NC0003573_Application_20210921

11 Chemours.
June 13, 2021
Sergei Chernikov
NCDEQ Division of Water Resources
NPDES Unit
1617 Mail Service Center
Raleigh, North Carolina 27699-1679
[e-mail]
The Chemours Company
Fayetteville Works
22828 NC Highway 87 W
Fayetteville, NC 28306
Re: Chemours Fayetteville Works NPDES Permit Application for the
Groundwater Treatment System
Dear Mr. Chernikov:
The Chemours Company — Fayetteville Works is submitting a National Pollutant Discharge
Elimination System (NPDES) permit application to North Carolina Department of
Environmental Quality (NCDEQ) for the above -referenced facility. This facility is required
under the Addendum to Consent Order Paragraph 12 to reduce mass loading of per- and
polyfluoroalkyl substances (PEAS) from seeps and groundwater to the Cape Fear River. The
Addendum to the Consent Order requires that Chemours commence full operation of the
proposed groundwater remedy no later than March 15, 2023. The Groundwater Treatment
System needs to be operational no later than April 1, 2022 to meet the Consent Order
obligations.
Your timely review of this application is therefore much appreciated. Chemours would like
to schedule a meeting in early July to review and discuss this application with you. In the
meantime, if you have any questions or need additional information, please contact Christel
Compton at [phone].
Sincerely,
111.
Dawn M. Hughes
Plant Manager
Chemours — Fayetteville Works

Chemours Fayetteville Works
NPDES Permit Application Update
Groundwater Treatment System
June 2021

CChemours
Chemours Fayetteville Works
NPDES Permit Application Update
GROUNDWATER TREATMENT SYSTEM
Legend
• Extraction well
PIanued groundwater remedy route
June 2021

NPDES PERMIT APPLICATION —JUNE 13, 202
Chemours Fayetteville Works NPDES Permit Application for the Groundwater
Treatment System
Table of Contents
Application Introduction
• General Discussion regarding NPDES Application
Attachment A — Groundwater Treatment System (GWTS) — Outfall 004
• Attachment A.1 GWTS — Form 2D
• Attachment A.2 Line Drawing
• Attachment A.3 Justification for Presence of Pollutants
• Attachment A.4 Chemours Fayetteville Works — Groundwater and Seeps Water Quality
Assessment
• Attachment A.5 Engineering Report — Treatment of Groundwater and Upgradient Seeps
Water
• Attachment A.6 Engineering Alternatives Analysis — Treatment of Groundwater and
Upgradient Seeps Water
2

NPDES PERMIT APPLICATION —JUNE 13, 2021
Chemours Fayetteville June 13, 2021 NPDES Permit Application for the Groundwater
Treatment System
The Chemours Company FC, LLC (Chemours) is providing this National Pollutant Discharge
Elimination System (NPDES) permit application for discharges from a Groundwater Treatment
System (GWTS) at Fayetteville Works. The GWTS is required under the Addendum to Consent
Order (CO) between Chemours and the North Carolina Department of Environmental Quality
(NCDEQ). The objective of the GWTS is to reduce mass loading of per- and polyfluoroalkyl
substances (PFAS) from seeps and groundwater to the Cape Fear River, as measured by three
indicator PFAS.1 The GWTS will discharge into the pipe that conveys effluent from Outfall 002
from Chemours Fayetteville Works Site (the Site) to the Cape Fear River.
This will be the third NPDES permit associated with the Site. The first permit authorizes discharges
to the Cape Fear River through Outfall 002 under NC003573. Chemours is also authorized under
NC0089915 to discharge effluent from Outfall 003 to the Cape Fear River. The design of the
GWTS is similar to the design of the treatment system for Outfall 003. The effluent data that has
been submitted to NCDEQ with EPA Form 2C for permit number NC0089915 is therefore
considered to be suitable to estimate the expected effluent data for the GWTS.
The application for this new discharge consists of Form 2D and its various attachments.
1 The three indicator PFAS are hexafluoropropylene oxide-dimer acid (HFPO-DA), perfluoro-2-methoxypropanoic
acid (PMPA), and perfluoro-l-methoxyacetic acid (PFMOAA).
3

Attachment A.1 — Form 2D Outfall 004

EPA Identification Number
NCD 047 368 642
NPDES Permit Number
Facility Name
Chemours Co -Fayetteville Works
Form Approved 03/05/19
OMB No. 2040-0004
Form
2D
NPDES
EPA
U.S. Environmental Protection Agency
Application for NPDES Permit to Discharge Wastewater
NEW MANUFACTURING, COMMERCIAL, MINING, AND SILVICULTURAL OPERATIONS
THAT HAVE NOT YET COMMENCED DISCHARGE OF PROCESS WASTEWATER
SECTION 1. EXPECTED OUTFALL LOCATION (40 CFR 122.21(k)(1))
Outfall Location
1.1 Provide information on each of the facility's outfalls in the table below.
Outfall
Number
Receiving Water
Name
Latitude
Longitude
004
Cape Fear River
34° 50' 19.28" N
78° 49' 32.70" W
SECTION 2. EXPECTED DISCHARGE DATE (40 CFR 122.21(k)(2))
2.1
Month
Day
Year
April
01
2022
SECTION 3. AVERAGE FLOWS AND TREATMENT (40 CFR 122.21(k)(3)(i))
3.1
Average Flows and Treatment
For each outfall identified under Item 1.1, provide average flow and treatment information. Add additional sheets as
necessary.
**Outfall Number** 004
Operations Contributing to Flow
Operation
Groundwater extraction wells and seeps
Average Flow
1.756 mgd
mgd
mgd
mgd
mgd
Description
(include size, flow rate through each treatment unit,
retention time, etc.)
Code from
Exhibit 2D-1
Final Disposal of Solid or Liquid
Wastes Other Than by Discharge
Chemical precipitation, 1,000-1,500 gpm
2-C
N/A
Flocculation, 1,000-1,500 gpm
2-D
N/A
Sedimentation, 1,000-1,500 gpm
1-U
N/A
Ultrafiltration, 1,000-1,500 gpm
1-Q
N/A
Carbon adsorption, 1,000-1,500 gpm
2-A
N/A (See Page 2 for continuation)
EPA Form 3510-2D (Revised 3-19) Page 1

EPA Identification Number
NCD 047 368 642
NPDES Permit Number
Facility Name
Chemours Co -Fayetteville Works
Form Approved 03/05/19
OMB No. 2040-0004
Average Flows and Treatment Continued
3.1
Cont.
**Outfall Number**
004
Operations Contributing
to Flow
Operation
Average Flow
mgd
mgd
mgd
mgd
Treatment
Description
(include size, flow rate through each treatment unit,
retention time, etc.)
Units
Code from
Exhibit 2D-1
mgd
Final Disposal of Solid or Liquid
Wastes Other Than by Discharge
Discharge to surface water
4-A
N/A
Gravity thickening (sludge from sedimentation)
5-L
N/A
Belt filtration or centrifugation (sludge)
5-C or 5-D
Certified landfill
**Outfall Number**
Operations Contributing
to Flow
Operation
Average Flow
mgd
mgd
mgd
mgd
mgd
Treatment Units
Description
(include size, flow rate through each treatment unit,
retention time, etc.)
Code from
Exhibit 2D-1
Final Disposal of Solid or Liquid
Wastes Other Than by Discharge
EPA Form 3510-2D (Revised 3-19)
Page 2

EPA Identification Number
NCD 047 368 642
NPDES Permit Number
Facility Name
Chemours Co -Fayetteville Works
Form Approved 03/05/19
OMB No. 2040-0004
SECTION
4. LINE DRAWING (40 CFR
122.21(k)(3)(ii))
3
J o
4.1
Have you
balance?
attached a line drawing to this
(See instructions for drawing requirements.
Yes
application
that shows the water flow through your facility with a water
See Exhibit 2D-2 at end of instructions for example.)
No
11g1
■
SECTION
5. INTERMITTENT
OR SEASONAL FLOWS (40 CFR 122.21(k)(3)(iii))
cn
Production o Intermittent or Seasonal Flows
0
5.1
Except for
or seasonal?
stormwater runoff, leaks, or spills,
Yes
are
any expected discharges described in Sections 1 and 3 intermittent
No 4 SKIP to Section 6.
■
0
5.2
Provide information on intermittent or seasonal flows for each applicable outfall. Attach additional pages, if
necessa .
Outfall
Number
Operations
(list)
Frequency
Rate and Volume
Duration
Average
Days/Week
Average
Months/Year
Maximum Daily
Discharge
Maximum Total
Volume
days/week
months/year
mgd
gallons
days
days/week
months/year
mgd
gallons
days
days/week
months/year
mgd
gallons
days
Outfall
Number
Operations
(list)
Frequency
Rate and Volume
Duration
Average
Days/Week
Average
Months/Year
Maximum Daily
Discharge
Maximum Total
Volume
days/week
months/year
mgd
gallons
days
days/week
months/year
mgd
gallons
days
days/week
months/year
mgd
gallons
days
Outfall
Number
Operations
(list)
Frequency
Rate and Volume
Duration
Average
Days/Week
Average
Months/Year
Maximum Daily
Discharge
Maximum Total
Volume
days/week
months/year
mgd
gallons
days
days/week
months/year
mgd
gallons
days
days/week
months/year
mgd
gallons
days
N 6. PRODUCTION
(40 CFR 122.21(k)(4))
6.1
Do any effluent limitation guidelines
❑ Yes
(ELGs)
promulgated
by EPA under CWA Section
No 4 SKIP to Section
304 apply to your facility?
7.
✓
6.2
Provide the following information on applicable ELGs.
ELG Category
ELG Subcategory
Regulatory Citation
EPA Form 3510-2D (Revised 3-19)
Page 3

EPA Identification Number
NCD 047 368 642
NPDES Permit Number
Facility Name
Chemours Co -Fayetteville Works
Form Approved 03/05/19
OMB No. 2040-0004
0)
Effluent Characteristics ci Production Continued
0
6.3
Are the limitations in the applicable ELGs expressed in terms of production (or other measure of operation)?
❑ Yes ❑ No 4 SKIP to Section 7.
6.4
Provide an expected measure of average daily production expressed in terms and units of applicable ELGs.
Expected Actual Average Daily Production for First Three Years
Outfall
Number
Year
Operation, Product, or Material
Quantity per Day
(note basis if applicable)
Unit of Measure
Year 1
Year 2
Year 3
Year 1
Year 2
Year 3
Year 1
Year 2
Year 3
7. EFFLUENT
CI-ARACTER1STICS
(40 CFR 122.21(k)(5))
See the instructions to determine the parameters and pollutants you are required to monitor and, in turn, the tables you must
complete. Note that not all applicants need to complete each table.
Table A. Conventional and Non -Conventional Parameters
7.1
Are you requesting
of your outfalls?
a waiver from your NPDES permitting
authority
for one or more of the Table A parameters for any
No 4 SKIP to Item 7.3.
• Yes
0
7.2
If yes, indicate the applicable outfalls below. Attach waiver request and other required information to the application.
Outfall number Outfall number Outfall number
7.3
Have you
waiver has
have provided estimates or actual data
not been requested and attached the
for all Table A
results to this
parameters for each of your outfalls for which a
application package?
No; a waiver has been requested from my
NPDES permitting authority for all parameters at
all outfalls.
0 Yes
•
Table B. Certain Conventional and Non -Conventional Pollutants
7.4
Have you
applicable
checked "Believed Present" for all pollutants listed in Table B that are limited directly or indirectly by an
ELG?
Yes ❑ No
✓
7.5
Have you
checked `Believed Present" or "Believed Absent" for all remaining pollutants listed in Table B?
Yes ❑ No
✓
7.6
Have you
in your discharge?
provided estimated data for those Table B pollutants for which you have indicated are "Believed Present"
Yes ❑ No
✓
EPA Form 3510-2D (Revised 3-19)
Page 4

EPA Identification Number
NCD 047 368 642
NPDES Permit Number
Facility Name
Chemours Co -Fayetteville Works
Form Approved 03/05/19
OMB No. 2040-0004
Engineering Report Effluent Characteristics Continued
0
Table C. Toxic Metals, Total Cyanide, and Total Phenols
7.7
Have you indicated
for all outfalls?
whether pollutants are "Believed Present" or "Believed Absent" for all pollutants listed on Table C
❑ No
✓ Yes
7.8
Have you completed
including the source
Table C by providing estimated data for pollutants you indicated are `Believed Present,"
of the information, for each applicable outfall?
❑ No
✓ Yes
Table D. Organic Toxic Pollutants (GC/MS Fractions)
7.9
Do you qualify for
Yes 4
a small business exemption under
Note that you qualify at the top
Table D, then SKIP to Item 7.12.
the criteria specified in the Instructions?
of No
7.10
Have you indicated
for all outfalls?
whether pollutants are "Believed Present" or "Believed Absent" for all pollutants listed on Table D
❑ No
✓ Yes
7.11
Have you completed
including the source
Table D by providing estimated data for pollutants you indicated are "Believed Present,"
of the information, for each applicable outfall?
❑ No
1 Yes
2,3,7,8-Tetrachlorodibenzo-p-Dioxin (TCDD)
7.12
Does the facility use or manufacture one or more
know or have reason to believe that TCDD is or
❑ Yes
of the 2,3,7,8-TCDD congeners listed
may be present in effluent from any
in the Instructions, or do you
of your outfalls?
✓ No
Table E. Certain Hazardous Substances and Asbestos
7.13
Have you indicated whether pollutants are "Believed
for all outfalls?
❑ Yes
Present" or "Believed Absent"
for all pollutants listed in Table E
1 No
7.14
Have you completed Table E by reporting the reason
quantitative data for pollutants you indicated are
❑ Yes
the pollutants are expected to
"Believed Present" for each applicable
be present and available
outfall?
1 No
Intake Credits, Tables A through E
7.15
N 8. ENGINEERING
8.1
Are you applying for
outfalls?
❑ Yes 4
REPORT
Do you have any
studies?
net credits for the presence
Consult with your NPDES permitting
authority.
(40 CFR 122.21(k)(6))
technical evaluations of your wastewater
of any of the pollutants on Tables
A through E for any of your
reports or pilot plant
Item 8.3.
✓ No
treatment, including engineering
❑ No 4 SKIP to
1 Yes
8.2
Have you provided
the technical evaluation and all related documents to this application package?
❑ No
✓ Yes
8.3
Are you aware of
treatment at your
any existing plant(s) that resemble production processes, wastewater constituents, or wastewater
facility?
❑ No 4 SKIP to Section 9.
✓ Yes
EPA Form 3510-2D (Revised 3-19)
Page 5

EPA Identification Number
NCD 047 368 642
NPDES Permit Number
Facility Name
Chemours Co -Fayetteville Works
Form Approved 03/05/19
OMB No. 2040-0004
cn Engineering Report
Other Information 0 Continued
0
8.4
9. OTHER
9.1
Provide the name and location of the similar plants.
Name of Similar Plants
Location of Similar Plants
Treatment System for Outfall 003 (Old Outfall 002)
Fayetteville Works, Old Outfall 002 Channel
INFORMATION
Have you attached
(i.e., material beyond
(40 CFR 122.21(k)(7))
any optional information that you would
that which you have already noted
like considered as part of the application review process
in the application as being attached)?
❑ No 4 SKIP to Section 10.
✓ Yes
9.2
List the additional items and briefly note why you have included them.
1. Attachment A.4 Chemours Fayetteville Works — Groundwater and Seeps Water Quality Assessment
2. Attachment A.5 GWTS Engineering Report and Data Analysis
3. Attachment A.6 Engineering Alternatives Analysis — GWTS Discharge
4.
5.
Checklist and Certification Statement
10. CHECKLIST
10.1
AND CERTIFICATION STATEMENT (40 CFR 122.22(a) and (d))
In Column 1 below, mark the sections of Form 2D that you have completed and are submitting with your application.
For each section, specify in Column 2 any attachments that you are enclosing to alert the permitting authority. Note
that not all applicants are required to complete all sections or tables, or provide attachments.
Column 1
Column 2
Section
1: Expected Outfall
w/ attachments (e.g., responses for additional outfalls)
✓
•
Location
Section
2: Expected
Date
w/ attachments
✓
•
Discharge
Section
3: Average Flows
w/ attachments
✓
•
and Treatment
4: Line Drawing
w/ line
w/ additional attachments
✓ Section
0
drawing ■
❑ Section 5: Intermittent or
Seasonal Flows
w/ attachments
•
❑ Section 6: Production
w/ attachments
•
Section
7: Effluent
w/ Table
request
approval
Table
Table
w/ other
attachmentscompounds
A waiver
Table A
Table C
Table E
Report) identifies PFA,
and potentially in the outfal
•
or 0
0
B 0
✓
Characteristics
0
D ■
Attachment A.5 (Engineering
in the intake
Igl
Section
8: Engineering
w/ technical evaluations and related attachments
✓
MI
Report
❑ Section 9: Other Information
■
w/ optional information
Section
10: Checklist and
Statement
■
w/ attachments
✓
Certification
EPA Form 3510-2D (Revised 3-19)
Page 6

EPA Identification Number
NCD 047 368 642
NPDES Permit Number
Facility Name
Chemours Co -Fayetteville Works
Form Approved 03/05119
OMB No. 2040-0004
10.2
Certification Statement
I certify under penalty of law that this document and all attachments were prepared under my direction or supervision
in accordance with a system designed to assure that qualified personnel properly gather and evaluate the
information submitted. Based on my inquiry of the person or persons who manage the system, or those persons
directly responsible for gathering the information, the information submitted is, to the best of my knowledge and
belief, true, accurate, and complete. t am aware that there are significant penalties for submitting false information,
including the possibility of fine and imprisonment for knowing violations.
Name (print or type first and last name)
Dawn M. Hughes
Official title
Plant Manager
Signature
bu.— A
• 4--
Date signed
[a /rl/Zo Si
EPA Form 3510.2D (Revised 3-19) Page 7

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Form Approved 03/05/19
OMB No. 2040-0004
Intake Water
Believed Present?
(check only one response per
parameter)
Check here if you have applied to your NPDES authority for a waiver for all of the pollutants listed on this table for the noted outfall.
0
z
0
z
0
z
0
z
0
z
0
z
0
z
0
z
co
a a))
>-
co
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>-
a`�))
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a)
>-
a` )) )
>-
a)
>-
a` ))
>-
` ))
a
>-
>
>
>
>
>
>
>
>
ATES (40 CFR 122.21(k)(5)(i))'
Effluent Data
Maximum Daily Average Daily Source of Information
Discharge Discharge (use codes in instructions)
(required) (if available)
m
m
m
m
m
m
m
0utfall Number
004
LO
ui
O
A
<25,000
V
CD
O
0
O
0
1-I
22.3
23.0
rsi
c-I
CD
8.85
EPA Identification Number Facility Name
NCD 047 368 642 Chemours Co -Fayetteville Works
mg/L
mg/L
mg/L
mg/L
mg/L
MGD
°C
00
0)
u5
Concentration
Mass
Concentration
Concentration
N
Concentration
Mass
Concentration
Mass
a)
oC
°C
Standard units
Standard units
❑
❑
❑
❑
❑
❑
❑
❑
❑
❑
Z
Q
J
Q
Z
0
I—
W CO
z 2
O 0
0 a
d
W
J
m
H❑
Biochemical oxygen
demand (BOD5)
Chemical oxygen demand
(COD)
Total organic carbon
(TOC)
Total suspended solids
(TSS)
Ammonia (as N)
o
u_
Temperature (winter)
Temperature (summer)
pH (minimum)
E
E
'R
as
E
--
a
.—
N
M
4
cci
(O
ti
00
a)
0
E
ca
co
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0
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a)
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M_
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EPA Form 3510-2D (Revised 3-19)

This page intentionally left blank.

Outfall Number
O
0
Chemours Co -Fayetteville Works
EPA Identification Number
NCD 047 368 642
VENTIONAL POLLUTANTS (40 CFR 122.21(k)(5)(ii))l
Estimated Data for Pollutants Expected to be Present or Limited by an ELG
(Provide both concentration and mass estimates for each pollutant.)
Intake Water 1
Believed Present?
(check only one
response per item)
Check (✓) here if you believe all pollutants listed to be absent from the discharge. You need not complete Table B for the noted outfall unless you have quantitative data available.
❑ Yes ✓❑ No
❑✓ Yes ❑ No
❑✓ Yes ❑ No
❑✓ Yes ❑ No
O
Z
Cl)
o
>-
❑✓ Yes ❑ No
❑✓ Yes ❑ No
❑✓ Yes ❑No
❑✓ Yes No
❑✓ Yes ❑ No
❑✓ Yes ❑ No
I
Effluent
Source of Information
(use codes in instructions)
m
m
m
m
m
m
m
m
m
m
m
Average Daily
Discharge
(if available)
Maximum Daily
Discharge
re uired
0
M
V
0
m
N
O
0
O
V
0
O
V
0
N
O
vO
<0.04
0
^
d
0
ci
N
0
l0
rn
0
o
^
0
O^
O
v
N
m
J
no
E
mg/L
PCU
E
O
0
It
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
Concentration
Mass
Concentration
Mass
Concentration
Mass
Concentration
Mass
Concentration
Mass
Concentration
Mass
Concentration
co
Ca
G
Concentration
N
N
as
c
Concentration
Mass
Concentration
coco
co
Ca
c
Concentration
Mass
,117
le
WI
u
Presence or Absence
(check one)
Believed
Absent
lia■
■
■
■
■
■
■
■
■
■
El■
144
Believed
Present
Pig
467
hi
AP Y
7T 7
a
Tr
Bromide
(24959-67-9)
Chlorine, total
residual
U
Fecal coliform
Fluoride
(16984-48-8)
Nitrate -nitrite
Nitrogen, total
organic (as N)
Oil and grease
Phosphorus (as P),
total (7723-14-0)
Sulfate (as SO4)
(14808-79-8)
Sulfide (as S)
Effluent data are from EPA Form 2C for Outfall 003 (04/01/21).
EPA Form 3510-2D (Revised 3-19)

Outfall Number
O
O
Chemours Co -Fayetteville Works
EPA Identification Number
NCD 047 368 642
Intake Water 1
Believed Present?
(check only one
response per item)
❑ Yes ❑✓ No
❑ Yes ✓❑ No
❑✓ Yes ❑ No
❑✓ Yes ❑ No
❑✓ Yes ❑ No
❑✓ Yes ❑ No
❑ Yes ✓❑ No
❑✓ Yes ❑ No
VENTIONAL POLLUTANTS (40 CFR 122.21(k)(5)(ii))l
Estimated Data for Pollutants Expected to be Present or Limited by an ELG
(Provide both concentration and mass estimates for each pollutant.)
0
z
(/)
>-
0
z
N
>-
❑ Yes ✓❑ No
Effluent
Source of Information
(use codes in instructions)
M
M
M
M
m
m
M
M
M
M
M
Average Daily
Discharge
(if available)
Maximum Daily
Discharge
re uired
0
N
v
0
O
V
0
lD
0
O
u1
<12.0
0
m
ti
0
M
V
0
O
0
ri
0
M
.--I
p
v
0
m
0
0
0)
p
v
N
mg/L
J
bb
3
0
J
bb
3
0
J
00
Z
0
J
bb
3
ug/L 0
ug/L p
0
J
00
Z
0
J
00
7
0
J
bb
3
J
/0
3
Concentration
Mass
Concentration
Mass
Concentration
Mass
Concentration
Mass
Concentration
Mass
Concentration
Mass
Concentration
Mass
Concentration
Mass
Concentration
Mass
Concentration
N
as
c�
G
Concentration
Mass
•
T
Ei
E.
6J
Tf
Presence or Absence
(check one)
Believed
Absent
El
0
■
■
■
■
■
■
0
■
0
Believed
Present
.
.
El
■
El
■
►
•
in
Y
ITirl 7
0
0-
M"
PriN
Sulfite (as SO3)
(14265-45-3)
Surfactants
Aluminum, total
(7429-90-5)
Barium, total
(7440-39-3)
Boron, total
(7440-42-8)
Cobalt, total
(7440-48-4)
Iron, total
(7439-89-6)
Magnesium, total
(7439-95-4)
Molybdenum, total
(7439-98-7)
Manganese, total
(7439-96-5)
Tin, total
(7440-31-5)
N
N
Effluent data are from EPA Form 2C for Outfall 003 (04/01/21).
EPA Form 3510-2D (Revised 3-19)

Outfall Number
0
O
O
Chemours Co -Fayetteville Works
EPA Identification Number
NCD 047 368 642
VENTIONAL POLLUTANTS (40 CFR 122.21(k)(5)(ii))l
Estimated Data for Pollutants Expected to be Present or Limited by an ELG
(Provide both concentration and mass estimates for each pollutant.)
Intake Water 1
Believed Present?
(check only one
response per item)
❑✓ Yes ❑ No
❑✓ Yes ❑ No
❑✓ Yes ❑ No
0
z
y
>-
❑✓ Yes ❑ No
Effluent
Source of Information
(use codes in instructions)
M
m
m
m
m
Average Daily
Discharge
(if available)
Maximum Daily
Discharge
re uired
0
o
V
0
a
v
2.42
<0.208
CV
Ci
N
J
pCi/L
pCi/L
J
U
a
J
U
a
Concentration
Mass
Concentration
Mass
Concentration
Mass
Concentration
Mass
Concentration
Mass
•
Presence or Absence
(check one)
Believed
Absent
M'Tal
i
u
Tf
Believed
Present
i
4-4
i 1,4
il
COAP
3
a
IT
r
inn
'i
Titanium, total
(7440-32-6)
.5
CO
Et
Alpha, total
o
m
Radium, total
Radium 226, total
N
N
N
N
N
C7
N
N
O
co
a)
U)
E
ca
0_
0
C6
0
O_
O
C/)
as
0
C6
0
O_
O
U
T
=
C
N
a)
0
0
(0
M
U
`a)
0
0,
a)
0
0
a
0
a) Cam')
o a)
L
O N
E (<1
N
a)
Cn
a) U
o
-0v
U
c
• CO
co_ co
0
0
N
(1) 0
._
a) a)
u) a)
>,
aai▪ 0
U_ O
� Z
a)
▪ Q
rn Co
O U
O 0)
U Cn
U
Ca
- a)
(1) Q
(.)CO
7 L
0, U
0 LL
0 L.L
a) °
o
— v
0 a)
� C
0
-• 8
E
N
Cn
a)
Effluent data are from EPA Form 2C for Outfall 003 (04/01/21).
EPA Form 3510-2D (Revised 3-19)

This page intentionally left blank.

