = Dry gas mass
VM = Dry gas meter measured volume
DGMC = Dry gas meter coefficient
TS = Standard temperature in oR or oK

Chemours TO DE Test Report 30-Mar-21 23 Focus Project No. P-001446
TM = Dry gas meter temperature in oR or oK
PB = Barometric pressure
PS = Standard pressure
MWG = Dry gas molecular weight
MV = Molar volume (volume per mole of gas at STP)
STP = Standard temperature and pressure.
Tables 4-3 and 4-4 show the reduced sampled volumes from the previously referenced Ramboll report for
the waste gas feed line Modified Method 18 sampling trains in dry standard liters. The waste gas feed
line dry gas fraction was assumed to be 100% nitrogen and was assigned a molecular weight of 28 amu.
The mass of dry gas sampled was determined by multiplying the measured dry gas standard sample
volume by the molecular weight of nitrogen and dividing by the molar volume at standard temperature
and pressure, 24.055 liter/gram mole. The total mass sampled from the waste gas feed line is the sum of
dry gas total mass and the impinger mass gain:
MTOT = DGM + ΔIMTOT
Where: MTOT = Total organic vapor and dry gas mass sampled
ΔIMTOT = Total impinger mass change
DGM = Dry gas mass.
The mass fraction of the target PFAS compounds per total mass feed was determined dividing total mass
of target PFAS compounds captured by the total mass sampled:
FCPFAS = CPFAS/MTOT
Where: FCPFAS = Feed concentration of target PFAS compounds
in mass/total mass sampled

CPFAS = Total mass of target compound
MTOT = Total mass of organic vapor and dry gas mass sampled.
The total PFAS target compound mass feed rate was determined by multiplying the calculated mass
fraction of total PFAS target compounds by the mass feed rate measured by the thermal oxidizer mass
flow meters:
FRPFAS = FCCPFAS ∗ MF
Where: FRPFAS = Mass feed rate of target compound
FCCPFAS = Feed concentration of target compound in mass/total mass
MF = Mass feed rate measured by the mass flow meter.

Chemours TO DE Test Report 30-Mar-21 24 Focus Project No. P-001446
4.3 TARGET PFAS COMPOUND STACK EMISSION RATES
Two (2) sampling trains were used to measure the stack emission rates of the target PFAS compounds:
• Modified Method 0010 for HFPO-DA, and
• Modified Method 18 for HFPO, HFPO-DAF, COF2, and Fluoroether E-1.

The detailed stack gas sampling data and laboratory analysis reports are included in Appendixes B and
C, respectively of the previously referenced Ramboll report.
4.3.1 Modified Method 0010 Measured Emissions
Please refer to Table 4-5. From the Modified Method 0010 sampling train fraction analysis, the total mass
of the target compound was determined from sum of the individual fraction composite analyses:
CTOT = CFH + CBH + CIMP
Where: CTOT = Total mass of target compound
CFH = Mass of target compound in front half fraction
(probe, nozzle, and front half solvent rinses and particulate filter)

CBH = Mass of target compound in back half fraction
(XAD-2 resin, and back half and impinger solvent rinses)

CIMP = Mass of target compound in impinger fraction
(condensate and impinger liquid).

From the Modified Method 0010 sampling train dry gas metering system data, the volume of dry gas
sampled was determined:
DGV = VM*DGMC*(TS/TM)*[(PB+ΔH)/(PS)]
Where: DGV = Dry gas volume sampled at standard temperature and pressure
VM = Dry gas meter measured volume
DGMC = Dry gas meter coefficient
TS = Standard temperature in oR or oK
TM = Dry gas meter temperature in oR or oK
PB = Barometric pressure
ΔH = Delta H sampling pressure (vacuum)
PS = Standard pressure.

Chemours TO DE Test Report 30-Mar-21 25 Focus Project No. P-001446
The details of the stack gas Modified Method 0010 sampled volume determinations are included in the
previously referenced Ramboll report. The sampled stack gas volumes from the Ramboll report reduced
to standard conditions are presented in Table 4-5. The stack gas concentration of the HFPO-DA was
determined by dividing the total mass of HFPO-DA by the sampled volume:
ECC = CTOT/DGV
Where: ECC = Emission concentration of target compound in mass/dry volume
CTOT = Total mass of target compound
DGV = Dry gas volume sampled at standard temperature and pressure.
The stack flow rates from the Ramboll report reduced to standard conditions are presented in Table 4-5.
The emission rate of the HFPO-DA was determined by multiplying the stack gas concentration by the
stack flow rate:
ERC = ECC ∗ SFDG
Where: ERC = Emission rate of target compound
ECC = Emission concentration of target compound in mass/dry volume
SFDG = Dry gas stack flow rate at standard temperature and pressure
(as determined from Method 0010 data)
(Method 1, 2, 3A, and 4 data).
4.3.2 Modified Method 18 Measured Emissions
Please refer to Table 4-6. From the Modified Method 18 sampling train fraction analysis, the total mass of
each target compound was determined from sum of the individual impinger analyses:
CTOT = ΣCN
Where: CTOT = Total mass of target compound
CN = Individual impinger mass analysis results.

Analysis results for three of the four (3 of 4) target compounds measured using Modified Method 18 were
non-detect (ND). As noted in Section 2.3.5.2, only the reporting limit (RL) for the first impinger was used
to calculate PFAS emissions results for these three compounds. The Run 2 and Run 3 Modified Method
18 were analysis results for HFPO were also non-detect in all seven (7) impingers. For these two test
runs, only the reporting limit for the first impinger was used to calculate HFPO emissions. As noted in
Section 2.3.5.2, positive results for HFPO were exhibited just above the reporting limit in Impingers 1, 3,
4, and 6. Therefore, for Run 1 the positive results for these four (4) impingers and the reporting limits for
Impingers 2, 5, and 7 were summed to calculate HFPO emissions for Run 1.

Chemours TO DE Test Report 30-Mar-21 26 Focus Project No. P-001446
From the Modified Method 18 sampling train dry gas metering system data, the volume of dry gas
sampled was determined:
DGV = VM*DGMC*(TS/TM)*[(PB+ΔH)/(PS)]
Where: DGV = Dry gas volume sampled at standard temperature and pressure
VM = Dry gas meter measured volume
DGMC = Dry gas meter coefficient
TS = Standard temperature in oR or oK
TM = Dry gas meter temperature in oR or oK
PB = Barometric pressure
ΔH = Delta H sampling pressure (vacuum)
PS = Standard pressure.
PS = Standard pressure.
The details of the stack gas Modified Method 18 sampled volume determinations are included in the
previously referenced Ramboll report. The sampled stack gas volumes from the Ramboll report reduced
to standard conditions are presented in Table 4-6. The stack gas concentration of target compounds was
determined by dividing the total mass of the target compounds by the sampled volume:
ECC = CTOT/DGV
Where: ECC = Emission concentration of target compounds in mass/dry volume
CTOT = Total impinger mass of target compounds
DGV = Dry gas volume sampled at standard temperature and pressure.
Please refer to Table 4-7. The emission rate of the target compounds was determined by multiplying the
stack gas concentration by the stack flow rate:
ERC = ECC ∗ SFDG
Where: ERC = Emission rate of target compound
ECC = Emission concentration of target compound in mass/dry volume
SFDG = Dry gas stack flow rate at standard temperature and pressure
(as determined from Method 0010 data)
(Method 1, 2, 3A, and 4 data).

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4.4 TOTAL PFAS DESTRUCTION EFFICIENCY
Please refer to Table 4-8, “Total PFAS” is the arithmetic sum of HFPO, HFPO-DA, HFPO-DAF, COF2,
and Fluoroether E-1. The total PFAS destruction efficiency (DE) was calculated by dividing the difference
of the total PFAS feed rate and the total PFAS emission rate by the total PFAS feed rate:
DE = (FR-ER)/FR *100%

Where: DE = Total PFAS destruction efficiency, percent (%)
FR = Total PFAS mass feed rate
ER = Total PFAS mass emission rate.
The total PFAS DE performance results presented in Table 4-8 demonstrate that the thermal oxidizer
controls all PFAS at an efficiency greater than 99.99%.

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Table 4-1. Thermal Oxidizer Monomer Tank Feed (Line #1) Summary Analyses
Target Compound Train Fraction Units Run 1 Run 2 Run 3
COF2 Impinger 1 ug 47,900,000 49,000,000 52,900,000
COF2 Impinger 2 ug 2,480,000 1,060,000 3,100,000
COF2 Impinger 3 ug 103,000 124,000 176,000
COF2 Impinger 4 ug 5,910 6,640 12,500
COF2 Impinger 5 ug ND ND ND
COF2 Impinger 6 ug ND ND ND
COF2 Total ug 50,488,910 50,190,640 56,188,500
HFPO-DAF Impinger 1 ug ND ND ND
HFPO-DAF Impinger 2 ug ND ND ND
HFPO-DAF Impinger 3 ug ND ND ND
HFPO-DAF Impinger 4 ug ND ND ND
HFPO-DAF Impinger 5 ug ND ND ND
HFPO-DAF Impinger 6 ug ND ND ND
HFPO-DAF Total ug 00 0
HFPO Impinger 1 ug 207,000 84,000 277,000
HFPO Impinger 2 ug 334,000 126,000 401,000
HFPO Impinger 3 ug 340,000 232,000 292,000
HFPO Impinger 4 ug 266,000 197,000 366,000
HFPO Impinger 5 ug 220,000 162,000 263,000
HFPO Impinger 6 ug 174,000 111,000 170,000
HFPO Total ug 1,541,000 912,000 1,769,000
Fluoroether E-1 Impinger 1 ug ND ND ND
Fluoroether E-1 Impinger 2 ug ND ND ND
Fluoroether E-1 Impinger 3 ug ND ND ND
Fluoroether E-1 Impinger 4 ug ND ND ND
Fluoroether E-1 Impinger 5 ug ND ND ND
Fluoroether E-1 Impinger 6 ug ND ND ND
Fluoroether E-1 Total ug 00 0
HFPO-DA Impinger 1 ug 1,730,000 2,560,000 2,360,000
HFPO-DA Impinger 2 ug 292,000 131,000 407,000
HFPO-DA Impinger 3 ug 18,300 50,900 36,900
HFPO-DA Impinger 4 ug 6,040 18,100 13,100
HFPO-DA Impinger 5 ug 2,520 5,960 6,330
HFPO-DA Impinger 6 ug 1,320 2,430 2,760
HFPO-DA Total ug 2,050,180 2,768,390 2,826,090
Total Target PFAS Mass grams 54.08 53.87 60.78

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Table 4-2. Thermal Oxidizer Polymer Tank Feed (Line #2) Summary Analyses
Target Compound Train Fraction Units Run 1 Run 2 Run 3
COF2 Impinger 1 ug 600 161 1,140
COF2 Impinger 2 ug ND ND ND
COF2 Impinger 3 ug ND ND ND
COF2 Impinger 4 ug ND ND ND
COF2 Impinger 5 ug ND ND ND
COF2 Impinger 6 ug ND ND ND
COF2 Total ug 600 161 1,140
HFPO-DAF Impinger 1 ug 74.9 83.6 120
HFPO-DAF Impinger 2 ug 22.8 41.5 74.2
HFPO-DAF Impinger 3 ug 13.2 ND 40.3
HFPO-DAF Impinger 4 ug ND ND 13.2
HFPO-DAF Impinger 5 ug ND ND ND
HFPO-DAF Impinger 6 ug ND ND ND
HFPO-DAF Total ug 111 125 248
HFPO Impinger 1 ug ND ND ND
HFPO Impinger 2 ug ND ND ND
HFPO Impinger 3 ug ND ND ND
HFPO Impinger 4 ug ND ND ND
HFPO Impinger 5 ug ND ND ND
HFPO Impinger 6 ug ND ND ND
HFPO Total ug 00 0
Fluoroether E-1 Impinger 1 ug 468 499 1,350
Fluoroether E-1 Impinger 2 ug 40.8 38.8 127
Fluoroether E-1 Impinger 3 ug 5.56 ND 23.0
Fluoroether E-1 Impinger 4 ug ND ND ND
Fluoroether E-1 Impinger 5 ug ND ND ND
Fluoroether E-1 Impinger 6 ug ND ND ND
Fluoroether E-1 Total ug 514 538 1,500
HFPO-DA Impinger 1 ug 50,200 76,900 109,000
HFPO-DA Impinger 2 ug 15,300 32,900 57,900
HFPO-DA Impinger 3 ug 10,600 3,940 25,600
HFPO-DA Impinger 4 ug 3,840 273 8,540
HFPO-DA Impinger 5 ug 827 50.3 1,560
HFPO-DA Impinger 6 ug 154 ND 202
HFPO-DA Total ug 80,921 114,063 202,802
Total Target PFAS Mass grams 0.08215 0.1149 0.2057

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Table 4-3. Thermal Oxidizer Monomer Tank (Line #1) Sampling Results and Feed Rates
Parameter Units Run 1 Run 2 Run 3
Net Inlet Condensed Mass grams 117.4 71.0 126.8
Speciated Compounds in Condensed Mass
Total COF2 ug 50,488,910 50,190,640 56,188,500
Total HFPO-DAF ug 0 0 0
Total HFPO ug 1,541,000 912,000 1,769,000
Total Fluoroether E-1 ug 0 0 0
Total HFPO-DA ug2,050,180 2,768,390 2,826,090
Target PFAS Sample Mass grams 54.08 53.87 60.78
Total Dry Gas and Condensed Mass Sampled
Sampled Dry Gas Volume (@ 20oC, 1 atm)Liters 119.383 115.393 125.456
Sampled Dry Gas Mass (24.055 L/gmol, MW=28)grams 138.962 134.317 146.031
Total Mass Sampled (Condensed + Dry Gas)grams 256.362 205.317 272.831
Constituent Concentrations in Total Sampled Mass
Total COF2 g/g flow 2.0E-01 2.4E-01 2.1E-01
Total HFPO-DAF g/g flow 0.0E+00 0.0E+00 0.0E+00
Total HFPO g/g flow 6.0E-03 4.4E-03 6.5E-03
Total Fluoroether E-1 g/g flow 0.0E+00 0.0E+00 0.0E+00
Total HFPO-DA g/g flow 8.0E-03 1.3E-02 1.0E-02
Total Target PFAS Characterized g/g flow 2.1E-01 2.6E-01 2.2E-01
Calculated Constituent Feed Rates
Monomer Tank Gas Flow (estimate) lb/hr 429.3 430.6 448.9
Monomer Tank Gas Flow kg/hr 194.7 195.3 203.6
Total COF2 g/hr 38,354 47,743 41,933
Total HFPO-DAF g/hr 0 0 0
Total HFPO g/hr 1,171 868 1,320
Total Fluoroether E-1 g/hr 0 0 0
Total HFPO-DA g/hr 1,557.40 2,633.38 2,109.08
Total Target PFAS Feed g/hr 41,082 51,244 45,362