Form Approved 03/05/19
OMB No. 2040-0004
scharge
Intake Water
Believed Present?
(Check only one
response per pollutant.)
Check (✓) here if you believe all pollutants listed to be absent from the discharge. You need not complete Table C for the noted outfall unless you have quantitative data
available.
0
z
0
z
❑
0
z
❑"3.❑
0
z
0
z
0
z
❑
0
z
❑
0
z
❑
0
z
❑
0
z
❑
0
z
>
0
z
>
0
z
❑
0
z
❑
0
z
❑ Yes
co
a)
>
co
a)
>
ti
a)
❑
a)
'
co
a)
>
✓❑ Yes
✓❑ Yes
0
a>
'
0
a)
>
❑ Yes
co
a)
❑
cn
a)
>
cn
a)
>
v)
a)
❑
Number Facility Name Outfall Number
642 Chemours Co -Fayetteville Works 004
, TOTAL CYANIDE, AND TOTAL PHENOLS (40 CFR 122.21(k)(5)(iii)(A))1
Presence or Absence Estimated Data for Pollutants Expected to be Present in Di
(check one) (Provide both concentration and mass estimates for each pollutant.)
m
m
m
m
m
m
m
m
m
m
m
m
m
m
m
Cr
v
co
ov
<0.12
<10
m
ov
<10
o
v
m
ri
m
<10
<0.48
<10
rs1
xi
v
<5
<10
ug/L
ug/L
ug/L
ug/L
ug/L
ug/L
ug/L
ng/L
ug/L
ug/L
ug/L
ug/L
ug/L
ug/L
ug/L
Concentration
Mass
Concentration
Mass
Concentration
Mass
Concentration
Mass
Concentration
Mass
Concentration
Mass
Concentration
Mass
Concentration
Mass
Concentration
Mass
Concentration
N
ca
Concentration
Mass
Concentration
Mass
Concentration
Mass
Concentration
Mass
Concentration
N
ca
0
■
■
0
■
■
■
❑
■
■
0
■
❑
■
0
0
0
0
0
0
0
0
M
0
0
0
Antimony, Total
(7440-36-0)
Arsenic, Total
(7440-38-2)
Beryllium, Total
(7440-41-7)
Cadmium, Total
(7440-43-9)
Chromium, Total
(7440-47-3)
Copper, Total
(7440-50-8)
Lead, Total
(7439-92-1)
Mercury, Total
(7439-97-6)
Nickel, Total
(7440-02-0)
Selenium, Total
(7782-49-2)
0 c.,
N
)
4 O
> d'
N
Thallium, Total
(7440-28-0)
Zinc, Total
(7440-66-6)
Cyanide, Total
(57-12-5)
Phenols, Total
❑
(Ni
M
Lf)
(O
f�
00
O)
.—
.—
M
V
Lri
•,-
0
m
E
ca
co
0
c
ca
0
0
cn
c
ca
0
0
0
co
T
ca
(a
0
L
co
c
LL
U
O
0
0
0
0
ca
N M
O a)
L
CD N
E
(NJ
L
cn
a) U
0 0
U
O
(a
O_ U
.--. c
ti O
—
• =
> .`-.
C
to C
C
a) a)
v) a)
m 0
_U 0
� Z
O
0) ca
C U
0
U U
0
ca
O 0
a) Q
U fE
7 L
-0 0
C
0 L.L
O 0
_
ca 0
U) • C
C
E
ca =
CO Cr
Effluent data are from EPA Form 2C for Outfall 003 (04/01/21).
EPA Form 3510-2D (Revised 3-19)

This page intentionally left blank.

Form Approved 03/05/19
OMB No. 2040-0004
Check here if all pollutants listed in Table D are expected to be absent from your facility's discharge.
Check here if the facility believes it is exempt from Table D reporting requirements because it is a qualified small business. See the instructions for exemption criteria and for a list I
of materials you must attach to the application.
Note: If you check either of the above boxes, you do not need to complete Table D for the noted outfall unless you have quantitative data available.
1. Organic Toxic Pollutants (GC/MS Fraction —Volatile Compounds)
o
Z
❑ Yes ❑✓ No
❑ Yes ✓❑ No
o
Z
❑ Yes ❑✓ No
❑ Yes ❑✓ No
❑ Yes ❑✓ No
❑ Yes ❑✓ No
0
Z
❑ Yes ❑ No
❑ Yes ❑✓ No
>
>
>
(I,
a)
>
C/"5
m
(r)
a)
›-
m
m
m
m
m
m
m
m
m
m
m
Facility Name 0utfall Number
Chemours Co -Fayetteville Works 004
<1.0
N
O
V
o
(0;
O
O
O
O
O
O
O
O
O
O
O
O
<0.10
O
O
Believed Believed Units
Present Absent
ug/L
J
CD
7
J
Cr)
7
ug/L
ug/L
ug/L
ug/L
J
O)
7
J
a)
7
ug/L
ug/L
Concentration
Mass
Concentration
Mass
Concentration
Mass
Concentration
Mass
Concentration
Mass
Concentration
Mass
Concentration
Mass
Concentration
Mass
Concentration
Mass
Concentration
Mass
Concentration
Mass
0
0
0
0
0
0
0
0
0
■
0
❑
❑
❑II
❑II
M
II
M
M
EPA Identification Number
NCD 047 368 642
Acrolein
(107-02-8)
Acrylonitrile
(107-13-1)
Benzene
(71-43-2)
Bromoform
(75-25-2)
Carbon tetrachloride
(56-23-5)
Chlorobenzene
(108-90-7)
Chlorodibromomethane
(124-48-1)
Chloroethane
(75-00-3)
2-chloroethylvinyl ether
(110-75-8)
Chloroform (67-66-3)
Dichlorobromomethane
(75-27-4)
M
CO
I�
cc!
co,N
■
■
Effluent data are from EPA Form 2C for Outfall 003 (04/01/21).
EPA Form 3510-2D (Revised 3-19)

Form Approved 03/05/19
OMB No. 2040-0004
❑ Yes ❑✓ No
✓❑ Yes ❑ No
❑ Yes ✓❑ No
❑ Yes ✓❑ No
❑ Yes ✓❑ No
❑ Yes ✓❑ No
✓❑ Yes ❑ No
❑✓ Yes ❑ No
❑ Yes ❑✓ No J
❑ Yes ✓❑ No
❑ Yes ✓❑ No
✓❑ Yes ❑ No
0
Z
ti
CD
>—
m
m
m
m
cn
m
m
m
m
m
m
cn
m
Facility Name 0utfall Number
Chemours Co -Fayetteville Works 004
<0.10
0
M
0
V
0
N
0
V
0
N
0
V
<0.08
0
.--I
O
V
0
.--I
O
V
0
M
O
V
0
M
0
V
N
0
0
V
0
N
0
V
In
0
O
V
O
.--I
O
V
Believed Believed Units
Present Absent
ug/L
ug/L
ug/L
ug/L
ug/L
ug/L
ug/L
ug/L
ug/L
ug/L
J
M
D
ug/L
ug/L
Concentration
N
N
ca
M
Concentration
Mass
Concentration
Mass
Concentration
Mass
Concentration
Mass
Concentration J
Mass
Concentration J
Mass
Concentration
Mass
Concentration
Mass
Concentration
Mass
Concentration
Mass
Concentration
Mass
Concentration
Mass
0
.
0
0
0
0
.
.
0
0
0
.
0
❑
■
■
■
■
■
0
0
■
■
■
s
EPA Identification Number
NCD 047 368 642
1,1-dichloroethane
(75-34-3)
1,2-dichloroethane
(107-06-2)
1,1-dichloroethylene
(75-35-4)
1,2-dichloropropane
(78-87-5)
1,3-dichloropropylene
(542-75-6)
Ethylbenzene
(100-41-4)
Methyl bromide
(74-83-9)
Methyl chloride
(74-87-3)
Methylene chloride
(75-09-2)
1,1,2,2-tetrachloroethane
(79-34-5)
CD
C
CD
T
0
O
p
ao
O .,—
s— ti
N N
H
M
N ao
N a0
7 CO
O O
H
1,2-trans-dichloroethylene
(156-60-5)
N
CO
V
LC)
CO
I—
CO
6)
C)
N
N
N
N
CO
N
V
N
Effluent data are from EPA Form 2C for Outfall 003 (04/01/21).
EPA Form 3510-2D (Revised 3-19)

Form Approved 03/05/19
OMB No. 2040-0004
O
Z
>
ti
a)
>-
❑
O
Z
>
ti
a)
>-
❑
❑ Yes ❑✓ No
❑✓ Yes ❑ No
2. Organic Toxic Pollutants (GC/MS Fraction —Acid Compounds)
❑ Yes ❑✓ No
❑ Yes ❑✓ No
❑ Yes ❑✓ No
❑ Yes ❑✓ No
❑ Yes ❑✓ No
❑ Yes ❑✓ No
❑ Yes ❑✓ No
❑ Yes ❑✓ No
❑ Yes ❑✓ No
m
m
m
m
m
m
m
m
m
m
m
m
m
Facility Name Outfall Number
Chemours Co -Fayetteville Works 004
o
O
v
o
O
v
O
O
v
O
O
v
o
O
v
O
O
v
O
O
vV
O
c I
O
c-I
Vv
O
Ov
<0.30
<0.81
Believed Believed Units
Present Absent
J
co
7
ug/L
ug/L
J
to
7
ug/L
ug/L
ug/L
ug/L
ug/L
ug/L
ug/L
ug/L
ug/L
Concentration J
Mass
Concentration
Mass
Concentration
Mass
Concentration
Mass
Concentration
Mass
Concentration
Mass
Concentration
Mass
Concentration
Mass
Concentration
Mass
Concentration
Mass
Concentration
Mass
Concentration
Mass
Concentration
Mass
0
0
E
E
0
ia
0
0
0
0
El
0
EPA Identification Number
NCD 047 368 642
1,1,1-trichloroethane
(71-55-6)
1,1,2-trichloroethane
(79-00-5)
Trichloroethylene
(79-01-6)
Vinyl chloride
(75-01-4)
2-chlorophenol
(95-57-8)
2,4-dichlorophenol
(120-83-2)
2,4-dimethylphenol
(105-67-9)
4,6-dinitro-o-cresol
(534-52-1)
2,4-dinitrophenol
(51-28-5)
2-nitrophenol
(88-75-5)
4-nitrophenol
(100-02-7)
p-chloro-m-cresol
(59-50-7)
O
C
a>
0
O_
O
O
L L0
O 6
(E co
C ti
a)C°
_
N
N
("l
CO
("l
V
CV
LO
CV
CO
N
N-
("l
CO
(V
0)
("l
LO
N
CO
N
I--
N
CO
N
s—
0
0)
m
a
Effluent data are from EPA Form 2C for Outfall 003 (04/01/21).
EPA Form 3510-2D (Revised 3-19)

Form Approved 03/05/19
OMB No. 2040-0004
❑ Yes ❑✓ No
❑ Yes ❑✓ No
13. Organic Toxic Pollutants (GC/MS Fraction —Base /Neutral Compounds)
✓❑ Yes ❑ No
O
z
co
0
>-
❑✓ Yes ❑ No
O
z
>
co
0
>-
❑✓ Yes ❑ No
✓❑ Yes ❑ No
❑✓ Yes ❑ No
0
z
co
0
>-
❑✓ Yes ❑ No
❑ Yes ❑✓ No
❑ Yes ❑✓ No
m
m
m
m
m
m
m
m
m
m
m
m
m
Facility Name Outfall Number
Chemours Co -Fayetteville Works 004
<0.40 1
O
O
N
O
d
v
<0.081
1
O
O
v
c-I
v
csl 0
O
0
N
O
0
N
O
<0.10
<0.10
0
Csl
O
<0.10
Believed Believed Units
Present Absent
ug/L
ug/L
7
ug/L
ug/L
ug/L
ug/L
ug/L
ug/L
ug/L
ug/L
ug/L
ug/L
Concentration
Mass
Concentration
N
N
cca
Concentration
Mass
Concentration
Mass
Concentration
Mass
Concentration
Mass
Concentration
Mass
Concentration
Mass
Concentration
Mass
Concentration
Mass
Concentration
Mass
Concentration
Mass
Concentration
Mass
El
El
■
El
■
El
■
■
■
El
■
El
Ei
Ei
■
0
■
>
>
El
■
El
■
❑
■
■
EPA Identification Number
NCD 047 368 642
Phenol
(108-95-2)
2,4,6-trichlorophenol
(88-05-2)
Acenaphthene
(83-32-9)
Acenaphthylene
(208-96-8)
Anthracene
(120-12-7)
Benzidine
(92-87-5)
Benzo (a) anthracene
(56-55-3)
Benzo (a) pyrene
(50-32-8)
3,4-benzofluoranthene
(205-99-2)
Benzo (ghi) perylene
(191-24-2)
Benzo (k) fluoranthene
(207-08-9)
Bis (2-chloroethoxy) methane
(111-91-1)
Bis (2-chloroethyl) ether
(111-44-4)
M
N
M
CO
M
V
M
M
CO
M
M
CO
M
a)
M
M
M
N
N
Effluent data are from EPA Form 2C for Outfall 003 (04/01/21).
EPA Form 3510-2D (Revised 3-19)

Form Approved 03/05/19
OMB No. 2040-0004
❑ Yes ❑✓ No
0
Z
❑ Yes ❑✓ No
❑ Yes ❑✓ No
0
z
❑ Yes ❑✓ No
0
z
co
>-
0
z
0
z
0
z
0
z
0
z
0
Z
0
z
co
>-
co
>-
(/)
>-
U)
>-
co
>-
U)
>-
co
>-
co
>-
(/)
>-
m
m
m
m
m
m
m
m
m
m
m
m
m
m
Facility Name 0utfall Number
Chemours Co -Fayetteville Works 004
O
rnO vV
O
O r.i0
OCV
vV
1
O
O
O
O
O
O
O
0
O
<0.10
O
O
<0.30
<0.30
Ln
O
Believed Believed Units
Present Absent
ug/L
ug/L
ug/L
ug/L
ug/L
ug/L
ug/L
ug/L
ug/L
ug/L
ug/L
ug/L
J
bp
7
ug/L
Concentration
Mass
Concentration
Mass
Concentration
Mass
Concentration
Mass
Concentration
Mass
Concentration
Mass
Concentration
Mass
Concentration
Mass
Concentration
Mass
Concentration
Mass
Concentration
Mass
Concentration
Mass
Concentration
Mass
Concentration
Mass
El
E
E
E
E
El
■
IE
E
El
E
El
El
El
■
■
■
■
■
■
■
■
■
EPA Identification Number
NCD 047 368 642
Bis (2-chloroisopropyl) ether
(102-80-1)
Bis (2-ethylhexyl) phthalate
(117-81-7)
4-bromophenyl phenyl ether
(101-55-3)
Butyl benzyl phthalate
(85-68-7)
2-chloronaphthalene
(91-58-7)
4-chlorophenyl phenyl ether
(7005-72-3)
Chrysene
(218-01-9)
Dibenzo (a,h) anthracene
(53-70-3)
1,2-dichlorobenzene
(95-50-1)
1,3-dichlorobenzene
(541-73-1)
1,4-dichlorobenzene
(106-46-7)
3,3-dichlorobenzidine
(91-94-1)
Diethyl phthalate
(84-66-2)
Dimethyl phthalate
(131-11-3)
M
co
M
M
�
M
(0
M
N-
M
CO
M
0-3O
M
N
M
N
M
N
N
M
M
N
M
-
N
M
LC)
LC).-
N
M
Effluent data are from EPA Form 2C for Outfall 003 (04/01/21).
EPA Form 3510-2D (Revised 3-19)

Form Approved 03/05/19
OMB No. 2040-0004
o
z
cl))
>-
o
z
a`) ))
>-
0
z
a`) ))
>-
0
z
co
>-
0
z
co
>-
❑✓ Yes ❑ No
✓❑ Yes ❑ No
❑ Yes ❑✓ No
❑ Yes ✓❑ No
0
z
co
>-
0
z
m
>-
0
z
co
>-
0
z
Cl))
>-
✓❑ Yes ❑ No
m
rn
m
m
m
m
rn
m
m
m
m
m
m
m
Facility Name Outfall Number
Chemours Co -Fayetteville Works 004
0
`-i
0
ti
O
0
N
d
Lf)
O
0
ci
d
0
N
O
0
N
O
u')
d
0
N
O
0
N
O
<0.10
0
N
O
0
N
O
0
.--I
O
Believed Believed Units
Present Absent
ug/L
ug/L
ug/L
ug/L
ug/L
ug/L
ug/L
ug/L
ug/L
ug/L
ug/L
ug/L
J
Oq
0
ug/L
Concentration
Mass
Concentration
Mass
Concentration
Mass
Concentration
Mass
Concentration
Mass
Concentration
Mass
Concentration
Mass
Concentration
Mass
Concentration
Mass
Concentration
Mass
Concentration
Mass
Concentration
Mass
Concentration
Mass
Concentration
Mass
E
E
E
El
Ei
.
.
IE
El
El
El
Ei
0
■
■
■
❑
❑
•
Ei
,
❑
❑
■
■
■
■
Ei
EPA Identification Number
NCD 047 368 642
Di-n-butyl phthalate
(84-74-2)
2,4-dinitrotoluene
(121-14-2)
2,6-dinitrotoluene
(606-20-2)
Di-n-octyl phthalate
(117-84-0)
1,2-diphenylhydrazine
(as azobenzene) (122-66-7)
Fluoranthene
(206-44-0)
Fluorene
(86-73-7)
Hexachlorobenzene
(118-74-1)
N
0
N
co
0
O_
O M
O CO
(O CO
X ti
N CO
2
Hexachlorocyclopentadiene
(77-47-4)
Hexachloroethane
(67-72-1)
Indeno (1,2,3-cd) pyrene
(193-39-5)
Isophorone
(78-59-1)
Naphthalene
(91-20-3)
CO
N
M
I-
N
M
00
N
M
0)
N
M
O
CO
M
CO
M
N
CO
M
M
M
M
V
CO
M
LC)
CO
M
CO
CO
M
N-
CO
M
CO
CO
M
0)
CO
M
EPA Form 3510-2D (Revised 3-19)
Effluent data are from EPA Form 2C for Outfall 003 (04/01/21).

Form Approved 03/05/19
OMB No. 2040-0004
0
Z
a)
>-
❑ Yes ❑✓ No
❑ Yes ❑✓ No
❑ Yes ❑✓ No
❑✓ Yes ❑ No
❑✓ Yes ❑ No
❑ Yes ❑✓ No
14.Organic Toxic Pollutants (GC/MS Fraction —Pesticides)
❑ Yes ❑✓ No
❑ Yes ❑✓ No
❑ Yes 0 No
❑ Yes 0 No
❑ Yes 0 No
❑ Yes 0 No
m
m
m
m
m
m
m
m
m
m
m
m
m
Facility Name Outfall Number
Chemours Co -Fayetteville Works 004
O
0
O
O
O
00
O
O
<0.24
NI o
O
v
<0.40
o
O
<0.10
O
O
O
O
O
O
Believed Believed Units
Present Absent
ug/L
ug/L
ug/L
ug/L
ug/L
ug/L
J
OD
7
ug/L
ug/L
ug/L
ug/L
ug/L
ug/L
Concentration
Mass
Concentration
Mass
Concentration
Mass
Concentration
Mass
Concentration
Mass
Concentration
Mass
Concentration
Mass
Concentration
Mass
Concentration
Mass
Concentration
Mass
Concentration
Mass
Concentration
Mass
Concentration
Mass
E
E
E
El
■
■
El
IE
E
0
Ei
Ei
E
■
■
❑
❑
>.
El
■
❑
❑
■
■
■
❑
EPA Identification Number
NCD 047 368 642
Nitrobenzene
(98-95-3)
0
C
(o
T
L
E)
o
Oi LC)
co
N-nitrosod i-n-propylamine
(621-64-7)
N-nitrosodiphenylamine
(86-30-6)
Phenanthrene
(85-01-8)
Pyrene
(129-00-0)
1,2,4-trichlorobenzene
(120-82-1)
N
O
O
= 0)
Q
a-BHC
(319-84-6)
R-BHC
(319-85-7)
y-BHC
(58-89-9)
6-BHC
(319-86-8)
Chlordane
(57-74-9)
N
CO
LO
CO
O
M
C)
N
M
M
Cr)
V
M
Lf)
C)
CO
C`')
LO
0)
0_
a
EPA Form 3510-2D (Revised 3-19)
Effluent data are from EPA Form 2C for Outfall 003 (04/01/21).

Form Approved 03/05/19
OMB No. 2040-0004
❑ Yes ❑✓ No
0
z
❑ Yes ❑✓ No
0
z
❑ Yes ❑✓ No
❑ Yes ❑✓ No
❑ Yes ❑✓ No
❑ Yes ❑✓ No
0
z
>
>
>
a)
>-
m
>-
m
>-
m
m
m
m
m
m
m
m
m
Facility Name 0utfall Number
Chemours Co -Fayetteville Works 004
0
O
O
<0.020
N
00
O
<0.0082
I
00
O
0
O
0
0
O
0
N
00
O
<0.0093
Believed Believed Units
Present Absent
ug/L
ug/L
ug/L
ug/L
ug/L
ug/L
J
7
ug/L
J
7
Concentration
Mass
Concentration
Mass
Concentration
Mass
Concentration
Mass
Concentration
Mass
Concentration
Mass
Concentration
Mass
Concentration
Mass
Concentration
Mass
13
El
El
El
El
El
El
121
El
❑
❑
❑
■
■
■
■
■
■
EPA Identification Number
NCD 047 368 642
4,4'-DDT
(50-29-3)
4,4'-DDE
(72-55-9)
4,4'-DDD
(72-54-8)
Dieldrin
(60-57-1)
a-endosulfan
(115-29-7)
C
CO
7 ti
O)
O N
-o i
0 Lc)
Endosulfan sulfate
(1031-07-8)
Endrin
(72-20-8)
Endrin aldehyde
(7421-93-4)
Effluent data are from EPA Form 2C for Outfall 003 (04/01/21).
EPA Form 3510-2D (Revised 3-19)

Form Approved 03/05/19
OMB No. 2040-0004
❑ Yes ❑✓ No I
❑✓ Yes ❑ No
❑ Yes ❑✓ No
❑ Yes ❑✓ No
❑ Yes ❑✓ No
❑ Yes ❑✓ No
0
z
❑ Yes ❑✓ No
o
z
0
z
a)
>-
a>
>-
m
>-
m
m
m
m
m
m
m
m
m
m
Facility Name 0utfall Number
Chemours Co -Fayetteville Works 004
<0.0082 J
o
0
O
0
v
<0.076
<0.076
<0.076
O
0
v
O
0
v
O
o
v
m
0
v
Believed Believed Units
Present Absent
ug/L
ug/L
ug/L
ug/L
ug/L
ug/L
ug/L
ug/L
ug/L
ug/L
Concentration
Mass
Concentration
Mass
Concentration
Mass
Concentration
Mass
Concentration
Mass
Concentration
Mass
Concentration
Mass
Concentration
Mass
Concentration
Mass
Concentration
Mass
0
■
0
El
0
0
0
El
0
0
EPA Identification Number
NCD 047 368 642
Heptachlor
(76-44-8)
Heptachlor epoxide
(1024-57-3)
PCB-1242
(53469-21-9)
PCB-1254
(11097-69-1)
PCB-1221
(11104-28-2)
PCB-1232
(11141-16-5)
PCB-1248
(12672-29-6)
PCB-1260
(11096-82-5)
PCB-1016
(12674-11-2)
Toxaphene
(8001-35-2)
.-
s-
N
N
N
N
N
N
0
0)
a`>
E
co
0
c
(o
c
0
0
0
co
c
(a
c
0
0
0
co
(o
(o
a)
L
(0
c
LL
U
0
0
0
a- >
O
0
0
(o
U) M
O
O ▪ N
E (v
N
0
U LJ
a> U
0 0
-0 v
U
O co
O_ CO
ti C
O
N
U) C
C .-
O a)
v) a)
T U)
m ▪ 0
U O
� Z
Q
CD co
U
0
U N
U
(a
O 0
Q
U (E
7 -
-0 U
C ct
0 L.L
a> U
_o o
=
(o 0
_cco 0
o
C
E
(o =
cr
Effluent data are from EPA Form 2C for Outfall 003 (04/01/21).
EPA Form 3510-2D (Revised 3-19)

This page intentionally left blank.