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Table 4-4. Thermal Oxidizer Polymer Tank (Line # 2) Sampling Results and Feed Rates
Parameter Units Run 1 Run 2 Run 3
Net Inlet Condensed Mass grams -29.6 -2.4 0.6
Speciated Compounds in Condensed Mass
Total COF2 ug 600 161 1,140
Total HFPO-DAF ug 111 125 248
Total HFPO ug 00 0
Total Fluoroether E-1 ug 514 538 1,500
Total HFPO-DA ug80,921 114,063 202,802
Target PFAS Sample Mass grams 0.08215 0.11489 0.20569
Total Dry Gas and Condensed Mass Sampled
Sampled Dry Gas Volume (@ 20oC, 1 atm)Liters 120.866 116.382 126.021
Sampled Dry Gas Mass (24.055 L/gmol, MW=28)grams 140.688 135.468 146.689
Total Mass Sampled (Condensed + Dry Gas)grams 111.088 133.068 147.289
Constituent Concentrations in Total Sampled Mass
Total COF2 g/g flow 5.4E-06 1.2E-06 7.7E-06
Total HFPO-DAF g/g flow 1.0E-06 9.4E-07 1.7E-06
Total HFPO g/g flow 0.0E+00 0.0E+00 0.0E+00
Total Fluoroether E-1 g/g flow 4.6E-06 4.0E-06 1.0E-05
Total HFPO-DA g/g flow 7.3E-04 8.6E-04 1.4E-03
Total Target PFAS Characterized g/g flow 7.4E-04 8.6E-04 1.4E-03
Calculated Constituent Feed Rates
Polymer Tank Gas Flow lb/hr 186.4 184.5 191.3
Polymer Tank Gas Flow kg/hr 84.6 83.7 86.8
Total COF2 g/hr 0.457 0.101 0.672
Total HFPO-DAF g/hr 0.084 0.0787 0.146
Total HFPO g/hr 0.000 0.000 0.000
Total Fluoroether E-1 g/hr 0.392 0.338 0.884
Total HFPO-DA g/hr 61.6 71.7 119.5
Total Target PFAS Feed g/hr 62.5 72.2 121.2

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Table 4-5. Thermal Oxidizer Modified Method 0010 Emissions Results
Parameter Units Run 1 Run 2 Run 3
Stack Flow dscfm 5,894 6,044 6,058
Method 0010 Sampled Volume dscf 158.722 164.908 171.554
Method 0010 Front Half HFPO-DA ug0.0739 0.280 0.180
Method 0010 Back Half HFPO-DA ug0.0246 0.429 0.249
Method 0010 Impingers HFPO-DA ug0.0583 0.0888 0.0972
Method 0010 Breakthrough XAD HFPO-DA
(Breakthrough Indicator Only) ug 0.00920 0.0164 0.00717
Method 0010 Train Total HFPO-DA
(Excludes Breakthrough XAD) ug 0.157 0.798 0.526
Method 0010 HFPO-DA Emissions g/hr 0.000349 0.00175 0.00111

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Table 4-6. Thermal Oxidizer Stack Modified Method 18 Sample Analyses
Parameter Units Run 1 Run 2 Run 3
Speciated Compounds in Impingers
COF2, Impinger 1 ug < 4.07 < 2.06 < 2.12
COF2, Impinger 2 ug < 2.32 < 2.70 < 2.10
COF2, Impinger 3 ug < 2.37 < 2.24 < 2.24
COF2, Impinger 4 ug < 2.04 < 2.40 < 2.02
COF2, Impinger 5 ug < 2.42 < 2.32 < 1.98
COF2, Impinger 6 ug < 2.54 < 2.58 < 2.10
COF2, Impinger 7 ug < 2.08 < 2.48 < 2.31
Total COF2 including ND Values ug < 17.8 < 16.8 < 14.9
Total COF2 only Impinger 1 ug < 4.07 < 2.06 < 2.12
Total COF2 only Impinger 1 or Positive Results ug < 4.07 < 2.06 < 2.12
HFPO-DAF, Impinger 1 ug < 1.34 < 0.679 < 0.698
HFPO-DAF, Impinger 2 ug < 0.764 < 0.890 < 0.690
HFPO-DAF, Impinger 3 ug < 0.779 < 0.738 < 0.739
HFPO-DAF, Impinger 4 ug < 0.670 < 0.788 < 0.663
HFPO-DAF, Impinger 5 ug < 0.797 < 0.762 < 0.652
HFPO-DAF, Impinger 6 ug < 0.837 < 0.849 < 0.692
HFPO-DAF, Impinger 7 ug < 0.685 < 0.818 < 0.760
Total HFPO-DAF including ND Values ug < 5.872 < 5.524 < 4.894
Total HFPO-DAF only Impinger 1 ug < 1.340 < 0.679 < 0.698
Total HFPO-DAF only Impinger 1 or Positive Results ug < 1.340 < 0.679 < 0.698
HFPO, Impinger 1 ug 0.0794 < 0.0307 < 0.0315
HFPO, Impinger 2 ug < 0.0346 < 0.0403 < 0.0313
HFPO, Impinger 3 ug 0.0495 < 0.0334 < 0.0335
HFPO, Impinger 4 ug 0.0328 < 0.0357 < 0.0300
HFPO, Impinger 5 ug < 0.0361 < 0.0345 < 0.0295
HFPO, Impinger 6 ug 0.0415 < 0.0384 < 0.0314
HFPO, Impinger 7 ug < 0.0310 < 0.0370 < 0.0344
Total HFPO including ND Values ug < 0.305 < 0.2500 < 0.2216
Total HFPO only Impinger 1 ug NA < 0.0307 < 0.0315
Total HFPO only Impinger 1 or Positive Results ug 0.203 < 0.0307 < 0.0315
Fluoroether E-1, Impinger 1 ug < 0.0694 < 0.0352 < 0.0361
Fluoroether E-1, Impinger 2 ug < 0.0396 < 0.0461 < 0.0358
Fluoroether E-1, Impinger 3 ug < 0.0404 < 0.0382 < 0.0383
Fluoroether E-1, Impinger 4 ug < 0.0347 < 0.0409 < 0.0343
Fluoroether E-1, Impinger 5 ug < 0.0413 < 0.0395 < 0.0338
Fluoroether E-1, Impinger 6 ug < 0.0434 < 0.0440 < 0.0359
Fluoroether E-1, Impinger 7 ug < 0.0355 < 0.0424 < 0.0394
Total Fluoroether E-1 including ND Values ug < 0.304 < 0.286 < 0.254
Total Fluoroether E-1 only Impinger 1 ug < 0.0694 < 0.0352 < 0.0361
Total Fluoroether E-1 only Impinger 1 or Positive
Results ug < 0.0694 < 0.0352 < 0.0361
Total Characterized Including NDs ug < 24.3 < 22.8 < 20.2
Total Characterized only Impinger 1 ug NA < 2.80 < 2.89
Total Characterized only Impinger 1 or Positive Results ug < 5.68 < 2.80 < 2.89

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Table 4-7. Thermal Oxidizer Modified Method 18 Stack Emissions Results
Parameter Units Run 1 Run 2 Run 3
Sampled Stack Volume dsl 217.086 219.769 223.830
Sampled Stack Volume dscf 6.148 6.224 6.339
Stack Flow dscfm 5,894 6,044 6,058
Total Target PFAS only Impinger 1
or Positive Results ug <5.68 <2.80 < 2.89
Total Characterized only
Impinger 1 or Positive Results g/hr < 0.3269 < 0.1634 < 0.1655

Table 4-8. Thermal Oxidizer Total PFAS Destruction Efficiency
Parameter Units Run 1 Run 2 Run 3
Monomer Feed Total Target PFAS Inlet by
Modified Method 18 (ND=0) g/hr 41,082 51,244 45,362
Polymer Feed Total Target PFAS Inlet by
Modified Method 18 (ND=0) g/hr 63 72 121
Total Target PFAS Inlet by
Modified Method 18 (ND=0) g/hr 41,144 51,316 45,483
Outlet HFPO-DA by
Modified Method 0010 g/hr 0.000349 0.00175 0.00111
Outlet Other Target PFAS by Modified Method
18 g/hr < 0.327 < 0.163 < 0.165
Total Target PFAS Outlet g/hr < 0.327 < 0.165 < 0.167
Total Target PFAS DE % > 99.99920% > 99.99968% > 99.99963%
Average Target PFAS DE % > 99.99951%