Outfall Number
0
0
Chemours Co -Fayetteville Works
EPA Identification Number
NCD 047 368 642
Reason Pollutant Believed Present in Discharge Available Quantitative Data
(specify units)
Check (V) here if you believe all pollutants listed to be absent from the discharge. You need not complete Table E for the noted outfall unless you have quantitative data available.
❑
❑
❑
❑
❑
❑
❑
❑
❑
❑
❑
❑
❑
❑
❑
❑
❑
❑
Z
a
I-
m
0
0
a
N
_
Z
ce
w
U
LLI
Lu
J
m
<
5
co
=
0
a
Asbestos
Acetaldehyde
Allyl alcohol
Allyl chloride
Amyl acetate
—
Q
Benzonitrile ]
Benzyl chloride
Butyl acetate
Butylamine
as
a
0
Carbaryl
Carbofuran
Carbon disulfide
o
o_
o
U
Coumaphos
Cresol
Crotonaldehyde
N
cd
4
LC)
CO
I—
co
6)
6
'4
cd
EPA Form 3510-2D (Revised 3-19)

Cr, V
O
O
O
M O
O
"0 N
a) .
O
Z
CL
0 00
E O
E
0
L
Outfall Number
0
0
0
Chemours Co -Fayetteville Works
EPA Identification Number
NCD 047 368 642
Available Quantitative Data
(specify units)
Reason Pollutant Believed Present in Discharge
❑
❑
❑
❑
❑
❑
❑
❑
❑
❑
❑
❑
❑
❑
❑
❑
❑
❑
❑
❑
❑
❑
❑
❑
❑
❑
❑
❑
❑
❑
❑
❑
❑
❑
❑
❑
❑
❑
Z
a
I—
Cfl
0
0
ce
a
N
_
Z
I—
W
w
0
LLI
LLI J
m
Q
F-
E-
as
=
o
a
19. Cyclohexane ]
120. 2,4-D (2,4-dichlorophenoxyacetic acid)
o
c
o
22. Dicamba
23. Dichlobenil
24. Dichlone
25. 2,2-dichloropropionic acid
26. Dichlorvos ]
27. Diethyl amine
28. Dimethyl amine
29. Dintrobenzene
30. Diquat
0
o
E
32. Diuron
33. Epichlorohydrin
c
o
W
135. Ethylene diamine
36. Ethylene dibromide
37. Formaldehyde
N
M
4
CO
0
N
a)
0)
a)
d
EPA Form 3510-2D (Revised 3-19)

O
�
M O
O
"CS N
N .
O
Z
CL
0 00
E O
0
LL
Outfall Number
0
0
Chemours Co -Fayetteville Works
EPA Identification Number
NCD 047 368 642
Available Quantitative Data
(specify units)
Reason Pollutant Believed Present in Discharge
❑
❑
❑
❑
❑
❑
❑
❑
❑
❑
❑
❑
❑
❑
❑
❑
❑
❑
❑
❑
❑
❑
❑
❑
❑
❑
❑
❑
❑
❑
❑
❑
❑
❑
❑
❑
❑
❑
Z
a
I—
m
0
0
ce
a
N
_
Z
w
U
LLI
LLI J
m
1-
E-
as
=
O
a
Furfural
Guthion
Isoprene
Isopropanolamine
Kelthane
Kepone
Malathion
Mercaptodimethur ]
Methoxychlor
Methyl mercaptan
Methyl methacrylate
Methyl parathion
Mevinphos
a)
0
0
x
a)
Monoethyl amine
Monomethyl amine
0
a)
a
Z
Naphthenic acid
Nitrotoluene
co
M
d-
d-
d-
d-
d-
d-
d-
d-
d-
d-
LC)
LC)
LNC)
LC)
L(C)
LC)
1!)
0)
CL
EPA Form 3510-2D (Revised 3-19)

Cr, V
O
O
O
M O
O
N
N .
O
Z
CL
0 00
E O
0
LI
Outfall Number
0
0
0
Chemours Co -Fayetteville Works
EPA Identification Number
NCD 047 368 642
Available Quantitative Data
(specify units)
Reason Pollutant Believed Present in Discharge
❑
❑
❑
❑
❑
❑
❑
❑
❑
❑
❑
❑
❑
❑
❑
❑
❑
❑
❑
❑
❑
❑
❑
❑
❑
❑
❑
❑
❑
❑
❑
❑
❑
❑
❑
❑
❑
❑
Z
a
I—
CI)
m
0
0
CC
a
N
2
Z
w
0
W
LLIJ
m
<
as
=
p
a
Parathion
0
S
o
(
o
a)
la_0
Phosgene
Propargite
Propylene oxide
Pyrethrins
c
o
•c
2
o
Q'
Strontium
Strychnine
Styrene
2,4,5-T (2,4,5-trichlorophenoxyacetic
acid)
TDE (tetrachlorodiphenyl ethane)
2,4,5-TP [2-(2,4,5-trichlorophenoxy)
propanoic acid]
0
2
o
0
H
Triethanolamine
Triethylamine
Trimethylamine
Uranium
C) I--:00
L
LO
0)
LC)
=•
CO
CO
N
CO
C)
CO
4
CO
Li)
CO
(O
CO
I-
CO
00
CO
0)
co
=•
f-
-
I -
N
N-
C)
ti
ti
ti
N
N
0
O
0_
0
EPA Form 3510-2D (Revised 3-19)

Outfall Number
V
O
O
Chemours Co -Fayetteville Works
EPA Identification Number
NCD 047 368 642
Available Quantitative Data
(specify units)
Reason Pollutant Believed Present in Discharge
❑
❑
❑
❑
❑
Z
H
m
N
N
0
0
ce
N
_
Z
H
d'
W
U
uj
MI
CO
H
<a
=
O
a
Vanadium
Vinyl acetate
c
a)
X
c
a)
X
Zirconium
N-
ti
cd
1
co
O
a)
N
E
co
n
c
c
0
0
0
c
c
0
0
0
co
T
ca
a)
L
co
LL
0
0
0
0
a- )
O
n
n
0
U) M
O CD
-C
O N
E
N
a)
LL
a) 0
U
O ca
Q co
C
yO+ O
O
U) C
a) a)
(0 a)
m 0
_U O
Z
O �
Q
01 CD
U
O
U N
0
C6 0
— N
a) Q
U fE
7 _C
-0 0
C
0 LL
L.L
a) 0
_
=
_c0
c
Cr)
c �
-• o
E
(E
• 0-
a)
Effluent data are from EPA Form 2C for Outfall 003.
EPA Form 3510-2D (Revised 3-19)

Attachment A.2 — Line Drawing Water Balance

Chemours Company - Fayetteville Works Groundwater Treatment System
ATTACHMENT A.02
OUTFALL 004 FORM 2C SECTION 2 : LINE DRAWING
WATER BALANCE (06-10-2021)
Groundwater
from Black
Creek Aquifer
& Surficial
Baseflow and
Surface Runoff
from Seeps A
&B
Cape Fear River
950 gpm
269 gpm
Groundwater
Treatment
System (GWTS)
•
NOTES:
1) gpm = gallons per minute
2) All flow rates are estimated maximum daily discharges.
1,219 gpm"" --►
12,517 gpm
•
Outfall 002
June 2021

Attachment A.3 — Rationale for Presence of
Compounds in Intake Water

Chemours Company - Fayetteville Works
Groundwater Treatment System
Attachment A.3
Form 2D Attachment - Justification for Presence of Pollutants
The pollutants below were identified as being present in the intake water (influent) to the Groundwater Treatment
System (GWTS).
The effluent concentrations and presence/absence on EPA Form 2D are from EPA Form 2C for Outfall 003 from the
April 1, 2021 submittal.
Parameter Name
Rationale for Presence
Table A. Conventional and Non -conventional Parameters (40 CFR 122.21(k)(5)(i))
Biochemical oxygen demand
Detected in Outfall 003
Chemical oxygen demand
Detected in seep (Mar/Apr 2021)
Total organic carbon
Detected in groundwater (GW) and seeps (Mar/Apr 2021)
Total suspended solids
Detected in GW and seeps (2018-2020 data)
Ammonia
Detected in GW and seeps (2018-2020 data)
pH
Detected in GW and seeps (Mar/Apr 2021)
Table B. Certain Conventional and Non -conventional parameters (40 CFR 122.21(k)(5)(ii),
Chlorine (total Residual)
Detected in GW and seeps (Mar/Apr 2021)
Color
Detected in GW and seeps (Mar/Apr 2021)
Fecal Coliform
Detected in GW and seeps (2018-2020 data)
Fluoride (16984-48-8)
Detected in GW and seeps (Mar/Apr 2021)
Nitrate -Nitrite
Detected in GW and seeps (Mar/Apr 2021)
Nitrogen (total Organic as N)
Engineering judgment
Oil and grease
Detected in Outfall 003
Phosphorous (as P), Total (7723-14-0)
Detected in GW and seeps (2018-2020 data)
Sulfate (as SO4) (14808-79-8)
Detected in GW and seeps (Mar/Apr 2021)
Sulfide
Detected in GW and seeps (2018-2020 data)
Aluminum, Total (7429-90-5)
Detected in GW and seeps (Mar/Apr 2021)
Barium, Total (7440-39-3)
Detected in GW and seeps (Mar/Apr 2021)
Boron, Total (7440-42-8)
Detected in seep (Mar/Apr 2021)
Cobalt, Total (7440-48-4)
Detected in GW and seeps (Mar/Apr 2021)
Iron, Total (7439-89-6)
Detected in GW and seeps (Mar/Apr 2021)
Magnesium, Total (7439-95-4)
Detected in GW and seeps (Mar/Apr 2021)
Manganese, Total (7439-96-5)
Detected in GW and seeps (Mar/Apr 2021)
Titanium, Total (7440-32-6)
Detected in GW and seeps (Mar/Apr 2021)
Alpha, Total
Detected in seeps (2018-2020)
Beta, Total
Detected in seeps (2018-2020)
Radium, Total
Detected in GW and seeps (Mar/Apr 2021)
Radium 226, Total
Detected in GW and seeps (Mar/Apr 2021)
Table C. Toxic Metals, Total Cyanide, and Total Phenols (40 CFR 122.21(k)(5)(iii)(A))
Arsenic
Detected in GW and seeps (Mar/Apr 2021)
Beryllium
Detected in GW and seeps (Mar/Apr 2021)
Chromium
Detected in GW and seeps (Mar/Apr 2021)
Page 1 of 2
June 2021

Chemours Company - Fayetteville Works
Groundwater Treatment System
Parameter Name
Rationale for Presence
Copper
Detected in GW and seeps (Mar/Apr 2021)
Lead
Detected in GW and seeps (Mar/Apr 2021)
Mercury
Detected in seeps (Mar/Apr 2021)
Nickel
Detected in seeps (Mar/Apr 2021)
Selenium
Detected in seeps (2018-2020 data)
Zinc
Detected in seeps (Mar/Apr 2021)
Cyanide
Detected in seeps (Mar/Apr 2021)
Table D.1 Organic Toxic Pollutants (GC/MS Fraction - Volatile Compounds)
Chloroform
Detected in GW (2018-2020 data)
1,2-dichloroethane
Detected in GW (2018-2020 data)
Methyl bromide
Detected in GW (2018-2020 data)
Methyl chloride
Detected in GW (2018-2020 data)
Toluene
Detected in GW (2018-2020 data)
Vinyl chloride
Detected in GW and seeps (Mar/Apr 2021)
rTable D.2 Organic Toxic Pollutants (GC/MS Fraction - Base/Neutral Compounds)
Acenapthene
Detected in GW (Mar/Apr 2021)
Anthracene
Detected in GW (Mar/Apr 2021)
Benzo(a)Anthracene
Detected in GW (Mar/Apr 2021)
Benzo(a)Pyrene
Detected in GW (Mar/Apr 2021)
Benzo(b)Fluoranthene
Detected in GW (Mar/Apr 2021)
Benzo(K)Fluoranthene
Detected in GW (Mar/Apr 2021)
Chrysene
Detected in GW (Mar/Apr 2021)
Fluoranthene
Detected in GW (Mar/Apr 2021)
Fluorene
Detected in GW (Mar/Apr 2021)
Napthalene
Detected in GW (Mar/Apr 2021)
Phenanthrene
Detected in GW (Mar/Apr 2021)
Pyrene
Detected in GW (Mar/Apr 2021)
Table D.4 Organic Toxic Pollutants (GC/MS Fraction - Pesticides)
Heptachlor epoxide
Detected in GW and seeps (2018-2020 data)
Page 2 of 2 June 2021

Attachment A.4 -Groundwater and Seeps Water
Quality Assessment

GeosynIec(>
consultants
Geosyntec Consultants of NC, P.C.
NC License No.: C-3500 and C-295
Memorandum
2501 Blue Ridge Road, Suite 430
Raleigh, NC 27607
PH 919.870.0576
FAX [phone]
www.geosyntec.com
Date: June 13, 2021
To: Chemours Company FC, LLC
Subject: Chemours Fayetteville Works — Groundwater and Seeps Water Quality
Assessment
1 INTRODUCTION
Geosyntec Consultants of NC, P.C. (Geosyntec) has prepared this memorandum for The
Chemours Company FC, LLC (Chemours). This document summarizes a water quality
assessment of groundwater and seep data intended to represent the influent to a
groundwater extraction and treatment system (Groundwater Treatment System or
GWTS). The GWTS is a requirement of the Addendum to Consent Order paragraph 12
(CO Addendum) amongst Chemours, the North Carolina Department of Environmental
Quality (NCDEQ), and Cape Fear River Watch entered by the court on October 12, 2020.
The GWTS will discharge to the pipe that conveys the effluent from Outfall 002 at the
Fayetteville Works site to the Cape Fear River. The discharge will enter the pipe
approximately 870 feet downstream of Outfall 002 and is expected to be designated as
Outfall 004. The combined discharge from Outfalls 002 and 004 will then enter the river.
As part of the National Pollutant Discharge Elimination System (NPDES) permit
application for the GWTS, Chemours is required to complete EPA Application Form 2D
New Manufacturing, Commercial, Mining, and Silvicultural Operations That Have Not
Yet Commenced Discharge of Process Wastewater. EPA Form 2D requires information
on whether a compound is believed present in the intake water for the treatment system
and the maximum concentrations expected in the treatment system discharge for a
number of different compounds. This water quality assessment was conducted to provide
this information. Results are summarized herein. For compounds where the averages of
the untreated groundwater and seeps water were calculated to be greater than a water
quality criterion, information has been incorporated into the Engineering Report
(Geosyntec, 2021).
TR0795A108D102/A-04a Chemours FW 004 - Form 2C - Att 4 GWTS WQ Assessment - 06-13-2021.docx

Groundwater and Seeps Water Quality Assessment
June 13, 2021
Page 2
2 SAMPLING PROGRAMS
Geosyntee
consultants
(;eosyneec Consultants of NC, RC,
NC Ucense Na.: C-35Ot and C•2,45
Data from untreated groundwater and seep sampling that occurred from 2018 through
2020 were evaluated to determine what compounds should be further sampled for
inclusion on the EPA Form 2D:
a) where any untreated groundwater or seep concentration was greater than North
Carolina's most stringent, applicable surface water quality criteria (including the
North Carolina 15A NCAC 02B Water Quality Standards for Surface Waters, US
EPA National Recommended Water Quality Criteria for Aquatic Life & Human
Health, and North Carolina In -Stream Target Values for Surface Waters);
b) where the reporting limits were greater than the applicable surface water quality
criteria; and
c) where data did not exist.
The evaluation of the 2018 through 2020 data was used to inform sampling that Chemours
conducted in March and April 2021. This untreated groundwater and seep sampling was
conducted to provide representative data to complete the intake information on EPA Form
2D and to inform the engineering analysis of the GWTS.
Figure 1 provides the locations of the 2018-2020 sampling and the March/April 2021
sampling. Figure 2 shows the location of the March/April 2021 sampling. This included
four groundwater locations (EW-1, EW-3, PIW-10S, and PIW-5S) and two seep locations
(SEEP -A -WALL and SEEP-B-WALL). Concentrations from SEEP-A-TR4 were not
included in the water quality assessment for EPA Form 2D as this sample was artificially
disturbed to produce results necessary for the engineering analysis.
3 2018 THROUGH 2020 SAMPLING RESULTS
The 2018 through 2020 sampling results include data from September 27, 2018 to
October 23, 2020. Table 1 provides the comparison of the 2018 to 2020 groundwater data
to the surface water quality criteria. Table 2 provides the comparison of the 2018 through
2020 seep data to the surface water quality criteria. Of the compounds that were analyzed,
the following had at least one result that was greater than the surface water quality criteria:
• Beryllium
• Fluoride
• Iron
• Lead
June 2021

Groundwater and Seeps Water Quality Assessment
June 13, 2021
Page 3
• Manganese
• Mercury
• Methyl bromide
• Radium, total
• Selenium
• Sulfide
• Total residual chlorine
Geosyntec
consultants
(;eosyneec Consultants of NC, RC,
NC Ucense Na.: C-35Ot and C•2,45
These parameters were analyzed in the March/April 2021 sampling program. A number
of compounds had insufficient reporting limits for comparison to the water quality criteria
and were also included in the March/April 2021 sampling program. Additionally, some
parameters on the EPA 2D Form had not previously be analyzed for in the untreated
groundwater or seeps and were therefore included for analysis in the March/April 2021
sampling program.
4 MARCH/APRIL 2021 SAMPLING RESULTS
Samples for the March/April 2021 sampling were collected from the four representative
groundwater extraction wells and two seep locations. Sampling was conducted on March
3, 2021 for all parameters. Further samples were collected on additional dates in March
and April of 2021 based on the need determined by the 2018 through 2020 sampling
results or the requirements for the engineering study. Flow -weighted mean concentrations
(FWMCs) were calculated for each day based on the expected maximum daily flow from
each source, as shown in Table 3. Table 3 also includes the average daily discharge for
Outfall 002, which was used to provide an estimate of the combined concentration from
Outfall 002 and the GWTS, prior to discharge to the Cape Fear River.
4.1 Flow -weighted Mean Concentrations (FWMC)
Table 4 provides the concentrations for compounds where a single sample was collected,
along with an estimated load in pounds per day (lb/d) and a FWMC. For some
compounds, all of the concentrations were less than the reporting limit and it is assumed
that there is no reasonable potential for the GWTS discharge to cause or contribute to an
exceedance of the water quality criterion in the Cape Fear River. No additional evaluation
was performed on this data. When some of the concentrations were above the reporting
limit, the FWMC in Table 4 was calculated assuming concentrations below the reporting
limit were equal to the reporting limit.
June 2021

Groundwater and Seeps Water Quality Assessment
June 13, 2021
Page 4
Geosyntee
consultants
(;eosyneec Consultants of NC, RC,
NC Ucense Na.: C-35Ot and C•2,45
Table 5 provides the concentrations for compounds where multiple samples were
collected, along with an estimated load and a FWMC for each day. The load and FWMC
calculations were performed assuming that values less than the reporting limit were equal
to the reporting limit. For some pollutants, all of the concentrations were less than the
reporting limit and it is assumed that there is no reasonable potential for the GWTS
discharge to cause or contribute to an exceedance of the water quality criterion in the
Cape Fear River. No additional evaluation was performed for these data. If any of the
concentrations were above the reporting limit, an average load and FWMC was then
calculated across all of the sampling events.
4.2 Comparison to Surface Water Quality Criteria
As many of the results at individual wells or seeps were below the reporting limit,
FWMCs were calculated assuming concentrations below the reporting limit were set to
(1) the reporting limit, (2) one half of the reporting limit, and (3) zero. Table 6 (which
integrates information from Tables 4 and 5) shows the results of these calculations
compared to the surface water quality criteria. FWMCs that are greater than the water
quality criterion are highlighted.
For the highlighted compounds, calculations for iron and manganese were insensitive to
these varied assumptions about reporting limits and the estimated concentrations did not
change. The varied assumptions did result in decreases in the estimated concentrations of
total residual chlorine, cyanide, mercury, anthracene, fluoranthene, phenanthrene,
polycyclic aromatic hydrocarbons (PAHs), and heptachlor epoxide. PAHs included in the
analysis are benzo(A)anthracene, benzo(A)pyrene, benzo(B)fluoranthene,
benzo(K)fluoranthene, and chrysene.
The samples were analyzed for total chromium and total cyanide to meet the needs of the
EPA Form 2D; however, the criteria are for Chromium III and free cyanide, respectively.
The estimated total cyanide concentration met the free cyanide water quality criterion
when concentrations below the reporting limit were assumed to be equal to one-half of
the reporting limit or zero. The total chromium concentration met the Chromium III
criteria in all assumptions.
It should also be noted that EPA approved the removal of the North Carolina aquatic life
standards for both iron and manganese due to high natural occurrence in North Carolina's
surface waters. The iron and manganese concentrations are compared to the EPA National
Recommended Water Quality Criteria for Aquatic Life & Human Health in Table 6
strictly for guidance.
For the comprehensive Site permit application, Chemours conducted a mixing zone
assessment to determine that there was an 8:1 dilution available in the Cape Fear River
June 2021

Groundwater and Seeps Water Quality Assessment
June 13, 2021
Page 5
Geosyntec
consultants
Geosyntec Consultants of NC, Y.C,
KC Ucense Na.: C-35Ot and C•2,45
for Outfall 002 (Geosyntec, 2019). Table 7 provides the comparison of the FWMC for
Outfall 004 with the 8:1 dilution applied to the water quality criteria. Results indicate that
total residual chlorine, PAHs, and heptachlor epoxide may have reasonable potential to
exceed surface water quality criteria without treatment or mixing with effluent from
Outfall 002.
A mass balance was conducted using the loads calculated with the FWMC for Outfall
004 after mixing with the effluent from Outfall 002. An average daily flow of 18.025
million gallons per day (MGD) was used for Outfall 002, consistent with the line drawing
for the NPDES permit application submitted on June 4, 2021 (see Table 3).
Concentrations for Outfall 002 include the long-term average from EPA Form 2C (when
available) or the daily maximum. Table 8 provides the loads calculated for Outfalls 002
and 004.
Table 9 shows the mass balance for Outfalls 002 and 004 and mixing zone assessment
combined results for total residual chlorine, the PAHs, and heptachlor epoxide, as these
compounds were identified in Table 7 as possibly having have reasonable potential to
exceed surface water quality criteria. The results show that the total residual chlorine is
well below the criterion. Only heptachlor epoxide and PAHs therefore warrant
consideration as additional pollutants targeted for removal by the GWTS.
5 SUMMARY
Heptachlor epoxide was only detected in one well (PIW-5S) and one seep (SEEP -A -
WALL) at low levels. Heptachlor is a breakdown product of an insecticide that is not
used at the Site. The PAH compounds were only detected at low levels in one (PIW-5S)
of the six untreated groundwater and seep sources. There is no asphalt present nearby that
would serve as a source of PAHs. PAHs and heptachlor epoxide are also not present in
the wastewater from the manufacturing operations (see the EPA Form 2C for Outfall 002
with the NPDES permit application dated June 4, 2021). In addition, flow from the PIW-
5S well is only 7% of the total flow and flow from Seep -A -Wall is only 4% of the total
flow. Finally, the Chemours river intake, Outfall 002 and Outfall 003 analytical results
for these compounds were non -detect. Chemours intends to resample PIW-5S and SEEP -
A -WALL for PAHs and heptachlor epoxide.
As indicated in the Engineering Report (Geosyntec, 2021), it is anticipated that the GWTS
will reduce the contaminant levels of these potential pollutants so that the discharge from
Outfall 004 will not cause or contribute to exceedances of the surface water quality
criteria in the Cape Fear River, if they are present.
June 2021

Groundwater and Seeps Water Quality Assessment
June 13, 2021
Page 6
References
Geosyntec
consultants
(;eosyneec Consultants of NC, RC,
NC Ucense Na.: C-35Ot and C•2,45
Geosyntec, 2021. Engineering Report — Treatment of Groundwater and Upgradient Seeps
Water Prepared for the Chemours Company FC, LLC. June 10, 2021.
Geosyntec, 2019. Mixing Zone Report, Addendum. Chemours Fayetteville Works
Outfall 002, Fayetteville, North Carolina. Prepared for the Chemours Company FC, LLC.
October 2019.
June 2021

Locations Sampled along Barrier
Wall Alignment in March 2021
Onsite Surface Water and Groundwater
Sample Locations - Past 5 Years
Geosyntec'
consultants
Geosyntec Consultants of NC, P.C.
NC License No.: C 3500 and C 295
1

Legend
Locations Sampled along Barrier
Wall Alignment in March 2021
Surficial Aquifer
Monitoring Well Sample
Location
fib
`O
Via
Black Creek Aquifer
Monitoring Well Sample
Location
® Seep Sample Location
Seep Location — — — Observed Seep
Cape Fear River • Planned Groundwater Remedy Route
Nearby Tributary Site Boundary
400
200
0
400 Feet
Seep Sample Locations - Past 5 Years
Chemours Fayetteville Works, North Carolina
Notes:
1. Topographic surface was generated using LiDAR scans performed on December 1, 2019 and December 19, 2019
by Spectral Data Consultants, Inc
2. The outline of the River shown on this figure is approximate (River outline based on compilation of open data sources from ArcGIS
online service and North Carolina Department of Environmental Quality Online GIS - Major Hydro shapefile).
3. Basemap source: Esri, DigitalGlobe, GeoEye, Earthstar Geographics, CNES/Airbus DS, USDA, USGS, AeroGRID, IGN, and the
GIS User Community.
Geosyntec °
consultants
Geosyntec Consultants of NC, P.C.
NC License No.: C-3500 and C-295
Raleigh
June 2021
Figure
2

Table 1
Onsite Untreated Groundwater Data Summary for 2018 to 2020
Chemours Fayetteville Works, North Carolina
Geosyntec Consultants of NC P.C.
Parameter name (as used in data analysis)
CAS Number
Units
Minimum
Regulatory
Criteria
Greater Than
Criteria
(Y/N)
No. Total
Results
No. Total
of Detects
No. Total
Non-
Detects
Maximum
Minimum
Source Data
beginning
date
Source Data
end date
TABLE A. CONVENTIONAL AND NON CONVENTIONAL PARAMETER ESTIMATES (40 CFR 122.21(k)(5)())
Biochemical Oxygen Demand (BOD) - 5 Day
BOD
mg/L
NA
No
4
0
4
ND
ND
5/27/2020
5/28/2020
Chemical Oxygen Demand (COD)
COD
mg/L
NA
No
4
2
2
8.6
6.6
5/28/2020
5/28/2020
Total Organic Carbon
TOC
mg/L
NA
No
8
7
1
6.2
0.52
9/27/2018
5/28/2020
Total Suspended Solids
TSS
mg/L
NA
No
4
2
2
87
13
5/28/2020
5/28/2020
Ammonia
mg/L
pH and Temp
Dependent
No
4
2
2
2.7
2.7
5/27/2020
5/27/2020
TABLE B. CERTAIN CONVENTIONAL AND NON- CONVENTIONAL POLLUTANTS (40 CFR 122.21(k)(5)(ii))
Bromide
mg/L
NA
No
8
0
8
ND
ND
9/27/2018
5/28/2020
Fluoride (1698448-8)
16984-48-8
mg/L
1.8
Yes
8
3
5
5.1
0.033
9/27/2018
3/6/2020
Oil and Grease
mg/L
NA
No
4
0
4
ND
ND
5/27/2020
5/28/2020
Phosphorous (as P), Total (7723-14-0)
7723-14-0
mg/L
NA
No
4
3
1
0.099
0.04
5/27/2020
5/28/2020
Sulfate (as SO4) (14808-79-8)
14808-79-8
mg/L
250
No
8
8
0
68
3.5
9/27/2018
5/28/2020
Aluminum, Total (7429-90-5)
7429-90-5
mg/L
6.5
No
8
8
0
1.4
0.088
9/27/2018
5/28/2020
Barium, Total (7440-39-3)
7440-39-3
mg/L
1
No
4
4
0
0.057
0.043
5/27/2020
5/28/2020
Cobalt, Total (7440-48-4)
7440-48-4
mg/L
0.0016
No
4
3
1
0.00089
0.00071
5/27/2020
5/28/2020
Iron, Total (7439-89-6)
7439-89-6
mg/L
1
Yes
12
11
1
11
0.0487
9/27/2018
5/28/2020
Magnesium, Total (7439-95-4)
7439-95-4
mg/L
NA
No
8
8
0
5.1
0.39
9/27/2018
5/28/2020
Manganese, Total (7439-96-5)
7439-96-5
mg/L
0.05
Ycs
8
8
0
0.366
0.0041
9/27/2018
5/28/2020
Radioactivity
TABLE C. TOXIC METALS, TOTAL CYANIDE, AND TOTAL PHENOLS (40 CFR 122.21(k)(5)( ii)(A))1
Antimony
7440-36-0
mg/L
0.0056
No
4 0
4
ND
ND
5/27/2020
5/28/2020
Arsenic
7440-38-2
mg/L
0.01
No
4 1
3
0.0013
0.0013
5/28/2020
5/28/2020
Beryllium
7440-41-7
mg/L
0.0065
Yes
4 4
0
0.0067
0.00014
5/27/2020
5/28/2020
Cadmium
7440-43-9
mg/L
0.00042
No
4 0
4
ND
ND
5/27/2020
5/28/2020
Chromium
7440-47-3
mg/L
0.011
No
4 4
0
0.0055
0.0019
5/27/2020
5/28/2020
Copper
7440-50-8
mg/L
0.00896
No
4 4
0
0.0038
0.00064
5/27/2020
5/28/2020
Lead
7439-92-1
mg/L
0.00252
Yes
4 4
0
0.0029
0.00048
5/27/2020
5/28/2020
Mercury
7439-97-6
mg/L
0.000012
Yes
4 2
2
0.00019
0.00013
5/28/2020
5/28/2020
Nickel
7440-02-0
mg/L
0.025
No
4 4
0
0.0032
0.0011
5/27/2020
5/28/2020
Selenium
7782-49-2
mg/L
0.005
No
4 0
4
ND
ND
5/27/2020
5/28/2020
Silver
7440-22-4
mg/L
0.00006
No
4 0
4
ND
ND
5/27/2020
5/28/2020
Thallium
7440-28-0
mg/L
0.002
No
4 0
4
ND
ND
5/27/2020
5/28/2020
Zinc
7440-66-6
mg/L
0.11718
No
4 3
1
0.091
0.01
5/27/2020
5/28/2020
Organic Toxic Pollutants (GC/MS Fraction - Volatile Compounds)
TABLE D. ORGANIC TOXIC POLLUTANTS (Gas Chromatography/Mass Spectrometry or GC/MS Fractions) (40 CFR 122 21(k)(5)(iii)(B))
Acrolein
107-02-8
ug/L 3
No
28
0
28
ND
ND
5/2/2019
8/12/2019
Acrylonitrile
107-13-1
ug/L
0.061
No
28
0
28
ND
ND
5/2/2019
8/12/2019
Benzene
71-43-2
ug/L
1.19
No
32
0
32
ND
ND
5/2/2019
5/28/2020
Bromoform
75-25-2
ug/L
7
No
32
0
32
ND
ND
5/2/2019
5/28/2020
Carbon Tetrachloride
56-23-5
ug/L
0.254
No
32
0
32
ND
ND
5/2/2019
5/28/2020
Chlorobezene
108-90-7
ug/L
140
No
32
0
32
ND
ND
5/2/2019
5/28/2020
Chlorodibromomethane
124-48-1
ug/L
0.8
No
32
0
32
ND
ND
5/2/2019
5/28/2020
Ethyl Chloride
75-00-3
ug/L
NA
No
32
0
32
ND
ND
5/2/2019
5/28/2020
TR0795A
Page 1 of 28
June 2021

Table 1
Onsite Untreated Groundwater Data Summary for 2018 to 2020
Chemours Fayetteville Works, North Carolina
Geosyntec Consultants of NC P.C.
Parameter name (as used in data analysis)
CAS Number
Units
Minimum
Regulatory
Criteria
Greater Than
Criteria
(Y/N)
No. Total
Results
No. Total
of Detects
No. Total
Non-
Detects
Maximum
Minimum
Source Data
beginning
date
Source Data
end date
Chloroform
67-66-3
ug/L
60
! No
32
19
13
2
0.16
5/2/2019
8/12/2019
Dichlorobromomethane
75-27-4
ug/L
0.55
No
32
0
32
ND
ND
5/2/2019
5/28/2020
1,1-dichloroethane
75-34-3
ug/L
I 6
No
32
0
32
ND
ND
5/2/2019
5/28/2020
1,2-dichloroethane
107-06-2
ug/L
9.9
No
32
3
29
0.18
0.14
5/2/2019
5/3/2019
1,1-dichloroethylene
75-35-4
ug/L
300
No
32
0
32
ND
ND
5/2/2019
5/28/2020
1,2-dichloropropane
78-87-5
ug/L
0.9
No
32
0
32
ND
ND
5/2/2019
5/28/2020
Ethylbenzene
100-41-4
ug/L
68
No
32
0
32
ND
ND
5/2/2019
5/28/2020
Methyl bromide
74-83-9
ug/L
0.04
Yes
32
1
31
0.3
0.3
8/9/2019
8/9/2019
Methyl chloride
74-87-3
ug/L
2.6
No
32
1
31
0.41
0.41
6/18/2019
6/18/2019
Methylene chloride
75-09-2
ug/L
20
No
32
0
32
ND
ND
5/2/2019
5/28/2020
1,1,2,2-tetrachloroethane
79-34-5
ug/L
0.17
No
32
0
32
ND
ND
5/2/2019
5/28/2020
Tetrachloroethylene
127-18-4
ug/L
0.7
No
32
0
32
ND
ND
5/2/2019
5/28/2020
Toluene
108-88-3
ug/L
11
No
32
1
31
0.27
0.27
7/18/2019
7/18/2019
1,2-trans-dichloroethylene
156-60-5
ug/L
100
No
32
0
32
ND
ND
5/2/2019
5/28/2020
1,1,1-trichloroethane
71-55-6
ug/L
2500
No
32
0
32
ND
ND
5/2/2019
5/28/2020
1,1,2-trichloroethane
79-00-5
ug/L
0.55
No
32
0
32
ND
ND
5/2/2019
5/28/2020
Trichloroethylene
79-01-6
ug/L
2.5
No
32
0
32
ND
ND
5/2/2019
5/28/2020
Vinyl chloride 75-01-4
ug/L
0.025
No
32
0
32
ND
ND
5/2/2019
5/28/2020
Organic Toxic Pollutants (GC/MS Fraction - ri*irompounds)
a
Organic Toxic Pollutants (GC/MS Fraction - Base/Neutral
Compound
95-50-1
ug/L
470
4
IMII
0
4
ND
ND
5/27/2020
5/28/2020
1,2-dichlorobenzene
No
1,3-dichlorobenzene
541-73-1
ug/L
390
No
32
0
32
ND
ND
5/2/2019
5/28/2020
1,4-dichlorobenzene
106-46-7
ug/L
488 ug/L - total
chlorinated
benzenes
No
4
0
4
ND
ND
5/27/2020
5/28/2020
1,2,4-trichlorobenzene
120-82-1
ug/L
61
No
4
0
4
ND
ND
5/27/2020
5/28/2020
Organic Toxic Pollutants (GC/MS Fraction - Pesticides)
TABLE E. CERTAIN HAZARDOUS SUBSTANCES AND ASBESTOS (40 CFR 122.21(k)(5)(v))
Allyl chloride
ug/L
NA
No
38
0
28
ND
ND
5/2/2019
8/12/2019
Carbon disulfide
ug/L
100
No
32
4
28
0.64
0.38
5/2/2019
5/2/2019
Cyclohexane
ug/L
230
No
4
0
4
ND
ND
5/27/2020
5/28/2020
Methyl methacrylate
ug/L
9600
No
28
0
28
ND
ND
5/2/2019
8/12/2019
Styrene
ug/L
NA
No
32
0
32
ND
ND
5/2/2019
5/28/2020
Vanadium
mg/L
NA
No
4
4
0
0.01
0.0003
5/27/2020
5/28/2020
Vinyl acetate
ug/L
NA
No
28
0
28
ND
ND
5/2/2019
8/12/2019
TABLE E. 2,3,7,8 TETRACHLORODIBENZO P DIOXIN (2,3 7,8 TCDD) (40 CFR 122.21(g)(7)(viii))
Notes
ND - Not Detected
NR - Not Recorded
NA - No Applicable Standard
mg/L - milligrams per liter
ug/L - microgram per liter
NC 02B Standards
EPA NRWQC
In -Stream Target Values
TR0795A
Page 2 of 28
June 2021

Table 2
Onsite Untreated Seep Data Summary for 2018 to 2020
Chemours Fayetteville Works, North Carolina
Geosyntec Consultants of NC P.C.
Parameter name (as used in data analysis)
CAS Number
Units
Minimum
Regulatory
Critera
Greater Than
Criteria (Y/N)
No. Total
Results
No. Total of
Detects
No. Total Non-
Detects
Maximum
Minimum
Source Data
beginning date
Source Data
end date
TABLE A. CONVENTIONAL AND NON CONVENTIONAL PARAMETER ESTIMATES (40 CFR 122.21(k)(5)(i))
i
Biochemical Oxygen Demand (BOD) - 5 Day
BOD
mg/L
NA
Noj__ 4
0
4
ND
ND
10/23/2020
10/23/2020
Chemical Oxygen Demand (COD)
COD
mg/L
NA
No 4
0
4
ND
ND
10/23/2020
10/23/2020
Total Organic Carbon
TOC
mg/L
NA
No
26
25
1
10.4
1
2/5/2019
10/23/2020
Total Suspended Solids
TSS
mg/L
NA
No
32
32
0
3740
3.1
2/5/2019
10/23/2020
Ammonia
mg L
pH and Temp
Dependent
No
26
12
14
0.13
0.052
2/5/2019
10/23/2020
Ph
STD Units
6
No
4
4
0
6.5
6.5
10/23/2020
10/23/2020
Ph
STD Units
9
No
, 4
4
0
6.5
6.5
10/23/2020
10/23/2020
TABLE B. CERTAIN CONVENTIONAL AND NON- CONVENTIONAL POLLUTANTS (40 CFR 122.21(k)(5)(ii))
or
Bromide
mg/L
NA
No
4
0
4
ND
ND
10/23/2020
10/23/2020
total residual chlorine
mg/L
0.017
r Yes
4
4
0
0.19
0.08
10/22/2020
10/22/2020
Fecal Coliform
colonies
per
100mL
200
No
4
3
1
180
45
10/22/2020
10/22/2020
Fluoride (16984-48-8)
16984-48-8
mg/L
1.8
No
4
0
4
ND
ND
10/23/2020
10/23/2020
Total Kjeldahl Nitrogen
mg/L
NA
No
4
0
4
ND
ND
10/23/2020
10/23/2020
Oil and Grease
mg/L
NA
No
4
0
4
ND
ND
10/22/2020
10/22/2020
Phosphorous (as P), Total (7723-14-0)
7723-14-0
mg/L
NA
No
4
2
2
0.14
0.1
10/23/2020
10/23/2020
Sulfate (as SO4) (14808-79-8)
14808-79-8
mg/L
250
No
26
26
0
34
5.2
2/5/2019
10/23/2020
Sulfide
mg/L
0.00021
Yes I
4
1
3
1.6
1.6
10/23/2020
10/23/2020
Sulfite (as S03) (14265-45-3)
14265-45-3
mg/L
NA
No
4
0
4
ND
ND
10/22/2020
10/22/2020
Aluminum, Total (7429-90-5)
7429-90-5
mg/L
6.5
No
30
30
0
5.23
0.392
2/5/2019
10/23/2020
Barium, Total (7440-39-3)
7440-39-3
mg/L
1
No
4
4
0
0.086
0.059
10/23/2020
10/23/2020
Boron, Total(7440-42-8)
7440-42-8
mg/L
0.15
No
4
1
3
0.012
0.012
10/23/2020
10/23/2020
Iron, Total (7439-89-6)
7439-89-6
mg/L
1
Yes I
30
30
0
21.4
0.227
2/5/2019
10/23/2020
Magnesium, Total (7439-95-4)
7439-95-4
mg/L
NA
No
26
26
0
1.55
0.506
2/5/2019
10/23/2020
Molybdenum, Total (7439-98-7)
7439-98-7
mg/L
0.16
No
4
0
4
ND
ND
10/23/2020
10/23/2020
Manganese, Total (7439-96-5)
7439-96-5
mg/L
0.05
I Yes I
30
30
0
0.434
0.0095
2/5/2019
10/23/2020
Tin, Total (7440-31-5)
7440-31-5
mg/L
0.77
No
4
0
4
ND
ND
10/23/2020
10/23/2020
Titanium, Total (7440-32-6)
Radioactive
Gross Alpha
7440-32-6
mg/L
pCi/L
NA
No
4
4
3
4
1
.
0
0.023
3.67
0.0053
.
2.25
10/23/2020
10/23/2020
10/23/2020
10/23/2020
15
No
Gross Beta
pCi/L
50
No
4
4
0
11.5
5.34
10/23/2020
10/23/2020
Radium (Total)
pCi/L
5
Yes
I
4
4
0
9.32
4.72
10/23/2020
10/23/2020
Radium-226
pCi/L
5
No
4
3
1
2.03
0.701
10/23/2020
10/23/2020
TABLE C. TOXIC METALS, TOTAL CYANIDE, AND TOTAL PHENOLS (40 CFR 122.21(k)(5)(i i)(A))1
Antimony
7440-36-0
mg/L
0.0056
No
7
0
7
ND
ND
2/6/2019
10/23/2020
Arsenic
7440-38-2
mg/L
0.01
No
7
0
7
ND
ND
2/6/2019
10/23/2020
Beryllium
7440-41-7
mg/L
0.0065
No
7
3
4
0.0013
0.001
10/23/2020
10/23/2020
Cadmium
7440-43-9
mg/L
0.00042
No
7
0
7
ND
ND
2/6/2019
10/23/2020
Chromium
7440-47-3
mg/L
0.011
No
7
0
7
ND
ND
2/6/2019
10/23/2020
Copper
7440-50-8
mg/L
0.00896
No
7
0
7
ND
ND
2/6/2019
10/23/2020
Lead
7439-92-1
mg/L
0.00252
No
7
0
7
ND
ND
2/6/2019
10/23/2020
Mercury
7439-97-6
mg/L
0.000012
Yes
7
1
6
0.00008
0.00008
10/23/2020
10/23/2020
Nickel
7440-02-0
mg/L
0.025
No
7
4
3
0.0045
0.0028
2/7/2019
10/23/2020
Selenium
7782 49-2
mg/L
0.005
Yes
11
1
10
0.0248
0.0248
2/6/2019
2/6/2019
TR0795A
Page 3 of 28
June 2021

Table 2
Onsite Untreated Seep Data Summary for 2018 to 2020
Chemours Fayetteville Works, North Carolina
Geosyntec Consultants of NC P.C.
Parameter name (as used in data analysis)
CAS Number
Units
Minimum
Regulatory
Critera
Greater Than
Criteria (Y/N)
No. Total
Results
No. Total of
Detects
No. Total Non-
Detects
Maximum
Minimum
Source Data
beginning date
Source Data
end date
Silver
7440-22-4
mg/L
0.00006
11
0
11
ND
ND
2/6/2019
10/23/2020
Thallium
7440-28-0
mg/L
0.002
No
4
0
4
ND
ND
10/23/2020
10/23/2020
Zinc
7440-66-6
mg/L
0.11718
No
7
6
1
0.0181
0.016
2/7/2019
10/23/2020
Cyanide
57-12-5
mg/L
0.004
I No
4
0
4
ND
ND
10/22/2020
10/22/2020
Total Phenols
mg/L
NA
No
4
0
4
ND
ND
10/22/2020
10/22/2020
TABLE D. ORGANIC TOXIC POLLUTANTS (Gas Chromatography/Mass Spectrometry or GC/MS Fractions) (40 CFR 122.21(k)(5)(iii)(B))
Organic Toxic Pollutants (GC/MS Fraction - Volatile Compounds)
Acrolein
107-02-8
ug/L
3
h No
10
0
10
ND
ND
2/5/2019
10/22/2020
Acrylonitrile
107-13-1
ug/L
0.061
r No
10
0
10
ND
ND
2/5/2019
10/22/2020
Benzene
71-43-2
ug/L
1.19
No
6
0
6
ND
ND
2/5/2019
2/7/2019
Bromoform
75-25-2
ug/L
7
No
6
0
6
ND
ND
2/5/2019
2/7/2019
Carbon Tetrachloride
56-23-5
ug/L
0.254
No
6
0
6
ND
ND
2/5/2019
2/7/2019
Chlorobezene
108-90-7
ug/L
140
No
6
0
6
ND
ND
2/5/2019
2/7/2019
Chlorodibromomethane
124-48-1
ug/L
0.8
No
6
0
6
ND
ND
2/5/2019
2/7/2019
Ethyl Chloride
75-00-3
ug/L
NA
No
6
0
6
ND
ND
2/5/2019
2/7/2019
2-chloroethylvinyl ether
110-75-8
ug/L
NA
No
10
0
10
ND
ND
2/5/2019
10/22/2020
Chloroform
67-66-3
ug/L
60
No
6
0
6
ND
ND
2/5/2019
2/7/2019
Dichlorobromomethane
75-27-4
ug/L
0.55
No
6
0
6
ND
ND
2/5/2019
2/7/2019
1,1-dichloroethane
75-34-3
ug/L
6
No
6
0
6
ND
ND
2/5/2019
2/7/2019
1,2-dichloroethane
107-06-2
ug/L
9.9
No
6
0
6
ND
ND
2/5/2019
2/7/2019
1,1-dichloroethylene
75-35-4
ug/L
300
No
6
0
6
ND
ND
2/5/2019
2/7/2019
1,2-dichloropropane
78-87-5
ug/L
0.9
No
6
0
6
ND
ND
2/5/2019
2/7/2019
Ethylbenzene
100-41-4
ug/L
68
No
6
0
6
ND
ND
2/5/2019
2/7/2019
Methyl bromide
74-83-9
ug/L
0.04
No
6
0
6
ND
ND
2/5/2019
2/7/2019
Methyl chloride
74-87-3
ug/L
2.6
No
6
0
6
ND
ND
2/5/2019
2/7/2019
Methylene chloride
75-09-2
ug/L
20
No
6
0
6
ND
ND
2/5/2019
2/7/2019
1,1,2,2-tetrachloroethane
79-34-5
ug/L
0.17
No
6
0
6
ND
ND
2/5/2019
2/7/2019
Tetrachloroethylene
127-18-4
ug/L
0.7
No
6
0
6
ND
ND
2/5/2019
2/7/2019
Toluene
108-88-3
ug/L
11
No
6
0
6
ND
ND
2/5/2019
2/7/2019
1,2-trans-dichloroethylene
156-60-5
ug/L
100
No
6
0
6
ND
ND
2/5/2019
2/7/2019
1,1,1-trichloroethane
71-55-6
ug/L
2500
No
6
0
6
ND
ND
2/5/2019
2/7/2019
1,1,2-trichloroethane
79-00-5
ug/L
0.55
No
6
0
6
ND
ND
2/5/2019
2/7/2019
Trichloroethylene
79-01-6
ug/L
2.5
No
6
0
6
ND
ND
2/5/2019
2/7/2019
Vinyl chloride
75-01-4
ug/L
0.025
No
6
0
6
ND
ND
2/5/2019
2/7/2019
Organic Toxic Pollutants (GC/MS Fraction - Acid Compounds)
2-chlorophenol
95-57-8
ug/L
1 ug/L - total
chlorinated
phenols
No
10
0
10
ND
ND
2/5/2019
10/23/2020
2,4-dichlorophenol
120-83-2
ug/L
big/L - total
lorinatedheol
phenols
No
10
0
10
ND
ND
2/5/2019
10/23/2020
2,4-dimethylphenol
105-67-9
ug/L
100
No
10
0
10
ND
ND
2/5/2019
10/23/2020
4,6-dinitro-o-cresol
534-52-1
ug/L
NA
No
10
0
10
ND
ND
2/5/2019
10/23/2020
2,4-dinitrophenol
51-28-5
ug/L
10
No
10
0
10
ND
ND
2/5/2019
10/23/2020
2-nitrophenol
88-75-5
ug/L
NA
No
10
0
10
ND
ND
2/5/2019
10/23/2020
4-nitrophenol
100-02-7
ug/L
NA
No
10
0
10
ND
ND
2/5/2019
10/23/2020
TR0795A
Page 4 of 28
June 2021