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5.0 QUALITY CONTROL
5.1 WASTE GAS SAMPLING
The waste gas constituents and their concentrations vary based on the product(s) being manufactured at
any particular time. Waste gas sampling was performed using the Modified Method 18 sampling train that
was developed for the Chemours Fayetteville Works test program. Both waste gas feed lines were
sampled independently to determine the concentrations of the five (5) target PFAS compounds. The
waste gas sampling was performed at a constant sampling rate from the start of stack gas sampling and
through completion of the stack gas sampling. The samples obtained represent the average composition
during each test run. The sampling and analysis data were reduced to yield mass of target analyte per
total mass of waste gas in each feed line. This information and the respective waste gas feed line mass
feed rate data were used to determine inlet feed rates of the target PFAS compounds. The following
sections examine the quality of the waste gas feed characterization results and their associated impacts
on the measurement of the thermal oxidizer DE performance.
5.1.1 Monomer Waste Gas Sampling
During the test, Vinyl Ethers North (VEN) was producing PSEPVE. COF2, HFPO, and HFPO-DA were
present in the monomer waste gas feed (Line #1), while no HFPO-DAF or Fluoroether E-1 were
measured in these samples. Figures 5-1, 5-2, and 5-3 graphically show the relative loadings of each of
the three (3) detected target compounds in the six (6) Modified Method 18 impingers.
COF2 and HFPO-DA are primarily captured in the first two impingers. COF2 readily reacts with methanol.
During all three (3) runs, no COF2 is detected after the fourth impinger. The capture of HFPO-DA is
assumed to occur via condensation and dissolution, and HFPO-DA does not react with methanol. The
distribution of HFPO-DA was detected in all six (6) impingers with >99% of the train total being captured
in Impingers 1-3. These data show COF2 and HFPO-DA are being captured with a high degree of
efficiency.
HFPO was detected in all six (6) impingers distributed at comparable levels throughout. Capture of
HFPO is dependent on both condensation and chemical reaction. These data show HFPO is being
detected at a lesser degree of efficiency, thus its measured concentration and actual feed rate is higher
than is being measured. A low bias to this concentration translates to a low bias in the DE determination.
Therefore, a higher concentration determined for HFPO for this feed line would result in a higher DE
demonstration. Despite a low bias in feed rate measurement, all PFAS DE is demonstrated to exceed
99.99% efficiency.

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5.1.2 Polymer Waste Gas Sampling
During the test, Polymers was running a 920 SR polymer campaign. HFPO-DAF, COF2, Fluoroether E-1,
and HFPO-DA were present in the polymer waste gas feed (Line #2), but no HFPO was detected.
Figures 5-4, 5-5, 5-6, and 5-7 graphically show the relative loadings of each of the four (4) detected target
compounds in the six (6) Modified Method 18 impingers.
Except for Run 3, HFPO-DAF was detected in the first three (3) impingers with >90% of the train total
being captured in Impingers 1-3; about 10% of the Run 3 capture was in Impinger 4. All COF2 is captured
in the first two (2) impingers with none detected after the second impinger. HFPO-DA was detected in
five of six (5 of 6) impingers during Run 1 and Run 3, and all six (6) impingers during Run 2. All
Fluoroether E-1 is captured in the first three (3) impingers with none detected after the third impinger.
These data show HFPO-DAF, COF2, HFPO-DA, and Fluoroether E-1 are being captured with a high
degree of efficiency.
5.2 WASTE GAS ANALYSES
Tables 5-1 through 5-4 summarize the surrogate spike compound recoveries for the waste gas analyses.
5.2.1 Monomer Waste Gas Analyses
Please refer to Table 5-1 for the monomer waste gas (Line # 1) SW-846 Method 8260B analysis
surrogate spike recoveries. For the SW-846 Method 8260B (volatile organic) analyses for COF2, HFPO,
HFPO-DAF, and Fluoroether E-1, surrogate spike recoveries ranged from 87-103%. Four (4) standard
surrogate spike compounds spanning the volatile range were reported. Two of the samples required
dilution and re-analysis to accurately quantify the specific target analytes. The narrow range and high
degree of surrogate recoveries represent a relatively high precision and accuracy with regard to the
measurements of these target analytes in the high concentration waste gas samples.
Table 5-2 refers to the monomer waste gas (Line # 1) EPA Method 537 analysis isotope dilution internal
standard (IDIS) spike recoveries related to the determination of HFPO-DA. The IDIS spike recoveries of
the labeled HFPO-DA (13C3 HFPO-DA) ranged from 55-96%. All recoveries were well within the target
range of 25-150%. The data are assumed to appropriately accurate, and useable for the intended
purposes.
5.2.2 Polymer Waste Gas Analyses
The analysis results show the concentrations of target compounds in the polymer gas (Feed Line #2)
were nominally four (4) orders of magnitude lower than in Feed Line #1. Please refer to Table 5-3 for the
polymer waste gas (Line # 2) SW-846 Method 8260B analysis surrogate spike recoveries.
For the SW-846 Method 8260B (volatile organic) analyses for COF2, COF2, HFPO, HFPO-DAF, and
Fluoroether E-1 surrogate spike recoveries ranged from 88-103%. Four (4) standard surrogate spike

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compounds spanning the volatile range are reported. The narrow range and high degree of surrogate
recoveries represent a relatively high degree of precision and accuracy with regard to the measurements
of these target analytes in the high concentration waste gas samples.
Table 5-4 displays the polymer waste gas (Line # 2) EPA Method 537 analysis IDIS spike recoveries.
The IDIS spike recoveries of the isotopically-labeled HFPO-DA (13C3 HFPO-DA) ranged from 100-118%.
The data are assumed to appropriately accurate, and useable for the intended purposes.
5.3 STACK GAS SAMPLING
Measurement of the stack gas emission rates of the five (5) target PFAS compounds involved two (2)
sampling trains:
• Modified Method 18 for COF2, HFPO, HFPO-DAF, and Fluoroether E-1, and
• Modified Method 0010 for HFPO-DA.

The Modified Method 0010 stack was performed for 180 minutes during each test run to sample a
minimum of three (3) dry standard cubic meters (dscm) of stack gas. The Modified Method 18 sampling
was performed concurrently. The following sections examine the quality of the thermal oxidizer stack gas
emissions sampling and analysis data results, and the associated impacts on the measurement of the
thermal oxidizer DE performance.
5.3.1 Stack Gas Modified Method 18 Results
Please refer to Table 5-5 for the Modified Method 18 analysis surrogate spike recoveries.
For the SW-846 Method 8260B (volatile organic) analyses for COF2, HFPO, HFPO-DAF, and Fluoroether
E-1, surrogate spike recoveries ranged from 86-108% with the target recovery being 50-150%. The stack
gas Modified Method 18 samples were analyzed using selected ion monitoring (SIM) technique to
reduces the detection (reporting) limits to substantially lower levels. For this reason, recoveries of only
the two (2) surrogate compounds associated with the target analytes are reported. Conversely, the
previously discussed waste gas line Modified Method 18 analyses were analyzed at normal Method
8260B levels with all four (4) of the standard surrogate spike compounds spanning the volatile range
being reported. The narrow range and high degree of surrogate recoveries represent a relatively high
degree of both precision and accuracy with regard to the measurements of these target analytes in the
stack gas.
COF2, HFPO-DAF, and Fluoroether E-1 were “non-detect” in all Modified Method 18 sample fractions.
HFPO was “non-detect” in all Run 2 and Run 3 Modified Method 18 sample fractions. The Run 1
Modified Method 18 impingers exhibited detectable levels of HFPO in four of seven (4 of 7) impingers at
slightly more than the reporting limits in all cases. The stack gas Modified Method 18 blank train, proof

Chemours TO DE Test Report 30-Mar-21 38 Focus Project No. P-001446
blank, and reagent blank samples were non-detect for all four target analytes including HFPO. The
HFPO in the Run 1 samples is most likely from an unidentified external source during sampling train
preparation or recovery. The analytical data quality indicators display sufficient accuracy of the low
measurements, and indicate that the data is reliable for demonstrating that the actual DE of the measured
compounds exceeds the reported 99.999%.
5.3.2 Stack Gas Modified Method 0010 Results
Please refer to Table 5-6 for the Modified Method 0010 sampling and analysis surrogate spike recoveries.
For the EPA Method 537 analyses of the Modified Method 0010 sampling train fractions, two (2) types of
surrogate spikes and three (3) isotopically labeled spiking compounds were used:
• Two (2) sampling surrogates applied to the XAD-2 resin before field sampling:
− Isotopically labeled perfluorooctanoic acid (PFOA) (13C8 PFOA)
− Isotopically labeled perfluorooctanesulfonic acid (PFOS) (13C8 PFOS)
• One analysis IDIS, isotopically labeled HFPO (13C3 HFPO-DA) applied to each analytical
fraction during sample preparation for analysis.

The two (2) sampling surrogate compounds applied to the primary XAD-2 resins provide a
comprehensive assessment of the system’s ability to capture and retain the target analyte through all the
sampling and analysis processes. [Note: These sampling surrogate compounds were not applied to the
breakthrough XAD-2 resins.] The analysis IDIS applied to all analytical fractions provides an assessment
of the ability to recover the target analyte through the sample preparation and analysis processes. The
Modified Method 0010 fractions were analyzed using high performance precision liquid
chromatography/tandem mass spectrometry (HPLC/MS/MS).
The recoveries for the two sampling surrogate spike compounds for the Run 1 and Run 2 back-half
samples (XAD-2 resin, and condenser and impinger solvent rinses) ranged from 100-104% for 13C8 PFOA
and 88-89% for 13C8 PFOS. The recoveries for the Run 3 back-half sample were 31% and 20%
respectively for 13C8 PFOA and % for 13C8 PFOS. The target range for these compounds was 50-150%.
The Run 3 recoveries indicate a potential low bias for the test run.
Table 5-6 also shows recoveries for the two (2) sampling surrogate spike compounds in the impinger and
breakthrough XAD-2 fractions. These surrogate compounds are not actually applied to the sample
fractions noted. Analysis data for 13C8 PFOA and 13C8 PFOS in these post XAD-2 resin sample fractions
was obtained to assess if the surrogates applied to the primary XAD-2 resins are being stripped and
travel to the impingers or the second XAD-2 trap during the sample flow through the sampling train. The
values are all zero (0) which demonstrate the sampling surrogate spikes are not traveling within the
sampling train.

Chemours TO DE Test Report 30-Mar-21 39 Focus Project No. P-001446

The recoveries for the IDIS surrogate spike compound ranged from 59-104% for 13C3 HFPO-DA. The
target range was 25-150%. The excellent recoveries demonstrate the ability to recover the target analyte
through the sample preparation and analysis processes.
These analytical data quality indicators for the Modified Method 0010 sampling and analysis indicate that
the data are sufficiently accurate for these very low-level stack gas measurements and that the data are
usable for their intended purpose.
5.3.3 Positive HFPO-DA Results
All the Modified Method 0010 stack gas train fractions exhibited low level positive results for HFPO-DA.
Please refer to Table 5-7. Individual fraction and sampling train total results are all less than one (1)
microgram (ug). Similar HFPO-DA levels were exhibited in the blank train (BT) and proof blank (PB)
analyses. The deionized water reagent blank exhibited a positive result just above the reporting limit.
The methanol reagent blank and XAD-2 resin media checks were non-detect. The positive results appear
to be due to background sources and have no significant impact on the DE performance determinations.
The exact source of the low-level positive HFPO-DA results is unclear. The analysis data perhaps point
to possible sampling train component artifacts, or background. It is not probable that the HFPO-DA in the
samples originated from thermal oxidizer emissions. The potential for HFPO-DA to pass through the
combustion system as HFPO-DA is thermodynamically improbable. Fluoroether E-1 is the thermal
decarboxylation product of HFPO-DA which occurs at approximately 200-250oF. Incomplete combustion
of HFPO-DA could possibly be exhibited as Fluoroether E-1. However, the Modified Method 18 samples
all give non-detect results for Fluoroether E-1 which makes the survival hypothesis seem remote. Other
low-level background HFPO-DA sources are considered probable.
5.4 PROCESS WATER ANALYSES
The demineralized make-up water used in the scrubber system, and the HF acid and Stage 4 purge
streams from the scrubber system were sampled and analyzed for the same five (5) target PFAS
compounds. The analyses are summarized in Table 5-8.
The purpose for the sampling and analyses of the demineralized make-up water samples was to evaluate
possible target analyte contamination introduced to the stack gas samples. The purpose of the acid and
purge samples was to evaluate the possible fate of the target analytes.
Positive results were reported for HFPO-DA in the following samples:
• Run 1 demineralized water sample just above the reporting limit
• Run 2 and Run 3 demineralized water samples both below the reporting limit
• All three HF acid samples, all below the reporting limit, and

Chemours TO DE Test Report 30-Mar-21 40 Focus Project No. P-001446
• Run 3 Stage 4 purge below the reporting limit.

During the DE testing, the demineralized water was introducing HFPO-DA to the combustion gas
scrubbing system. For the reasons stated in the preceding section, the combustion system as a source
of HFPO-DA is improbable. The mass transfer of water to the combustion gas via evaporation in the
scrubbing sections may have a concentrating impact in the liquid phase on any HFPO-DA introduced to
the system via the demineralized water. This concentrating impact would occur primarily in the Catch
Tank with the adiabatic water saturation of the combustion gas. All three HF acid samples (Catch Tank
discharge) exhibited positive results for HFPO-DA. The same demineralized water source is used as
makeup to scrubbing Stage 4 and is a possible source for the positive result exhibited in one of the three
Stage 4 purge samples. These also data indicate possible contribution of HFPO-DA to the Method 0010
sampling train results, but with no impact on HFPO-DA or total PFAS DE determinations.
All process water analysis results were negative for the other four (4) target PFAS compounds.
5.5 OVERALL DATA QUALITY ASSESSMENT
A comprehensive review has been conducted of the thermal oxidizer performance test data quality
indicators. Quality assurance and quality control (QA/QC) measurements indicate the data sets for this
test project are representative of the processes from which they are derived, and that sufficient
measurements have been performed to assess the overall precision and accuracy. The conclusion from
this assessment is all the data are of sufficient quality to be used for their intended purposes.

Chemours TO DE Test Report 30-Mar-21 41 Focus Project No. P-001446
Table 5-1. Monomer Waste Gas Method 8260B Analysis Surrogate Recoveries
Method 8260B Analysis Surrogate Recoveries Run Surrogate Recovery
Sample Fraction No. 1 2 3 4
M- 1375 Monomer Feed Line, MM18, Impinger #1 1 93% 91% 98% 102%
COF2 Exceeded Range; Re-analysis 92% 90% 99% 102%
M- 1376 Monomer Feed Line, MM18, Impinger #2 1 92% 89% 100% 102%
M- 1377 Monomer Feed Line, MM18, Impinger #3 1 92% 90% 99% 102%
M- 1378 Monomer Feed Line, MM18, Impinger #4 1 94% 90% 100% 103%
M- 1379 Monomer Feed Line, MM18, Impinger #5 1 95% 88% 99% 102%
M- 1380 Monomer Feed Line, MM18, Impinger #6 1 93% 87% 100% 102%
M- 1381 Monomer Feed Line, MM18, Impinger #1 2 93% 88% 100% 102%
M- 1382 Monomer Feed Line, MM18, Impinger #2 2 94% 92% 102% 103%
M- 1383 Monomer Feed Line, MM18, Impinger #3 2 91% 91% 101% 102%
M- 1384 Monomer Feed Line, MM18, Impinger #4 2 93% 90% 102% 103%
M- 1385 Monomer Feed Line, MM18, Impinger #5 2 91% 89% 100% 102%
M- 1386 Monomer Feed Line, MM18, Impinger #6 2 92% 89% 100% 101%
M- 1387 Monomer Feed Line, MM18, Impinger #1 3 92% 88% 100% 102%
M- 1388 Monomer Feed Line, MM18, Impinger #2 3 92% 89% 101% 101%
M- 1389 Monomer Feed Line, MM18, Impinger #3 3 91% 89% 101% 100%
M- 1390 Monomer Feed Line, MM18, Impinger #4 3 91% 89% 100% 101%
HFPO Dilution; Re-analysis 91% 89% 101% 100%
M- 1391 Monomer Feed Line, MM18, Impinger #5 3 93% 90% 100% 101%
M- 1392 Monomer Feed Line, MM18, Impinger #6 3 90% 88% 100% 102%