Table 2
Onsite Untreated Seep Data Summary for 2018 to 2020
Chemours Fayetteville Works, North Carolina
Geosyntec Consultants of NC P.C.
Parameter name (as used in data analysis)
CAS Number
Units
Minimum
Regulatory
Critera
Greater Than
Criteria (Y/N)
No. Total
Results
No. Total of
Detects
No. Total Non-
Detects
Maximum
Minimum
Source Data
beginning date
Source Data
end date
p-chloro-m-cresol
59-50-7
ug/L
ug/L - to .
, lorinated
phenols
No
10
0
10
ND
ND
2/5/2019
10/23/2020
Pentachlorophenol
87-86-5
ug/L
1 ug/L - total
lorinated
phenols
No
10
0
10
ND
ND
2/5/2019
10/23/2020
Phenols
108-95-2
ug/L
4000
No
10
0
10
ND
ND
2/5/2019
10/23/2020
2,4,6-trichlorophenol
88-06-2
g/L - total
ug/L lorinated
phenols
No
10
0
10
ND
ND
2/5/2019
10/23/2020
Organic pollutants (GC/MS Fraction - Base/Na
Acenapthene
83-32-9
ug/L
60
10
0
10
ND
ND
2/5/2019
10/23/2020
No
Acenapthylene
208-96-8
ug/L
NA
No 10
0
10
ND
ND
2/5/2019
10/23/2020
Anthracene
120-12-7
ug/L
0.05
No 10
0
10
ND
ND
2/5/2019
10/23/2020
Benzidine
92-87-5
ug/L
0.00014
No 10
0
10
ND
ND
2/5/2019
10/23/2020
Benzo (a) anthracene
56-55-3
ug/L
0.1
No 10
0
10
ND
ND
2/5/2019
10/23/2020
Benzo (a) pyrene
50-32-8
ug/L
0.05
No 10
0
10
ND
ND
2/5/2019
10/23/2020
3,4-benzofluoranthene
205-99-2
ug/L
'8 Pstotal
No
10
0
10
ND
ND
2/5/2019
10/23/2020
Benzo (ghi) perylene
191-24-2
ug/L
NA
No
10
0
10
ND
ND
2/5/2019
10/23/2020
Benzo (k) fluoranthene
207-08-9
ug/L
r.8 nPg/ALH-stotal
No
10
0
10
ND
ND
2/5/2019
10/23/2020
Bis(2-chloroethoxy) methane
111-91-1
ug/L
100
No
10
0
10
ND
ND
2/5/2019
10/23/2020
Bis (2-chloroethyl) ether
111-44-4
ug/L
0.03
No
10
0
10
ND
ND
2/5/2019
10/23/2020
Bis (2-chloroisopropyl) ether
39638-32-9
ug/L
NA
No
6
0
6
ND
ND
2/5/2019
2/7/2019
Bis (2-ethylhexyl) phthalate
117-81-7
ug/L
0.32
I No
10
0
10
ND
ND
2/5/2019
10/23/2020
4-bromophenyl phenyl ether
101-55-3
ug/L
2
No
10
0
10
ND
ND
2/5/2019
10/23/2020
Butyl benzyl phthalate
85-68-7
ug/L
0.1
No
10
0
10
ND
ND
2/5/2019
10/23/2020
2-chloronaphthalene
91-58-7
ug/L
110
No
10
0
10
ND
ND
2/5/2019
10/23/2020
4-chlorophenylphenylether
7005-72-3
ug/L
NA
No
10
0
10
ND
ND
2/5/2019
10/23/2020
Chrysene
218-01-9
ug/L
2.8 PAHL stotal
No
10
0
10
ND
ND
2/5/2019
10/23/2020
Dibenzo (a,h) anthracene
53-70-3
ug/L
5
I No
10
0
10
ND
ND
2/5/2019
10/23/2020
1,2-dichlorobenzene
95-50-1
ug/L
488 ug/L - total
chlorinated
benzenes
No
10
0
10
ND
ND
2/5/2019
10/23/2020
1,3-dichlorobenzene
541-73-1
ug/L
488 ug/L - total
lorinated
enzenes
No i
10
0
10
ND
ND
2/5/2019
10/23/2020
106 46-7
ug/L
488 ug/L - totalIII1,4-dichlorobenzene
lorinated
enzenes
No
10
0
10
ND
ND
2/5/2019
10/23/2020
3,3-dichlorobenzidine
91-94-1
ug/L
0.049
No
10
0
10
ND
ND
2/5/2019
10/23/2020
Diethyl phthalate
84-66-2
ug/L
600
No
10
0
10
ND
ND
2/5/2019
10/23/2020
Dimethyl phthalate
131-11-3
ug/L
2000
No
10
0
10
ND
ND
2/5/2019
10/23/2020
Di-n-butyl phthalate
84-74-2
ug/L
9.5
No
10
4
6
3.5
2.5
10/23/2020
10/23/2020
2,4-dinitrotoluene
121-14-2
ug/L
0.049
s No
10
0
10
ND
ND
2/5/2019
10/23/2020
TR0795A
Page 5 of 28
June 2021

Table 2
Onsite Untreated Seep Data Summary for 2018 to 2020
Chemours Fayetteville Works, North Carolina
Geosyntec Consultants of NC P.C.
Parameter name (as used in data analysis)
CAS Number
Units
Minimum
Regulatory
Critera
Greater Than
Criteria (Y/N)
No. Total
Results
No. Total of
Detects
No. Total Non-
Detects
Maximum
Minimum
Source Data
beginning date
Source Data
end date
2,6-dinitrotoluene
606-20-2
ug/L
0.048
10
0
10
ND
ND
2/5/2019
10/23/2020
Di-n-octylphthalate
117-84-0
ug/L
NA
No
10
0
10
ND
ND
2/5/2019
10/23/2020
1,2-diphenylhydrazine
122-66-7
ug/L
0.03
No
10
0
10
ND
ND
2/5/2019
10/23/2020
Fluoranthene
206-44-0
ug/L
0.11
No
10
0
10
ND
ND
2/5/2019
10/23/2020
Fluorene
86-73-7
ug/L
30
No
10
0
10
ND
ND
2/5/2019
10/23/2020
Hexachlorobenzene
118-74-1
ug/L
488 ug/L - total
chlorinated
benzenes
No
10
0
10
ND
ND
2/5/2019
10/23/2020
Hexachlorobutadiene
87-68-3
ug/L
0.44
No
10
0
10
ND
ND
2/5/2019
10/23/2020
Hexachlorocyclopentadiene
77-47-4
ug/L
0.07
No
10
0
10
ND
ND
2/5/2019
10/23/2020
Hexachloroethane
67-72-1
ug/L
0.1
No
10
0
10
ND
ND
2/5/2019
10/23/2020
Indeno (1,2,3-cd) pyrene
193-39-5
ug/L
Ilit P/AL -stotal
No
10
0
10
ND
ND
2/5/2019
10/23/2020
Isophorone
78-59-1
ug/L
34
No
10
0
10
ND
ND
2/5/2019
10/23/2020
Napthalene
91-20-3
ug/L
12
No I
10
0
10
ND
ND
2/5/2019
10/23/2020
Nitrobenzene
98-95-3
ug/L
10
No
10
0
10
ND
ND
2/5/2019
10/23/2020
N-nitrosodimethylamine
62-75-9
ug/L
17000
No
10
0
10
ND
ND
2/5/2019
10/23/2020
N-nitrosodi-n-propylamine
621-64-7
ug/L
0.005
No I
10
0
10
ND
ND
2/5/2019
10/23/2020
N-nitrosodiphenylamine
86-30-6
ug/L
0.00069
No
10
0
10
ND
ND
2/5/2019
10/23/2020
Phenanthrene
85-01-8
ug/L
0.7
No
10
0
10
ND
ND
2/5/2019
10/23/2020
Pyrene
129-00-0
ug/L
20
No
10
0
10
ND
ND
2/5/2019
10/23/2020
1,2,4-trichlorobenzene
120-82-1
ug/L
61
No
10
0
10
ND
ND
2/5/2019
10/23/2020
Organic Toxic Pollutants (GC/MS Fraction - Pesticides)
MI
Aldrin
309-00-2
ug/L
0.00005
No
4
0
4
ND
ND
10/23/2020
10/23/2020
a-BHC
319-84-6
ug/L
0.00036
No
4
0
4
ND
ND
10/23/2020
10/23/2020
3-BHC
319-85-7
ug/L
0.008
No
4
0
4
ND
ND
10/23/2020
10/23/2020
y-BHC
58-89-9
ug/L
0.01
No
4
0
4
ND
ND
10/23/2020
10/23/2020
S-BHC
319-86-8
ug/L
40
No
4
0
4
ND
ND
10/23/2020
10/23/2020
Chlordane
57-74-9
ug/L
0.0008
No
4
0
4
ND
ND
10/23/2020
10/23/2020
4,4-DDT
50-29-3
ug/L
0.0002
No
4
0
4
ND
ND
10/23/2020
10/23/2020
4,4-DDE
72-55-9
ug/L
0.000018
No
4
0
4
ND
ND
10/23/2020
10/23/2020
4,4-DDD
72-54-8
ug/L
0.00012
No
4
0
4
ND
ND
10/23/2020
10/23/2020
Dieldrin
60-57-1
ug/L
0.00005
No
4
0
4
ND
ND
10/23/2020
10/23/2020
a-endosulfan
959-98-8
ug/L
20
No I
4
0
4
ND
ND
10/23/2020
10/23/2020
(3-endosulfan
33213-65-9
ug/L
0.05
No
4
0
4
ND
ND
10/23/2020
10/23/2020
Endosulfan sulfate
1031-07-8
ug/L
0.05
No
4
0
4
ND
ND
10/23/2020
10/23/2020
Endrin
72-20-8
ug/L
0.002
No I
4
0
4
ND
ND
10/23/2020
10/23/2020
Endrin aldehyde
7421-93-4
ug/L
1
No
4
0
4
ND
ND
10/23/2020
10/23/2020
Heptachlor
76-44-8
ug/L
0.00008
No
4
0
4
ND
ND
10/23/2020
10/23/2020
Heptachlor epoxide
1024-57-3
ug/L
0.000032
No
4
0
4
ND
ND
10/23/2020
10/23/2020
53469-21-9
ug/L
1 ug/L - total
pusPCB-1242
PCBs
No
4
0
4
ND
ND
10/23/2020
10/23/2020
PCB-1254
11097-69-1
ug/L
0.001 ug/L -total
PCBs
No
4
0
4
ND
ND
10/23/2020
10/23/2020
PCB-1221
11104-28-2
ug/L
0.001 ug/L -total
PCBs
No
4
0
4
ND
ND
10/23/2020
10/23/2020
TR0795A
Page 6 of 28
June 2021

Table 2
Onsite Untreated Seep Data Summary for 2018 to 2020
Chemours Fayetteville Works, North Carolina
Geosyntec Consultants of NC P.C.
Parameter name (as used in data analysis)
CAS Number
Units
Minimum
Regulatory
Critera
Greater Than
Criteria (Y/N)
No. Total
Results
No. Total of
Detects
No. Total Non-
Detects
Maximum
Minimum
Source Data
beginning date
Source Data
end date
PCB-1232
11141-16-5
ug/L
0.001 ug/L
PCBs
4
0
4
ND
ND
10/23/2020
10/23/2020
PCB-1248
12672-29-6
ug/L
0.001 ug/L -total
PCBs
No
4
0
4
ND
ND
10/23/2020
10/23/2020
PCB-1260
11096-82-5
ug/L
0.001 ug/L -total
PCBs
No
4
0
4
ND
ND
10/23/2020
10/23/2020
PCB-1016
12674-11-2
ug/L
0.001 ug/L -total
PCBs
No
4
0
4
ND
ND
10/23/2020
10/23/2020
Toxaphene
8001-35-2
ug/L
0.0002 I
No
4 0
4
ND
ND
10/23/2020
10/23/2020
TABLE E. CERTAIN HAZARDOUS SUBSTANCES AND ASBESTOS (40 CFR 122.21(k)(5)(v)) IIIIII
TABLE E. 2,3,7,8 TETRACHLORODIBENZO P DIOXIN (2,3,7,8 TCDD) (40 CFR 122.21(g)(7)(viii))
2,3,7,8-TCDD pg/L 0.000005 L 4 0
4
ND
ND 10/23/2020
10/23/2020
Notes
ND - Not Detected
NR - Not Recorded
NA - No Applicable Standard
mg/L - milligrams per liter
ug/L - microgram per liter
pCi/L - picocuries per liter
pg/L - picogram per liter
NC 02B Standards
EPA NRWQC
In -Stream Target Values
No Exceedance
NC 02B Standards are for total compounds
TR0795A Page 7 of 28 June 2021

Table 3 Geosyntec Consultants of NC P.C.
Flows used for the Water Quality Assessment
Chemours Fayetteville Works, North Carolina
Source'
Flow (MGD)
EW-1
0.703
EW-3
0.449
PIW-10S
0.091
PIW-5S
0.125
SEEP -A -WALL
0.155
SEEP-B-WALL
0.233
Total
1.756
Outfall 002
18.025
Notes
MGD - million gallons per day
' Flows for the groundwater and seeps represent
maximum daily estimates.
2 Outfall 002 is the average annual daily flow
estimate.
TR0795A Page 8 June 2021

Table 4
Results for Single Samples of Untreated Groundwater and Seeps from March 3, 2021
Chemours Fayetteville Works, North Carolina
Geosyntec Consultants of NC P.C.
Grouping/Parameter
Units
EW-1
EW-3
PIW-10S
PIW-5S
SEEP -A-
WALL
SEEP-B-
WALL
Estimated
Load (lb/d)
Estimated
FWMCa
Table A. Conventional and Non -Conventional Parameters
Ill
i
Ammonia
mg/L
<0.05
<0.05
<0.05
<0.05
<0.05
<0.05
< 0.73
< 0.05
Biochemical Oxygen Demand (BOD) - 5 Day
MG/L
<1.5
<1.5
<1.5
<1.5
<1.5
<1.5
< 22
< 1.5
Chemical Oxygen Demand (COD)
MG/L
<25
<25
<25
<25
27
<25
< 369
< 25
Table B. Certain Conventional and Non -Conventional Parameters
Aluminum
MG/L
0.035
0.41
1.2
0.96
14
0.65
23
1.57
Barium
MG/L
0.056
0.05
0.036
0.038
0.04
0.021
0.68
0.046
Magnesium
MG/L
1.3
5.4
0.61
0.84
1.2
0.69
32
2.19
Molybdenum
MG/L
<0.00013
<0.00013
<0.00013
<0.00013
0.00043
<0.00013
< 0.0023
< 0.00016
Oil and Grease
MG/L
<1.5
<1.5
<1.6
<1.6
<1.5
<1.6
< 22
< 1.5
Tin
MG/L
<0.0006
<0.0006
<0.0006
<0.0006
<0.0006
<0.0006
< 0.009
< 0.0006
Titanium
MG/L
<0.006
<0.006
0.017
<0.006
0.55
0.012
< 0.810
< 0.055
total residual chlorine
MG/L
0.21
0.14
<0.01
0.12
<0.01
0.19
< 2.3
< 0.16
Hazardous Parameter
1.1
2,3,7,8-TCDD
PG/L
<0.073
<0.093
<0.084
<0.12
<0.091
<0.037
< 1.16E-09
< 0.079
Metals
Antimony
MG/L
<0.00041
<0.00041
<0.00041
<0.00041
<0.00041
<0.00041
< 0.006
< 0.00041
Arsenic
MG/L
<0.00068
<0.00068
0.002
<0.00068
0.0013
<0.00068
< 0.012
< 0.00080
Chromium
MG/L
<0.00033
0.00035
0.0011
<0.00033
0.012
0.00047
< 0.021
< 0.0014
Nickel
MG/L
0.0011
<0.0006
0.0025
0.0046
0.0047
0.0018
< 0.025
< 0.0017
Total Phenols
MG/L
<0.01
<0.01
<0.01
<0.01
<0.01
<0.01
< 0.147
< 0.01
Zinc
MG/L
0.017
0.09
<0.0062
0.009
0.021
<0.0062
< 0.491
< 0.033
Organic Toxic Pollutants (GC/MS Fraction - Acid Compounds)
'
r
2,4,6-Trichlorophenol
UG/L
<0.2
<0.22
<2.3
<0.21
<0.21
<0.22
< 0.005
< 0.32
2,4-Dichlorophenol
UG/L
<0.1
<0.11
<1.1
<0.1
<0.1
<0.11
< 0.002
< 0.16
2,4-Dimethylphenol
UG/L
<0.2
<0.22
<2.3
<0.21
<0.21
<0.22
< 0.005
< 0.32
2,4-Dinitrophenol
UG/L
<1
<1.1
<11
<1
<1
<1.1
< 0.023
< 1.6
2-Chlorophenol
UG/L
<0.2
<0.22
<2.3
<0.21
<0.21
<0.22
< 0.005
< 0.32
TR0795A
Page 9 of 28
June 2021

Table 4
Results for Single Samples of Untreated Groundwater and Seeps from March 3, 2021
Chemours Fayetteville Works, North Carolina
Geosyntec Consultants of NC P.C.
Grouping/Parameter
Units
EW-1
EW-3
PIW-10S
PIW-5S
SEEP -A-
WALL
SEEP-B-
WALL
Estimated
Load (lb/d)
Estimated
FWMCa
2-Nitrophenol
UG/L
<0.31
<0.32
<3.4
<0.31
<0.31
<0.33
< 0.007
< 0.47
4,6-Dinitro-2-Methylphenol
UG/L
<1
<1.1
<11
<1
<1
<1.1
< 0.023
< 1.6
4-Chloro-3-Methylphenol
UG/L
<0.31
<0.32
<3.4
<0.31
<0.31
<0.33
< 0.007
< 0.47
Pentachlorophenol
UG/L
<0.82
<0.86
<9.1
<0.83
<0.83
<0.88
< 0.019
< 1.27
Phenol
UG/L
<0.41
<0.43
<4.6
<0.42
<0.41
<0.44
< 0.009
< 0.64
Organic Toxic Pollutants (GC/MS Fraction - Base/Neutral Compounds)
1,2,4-Trichlorobenzene
UG/L
<0.2
<0.22
<2.3
<0.21
<0.21
<0.22
< 0.005
< 0.32
2,4-Dinitrotoluene
UG/L
<0.1
<0.11
<1.1
<0.1
<0.1
<0.11
< 0.002
< 0.16
2,6-Dinitrotoluene
UG/L
<0.2
<0.22
<2.3
<0.21
<0.21
<0.22
< 0.005
< 0.32
2-Chloronaphthalene
UG/L
<0.61
<0.65
<6.8
<0.62
<0.62
<0.66
< 0.014
< 0.95
3,3'-Dichlorobenzidine
UG/L
<0.31
<0.32
<3.4
<0.31
<0.31
<0.33
< 0.007
< 0.47
4-Bromophenyl Phenyl Ether
UG/L
<0.2
<0.22
<2.3
<0.21
<0.21
<0.22
< 0.005
< 0.32
4-Chlorophenyl Phenyl Ether
UG/L
<0.2
<0.22
<2.3
<0.21
<0.21
<0.22
< 0.005
< 0.32
Acenaphthene
UG/L
<0.092
<0.097
<1
4
<0.093
<0.099
< 0.006
< 0.42
Acenaphthylene
UG/L
<0.082
<0.086
<0.91
<0.083
<0.083
<0.088
< 0.002
< 0.13
Anthracene
UG/L
<0.071
<0.075
<0.8
1.2
<0.073
<0.077
< 0.003
< 0.19
Benzo(A)Anthracene
UG/L
<0.2
<0.22
<2.3
1
<0.21
<0.22
< 0.005
< 0.37
Benzo(A)Pyrene
UG/L
<0.2
<0.22
<2.3
0.24
<0.21
<0.22
< 0.005
< 0.32
Benzo(B)Fluoranthene
UG/L
<0.2
<0.22
<2.3
0.36
<0.21
<0.22
< 0.005
< 0.33
Benzo(G,H,I)Perylene
UG/L
<0.1
<0.11
<1.1
<0.1
<0.1
<0.11
< 0.002
< 0.16
Benzo(K)Fluoranthene
UG/L
<0.1
<0.11
<1.1
0.2
<0.1
<0.11
< 0.002
< 0.16
Bis(2-Chloroethoxy)Methane
UG/L
<0.2
<0.22
<2.3
<0.21
<0.21
<0.22
< 0.005
< 0.32
Bis(2-Chloroethyl)Ether
UG/L
<0.1
<0.11
<1.1
<0.1
<0.1
<0.11
< 0.002
< 0.16
Bis(2-Ethylhexyl)Phthalate
UG/L
<1
<1.1
<11
<1
<1
<1.1
< 0.023
< 1.56
Butyl Benzyl Phthalate
UG/L
<1
<1.1
<11
<1
<1
<1.1
< 0.023
< 1.56
Chrysene
UG/L
<0.2
<0.22
<2.3
0.84
<0.21
<0.22
< 0.005
< 0.36
Dibenz(A,H)Anthracene
UG/L
<0.1
<0.11
<1.1
<0.1
<0.1
<0.11
< 0.002
< 0.16
Diethyl Phthalate
UG/L
<0.31
<0.32
<3.4
<0.31
<0.31
<0.33
< 0.007
< 0.47
TR0795A
Page 10 of 28
June 2021

Table 4
Results for Single Samples of Untreated Groundwater and Seeps from March 3, 2021
Chemours Fayetteville Works, North Carolina
Geosyntec Consultants of NC P.C.
Grouping/Parameter
Units
EW-1
EW-3
PIW-10S
PIW-5S
SEEP -A-
WALL
SEEP-B-
WALL
Estimated
Load (lb/d)
Estimated
FWMCe
Dimethyl Phthalate
UG/L
<0.51
<0.54
<5.7
<0.52
<0.52
<0.55
< 0.012
< 0.79
Di-N-Butyl Phthalate
UG/L
<1
<1.1
<11
<1
<1
<1.1
< 0.023
< 1.56
Fluoranthene
UG/L
<0.2
<0.22
<2.3
6.4
<0.21
<0.22
< 0.011
< 0.76
Fluorene
UG/L
<0.2
<0.22
<2.3
5.4
<0.21
<0.22
< 0.010
< 0.69
Hexachlorobenzene
UG/L
<0.51
<0.54
<5.7
<0.52
<0.52
<0.55
< 0.012
< 0.79
Hexachlorobutadiene
UG/L
<0.2
<0.22
<2.3
<0.21
<0.21
<0.22
< 0.005
< 0.32
Hexachlorocyclopentadiene
UG/L
<0.2
<0.22
<2.3
<0.21
<0.21
<0.22
< 0.005
< 0.32
Hexachloroethane
UG/L
<0.1
<0.11
<1.1
<0.1
<0.1
<0.11
< 0.002
< 0.16
Indeno(1,2,3-CD)Pyrene
UG/L
<0.2
<0.22
<2.3
<0.21
<0.21
<0.22
< 0.005
< 0.32
Isophorone
UG/L
<0.2
<0.22
<2.3
<0.21
<0.21
<0.22
< 0.005
< 0.32
Naphthalene
UG/L
<0.1
<0.11
<1.1
7.4
<0.1
<0.11
< 0.010
< 0.68
N-Dioctyl Phthalate
UG/L
<0.51
<0.54
<5.7
<0.52
<0.52
<0.55
< 0.012
< 0.79
Nitrobenzene
UG/L
<0.2
<0.22
<2.3
<0.21
<0.21
<0.22
< 0.005
< 0.32
N-Nitrosodi-N-Propylamine
UG/L
<0.2
<0.22
<2.3
<0.21
<0.21
<0.22
< 0.005
< 0.32
N-Nitrosodiphenylamine
UG/L
<0.1
<0.11
<1.1
<0.1
<0.1
<0.11
< 0.002
< 0.16
Phenanthrene
UG/L
<0.1
<0.11
<1.1
16
<0.1
<0.11
< 0.019
< 1.29
Pyrene
UG/L
<0.2
<0.22
<2.3
3.5
<0.21
<0.22
< 0.008
< 0.55
Organic Toxic Pollutants (GC/MS Fraction - Pesticides)
4,4'-DDD
UG/L
<0.0096
<0.0095
<0.01
<0.0095
<0.0093
<0.0093
< 0.0001
< 0.010
4,4'-DDE
UG/L
<0.021
<0.021
<0.023
<0.021
<0.021
<0.021
< 0.0003
< 0.021
4,4'-DDT
UG/L
<0.011
<0.011
<0.011
<0.011
<0.01
<0.01
< 0.0002
< 0.011
Aldrin
UG/L
<0.0053
<0.0053
<0.0056
<0.0053
<0.0051
<0.0052
< 0.0001
< 0.005
Alpha-BHC
UG/L
<0.013
<0.013
<0.014
<0.013
<0.012
<0.012
< 0.0002
< 0.013
beta-BHC
UG/L
<0.049
<0.049
<0.052
<0.048
<0.047
<0.048
< 0.001
< 0.049
Chlordane
UG/L
<0.25
<0.25
<0.26
<0.24
<0.24
<0.24
< 0.004
< 0.248
delta-BHC
UG/L
<0.012
<0.012
<0.012
<0.012
<0.011
<0.011
< 0.0002
< 0.012
Dieldrin
UG/L
<0.0085
<0.0085
<0.009
<0.0084
<0.0082
<0.0083
< 0.0001
< 0.008
Endosulfan I
UG/L
<0.0032
<0.0032
<0.0034
<0.0032
0.037
<0.0031
< 0.0001
< 0.006
TR0795A
Page 11 of 28
June 2021