No. Surrogate Target
1 4-Bromofluorobenzene 57% - 152%
2 1,2-Dichloroethane-d4 70% - 160%
3 Dibromofluoromethane 62% - 134%
4 Toluene-d8 71% - 139%

Chemours TO DE Test Report 30-Mar-21 42 Focus Project No. P-001446

Table 5-2. Monomer Waste Gas Method 8321A Analysis Surrogate Recoveries
EPA Method 537 Analysis Surrogate Recoveries Run
13C3 HFPO-DA
Sample Fraction No. 25-150%
M- 1375 Monomer Feed Line, MM18, Impinger #1 1 74%
M- 1376 Monomer Feed Line, MM18, Impinger #2 1 85%
M- 1377 Monomer Feed Line, MM18, Impinger #3 1 74%
M- 1378 Monomer Feed Line, MM18, Impinger #4 1 68%
M- 1379 Monomer Feed Line, MM18, Impinger #5 1 84%
M- 1380 Monomer Feed Line, MM18, Impinger #6 1 96%
M- 1381 Monomer Feed Line, MM18, Impinger #1 2 86%
M- 1382 Monomer Feed Line, MM18, Impinger #2 2 72%
M- 1383 Monomer Feed Line, MM18, Impinger #3 2 66%
M- 1384 Monomer Feed Line, MM18, Impinger #4 2 59%
M- 1385 Monomer Feed Line, MM18, Impinger #5 2 70%
M- 1386 Monomer Feed Line, MM18, Impinger #6 2 81%
M- 1387 Monomer Feed Line, MM18, Impinger #1 3 76%
M- 1388 Monomer Feed Line, MM18, Impinger #2 3 80%
M- 1389 Monomer Feed Line, MM18, Impinger #3 3 64%
M- 1390 Monomer Feed Line, MM18, Impinger #4 3 55%
M- 1391 Monomer Feed Line, MM18, Impinger #5 3 60%
M- 1392 Monomer Feed Line, MM18, Impinger #6 3 72%

Chemours TO DE Test Report 30-Mar-21 43 Focus Project No. P-001446
Table 5-3. Polymer Waste Gas Method 8260B Analysis Surrogate Recoveries
Method 8260B Analysis Surrogate Recoveries Run Surrogate Recovery
Sample Fraction No. 1 2 3 4
G- 1777 Polymer Feed Line, MM18, Impinger #1 1 94% 91% 100% 101%
G- 1778 Polymer Feed Line, MM18, Impinger #2 1 93% 92% 100% 101%
G- 1779 Polymer Feed Line, MM18, Impinger #3 1 92% 90% 99% 102%
G- 1780 Polymer Feed Line, MM18, Impinger #4 1 93% 88% 98% 103%
G- 1781 Polymer Feed Line, MM18, Impinger #5 1 90% 89% 98% 101%
G- 1782 Polymer Feed Line, MM18, Impinger #6 1 89% 89% 100% 103%
G- 1783 Polymer Feed Line, MM18, Impinger #1 2 91% 88% 99% 102%
G- 1784 Polymer Feed Line, MM18, Impinger #2 2 92% 89% 101% 103%
G- 1785 Polymer Feed Line, MM18, Impinger #3 2 91% 89% 99% 102%
G- 1786 Polymer Feed Line, MM18, Impinger #4 2 89% 89% 100% 102%
G- 1787 Polymer Feed Line, MM18, Impinger #5 2 91% 90% 101% 103%
G- 1788 Polymer Feed Line, MM18, Impinger #6 2 90% 88% 100% 102%
G- 1789 Polymer Feed Line, MM18, Impinger #1 3 90% 88% 100% 102%
G- 1790 Polymer Feed Line, MM18, Impinger #2 3 89% 89% 100% 102%
G- 1791 Polymer Feed Line, MM18, Impinger #3 3 90% 88% 100% 103%
G- 1792 Polymer Feed Line, MM18, Impinger #4 3 92% 88% 96% 102%
G- 1793 Polymer Feed Line, MM18, Impinger #5 3 91% 89% 100% 102%
G- 1794 Polymer Feed Line, MM18, Impinger #6 3 90% 88% 98% 102%

No. Surrogate Target
1 4-Bromofluorobenzene 57% - 152%
2 1,2-Dichloroethane-d4 70% - 160%
3 Dibromofluoromethane 62% - 134%
4 Toluene-d8 71% - 139%

Chemours TO DE Test Report 30-Mar-21 44 Focus Project No. P-001446
Table 5-4. Polymer Waste Gas Method 8321A Analysis Surrogate Recoveries
EPA Method 537 Analysis Surrogate Recoveries Run
13C3 HFPO-DA
Sample Fraction No. 25-150%
G- 1777 Polymer Feed Line, MM18, Impinger #1 1 118%
G- 1778 Polymer Feed Line, MM18, Impinger #2 1 109%
G- 1779 Polymer Feed Line, MM18, Impinger #3 1 102%
G- 1780 Polymer Feed Line, MM18, Impinger #4 1 100%
G- 1781 Polymer Feed Line, MM18, Impinger #5 1 104%
G- 1782 Polymer Feed Line, MM18, Impinger #6 1 106%
G- 1783 Polymer Feed Line, MM18, Impinger #1 2 102%
G- 1784 Polymer Feed Line, MM18, Impinger #2 2 107%
G- 1785 Polymer Feed Line, MM18, Impinger #3 2 101%
G- 1786 Polymer Feed Line, MM18, Impinger #4 2 107%
G- 1787 Polymer Feed Line, MM18, Impinger #5 2 102%
G- 1788 Polymer Feed Line, MM18, Impinger #6 2 105%
G- 1789 Polymer Feed Line, MM18, Impinger #1 3 109%
G- 1790 Polymer Feed Line, MM18, Impinger #2 3 106%
G- 1791 Polymer Feed Line, MM18, Impinger #3 3 107%
G- 1792 Polymer Feed Line, MM18, Impinger #4 3 107%
G- 1793 Polymer Feed Line, MM18, Impinger #5 3 103%
G- 1794 Polymer Feed Line, MM18, Impinger #6 3 106%

Chemours TO DE Test Report 30-Mar-21 45 Focus Project No. P-001446
Table 5-5. Stack Gas Modified Method 18 Analysis Surrogate Recoveries
Method 8260B Analysis Surrogate Recoveries Run
Surrogate
Recovery
Sample Fraction No. 1 2
QF- 1728 Stack Gas, MM18, Impinger #1 1 89% 103%
QF- 1729 Stack Gas, MM18, Impinger #2 1 91% 105%
QF- 1730 Stack Gas, MM18, Impinger #3 1 89% 106%
QF- 1731 Stack Gas, MM18, Impinger #4 1 89% 107%
QF- 1732 Stack Gas, MM18, Impinger #5 1 86% 104%
QF- 1733 Stack Gas, MM18, Impinger #6 1 88% 105%
QF- 1734 Stack Gas, MM18, Impinger #7 1 90% 107%
QF- 1735 Stack Gas, MM18, Impinger #1 2 88% 106%
QF- 1736 Stack Gas, MM18, Impinger #2 2 90% 106%
QF- 1737 Stack Gas, MM18, Impinger #3 2 94% 106%
QF- 1738 Stack Gas, MM18, Impinger #4 2 90% 106%
QF- 1739 Stack Gas, MM18, Impinger #5 2 90% 105%
QF- 1740 Stack Gas, MM18, Impinger #6 2 91% 106%
QF- 1741 Stack Gas, MM18, Impinger #7 2 88% 105%
QF- 1742 Stack Gas, MM18, Impinger #1 3 90% 108%
QF- 1743 Stack Gas, MM18, Impinger #2 3 90% 106%
QF- 1744 Stack Gas, MM18, Impinger #3 3 91% 107%
QF- 1745 Stack Gas, MM18, Impinger #4 3 90% 106%
QF- 1746 Stack Gas, MM18, Impinger #5 3 88% 106%
QF- 1747 Stack Gas, MM18, Impinger #6 3 88% 103%
QF- 1748 Stack Gas, MM18, Impinger #7 3 90% 105%