Table 4
Results for Single Samples of Untreated Groundwater and Seeps from March 3, 2021
Chemours Fayetteville Works, North Carolina
Geosyntec Consultants of NC P.C.
Grouping/Parameter
Units
EW-1
EW-3
PIW-10S
PIW-5S
SEEP -A-
WALL
SEEP-B-
WALL
Estimated
Load (lb/d)
Estimated
FWMCa
Endosulfan II
UG/L
<0.01
<0.01
<0.011
<0.01
<0.01
<0.01
< 0.0001
< 0.010
Endosulfan Sulfate
UG/L
<0.011
<0.011
<0.011
<0.011
<0.01
<0.01
< 0.0002
< 0.011
Endrin
UG/L
<0.0096
<0.0095
<0.01
<0.0095
<0.0093
<0.0093
< 0.0001
< 0.010
Endrin Aldehyde
UG/L
<0.0097
<0.0096
<0.01
<0.0096
<0.0094
<0.0094
< 0.0001
< 0.010
Heptachlor
UG/L
<0.0085
<0.0085
<0.009
<0.0084
<0.0082
<0.0083
< 0.0001
< 0.008
Heptachlor Epoxide
UG/L
<0.0053
<0.0053
<0.0056
0.0094
0.018
<0.0052
< 0.0001
< 0.007
PCB 1016
UG/L
<0.079
<0.078
<0.083
<0.078
<0.076
<0.077
< 0.001
< 0.078
PCB 1221
UG/L
<0.079
<0.078
<0.083
<0.078
<0.076
<0.077
< 0.001
< 0.078
PCB 1232
UG/L
<0.079
<0.078
<0.083
<0.078
<0.076
<0.077
< 0.001
< 0.078
PCB 1242
UG/L
<0.079
<0.078
<0.083
<0.078
<0.076
<0.077
< 0.001
< 0.078
PCB 1248
UG/L
<0.079
<0.078
<0.083
<0.078
<0.076
<0.077
< 0.001
< 0.078
PCB 1254
UG/L
<0.079
<0.078
<0.083
<0.078
<0.076
<0.077
< 0.001
< 0.078
PCB 1260
UG/L
<0.079
<0.078
<0.083
<0.078
<0.076
<0.077
< 0.001
< 0.078
Toxaphene
UG/L
<0.38
<0.38
<0.4
<0.37
<0.37
<0.37
< 0.006
< 0.38
Other Parameters
Alpha Chlordane
UG/L
<0.0064
<0.0064
<0.0068
<0.0063
0.036
<0.0062
< 0.000
< 0.01
Bis(2-Chloro-l-Methylethyl) Ether
UG/L
<0.31
<0.32
<3.4
<0.31
<0.31
<0.33
< 0.007
< 0.47
Calcium
MG/L
2.7
9.3
0.46
2
6.4
0.86
63
4.3
Lindane
UG/L
<0.0055
<0.0055
<0.0059
<0.0055
<0.0053
<0.0054
< 0.000
< 0.01
Total Kjeldahl Nitrogen
MG/L
<0.5
<0.5
<0.5
<0.5
<0.5
<0.5
< 7
< 0.5
Notes
a FWMC - flow -weighted mean concentration
lb/d - pounds per day
TR0795A
Page 12 of 28
June 2021

Table 5 Geosyntec Consultants of NC P.C.
Results for Multiple Samples of Untreated Groundwater and Seeps from March/April 2021
Chemours Fayetteville Works, North Carolina
Grouping/Parameter
Date in
2021
Units
EW-1
EW-3
PIW-10S
PIW-5S
SEEP -A -
WALL
SEEP-B-
WALL
Estimated
Load (lb/d)
Estimated
FWMC
Table A. Conventional and Non -Conventional Parameters
Ph
Total Organic Carbon
3-Mar
28-Apr
3-Mar
8-Mar
10-Mar
12-Mar
15-Mar
17-Mar
19-Mar
22-Mar
24-Mar
26-Mar
28-Apr
3-Mar
28-Apr
SU
SU
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
6.8
7
<0.5
<0.5
<0.5
<0.5
<0.5
<0.5
<0.5
<0.5
<0.5
<0.5
<0.5
7.5
5.9
6.5
7
<0.5
<0.5
0.5
<0.5
<0.5
<0.5
<0.5
<0.5
0.93
<0.5
0.76
3.3
20
6.5
7
0.78
0.73
0.91
<0.5
<0.5
0.68
0.67
0.9
0.9
<0.5
1
6
3.9
6.5
7
0.96
0.88
1.1
<0.5
0.52
0.91
0.87
1
1.1
0.59
1.1
2
2.9
6.8
7
4.3
3
3.4
1.6
0.58
4.3
3.6
2
4.2
0.96
1.4
89
4.7
6.5
7
4.5
3.2
3.7
2.6
2.7
4.2
4.5
4.1
5.3
3.8
5.5
23
11
Total Organic Carbon
< 20.71
< 16.38
< 18.23
< 12.83
< 11.73
< 20.00
< 19.63
< 17.09
< 23.99
< 14.44
< 20.20
222.60
143.07
43.15
< 1.41
< 1.12
< 1.24
< 0.9
< 0.80
< 1.36
< 1.34
< 1.2
< 1.6
< 0.99
< 1.4
15.2
9.8
2.94
Table B. Certain Conventional and Non -Conventional Parameters
Boron
Bromide
Cobalt
COLOR TRUE
Fluoride
Iron
3-Mar
28-Apr
mg/L
mg/L
0.012
<0.012
<0.012
<0.012
<0.012
<0.012
<0.012
<0.012
0.014
<0.012
<0.012
<0.012
Boron
3-Mar
8-Mar
10-Mar
12-Mar
15-Mar
17-Mar
19-Mar
22-Mar
24-Mar
26-Mar
28-Apr
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
<1.3
<1.3
<1.3
<1.3
<1.3
<1.3
<1.3
<1.3
<1.3
<1.3
<1.3
<1.3
<1.3
<1.3
<1.3
<1.3
<1.3
<1.3
<1.3
<1.3
<1.3
<1.3
<1.3
<1.3
<1.3
<1.3
<1.3
<1.3
<1.3
<1.3
<1.3
<1.3
<1.3
<1.3
<1.3
<1.3
<1.3
<1.3
<1.3
<1.3
<1.3
<1.3
<1.3
<1.3
<1.3
<1.3
<1.3
<1.3
<1.3
<1.3
<1.3
<1.3
<1.3
<1.3
<1.3
<1.3
<1.3
<1.3
<1.3
<1.3
<1.3
<1.3
<1.3
<1.3
<1.3
<1.3
3-Mar
8-Mar
10-Mar
12-Mar
15-Mar
17-Mar
19-Mar
22-Mar
24-Mar
26-Mar
28-Apr
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
<0.00016
<0.00016
<0.00016
<0.00016
<0.00016
<0.00016
<0.00016
<0.00016
<0.00016
<0.00016
<0.00016
<0.00016
<0.00016
<0.00016
<0.00016
<0.00016
<0.00016
<0.00016
<0.00016
0.0002
<0.00016
0.00017
0.0027
0.0027
0.003
0.0027
0.0029
0.0026
0.0027
0.0026
0.0027
0.0027
0.0028
0.0037
0.0035
0.0038
0.0034
0.0038
0.0035
0.0035
0.0034
0.0045
0.0035
0.0031
0.0016
0.0007
0.00073
0.001
0.0029
0.001
0.001
0.0025
0.00074
0.0027
0.002
0.0017
0.0018
0.0018
0.0018
0.0019
0.0017
0.0018
0.0017
0.0018
0.002
0.002
Cobalt
3-Mar
28-Apr
PCU
PCU
<5
<5
<5
<5
30
<5
<5
<5
60
<5
35
30
3-Mar
mg/L
<0.25
0.32
<0.25
<0.25
0.41 <0.25
28-Apr mg/L <0.25 <0.25 <0.25 <0.25 <0.25
<0.25
3-Mar
8-Mar
10-Mar
12-Mar
15-Mar
mg/L
mg/L
mg/L
mg/L
mg/L
2.1
1.6
1.6
1.6
1.7
10
10
9.9
11
12
2.6
0.45
0.16
0.15
0.061
0.31
0.18
0.098
0.18
1
5.2
0.96
0.69
0.69
0.45
Fluoride
0.71
0.57
0.63
0.63
0.73
< 0.18
< 0.18
0.18
< 0.01
< 0.01
< 0.01
< 0.01
< 0.02
< 0.01
< 0.01
< 0.01
< 0.01
< 0.01
< 0.01
0.01
< 4.13
< 3.66
3.90
60.21
49.77
48.85
53.06
58.07
< 0.012
< 0.012
0.012
< 0.00088
< 0.00079
< 0.00083
< 0.00081
< 0.00103
< 0.00080
< 0.00082
< 0.00093
< 0.00088
< 0.00100
< 0.00092
0.00088
< 0.28
< 0.25
0.27
4.1
3.40
3.33
3.62
3.96
TR0795A
Page 13 of 28
June 2021

Table 5 Geosyntec Consultants of NC P.C.
Results for Multiple Samples of Untreated Groundwater and Seeps from March/April 2021
Chemours Fayetteville Works, North Carolina
Grouping/Parameter
Date in
2021
Units
EW-1
EW-3
PIW-10S
PIW-5S
SEEP -A-
WALL
SEEP-B-
WALL
Estimated
Load (lb/d)
Estimated
FWMC
17-Mar
mg/L
2.1
10
0.32
0.62
1.3
0.74
53.83
3.67
19-Mar
mg/L
2.1
12
0.16
0.4
1.1
0.84
60.92
4.16
22-Mar
mg/L
1.6
14
<0.023
0.091
0.43
0.66
< 63.84
< 4.36
24-Mar
mg/L
1.9
5.1
0.037
12
1.8
0.77
46.67
3.18
26-Mar
mg/L
1.6
11
0.12
1.2
0.42
0.93
54.34
3.71
28-Apr
mg/L
1.6
6.9
0.32
0.35
0.57
1.3
< 39.14
< 2.67
Iron
53.52
3.65
Manganese
3-Mar
mg/L
0.026
0.19
0.012
0.023
0.068
0.018
1.02
0.070
8-Mar
mg/L
0.019
0.19
0.011
0.021
0.026
0.018
0.92
0.063
10-Mar
mg/L
0.019
0.19
0.011
0.02
0.025
0.017
0.92
0.063
12-Mar
mg/L
0.019
0.21
0.012
0.024
0.025
0.017
1.00
0.068
15-Mar
mg/L
0.021
0.21
0.013
0.021
0.048
0.017
1.04
0.071
17-Mar
mg/L
0.024
0.19
0.011
0.021
0.027
0.016
0.95
0.065
19-Mar
mg/L
0.028
0.22
0.012
0.021
0.029
0.019
1.09
0.075
22-Mar
mg/L
0.019
0.25
0.011
0.019
0.04
0.017
1.16
0.079
24-Mar
mg/L
0.023
0.19
0.011
0.027
0.021
0.016
0.94
0.064
26-Mar
mg/L
0.019
0.2
0.011
0.018
0.04
0.018
0.98
0.067
28-Apr
mg/L
0.019
0.2
0.012
0.018
0.037
0.019
< 0.97
< 0.066
Manganese
1.00
0.068
Nitrate/Nitrite Nitrogen
3-Mar
mg/L
<0.04
0.13
0.097
0.14
0.17
0.15
< 1.45
< 0.099
28-Apr
mg/L
<0.04
<0.04
0.091
0.99
<0.04
0.063
< 1.66
< 0.113
Nitrate/Nitrite
Nitrogen
1.56
0.106
Phosphorus
3-Mar
mg/L
<0.05
<0.05
<0.05
<0.05
<0.05
<0.05
28-Apr
mg/L
<0.05
<0.05
<0.05
<0.05
<0.05
<0.05
Sulfate
3-Mar
mg/L
15
65
9.6
23
9.8
8.1
391.48
26.7
8-Mar
mg/L
14
66
9.7
24
11
8.6
393.01
26.8
10-Mar
mg/L
16
61
11
24
12
9.7
390.40
26.6
12-Mar
mg/L
15
69
9.8
23
12
9.9
412.98
28.2
15-Mar
mg/L
15
69
9.9
24
20
8.8
422.28
28.8
17-Mar
mg/L
16
64
11
23
9.9
9.1
396.73
27.1
19-Mar
mg/L
14
64
9
20
10
7
376.39
26
22-Mar
mg/L
14
70
9.6
23
17
8.4
414.25
28.3
24-Mar
mg/L
16
54
11
22
11
9.4
360.18
25
26-Mar
mg/L
14
61
9.6
20
18
8.4
378.64
25.8
28-Apr
mg/L
15
41
9.5
20
20
8.6
312.38
21.3
Sulfate
386.25
26.4
Sulfide
3-Mar
mg/L
<0.7
<0.7
<0.7
<0.7
<0.7
<0.7
8-Mar
mg/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
10-Mar
mg/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
12-Mar
mg/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
15-Mar
mg/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
17-Mar
mg/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
19-Mar
mg/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
22-Mar
mg/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
24-Mar
mg/L
<0.1
<0.1
<0.1
<0.1
<2
<0.1
26-Mar
mg/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
Metals ik
Beryllium
3-Mar
mg/L
0.00068
0.0076
0.00024
0.00041
0.00037
0.00027
0.034
0.0023
8-Mar
mg/L
0.00031
0.0076
0.00022
0.00039
0.00014
0.00031
0.032
0.0022
10-Mar
mg/L
0.00034
0.0081
0.00022
0.00036
0.00015
0.0003
0.034
0.0023
12-Mar
mg/L
0.00034
0.0093
0.00024
0.0004
0.00024
0.00032
0.038
0.0026
15-Mar
mg/L
0.00033
0.0082
0.00022
0.0004
0.00066
0.0003
0.035
0.0024
17-Mar
mg/L
0.00066
0.0092
0.00022
0.00035
0.0002
0.00027
0.040
0.0027
19-Mar
mg/L
0.00067
0.01
0.00024
0.00041
0.00022
0.00031
0.043
0.0029
TR0795A
Page 14 of 28
June 2021

Table 5 Geosyntec Consultants of NC P.C.
Results for Multiple Samples of Untreated Groundwater and Seeps from March/April 2021
Chemours Fayetteville Works, North Carolina
Grouping/Parameter
Date in
2021
Units
EW-1
EW-3
PIW-10S
PIW-5S
SEEP -A-
WALL
SEEP-B-
WALL
Estimated
Load (lb/d)
Estimated
FWMC
22-Mar
mg/L
0.00032
0.011
0.0002
0.00037
0.00051
0.00032
0.045
0.0031
24-Mar
mg/L
0.00055
0.0075
0.00021
0.00044
0.00016
0.00027
0.033
0.0022
26-Mar
mg/L
0.00033
0.0091
0.00024
0.00036
0.00063
0.0003
0.038
0.0026
28-Apr
mg/L
0.0003
0.0081
0.00024
0.00036
0.0005
0.00037
< 0.034
< 0.0023
Beryllium
0.037
0.0025
Cadmium
3-Mar
mg/L
<0.00015
<0.00015
<0.00015
<0.00015
<0.00015
<0.00015
8-Mar
mg/L
<0.00015
<0.00015
<0.00015
<0.00015
<0.00015
<0.00015
10-Mar
mg/L
<0.00015
<0.00015
<0.00015
<0.00015
<0.00015
<0.00015
12-Mar
mg/L
<0.00015
<0.00015
<0.00015
<0.00015
<0.00015
<0.00015
15-Mar
mg/L
<0.00015
<0.00015
<0.00015
<0.00015
<0.00015
<0.00015
17-Mar
mg/L
<0.00015
<0.00015
<0.00015
<0.00015
<0.00015
<0.00015
19-Mar
mg/L
<0.00015
<0.00015
<0.00015
<0.00015
<0.00015
<0.00015
22-Mar
mg/L
<0.00015
<0.00015
<0.00015
<0.00015
<0.00015
<0.00015
24-Mar
mg/L
<0.00015
<0.00015
<0.00015
<0.00015
<0.00015
<0.00015
26-Mar
mg/L
<0.00015
<0.00015
<0.00015
<0.00015
<0.00015
<0.00015
28-Apr
mg/L
<0.00015
<0.00016
<0.00015
<0.00015
<0.00015
<0.00015
Copper
3-Mar
mg/L
0.00036
<0.00036
0.00045
<0.00036
0.0043
0.00047
< 0.011
< 0.00073
8-Mar
mg/L
<0.00036
<0.00036
<0.00036
<0.00036
0.0012
0.00037
< 0.006
< 0.00044
10-Mar
mg/L
<0.00036
<0.00036
<0.00036
<0.00036
0.00097
0.00047
< 0.006
< 0.00043
12-Mar
mg/L
0.00044
<0.00036
0.0004
<0.00036
0.0011
0.00049
< 0.007
< 0.00048
15-Mar
mg/L
<0.00036
<0.00036
<0.00036
0.00051
0.00051
0.00042
< 0.006
< 0.00039
17-Mar
mg/L
<0.00036
<0.00036
<0.00036
0.00081
0.0015
<0.00036
< 0.007
< 0.00049
19-Mar
mg/L
0.0012
<0.00036
<0.00036
<0.00036
0.0014
<0.00036
< 0.012
< 0.00079
22-Mar
mg/L
<0.00036
<0.00036
<0.00036
<0.00036
<0.00036
<0.00036
< 0.005
< 0.00036
24-Mar
mg/L
0.0004
<0.00036
<0.00036
0.0027
0.0021
0.00043
< 0.010
< 0.00071
26-Mar
mg/L
<0.00036
<0.00036
<0.00036
<0.00036
0.00055
0.00054
< 0.006
< 0.00040
28-Apr
mg/L
0.003
0.00066
<0.00036
<0.00036
0.0004
0.00039
< 0.022
< 0.0015
Copper
0.009
0.00061
Cyanide
3-Mar
mg/L
<0.005
<0.005
<0.005
<0.005
<0.005
<0.005
< 0.073
< 0.0050
8-Mar
mg/L
<0.005
<0.005
<0.005
<0.005
<0.005
<0.005
< 0.073
< 0.0050
10-Mar
mg/L
<0.005
<0.005
<0.005
<0.005
<0.005
<0.005
< 0.073
< 0.0050
12-Mar
mg/L
<0.005
<0.005
<0.005
<0.005
<0.005
<0.005
< 0.073
< 0.0050
15-Mar
mg/L
<0.005
<0.005
<0.005
<0.005
<0.005
<0.005
< 0.073
< 0.0050
17-Mar
mg/L
<0.005
<0.005
<0.005
<0.005
<0.005
<0.005
< 0.073
< 0.0050
19-Mar
mg/L
<0.005
<0.005
<0.005
<0.005
0.0078
<0.005
< 0.077
< 0.0052
22-Mar
mg/L
<0.005
<0.005
<0.005
<0.005
<0.005
<0.005
< 0.073
< 0.0050
24-Mar
mg/L
<0.005
<0.005
<0.005
<0.005
<0.005
<0.005
< 0.073
< 0.0050
26-Mar
mg/L
<0.005
<0.005
<0.005
<0.005
<0.005
<0.005
< 0.073
< 0.0050
Cyanide
0.074
0.005
Lead
3-Mar
mg/L
<0.000071
0.00015
0.0012
0.00025
0.0055
0.00047
< 0.010
< 0.0007
8-Mar
mg/L
<0.000071
<0.000071
0.00093
0.00025
0.0012
0.00031
< 0.004
< 0.00026
10-Mar
mg/L
<0.000071
<0.000071
0.00098
0.0003
0.001
0.0004
< 0.004
< 0.00026
12-Mar
mg/L
<0.000071
<0.000071
0.00095
0.00027
0.001
0.0004
< 0.004
< 0.00026
15-Mar
mg/L
<0.000071
<0.000071
0.001
0.00049
0.00097
0.00044
< 0.004
< 0.00028
17-Mar
mg/L
0.000077
<0.000071
0.001
0.00053
0.0022
0.00056
< 0.006
< 0.00041
19-Mar
mg/L
0.00013
<0.000071
0.001
0.00034
0.0016
0.00055
< 0.005
< 0.00036
22-Mar
mg/L
<0.000071
<0.000071
0.00095
0.00028
0.0016
0.00038
< 0.004
< 0.00031
24-Mar
mg/L
<0.000071
<0.000071
0.00097
0.0029
0.0028
0.00054
< 0.009
< 0.00062
26-Mar
mg/L
<0.000071
<0.000071
0.00097
0.00033
0.0016
0.00055
< 0.005
< 0.00033
28-Apr
mg/L
0.000088
0.00032
0.0011
0.00037
0.00096
0.00053
< 0.005
< 0.00036
Lead
0.006
0.00038
Mercury
3-Mar
mg/L
<0.000079
<0.000079
<0.000079
<0.000079
0.000088
0.000086
< 0.001
< 0.00008
8-Mar
mg/L
<0.000079
<0.000079
<0.000079
<0.000079
<0.000079
<0.000079
< 0.001
< 0.00008
10-Mar
mg/L
<0.000079
0.000081
<0.000079
<0.000079
<0.000079
<0.000079
< 0.001
< 0.00008
TR0795A
Page 15 of 28
June 2021