No. Surrogate Target
1 1,2-Dichloroethane-d4 50% - 150%
2 Dibromofluoromethane 50% - 150%

Chemours TO DE Test Report 30-Mar-21 46 Focus Project No. P-001446
Table 5-6. Stack Gas Modified Method 0010 Analysis Surrogate Recoveries
EPA Method 537 Analysis Surrogate Recoveries Run
Surrogate
Recovery
Sample Fraction No. 1 2 3
T- 1475 Stack Gas, MM0010, Front Half 1 104% NA NA
T- 1476 Composite
T- 1477 Stack Gas, MM0010, Back Half 1 98% 100% 89%
T- 1478 Composite
T- 1480
T- 1479 Stack Gas, MM0010, Impingers 1 101% 0% 0%
T- 1481 Stack Gas, MM0010, Breakthrough XAD 1 91% 0% 0%
T- 1482 Stack Gas, MM0010, Front Half 2 77% NA NA
T- 1483 Composite
T- 1484 Stack Gas, MM0010, Back Half 2 101% 104% 88%
T- 1485 Composite
T- 1487
T- 1486 Stack Gas, MM0010, Impingers 2 96% 0% 0%
T- 1488 Stack Gas, MM0010, Breakthrough XAD 2 77% 0% 0%
T- 1489 Stack Gas, MM0010, Front Half 3 79% NA NA
T- 1490 Composite
T- 1491 Stack Gas, MM0010, Back Half 3 59% 31% 20%
T- 1492 Composite
T- 1494
T- 1493 Stack Gas, MM0010, Impingers 3 103% 0% 0%
T- 1495 Stack Gas, MM0010, Breakthrough XAD 3 90% 0% 0%

No. Surrogate Target
1 13C3 HFPO-DA 25% - 150%
2 13C8 PFOA 50% - 150%
3 13C8 PFOS 50% - 150%

Chemours TO DE Test Report 30-Mar-21 47 Focus Project No. P-001446

Table 5-7. Thermal Oxidizer Modified Method 0010 Analysis Results
Parameter Units Run 1 Run 2 Run 3 BT PB
Method 0010 Front Half ug 0.0739 0.280 0.180 0.123
Method 0010 Back Half ug 0.0246 0.429 0.249 0.3510
Method 0010 Impingers ug 0.0583 0.0888 0.0972 0.0340
Total ug 0.157 0.798 0.526 0.508 0.00257
Method 0010 Breakthrough XAD ug 0.00920 0.0164 0.00717 0.00976

Methanol Reagent Blank HFPO-DA ug< 0.00160 ND
Deionized Water Blank HFPO-DA ug0.00194
XAD-2 Resin Media Check 1 HFPO-DA ug < 0.00160 ND
XAD-2 Resin Media Check 2 HFPO-DA ug < 0.00100 ND

Chemours TO DE Test Report 30-Mar-21 48 Focus Project No. P-001446

Table 5-8. Thermal Oxidizer Process Water Analyses

Demineralized Water Analyses
Compound Units Run 1 Run 2 Run 3 Average
Compounds by EPA 537
HFPO-DA ng/L 2.68 1.07 J 1.99 J 1.91
Compounds by Method 8260B
Carbonyl Difluoride mg/kg < 4.04 ND < 4.10 ND < 4.10 ND < 4.08 ND
HFPO-DAF mg/kg < 1.28 ND < 1.29 ND < 1.29 ND < 1.29 ND
HFPO mg/kg < 1.16 ND < 1.17 ND < 1.17 ND < 1.17 ND
Fluoroether(E-1) mg/kg < 1.33 ND < 1.34 ND < 1.34 ND < 1.34 ND

HF Acid Analyses
Compound Units Run 1 Run 2 Run 3 Average
Compounds by EPA 537
HFPO-DA ng/L 143 JH 98.6 J 153 J 132
Compounds by Method 8260B
Carbonyl Difluoride mg/kg < 3.98 ND < 3.96 ND < 4.0 ND < 3.98 ND
HFPO-DAF mg/kg < 1.25 ND < 1.25 ND < 1.26 ND < 1.25 ND
HFPO mg/kg < 1.14 ND < 1.14 ND < 1.14 ND < 1.14 ND
Fluoroether(E-1) mg/kg < 1.30 ND < 1.30 ND < 1.31 ND < 1.30 ND

Stage 4 Purge Analyses
Compound Units Run 1 Run 2 Run 3 Average
Compounds by EPA 537
HFPO-DA ng/L < 250 ND < 250 ND 46.0 J 182
Compounds by Method 8260B
Carbonyl Difluoride mg/kg < 3.94 ND < 3.92 ND < 3.94 ND < 3.93 ND
HFPO-DAF mg/kg < 1.24 ND < 1.24 ND < 1.24 ND < 1.24 ND
HFPO mg/kg < 1.13 ND < 1.12 ND < 1.13 ND < 1.13 ND
Fluoroether(E-1) mg/kg < 1.29 ND < 1.28 ND < 1.29 ND < 1.29 ND

Chemours TO DE Test Report 30-Mar-21 49 Focus Project No. P-001446 Run No.Impinger #1 (µg/Sample)Percent (%) Impinger #1Impinger #2 (µg/Sample)Percent (%) Impinger #2Impinger #3(µg/Sample)Percent (%) Impinger #3Impinger #4(µg/Sample)Percent (%) Impinger #4Impinger #5 (µg/Sample)Percent (%) Impinger #5Impinger #6(µg/Sample)Percent (%) Impinger #6Train Total (µg)1 47,900,000 94.9% 2,480,000 4.91% 103,000 0% 5,910 0% 0 0% 0 0% 50,488,9102 49,000,000 97.6% 1,060,000 2.11% 124,000 0% 6,640 0% 0 0% 0 0% 50,190,6403 52,900,000 94.1% 3,100,000 5.52% 176,000 0% 12,500 0% 0 0% 0 0% 56,188,500 47,900,0002,480,000103,0005,9100049,000,0001,060,000124,0006,6400052,900,0003,100,000176,00012,50000010,000,00020,000,00030,000,00040,000,00050,000,00060,000,000Impinger #1 (µg/Sample)Impinger #2 (µg/Sample)Impinger #3 (µg/Sample)Impinger #4 (µg/Sample)Impinger #5 (µg/Sample)Impinger #6 (µg/Sample)ug/SampleSampling Train Impinger NumberDistribution of Carbonyl Difluoride in Method 18 Train ComponentsRun #1Run #2Run #3 Figure 5-1. Monomer Waste Gas (Line #1) Modified Method 18 COF2 Capture
Chemours TO DE Test Report 30-Mar-21 50 Focus Project No. P-001446 Run No.Impinger #1 (µg/Sample)Percent (%) Impinger #1Impinger #2 (µg/Sample)Percent (%) Impinger #2Impinger #3(µg/Sample)Percent (%) Impinger #3Impinger #4(µg/Sample)Percent (%) Impinger #4Impinger #5 (µg/Sample)Percent (%) Impinger #5Impinger #6(µg/Sample)Percent (%) Impinger #6Train Total (µg)1 207,000 13.4% 334,000 21.6% 340,000 22.0% 266,000 17.2% 222,000 14.4% 174,000 11.3% 1,543,0002 84,000 9.21% 126,000 13.8% 232,000 25.4% 197,000 21.6% 162,000 17.8% 111,000 12.2% 912,0003 277,000 15.66% 401,000 22.7% 292,000 16.5% 366,000 20.7% 263,000 14.9% 170,000 9.6% 1,769,000 207,000334,000340,000266,000222,000174,00084,000126,000232,000197,000162,000111,000277,000401,000292,000366,000263,000170,000050,000100,000150,000200,000250,000300,000350,000400,000450,000Impinger #1 (µg/Sample)Impinger #2 (µg/Sample)Impinger #3 (µg/Sample)Impinger #4 (µg/Sample)Impinger #5 (µg/Sample)Impinger #6 (µg/Sample)ug/SampleSampling Train Impinger NumberDistribution of 2-MTP as HFPO in Method 18 Train ComponentsRun #1Run #2Run #3 Figure 5-2. Monomer Waste Gas (Line #1) Modified Method 18 HFPO Capture
Chemours TO DE Test Report 30-Mar-21 51 Focus Project No. P-001446 Run No.Impinger #1 (µg/Sample)Percent (%) Impinger #1Impinger #2 (µg/Sample)Percent (%) Impinger #2Impinger #3(µg/Sample)Percent (%) Impinger #3Impinger #4(µg/Sample)Percent (%) Impinger #4Impinger #5 (µg/Sample)Percent (%) Impinger #5Impinger #6(µg/Sample)Percent (%) Impinger #6Train Total (µg)1 1,730,000 84.4% 292,000 14.2% 18,300 0.893% 6,040 0.295% 2520 0.123% 1320 0.0644% 2,050,1802 2,560,000 92.5% 131,000 4.73% 50,900 1.84% 18,100 0.654% 5960 0.215% 2430 0.0878% 2,768,3903 2,360,000 83.5% 407,000 14.4% 36,900 1.31% 13,100 0.464% 6330 0.224% 2760 0.0977% 2,826,090 1,730,000292,00018,3006,040252013202,560,000131,00050,90018,100596024302,360,000407,00036,90013,100633027600500,0001,000,0001,500,0002,000,0002,500,0003,000,000Impinger #1 (µg/Sample)Impinger #2 (µg/Sample)Impinger #3 (µg/Sample)Impinger #4 (µg/Sample)Impinger #5 (µg/Sample)Impinger #6 (µg/Sample)ug/SampleSampling Train Impinger NumberDistribution of HFPO-DA in Method 18 Train ComponentsRun #1Run #2Run #3 Figure 5-3. Monomer Waste Gas (Line #1) Modified Method 18 HFPO-DA Capture
Chemours TO DE Test Report 30-Mar-21 52 Focus Project No. P-001446 Run No.Impinger #1 (µg/Sample)Percent (%) Impinger #1Impinger #2 (µg/Sample)Percent (%) Impinger #2Impinger #3(µg/Sample)Percent (%) Impinger #3Impinger #4(µg/Sample)Percent (%) Impinger #4Impinger #5 (µg/Sample)Percent (%) Impinger #5Impinger #6(µg/Sample)Percent (%) Impinger #6Train Total (µg)1 74.9 0% 22.8 0% 13.2 0% 0 0% 0 0% 0 0% 1112 83.6 0% 41.5 0% 0 0% 0 0% 0 0% 0 0% 1253 120 0% 74.2 0% 40.3 0% 13.2 0% 0 0% 0 0% 248 74.922.813.200083.641.5000012074.240.313.2000.020.040.060.080.0100.0120.0140.0Impinger #1 (µg/Sample)Impinger #2 (µg/Sample)Impinger #3 (µg/Sample)Impinger #4 (µg/Sample)Impinger #5 (µg/Sample)Impinger #6 (µg/Sample)ug/SampleSampling Train Impinger NumberDistribution of HFPO dimer, methyl ester as HFPO-DAF in Method 18 Train ComponentsRun #1Run #2Run #3 Figure 5-4. Polymer Waste Gas (Line #2) Modified Method 18 HFPO-DAF Capture
Chemours TO DE Test Report 30-Mar-21 53 Focus Project No. P-001446 Run No.Impinger #1 (µg/Sample)Percent (%) Impinger #1Impinger #2 (µg/Sample)Percent (%) Impinger #2Impinger #3(µg/Sample)Percent (%) Impinger #3Impinger #4(µg/Sample)Percent (%) Impinger #4Impinger #5 (µg/Sample)Percent (%) Impinger #5Impinger #6(µg/Sample)Percent (%) Impinger #6Train Total (µg)1 600 100.0% 0 0.00% 0 0% 0 0% 0 0% 0 0% 6002 161 100.0% 0 0.00% 0 0% 0 0% 0 0% 0 0% 1613 1,140 96.0% 48.1 4.05% 0 0% 0 0% 0 0% 0 0% 1,188 60000000161000001,14048.1000002004006008001,0001,200Impinger #1 (µg/Sample)Impinger #2 (µg/Sample)Impinger #3 (µg/Sample)Impinger #4 (µg/Sample)Impinger #5 (µg/Sample)Impinger #6 (µg/Sample)ug/SampleSampling Train Impinger NumberDistribution of Carbonyl Difluoride in Method 18 Train ComponentsRun #1Run #2Run #3 Figure 5-5. Polymer Waste Gas (Line #2) Modified Method 18 COF2 Capture
Chemours TO DE Test Report 30-Mar-21 54 Focus Project No. P-001446 Run No.Impinger #1 (µg/Sample)Percent (%) Impinger #1Impinger #2 (µg/Sample)Percent (%) Impinger #2Impinger #3 (µg/Sample)Percent (%) Impinger #3Impinger #4 (µg/Sample)Percent (%) Impinger #4Impinger #5 (µg/Sample)Percent (%) Impinger #5Impinger #6 (µg/Sample)Percent (%) Impinger #6Train Total (µg)1468 0% 40.8 0% 5.56 0% 0 0% 0 0% 0 0%5142499 0% 38.8 0% 0 0% 0 0% 0 0% 0 0%53831,350 0% 127 0% 23.0 0% 0 0% 0 0% 0 0%1,500 46840.85.5600049938.800001,35012723.000002004006008001,0001,2001,4001,600Impinger #1 (µg/Sample)Impinger #2 (µg/Sample)Impinger #3 (µg/Sample)Impinger #4 (µg/Sample)Impinger #5 (µg/Sample)Impinger #6 (µg/Sample)ug/SampleSampling Train Impinger NumberDistribution of Heptafluoropropyl 1,2,2,2-tetrafluoroethyl ether in Method 18 Train ComponentsRun #1Run #2Run #3 Figure 5-6. Polymer Waste Gas (Line #2) Modified Method 18 Fluoroether E-1 Capture
Chemours TO DE Test Report 30-Mar-21 55 Focus Project No. P-001446 Run No.Impinger #1 (µg/Sample)Percent (%) Impinger #1Impinger #2 (µg/Sample)Percent (%) Impinger #2Impinger #3(µg/Sample)Percent (%) Impinger #3Impinger #4(µg/Sample)Percent (%) Impinger #4Impinger #5 (µg/Sample)Percent (%) Impinger #5Impinger #6(µg/Sample)Percent (%) Impinger #6Train Total (µg)1 50,200 62.3% 15,300 19.0% 10,600 13.2% 3,480 4.32% 827 1.03% 154 0.191% 80,5612 76,900 67.4% 32,900 28.8% 3,940 3.45% 273 0.239% 50.3 0.0441% 0 0% 114,0633 109,000 53.7% 57,900 28.6% 25,600 12.6% 8,540 4.21% 1560 0.769% 202 0.100% 202,802 50,20015,30010,6003,48082715476,90032,9003,94027350.30109,00057,90025,6008,5401560202020,00040,00060,00080,000100,000120,000Impinger #1 (µg/Sample)Impinger #2 (µg/Sample)Impinger #3 (µg/Sample)Impinger #4 (µg/Sample)Impinger #5 (µg/Sample)Impinger #6 (µg/Sample)ug/SampleSampling Train Impinger NumberDistribution of HFPO-DA in Method 18 Train ComponentsRun #1Run #2Run #3 Figure 5-7. Polymer Waste Gas (Line #2) Modified Method 18 HFPO-DA Capture

Chemours TO DE Test Report 30-Mar-21 56 Focus Project No. P-001446

6.0 CONCLUSION
The Chemours thermal oxidizer is controlling PFAS emissions at an average efficiency exceeding
99.99951%, demonstrating compliance with the consent order requirement to control all PFAS at an
efficiency of 99.99%.