Table 5 Geosyntec Consultants of NC P.C.
Results for Multiple Samples of Untreated Groundwater and Seeps from March/April 2021
Chemours Fayetteville Works, North Carolina
Grouping/Parameter
Date in
2021
Units
EW-1
EW-3
PIW-10S
PIW-5S
SEEP -A-
WALL
SEEP-B-
WALL
Estimated
Load (lb/d)
Estimated
FWMC
12-Mar
mg/L
<0.000079
<0.000079
<0.000079
<0.000079
<0.000079
<0.000079
< 0.001
< 0.00008
15-Mar
mg/L
<0.000079
<0.000079
<0.000079
<0.000079
<0.000079
<0.000079
< 0.001
< 0.00008
17-Mar
mg/L
<0.000079
<0.000079
<0.000079
<0.000079
<0.000079
<0.000079
< 0.001
< 0.00008
19-Mar
mg/L
<0.000079
<0.000079
<0.000079
<0.000079
<0.000079
<0.000079
< 0.001
< 0.00008
22-Mar
mg/L
<0.000079
<0.000079
<0.000079
<0.000079
<0.000079
<0.000079
< 0.001
< 0.00008
24-Mar
mg/L
<0.000079
<0.000079
<0.000079
<0.000079
<0.000079
<0.000079
< 0.001
< 0.00008
26-Mar
mg/L
<0.000079
<0.000079
<0.000079
<0.000079
<0.000079
<0.000079
< 0.001
< 0.00008
28-Apr
mg/L
<0.000079
<0.000079
<0.000079
<0.000079
<0.000079
<0.000079
< 0.001
< 0.00008
Mercury
0.001
0.00008
Selenium
3-Mar
mg/L
<0.00028
<0.00028
<0.00028
<0.00028
0.00039
<0.00028
8-Mar
mg/L
<0.00028
<0.00028
<0.00028
<0.00028
<0.00028
<0.00028
10-Mar
mg/L
<0.00028
<0.00028
<0.00028
<0.00028
<0.00028
<0.00028
12-Mar
mg/L
<0.00028
<0.00028
<0.00028
<0.00028
<0.00028
<0.00028
15-Mar
mg/L
<0.00028
<0.00028
<0.00028
<0.00028
<0.00028
<0.00028
17-Mar
mg/L
<0.00028
<0.00028
<0.00028
<0.00028
<0.00028
<0.00028
19-Mar
mg/L
<0.00028
<0.00028
<0.00028
<0.00028
<0.00028
<0.00028
22-Mar
mg/L
<0.00028
<0.00028
<0.00028
<0.00028
<0.00028
<0.00028
24-Mar
mg/L
<0.00028
<0.00028
<0.00028
<0.00028
<0.00028
<0.00028
26-Mar
mg/L
<0.00028
<0.00028
<0.00028
<0.00028
<0.00028
<0.00028
28-Apr
mg/L
<0.00028
<0.00029
<0.00028
<0.00028
<0.00028
<0.00028
Silver
3-Mar
mg/L
<0.00017
<0.00017
<0.00017
<0.00017
<0.00017
<0.00017
8-Mar
mg/L
<0.00017
<0.00017
<0.00017
<0.00017
<0.00017
<0.00017
10-Mar
mg/L
<0.00017
<0.00017
<0.00017
<0.00017
<0.00017
<0.00017
12-Mar
mg/L
<0.00017
<0.00017
<0.00017
<0.00017
<0.00017
<0.00017
15-Mar
mg/L
<0.00017
<0.00017
<0.00017
<0.00017
<0.00017
<0.00017
17-Mar
mg/L
<0.00017
<0.00017
<0.00017
<0.00017
<0.00017
<0.00017
19-Mar
mg/L
<0.00017
<0.00017
<0.00017
<0.00017
<0.00017
<0.00017
22-Mar
mg/L
<0.00017
<0.00017
<0.00017
<0.00017
<0.00017
<0.00017
24-Mar
mg/L
<0.00017
<0.00017
<0.00017
<0.00017
<0.00017
<0.00017
26-Mar
mg/L
<0.00017
<0.00017
<0.00017
<0.00017
<0.00017
<0.00017
28-Apr
mg/L
<0.00017
<0.00018
<0.00017
<0.00017
<0.00017
<0.00017
Thallium
3-Mar
mg/L
<0.00013
<0.00013
<0.00013
<0.00013
<0.00013
<0.00013
8-Mar
mg/L
<0.00013
<0.00013
<0.00013
<0.00013
<0.00013
<0.00013
10-Mar
mg/L
<0.00013
<0.00013
<0.00013
<0.00013
<0.00013
<0.00013
12-Mar
mg/L
<0.00013
<0.00013
<0.00013
<0.00013
<0.00013
<0.00013
15-Mar
mg/L
<0.00013
<0.00013
<0.00013
<0.00013
<0.00013
<0.00013
17-Mar
mg/L
<0.00013
<0.00013
<0.00013
<0.00013
<0.00013
<0.00013
19-Mar
mg/L
<0.00013
<0.00013
<0.00013
<0.00013
<0.00013
<0.00013
22-Mar
mg/L
<0.00013
<0.00013
<0.00013
<0.00013
<0.00013
<0.00013
24-Mar
mg/L
<0.00013
<0.00013
<0.00013
<0.00013
<0.00013
<0.00013
26-Mar
mg/L
<0.00013
<0.00013
<0.00013
<0.00013
<0.00013
<0.00013
28-Apr
mg/L
<0.00013
<0.00013
<0.00013
<0.00013
<0.00013
<0.00013
Organic Toxic Pollutants (GC/MS Fraction - Base/Neutral Compounds)
1,2-Dichlorobenzene
3-Mar
ug/L
<0.07
<0.07
<0.07
<0.07
<0.07
<0.07
8-Mar
ug/L
<0.07
<0.07
<0.07
<0.07
<0.07
<0.07
10-Mar
ug/L
<0.07
<0.07
<0.07
<0.07
<0.07
<0.07
12-Mar
ug/L
<0.07
<0.07
<0.07
<0.07
<0.07
<0.07
15-Mar
ug/L
<0.07
<0.07
<0.07
<0.07
<0.07
<0.07
17-Mar
ug/L
<0.07
<0.07
<0.07
<0.07
<0.07
<0.07
19-Mar
ug/L
<0.07
<0.07
<0.07
<0.07
<0.07
<0.07
22-Mar
ug/L
<0.07
<0.07
<0.07
<0.07
<0.07
<0.07
24-Mar
ug/L
<0.07
<0.07
<0.07
<0.07
<0.07
<0.07
26-Mar
ug/L
<0.07
<0.07
<0.07
<0.07
<0.07
<0.07
TR0795A
Page 16 of 28
June 2021

Table 5 Geosyntec Consultants of NC P.C.
Results for Multiple Samples of Untreated Groundwater and Seeps from March/April 2021
Chemours Fayetteville Works, North Carolina
Grouping/Parameter
Date in
2021
Units
EW-1
EW-3
PIW-10S
PIW-5S
SEEP -A-
WALL
SEEP-B-
WALL
Estimated
Load (lb/d)
Estimated
FWMC
1,3-Dichlorobenzene
3-Mar
ug/L
<0.06
<0.06
<0.06
<0.06
<0.06
<0.06
8-Mar
ug/L
<0.06
<0.06
<0.06
<0.06
<0.06
<0.06
10-Mar
ug/L
<0.06
<0.06
<0.06
<0.06
<0.06
<0.06
12-Mar
ug/L
<0.06
<0.06
<0.06
<0.06
<0.06
<0.06
15-Mar
ug/L
<0.06
<0.06
<0.06
<0.06
<0.06
<0.06
17-Mar
ug/L
<0.06
<0.06
<0.06
<0.06
<0.06
<0.06
19-Mar
ug/L
<0.06
<0.06
<0.06
<0.06
<0.06
<0.06
22-Mar
ug/L
<0.06
<0.06
<0.06
<0.06
<0.06
<0.06
24-Mar
ug/L
<0.06
<0.06
<0.06
<0.06
<0.06
<0.06
26-Mar
ug/L
<0.06
<0.06
<0.06
<0.06
<0.06
<0.06
1,4-Dichlorobenzene
3-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
8-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
10-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
12-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
15-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
17-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
19-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
22-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
24-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
Organic Toxic Pollutants (GC/MS
1,1,1-Trichloroethane
26-Mar
Fraction
3-Mar
ug/L
- Volatile
ug/L
<0.1
Compounds)
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
8-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
10-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
12-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
15-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
17-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
19-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
22-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
24-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
26-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
1,1,2,2-Tetrachloroethane
3-Mar
ug/L
<0.05
<0.05
<0.05
<0.05
<0.05
<0.05
8-Mar
ug/L
<0.05
<0.05
<0.05
<0.05
<0.05
<0.05
10-Mar
ug/L
<0.05
<0.05
<0.05
<0.05
<0.05
<0.05
12-Mar
ug/L
<0.05
<0.05
<0.05
<0.05
<0.05
<0.05
15-Mar
ug/L
<0.05
<0.05
<0.05
<0.05
<0.05
<0.05
17-Mar
ug/L
<0.05
<0.05
<0.05
<0.05
<0.05
<0.05
19-Mar
ug/L
<0.05
<0.05
<0.05
<0.05
<0.05
<0.05
22-Mar
ug/L
<0.05
<0.05
<0.05
<0.05
<0.05
<0.05
24-Mar
ug/L
<0.05
<0.05
<0.05
<0.05
<0.05
<0.05
26-Mar
ug/L
<0.05
<0.05
<0.05
<0.05
<0.05
<0.05
1,1,2-Trichloroethane
3-Mar
ug/L
<0.2
<0.2
<0.2
<0.2
<0.2
<0.2
8-Mar
ug/L
<0.2
<0.2
<0.2
<0.2
<0.2
<0.2
10-Mar
ug/L
<0.2
<0.2
<0.2
<0.2
<0.2
<0.2
12-Mar
ug/L
<0.2
<0.2
<0.2
<0.2
<0.2
<0.2
15-Mar
ug/L
<0.2
<0.2
<0.2
<0.2
<0.2
<0.2
17-Mar
ug/L
<0.2
<0.2
<0.2
<0.2
<0.2
<0.2
19-Mar
ug/L
<0.2
<0.2
<0.2
<0.2
<0.2
<0.2
22-Mar
ug/L
<0.2
<0.2
<0.2
<0.2
<0.2
<0.2
24-Mar
ug/L
<0.2
<0.2
<0.2
<0.2
<0.2
<0.2
26-Mar
ug/L
<0.2
<0.2
<0.2
<0.2
<0.2
<0.2
1,1-Dichloroethane
3-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
8-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
10-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
TR0795A
Page 17 of 28
June 2021

Table 5 Geosyntec Consultants of NC P.C.
Results for Multiple Samples of Untreated Groundwater and Seeps from March/April 2021
Chemours Fayetteville Works, North Carolina
Grouping/Parameter
Date in
2021
Units
EW-1
EW-3
PIW-10S
PIW-5S
SEEP -A-
WALL
SEEP-B-
WALL
Estimated
Load (lb/d)
Estimated
FWMC
12-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
15-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
17-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
19-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
22-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
24-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
26-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
1,1-Dichloroethene
3-Mar
ug/L
<0.2
<0.2
<0.2
<0.2
<0.2
<0.2
8-Mar
ug/L
<0.2
<0.2
<0.2
<0.2
<0.2
<0.2
10-Mar
ug/L
<0.2
<0.2
<0.2
<0.2
<0.2
<0.2
12-Mar
ug/L
<0.2
<0.2
<0.2
<0.2
<0.2
<0.2
15-Mar
ug/L
<0.2
<0.2
<0.2
<0.2
<0.2
<0.2
17-Mar
ug/L
<0.2
<0.2
<0.2
<0.2
<0.2
<0.2
19-Mar
ug/L
<0.2
<0.2
<0.2
<0.2
<0.2
<0.2
22-Mar
ug/L
<0.2
<0.2
<0.2
<0.2
<0.2
<0.2
24-Mar
ug/L
<0.2
<0.2
<0.2
<0.2
<0.2
<0.2
26-Mar
ug/L
<0.2
<0.2
<0.2
<0.2
<0.2
<0.2
1,2-Dichloroethane
3-Mar
ug/L
<0.3
<0.3
<0.3
<0.3
<0.3
<0.3
8-Mar
ug/L
<0.3
<0.3
<0.3
<0.3
<0.3
<0.3
10-Mar
ug/L
<0.3
<0.3
<0.3
<0.3
<0.3
<0.3
12-Mar
ug/L
<0.3
<0.3
<0.3
<0.3
<0.3
<0.3
15-Mar
ug/L
<0.3
<0.3
<0.3
<0.3
<0.3
<0.3
17-Mar
ug/L
<0.3
<0.3
<0.3
<0.3
<0.3
<0.3
19-Mar
ug/L
<0.3
<0.3
<0.3
<0.3
<0.3
<0.3
22-Mar
ug/L
<0.3
<0.3
<0.3
<0.3
<0.3
<0.3
24-Mar
ug/L
<0.3
<0.3
<0.3
<0.3
<0.3
<0.3
26-Mar
ug/L
<0.3
<0.3
<0.3
<0.3
<0.3
<0.3
1,2-Dichloropropane
3-Mar
ug/L
<0.2
<0.2
<0.2
<0.2
<0.2
<0.2
8-Mar
ug/L
<0.2
<0.2
<0.2
<0.2
<0.2
<0.2
10-Mar
ug/L
<0.2
<0.2
<0.2
<0.2
<0.2
<0.2
12-Mar
ug/L
<0.2
<0.2
<0.2
<0.2
<0.2
<0.2
15-Mar
ug/L
<0.2
<0.2
<0.2
<0.2
<0.2
<0.2
17-Mar
ug/L
<0.2
<0.2
<0.2
<0.2
<0.2
<0.2
19-Mar
ug/L
<0.2
<0.2
<0.2
<0.2
<0.2
<0.2
22-Mar
ug/L
<0.2
<0.2
<0.2
<0.2
<0.2
<0.2
24-Mar
ug/L
<0.2
<0.2
<0.2
<0.2
<0.2
<0.2
26-Mar
ug/L
<0.2
<0.2
<0.2
<0.2
<0.2
<0.2
Acrolein
3-Mar
ug/L
<1
<1
<1
<1
<1
<1
8-Mar
ug/L
<1
<1
<1
<1
<1
<1
10-Mar
ug/L
<1
<1
<1
<1
<1
<1
12-Mar
ug/L
<1
<1
<1
<1
<1
<1
15-Mar
ug/L
<1
<1
<1
<1
<1
<1
17-Mar
ug/L
<1
<1
<1
<1
<1
<1
19-Mar
UG/L
<1
<1
<1
<1
<1
<1
22-Mar
ug/L
<1
<1
<1
<1
<1
<1
24-Mar
ug/L
<1
<1
<1
<1
<1
<1
26-Mar
ug/L
<1
<1
<1
<1
<1
<1
Acrylonitrile
3-Mar
ug/L
<0.2
<0.2
<0.2
<0.2
<0.2
<0.2
8-Mar
ug/L
<0.2
<0.2
<0.2
<0.2
<0.2
<0.2
10-Mar
ug/L
<0.2
<0.2
<0.2
<0.2
<0.2
<0.2
12-Mar
ug/L
<0.2
<0.2
<0.2
<0.2
<0.2
<0.2
15-Mar
ug/L
<0.2
<0.2
<0.2
<0.2
<0.2
<0.2
17-Mar
ug/L
<0.2
<0.2
<0.2
<0.2
<0.2
<0.2
19-Mar
ug/L
<0.2
<0.2
<0.2
<0.2
<0.2
<0.2
TR0795A
Page 18 of 28
June 2021

Table 5 Geosyntec Consultants of NC P.C.
Results for Multiple Samples of Untreated Groundwater and Seeps from March/April 2021
Chemours Fayetteville Works, North Carolina
Grouping/Parameter
Date in
2021
Units
EW-1
EW-3
PIW-10S
PIW-5S
SEEP -A-
WALL
SEEP-B-
WALL
Estimated
Load (lb/d)
Estimated
FWMC
22-Mar
ug/L
<0.2
<0.2
<0.2
<0.2
<0.2
<0.2
24-Mar
ug/L
<0.2
<0.2
<0.2
<0.2
<0.2
<0.2
26-Mar
ug/L
<0.2
<0.2
<0.2
<0.2
<0.2
<0.2
Benzene
3-Mar
ug/L
<0.05
<0.05
<0.05
<0.05
<0.05
<0.05
8-Mar
ug/L
<0.05
<0.05
<0.05
<0.05
<0.05
<0.05
10-Mar
ug/L
<0.05
<0.05
<0.05
<0.05
<0.05
<0.05
12-Mar
ug/L
<0.05
<0.05
<0.05
<0.05
<0.05
<0.05
15-Mar
ug/L
<0.05
<0.05
<0.05
<0.05
<0.05
<0.05
17-Mar
ug/L
<0.05
<0.05
<0.05
<0.05
<0.05
<0.05
19-Mar
ug/L
<0.05
<0.05
<0.05
<0.05
<0.05
<0.05
22-Mar
ug/L
<0.05
<0.05
<0.05
<0.05
<0.05
<0.05
24-Mar
ug/L
<0.05
<0.05
<0.05
<0.05
<0.05
<0.05
26-Mar
ug/L
<0.05
<0.05
<0.05
<0.05
<0.05
<0.05
Bromodichloromethane
3-Mar
ug/L
<0.2
<0.2
<0.2
<0.2
<0.2
<0.2
8-Mar
ug/L
<0.2
<0.2
<0.2
<0.2
<0.2
<0.2
10-Mar
ug/L
<0.2
<0.2
<0.2
<0.2
<0.2
<0.2
12-Mar
ug/L
<0.2
<0.2
<0.2
<0.2
<0.2
<0.2
15-Mar
ug/L
<0.2
<0.2
<0.2
<0.2
<0.2
<0.2
17-Mar
ug/L
<0.2
<0.2
<0.2
<0.2
<0.2
<0.2
19-Mar
ug/L
<0.2
<0.2
<0.2
<0.2
<0.2
<0.2
22-Mar
ug/L
<0.2
<0.2
<0.2
<0.2
<0.2
<0.2
24-Mar
ug/L
<0.2
<0.2
<0.2
<0.2
<0.2
<0.2
26-Mar
ug/L
<0.2
<0.2
<0.2
<0.2
<0.2
<0.2
Bromoform
3-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
8-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
10-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
12-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
15-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
17-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
19-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
22-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
24-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
26-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
Carbon Tetrachloride
3-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
8-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
10-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
12-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
15-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
17-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
19-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
22-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
24-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
26-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
Chlorobenzene
3-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
8-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
10-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
12-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
15-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
17-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
19-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
22-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
24-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
26-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
TR0795A
Page 19 of 28
June 2021

Table 5 Geosyntec Consultants of NC P.C.
Results for Multiple Samples of Untreated Groundwater and Seeps from March/April 2021
Chemours Fayetteville Works, North Carolina
Grouping/Parameter
Date in
2021
Units
EW-1
EW-3
PIW-10S
PIW-5S
SEEP -A-
WALL
SEEP-B-
WALL
Estimated
Load (lb/d)
Estimated
FWMC
Chlorodibromomethane
3-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
8-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
10-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
12-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
15-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
17-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
19-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
22-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
24-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
26-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
Chloroform
3-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
8-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
10-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
12-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
15-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
17-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
19-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
22-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
24-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
26-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
Ethylbenzene
3-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
8-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
10-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
12-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
15-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
17-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
19-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
22-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
24-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
26-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
Methylene Chloride
3-Mar
ug/L
<0.3
<0.3
<0.3
<0.3
<0.3
<0.3
8-Mar
ug/L
<0.3
<0.3
<0.3
<0.3
<0.3
<0.3
10-Mar
ug/L
<0.3
<0.3
<0.3
<0.3
<0.3
<0.3
12-Mar
ug/L
<0.3
<0.3
<0.3
<0.3
<0.3
<0.3
15-Mar
ug/L
<0.3
<0.3
<0.3
<0.3
<0.3
<0.3
17-Mar
ug/L
<0.3
<0.3
<0.3
<0.3
<0.3
<0.3
19-Mar
ug/L
<0.3
<0.3
<0.3
<0.3
<0.3
<0.3
22-Mar
ug/L
<0.3
<0.3
<0.3
<0.3
<0.3
<0.3
24-Mar
ug/L
<0.3
<0.3
<0.3
<0.3
<0.3
<0.3
26-Mar
ug/L
<0.3
<0.3
<0.3
<0.3
<0.3
<0.3
Toluene
3-Mar
ug/L
<0.05
<0.05
<0.05
<0.05
<0.05
<0.05
8-Mar
ug/L
<0.05
<0.05
<0.05
<0.05
<0.05
<0.05
10-Mar
ug/L
<0.05
<0.05
<0.05
<0.05
<0.05
<0.05
12-Mar
ug/L
<0.05
<0.05
<0.05
<0.05
<0.05
<0.05
15-Mar
ug/L
<0.05
<0.05
<0.05
<0.05
<0.05
<0.05
17-Mar
ug/L
<0.05
<0.05
<0.05
<0.05
<0.05
<0.05
19-Mar
ug/L
<0.05
<0.05
<0.05
<0.05
<0.05
<0.05
22-Mar
ug/L
<0.05
<0.05
<0.05
<0.05
<0.05
<0.05
24-Mar
ug/L
<0.05
<0.05
<0.05
<0.05
<0.05
<0.05
26-Mar
ug/L
<0.05
<0.05
<0.05
<0.05
<0.05
<0.05
Vinyl Chloride
3-Mar
ug/L
<0.3
<0.3
<0.3
<0.3
<0.3
<0.3
8-Mar
ug/L
<0.3
<0.3
<0.3
<0.3
<0.3
<0.3
10-Mar
ug/L
<0.3
<0.3
<0.3
<0.3
<0.3
<0.3
12-Mar
ug/L
<0.3
<0.3
<0.3
<0.3
<0.3
<0.3
TR0795A
Page 20 of 28
June 2021

Table 5 Geosyntec Consultants of NC P.C.
Results for Multiple Samples of Untreated Groundwater and Seeps from March/April 2021
Chemours Fayetteville Works, North Carolina
Grouping/Parameter
Date in
2021
Units
EW-1
EW-3
PIW-10S
PIW-5S
SEEP -A-
WALL
SEEP-B-
WALL
Estimated
Load (lb/d)
Estimated
FWMC
15-Mar
ug/L
<0.3
<0.3
<0.3
<0.3
<0.3
<0.3
17-Mar
ug/L
<0.3
<0.3
<0.3
<0.3
<0.3
<0.3
19-Mar
ug/L
<0.3
<0.3
<0.3
<0.3
<0.3
<0.3
22-Mar
ug/L
<0.3
<0.3
<0.3
<0.3
<0.3
<0.3
24-Mar
ug/L
<0.3
<0.3
<0.3
<0.3
<0.3
<0.3
26-Mar
ug/L <0.3
<0.3
<0.3
<0.3 <0.3 <0.3
Radioactivity
ql1r
. RIF 111P
A
Radium (total)
3-Mar
pCi/L
<0.308
<0.315
2.84
5.69
_
<1.9
<0.48
< 0.0139
<
0.95
8-Mar
pCi/L
<0.531
<0.606
2.77
4.46
<0.867
<0.32
< 0.0219
<
1.50
10-Mar
pCi/L
<1.15
2.36
3.1
3.21
<0
<0.314
< 0.0183
<
1.25
12-Mar
pCi/L
<0.885
<0.598
3.86
4.76
<0.688
<1.05
< 0.0260
<
1.77
15-Mar
pCi/L
<1.11
<1.18
4.12
4.71
3.27
<1.43
< 0.0225
<
1.54
17-Mar
pCi/L
<0.7
<1.46
4.74
5.57
<0.753
<1.31
< 0.0235
<
1.60
19-Mar
pCi/L
<1.83
<0.648
4.12
4.14
<1.15
<0.7
< 0.0222
<
1.51
22-Mar
pCi/L
<1.35
<0.548
4.49
4.29
2.61
<0.483
< 0.0045
<
0.31
Radium (total)
0.0191
1.3022
Radium-226
3-Mar
pCi/L
<0.203
<0
<0.354
<0.699
1.58
<0.131
< 0.0098
<
0.67
8-Mar
pCi/L
<0.107
<0.528
0.467
<0.308
<0.193
<0.118
< 0.0047
<
0.32
10-Mar
pCi/L
0.615
1.31
<0.56
<0.488
<0
<0.169
< 0.0017
<
0.12
12-Mar
pCi/L
<0.18
<0.324
0.949
<0.8
<0.121
<0.369
< 0.0025
<
0.17
15-Mar
pCi/L
<-0.305
<0.22
<0.543
0.784
<0.431
0.456
< 0.0086
<
0.58
17-Mar
pCi/L
<-0.0278
<0.188
0.984
<0.434
<-0.0586
<0.43
< 0.0051
<
0.35
19-Mar
pCi/L
<0.79
<0.354
<0.756
<0.578
<0.0725
<0.683
< 0.0100
<
0.68
22-Mar
pCi/L
<0.521
<0.0652
<0.799
<0.841
<0.157
<0.0663
< 0.0101
<
0.69
Radium-226
0.0066
0.45
Radium-228
3-Mar
pCi/L
<0.105
<0.315
2.49
4.99
<0.323
<0.349
< 0.0136
<
0.93
8-Mar
pCi/L
<0.424
<0.078
2.3
4.15
<0.674
<0.202
< 0.0225
<
1.53
10-Mar
pCi/L
<0.535
1.05
2.54
2.72
<-0.061
<0.145
< 0.0198
<
1.35
12-Mar
pCi/L
<0.705
<0.274
2.91
3.96
<0.567
<0.679
< 0.0149
<
1.02
15-Mar
pCi/L
<1.11
<0.962
3.58
3.93
2.84
<0.972
< 0.0170
<
1.16
17-Mar
pCi/L
<0.7
<1.27
3.76
5.14
<0.753
<0.876
< 0.0000
<
0.00
19-Mar
pCi/L
<1.04
<0.294
3.36
3.56
1.08
<0.0173
< 0.0015
<
0.10
22-Mar
pCi/L
<0.829
<0.483
3.69
3.45
2.45
<0.417
< 0.0015
<
0.10
Radium-228
0.0113
0.77
Other Parameters
1,3-Dichloropropane
3-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
8-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
10-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
12-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
15-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
17-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
19-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
22-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
24-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
26-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
Bicarbonate
3-Mar
mg/L
3.1
<2.6
<2.6
<2.6
16
<2.6
< 58.323
<
4.0
28-Apr
mg/L
3.3
<2.6
<2.6
<2.6
<2.6
<2.6
< 42.202
<
2.9
Bicarbonate
50.263
3.4
Carbonate
3-Mar
mg/L
<2.6
<2.6
<2.6
<2.6
<2.6
<2.6
28-Apr
mg/L
<2.6
<2.6
<2.6
<2.6
<2.6
<2.6
Chloride
3-Mar
mg/L
6.6
13
3.7
5.4
5
5
112.088
7.6
8-Mar
mg/L
6.7
14
4.1
5.9
5.3
5.7
119.000
8.1
10-Mar
mg/L
6.8
14
3.9
5.9
4.8
5.5
118.401
8.1
12-Mar
mg/L
6.3
14
4
5.5
4.2
6.5
116.298
7.9
TR0795A
Page 21 of 28
June 2021

Table 5 Geosyntec Consultants of NC P.C.
Results for Multiple Samples of Untreated Groundwater and Seeps from March/April 2021
Chemours Fayetteville Works, North Carolina
Grouping/Parameter
Date in
2021
Units
EW-1
EW-3
PIW-10S
PIW-5S
SEEP -A-
WALL
SEEP-B-
WALL
Estimated
Load (lb/d)
Estimated
FWMC
15-Mar
mg/L
6.6
14
3.1
5.5
4
5.2
114.588
7.8
17-Mar
mg/L
7.5
14
4.1
5.7
4.5
5.3
121.671
8.3
19-Mar
mg/L
6.7
12
4
6.2
4.5
5.5
110.315
7.5
22-Mar
mg/L
6.8
13
4.1
6.3
4.8
5.8
115.803
7.9
24-Mar
mg/L
6.9
11
4
5.7
4.6
5.6
107.537
7.3
26-Mar
mg/L
7.4
13
5.3
5.8
5.3
7.8
124.244
8.5
28-Apr
mg/L
8
11
5.5
5.9
5
6.9
118.377
8.1
Chloride
116.211
7.9
COLOR APPARENT
3-Mar
PCU
<5
<5
30
<5
60
35
28-Apr
PCU
<5
<5
<5
<5
<5
30
Dissolved Organic Carbon
28-Apr
ug/L
680
Ethyl Chloride
3-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
8-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
10-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
12-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
15-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
17-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
19-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
22-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
24-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
26-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
Phosphorus as PO4
3-Mar
mg/L
<0.25
<0.25
<0.25
<0.25
<0.25
<0.25
28-Apr
mg/L
<0.25
<0.25
<0.25
<0.25
<0.25
<0.25
Silica
3-Mar
mg/L
22
24
10
12
5.5
6.7
< 259.262
< 17.7
28-Apr
mg/L
22
18
<0.05
18
18
10
< 258.055
< 17.6
Silica
258.658
17.7
Total Dissolved Solids
3-Mar
mg/L
51� 120
27
46
63
26
949.562
64.8
28-Apr
mg/L
I 63
<12
33
56
43
42
< 635.150
< 43.3
Total Dissolved Solids
792.356
54.1
Total Hardness As CaCO3
3-Mar
mg/L
12
45
3.7
8.5
21
5
< 287.667
< 19.6
8-Mar
mg/L
11
44
3.5
8.5
21
5.1
278.096
19.0
10-Mar
mg/L
11
38
3.6
8.3
17
5
250.101
17.1
12-Mar
mg/L
12
42
3.6
8.6
15
4.9
268.505
18.3
15-Mar
mg/L
12
50
4.1
9.3
10
5
293.364
20.0
17-Mar
mg/L
11
39
3.6
9.1
14
4.7
250.233
17.1
19-Mar
mg/L
12
43
3.9
9.1
16
4.9
274.296
18.7
22-Mar
mg/L
11
42
3.5
8.4
10
6.4
258.824
17.7
24-Mar
mg/L
10
40
3.2
7.7
13
4.1
243.895
16.6
26-Mar
mg/L
11
39
3.7
7.6
8.8
4.9
242.418
16.5
28-Apr
mg/L
12
42
4.2
8.3
8.4
4.7
259.739
17.7
Total Hardness As CaCO3
264.285
18.0
trans-1,2-Dichloroethene
3-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
8-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
10-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
12-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
15-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
17-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
19-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
22-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
24-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
26-Mar
ug/L
<0.1
<0.1
<0.1
<0.1
<0.1
<0.1
TR0795A
Page 22 of 28
June 2021

Table 5 Geosyntec Consultants of NC P.C.
Results for Multiple Samples of Untreated Groundwater and Seeps from March/April 2021
Chemours Fayetteville Works, North Carolina
Grouping/Parameter
Date in
2021
Units
EW-1
EW-3
PIW-10S
PIW-5S
SEEP -A-
WALL
SEEP-B-
WALL
Estimated
Load (lb/d)
Estimated
FWMC
Trichloroethene
3-Mar
ug/L
<0.2
<0.2
<0.2
<0.2
<0.2
<0.2
8-Mar
ug/L
<0.2
<0.2
<0.2
<0.2
<0.2
<0.2
10-Mar
ug/L
<0.2
<0.2
<0.2
<0.2
<0.2
<0.2
12-Mar
ug/L
<0.2
<0.2
<0.2
<0.2
<0.2
<0.2
15-Mar
ug/L
<0.2
<0.2
<0.2
<0.2
<0.2
<0.2
17-Mar
ug/L
<0.2
<0.2
<0.2
<0.2
<0.2
<0.2
19-Mar
ug/L
<0.2
<0.2
<0.2
<0.2
<0.2
<0.2
22-Mar
ug/L
<0.2
<0.2
<0.2
<0.2
<0.2
<0.2
24-Mar
ug/L
<0.2
<0.2
<0.2
<0.2
<0.2
<0.2
26-Mar
ug/L
<0.2
<0.2
<0.2
<0.2
<0.2
<0.2
Notes
mg/L - milligrams per liter
ug/L - microgram per liter
pCi/L - picocuries per liter
TR0795A Page 23 of 28 June 2021

Table 6 Geosyntec Consultants of NC P.C.
Comparison of Flow -Weighted Mean Concentrations to Water Quality Criteria
Chemours Fayetteville Works, North Carolina
FWMC for Outfall 004 (Untreated)
March/April 2021 Sampling
Grouping/Parameter
Units
At Reporting
Limit (RL)
At 1/2 RL
RL set to 0
Water Quality
Criterionl,2,3
Table A. Conventional and Non -Conventional Parameters
Chemical Oxygen Demand (COD)
mg/L
25
8
1
NA
Total Organic Carbon
mg/L
2.94
1.60
1.53
NA
Table B. Certain Conventional and Non -Conventional Parameters
Aluminum
mg/L
1.57
0.89
0.89
I 6.5
Barium
mg/L
0.046
0.026
0.026
1.0
Boron
mg/L
0.012
0.008
0.003
0.15
Cobalt
mg/L
0.0009
0.0008
0.0008
0.0016
Flouride
mg/L
0.27
0.16
0.06
1.8
Iron
mg/L
3.65
3.65
3.65
1.0
Magnesium
mg/L
2.19
1.25
1.25
NA
Manganese
mg/L
0.07
0.07
0.07
0.05
Nitrate/Nitrite Nitrogen
mg/L
0.11
0.09
0.08
10
Sulfate
mg/L
26
26
26
250
Titanium
mg/L
0.055
0.030
0.029
NA
total residual chlorine
mg/L
0.155
0.088
0.088
0.017
Radium (total)
pCi/L
1.302
0.001
0.001
5
Radium-226
pCi/L
0.448
0.000
0.000
5
Metals
Arsenic
mg/L
0.0008
0.0003
0.0001
0.01
Beryllium
mg/L
0.0025
0.0025
0.0025
0.0065
Chromium
mg/L
0.0014
0.0008
0.0007
0.0238
Copper
mg/L
0.00061
0.00050
0.00040
0.00274
Cyanide
mg/L
0.005
0.003
0.000
0.004
Lead
mg/L
0.00038
0.00036
0.00034
0.00054
Mercury
mg/L
0.000079
0.000041
0.000019
0.000012
Nickel
mg/L
0.0017
0.0009
0.0009
0.0161
Zinc
mg/L
0.033
0.019
0.018
0.037
Organic Toxic Pollutants (GC/MS Fraction - Base/Neutral Compounds)
'
Acenaphthene
ug/L
0.42
0.20
0.16
60
Anthracene
ug/L
0.19
0.14
0.086
0.05
Benzo(A)Anthracene
ug/L
0.37
0.22
0.071
0.0028
Benzo(A)Pyrene
ug/L
0.32
0.17
0.017
0.0028
Benzo(B)Fluoranthene
ug/L
0.33
0.18
0.026
0.0028
Benzo(K)Fluoranthene
ug/L
0.16
0.09
0.014
0.0028
Chrysene
ug/L
0.36
0.21
0.06
0.0028
Fluoranthene
ug/L
0.76
0.61
0.46
0.11
Fluorene
ug/L
0.69
0.54
0.39
30
TR0795A
Page 24 of 28
June 2021

Table 6 Geosyntec Consultants of NC P.C.
Comparison of Flow -Weighted Mean Concentrations to Water Quality Criteria
Chemours Fayetteville Works, North Carolina
FWMC for Outfall 004 (Untreated)
March/April 2021 Sampling
Grouping/Parameter
Units
At Reporting
Limit (RL)
At 1/2 RL
RL set to 0
Water Quality
Cr. . 1,2,3
Naphthalene
ug/L
0.68
0.60
0.53
12
Phenanthrene
ug/L
1.29
1.22
1.14
0.7
Pyrene
ug/L
0.55
0.40
0.25
20
Organic Toxic Pollutants (GC/MS Fraction - Pesticides)
Endosulfan I
ug/L
0.006
0.005
0.003
20
Heptachlor Epoxide
ug/L
0.007
0.004
0.002
0.000032
Notes
1 Hardness based metals (chromium, copper, lead, nickel, and zinc) criteria calculated assuming 25 mg/L CaCO3.
2 Total of all PAHs (benzo(A)anthracene, benzo(A)pyrene, benzo(B)fluoranthene, and benzo(K)fluoranthene, and
chrysene) should not exceed 2.8 ng/L.
s Iron and manganese concentrations are provided for guidance purposes
mg/L - milligrams per liter
ug/L - microgram per liter
pCi/L - picocuries per liter
TR0795A Page 25 of 28 June 2021

Table 7 Geosyntec Consultants of NC P.C.
Comparison of Flow -Weighted Mean Concentrations to Water Quality Criteria with an 8:1 Dilution
Chemours Fayetteville Works, North Carolina
FWMC for Outfall 004 (Untreated)
March/April 2021 Sampling
Grouping/Parameter
Units
At
Reporting
Limit (RL)
At 1/2 RL
RL set to 0
Water
Quality
Criterion1,2
Table B. Certain Conventional and Non -Conventional Parameters
total residual chlorine
mg/L
0.155
0.088
0.088
0.136
Organic Toxic Pollutants (GC/MS Fraction - Base/Neutral Compounds)
Benzo(A)Anthracene
ug/L
0.37
0.22
0.07
0.0224
Benzo(A)Pyrene
ug/L
0.32
0.17
0.017
0.0224
Benzo(B)Fluoranthene
ug/L
0.33
0.18
0.03
0.0224
Benzo(K)Fluoranthene
ug/L
0.16
0.09
0.01
0.0224
Chrysene
ug/L
0.36
0.21
0.06
0.0224
Organic Toxic Pollutants (GC/MS Fraction - Pesticides)
Heptachlor Epoxide
ug/L
0.007
0.004
0.002
0.000256
Notes
1 Criterion increased by factor of 8 to account for 8:1 dilution with Cape Fear River.
2 Total of all PAHs (benzo(A)anthracene, benzo(A)pyrene, benzo(B)fluoranthene, benzo(K)fluoranthene,
and chrysene) should not exceed 2.8 ng/L (22.4 ng/L at an 8:1 dilution).
mg/L - milligrams per liter
ug/L - microgram per liter
TR0795A Page 26 of 28 June 2021

Table 8 Geosyntec Consultants of NC P.C.
Load Calculations for Mass Balance of GWTS (Outfall 004) with Outfall 002
Chemours Fayetteville Works, North Carolina
Load for Untreated Outfall 004
(lb/d)
Outfall 002 Max Conc or
LTA (Form 2C)
Outfall 002 Load (b/d)
Grouping/Parameter
At Reporting
Limit (RL)
At 1/2 RL
RL set to
0
Conc.
Units
At Reporting
Limit (RL)
At 1/2 RL
RL set to
0
Table A. Conventional and Non -Conventional Parameters
T
Chemical Oxygen Demand (COD) 369
202
35
35.8
mg/L
5,385
5,385
5,385
Total Organic Carbon 43.1
41.3
39.4
5.3
mg/L
797.3
797.3
797.3
Table B. Certain Conventional and Non -Conventional Parameters
Aluminum
23
23
23
0.222
mg/L
33
33
33
Barium
0.7
0.7
0.7
0.0235
mg/L
3.5
3.5
3.5
Boron
0.2
0.1
0.0
0.0262
mg/L
3.9
3.9
3.9
Cobalt
0.013
0.012
0.011
0.00064
mg/L
0.10
0.10
0.10
Flouride
3.9
2.4
0.9
0.1
mg/L
15.0
15.0
15.0
Iron
54
54
54
1.05
mg/L
158
158
158
Magnesium
32
32
32
2.79
mg/L
420
420
420
Manganese
1.0
1.0
1.0
0.121
mg/L
18.2
18.2
18.2
Nitrate/Nitrite Nitrogen
1.6
1.4
1.2
0.46
mg/L
69.2
69.2
69.2
Sulfate
386
386
386
32.1
mg/L
4,829
4,829
4,829
Titanium
0.8
0.8
0.7
0.0078
mg/L
1.2
1.2
1.2
total residual chlorine
2.3
2.3
2.3
0.00036
mg/L
0.1
0.1
0.1
Radium (total)
0.019
0.014
0.009
< 1.39
pCi/L
0.2
0.1
0
Radium-226
0.007
0.005
0.003
1.15
pCi/L
0.2
0.2
0.2
Metals
I
Arsenic
0.012
0.007
0.003
0.00075
mg/L
0.1
0.1
0.1
Beryllium
0.04
0.04
0.04
< 0.000091
mg/L
0.01
0.01
0
Chromium
0.02
0.02
0.02
0.0011
mg/L
0.2
0.2
0.2
Copper
0.01
0.01
0.01
< 0.0099
mg/L
1.5
0.7
0
Cyanide
0.07
0.04
0
< 0.005
mg/L
0.8
0.4
0
Lead
0.01
0.01
0
< 0.0011
mg/L
0.2
0.1
0
Mercury
0.0012
0.0006
0.00005
0.00000471
mg/L
0.0007
0.0007
0.0007
Nickel
0.02
0.02
0.02
0.0016
mg/L
0.2
0.2
0.2
Zinc
0.5
0.5
0.5
0.0094
mg/L
1.4
1.4
1.4
Organic Toxic Pollutants (GC/MS Fraction - Base/Neutral Compounds)
Acenaphthene
0.006
0.005
0.004
< 0.08
ug/L
0.012
0.006
0
Anthracene
0.003
0.0020
0.0013
< 0.07
ug/L
0.011
0.005
0
Benzo(A)Anthracene
0.005
0.003
0.001
< 0.2
ug/L
0.030
0.015
0
Benzo(A)Pyrene
0.005
0.0025
0.0003
< 0.2
ug/L
0.030
0.015
0
Benzo(B)Fluoranthene
0.0048
0.0026
0.0004
< 0.07
ug/L
0.011
0.005
0
Benzo(K)Fluoranthene
0.002
0.001
0.0002
< 0.09
ug/L
0.014
0.007
0
Chrysene
0.005
0.003
0.001
< 0.2
ug/L
0.030
0.015
0
Fluoranthene
0.011
0.009
0.007
< 0.2
ug/L
0.030
0.015
0
Fluorene
0.010
0.008
0.006
< 0.08
ug/L
0.012
0.006
0
Naphthalene
0.01
0.01
0.01
< 0.09
ug/L
0.014
0.007
0
Phenanthrene
0.019
0.018
0.017
< 0.09
ug/L
0.014
0.007
0
Pyrene
0.008
0.006
0.004
< 0.2
ug/L
0.030
0.015
0
Organic Toxic Pollutants (GC/MS Fraction
- Pesticides)
0.0001
0.0000
< 0.0028
ug/L
0.0004
0.0002
0
Endosulfan I
0.0001
Heptachlor Epoxide
0.00010
0.00007
0.00003
< 0.00466
ug/L
0.0007
0.0004
0
Notes
mg/L - milligrams per liter
ug/L - microgram per liter
pCi/L - picocuries per liter
TR0795A
Page 27 of 28
June 2021

Table 9 Geosyntec Consultants of NC P.C.
Comparison of Flow -Weighted Mean Concentrations for Combined Outfalls 002 and 004 to Water Quality
Criteria with an 8:1 Dilution
Chemours Fayetteville Works, North Carolina
FWMC for Outfalls 002 (Treated) and
004 (Untreated)
Grouping/Parameter
Units
At Reporting
Limit (RL)
At 1/2 RL
RL set to 0
Water
Quality
12
Criterion '
Table B. Certain Conventional and Non -Conventional Parameters
total residual chlorine
mg/L
0.014
0.014
0.014
0.136
Organic Toxic Pollutants (GC/MS Fraction - Base/Neutral Compounds)
Benzo(A)Anthracene
ug/L
0.22
0.11
0.0063
0.0224
Benzo(A)Pyrene
ug/L
0.21
0.11
0.0015
0.0224
Benzo(B)Fluoranthene
ug/L
0.09
0.05
0.0023
0.0224
Benzo(K)Fluoranthene
ug/L
0.096
0.049
0.0013
0.0224
Chrysene
ug/L
0.214
0.110
0.0053
0.0224
Organic Toxic Pollutants (GC/MS Fraction - Pesticides)
I III
Heptachlor Epoxide
ug/L
0.00484
0.00252
0.0002
0.000256
Notes
1 Criterion increased by factor of 8 to account for dilution with Cape Fear River.
2 Total of all PAHs (benzo(A)anthracene, benzo(A)pyrene, benzo(B)fluoranthene, benzo(K)fluoranthene, and
fluorene) should not exceed 2.8 ng/L (22.4 ng/L at an 8:1 dilution).
mg/L - milligrams per liter
ug/L - microgram per liter
Page 28 June 2021

Attachment A.5 - Engineering Report —
Treatment of Groundwater and Upgradient
Seeps Water

Geosyntecl>
consultants
Geosyntec Consultants of NC, P.C.
NC License No.: C-3500 and C-295
ENGINEERING REPORT -
TREATMENT OF GROUNDWATER
AND UPGRADIENT SEEPS WATER
Prepared for
The Chemours Company FC, LLC
1007 Market Street
PO Box 2047
Wilmington, DE 19899
Prepared by
Geosyntec Consultants of NC, P.C.
2501 Blue Ridge Road, Suite 430
Raleigh, NC 27607
Geosyntec Project Number TR0795
June 2021

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consultants
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TABLE OF CONTENTS
1. INTRODUCTION AND BACKGROUND 5
1.1 Site History and Overview 5
1.2 Process Overview 6
2. DESIGN BASIS 8
2.1 Aquifer Location 8
2.2 Influent Water Quality 10
2.3 Groundwater and Seeps Outfall 13
2.4 Influent Untreated Water Quality — Comparison to Water Quality Criterial3
2.5 Pilot Studies 15
2.6 Pumping & Conveyance Design 15
3. PROPOSED TREATMENT DESIGN 16
3.1 Overall Narrative 16
3.2 Individual Unit Operations 19
3.2.1 Metals Oxidation 19
3.2.2 Filtration 19
3.2.3 Granular Activated Carbon Adsorption 19
3.2.4 Solids Handling and Dewatering 20
3.3 Operability and Maintenance Considerations 20
3.4 Process Monitoring 21
4. SUMMARY 21
5. REFERENCES 21
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LIST OF TABLES
Table 1: Hydraulic Loading of Representative Groundwater and Seep Sources
Table 2: Representative Well and Seep Locations and Estimated Flowrates
Table 3: Influent Design Basis for the Groundwater Treatment System
LIST OF FIGURES
Figure 1: Remedy Alignment and Proposed Groundwater Treatment System Location
Figure 2: Groundwater Flow Direction and Seep Locations
Figure 3: Comparison of Carbon Isotherms for Heptachlor Epoxide, Two PAHs, and HFPO-
DA
Figure 4: Conceptual Process Flow Diagram of Primary Treatment Train and Solids Recovery
Process
LIST OF APPENDICES
Appendix A: Analytical Data for Groundwater & Seep Sources for the Engineering Design
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ACRONYMS AND ABBREVIATIONS
BCA Black Creek Aquifer
CO Consent Order
GAC granular activated carbon
GPM gallons per minute
GWTS groundwater treatment system
HDPE high density polyethylene
HFPO-DA hexafluoropropylene oxide-dimer acid
HRT hydraulic retention time
mg/L milligrams per liter
MTZ mass transfer zone
NCDEQ North Carolina Department of Environmental Quality
ND Non -detect
NPDES National Pollutant Discharge Elimination System
PAH polycyclic aromatic hydrocarbons
PFAS per- and polyfluoroalkyl substances
PFMOAA perfluoro- 1 -methoxyacetic acid
PMPA perfluoro-2-methoxypropanoic acid
STD standard
TSS total suspended solids
ug/L micrograms per liter
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1. INTRODUCTION AND BACKGROUND
This Engineering Report was prepared by Geosyntec Consultants of NC, P.C.
(Geosyntec) for the Chemours Company FC, LLC (Chemours) to provide a description
of the future treatment works to be installed for the collection and treatment of
groundwater and surface water from locations along the proposed groundwater remedy
alignment at the Chemours Fayetteville Works, North Carolina site (the Site). The
groundwater remedy includes a barrier wall, water extraction network, and treatment
system (Groundwater Treatment System or GWTS) is a requirement of the Addendum to
the Consent Order paragraph 12 (CO Addendum) amongst Chemours, the North Carolina
Department of Environmental Quality (NCDEQ), and Cape Fear River Watch entered by
the court on October 12, 2020.
The goal of the GWTS is to achieve a removal efficiency of 99%, as measured by
indicator parameters hexafluoropropylene oxide-dimer acid (HFPO-DA), perfluoro-2-
methoxypropanoic acid (PMPA), and perfluoro-1-methoxyacetic acid (PFMOAA). The
remedy is to commence operation by March 15, 2023 per paragraph 3(b) of the
Addendum to the CO. To meet this requirement, Chemours intends to complete
construction of the GWTS by April 1, 2022. Chemours will need to pump and treat the
water collected by the remedy to protect the barrier wall's structural integrity. The GWTS
therefore needs to be operational prior to the remedy's construction in June 2022.
This document provides the conceptual design and engineering assumptions for the
GWTS, in accordance with the National Pollutant Discharge Elimination System
(NPDES) permit application requirements. The permit application requires that
Chemours identify effluent characteristics of those parameters identified in the EPA
Application Form 2D New Manufacturing, Commercial, Mining, and Silvicultural
Operations That Have Not Yet Commenced Discharge of Process Wastewater (EPA Form
2D).
1.1 Site History and Overview
The Site is located on NC Highway 87, 15 miles southeast of the City of Fayetteville, and
south of the Bladen-Cumberland County line. The Site encompasses 2,177 acres of
relatively flat undeveloped open land and sloping woodland bounded on the east by the
Cape Fear River, on the west by NC Highway 87, and on the north and south by farmland.
The ground on which the Site is situated slopes East towards the Cape Fear River. The
proposed treatment facility is to be located on the southeastern portion of the Site just
north of the William O. Huske Lock & Dam.
E.I. du Pont de Nemours and Company (DuPont) purchased the property in parcels from
several families in 1970. The Site's first manufacturing area was constructed in the early
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1970s. Currently, the Site manufactures plastic sheeting, fluorochemicals, and
intermediates for plastics manufacturing. A former manufacturing area, which was sold
in 1992, produced nylon strapping and elastomeric tape.
DuPont sold its Butacite® and SentryGlas® manufacturing units to Kuraray America,
Inc. in June 2014; these are now a tenant operation. In July 2015, DuPont separated its
specialty chemicals business into a new publicly traded company named The Chemours
Company FC, LLC. With this separation, Chemours became the owner of the entire 2,177
acres of the Fayetteville Works along with the Fluoromonomers, Nafion® membranes,
and Polymer Processing Aid (PPA) manufacturing units. The polyvinyl fluoride (PVF)
resin manufacturing unit remained with DuPont as a tenant operation.
In addition to the manufacturing operations, Chemours operates two natural gas -fired
boilers and a biological wastewater treatment plant for the treatment of DuPont and
Kuraray process wastewater and sanitary wastewaters from DuPont, Kuraray, and
Chemours.
1.2 Process Overview
Groundwater at the Site currently flows east towards the Cape Fear River. The extraction
and conveyance portion of the treatment design proposes to capture the groundwater flow
via the installation of a network of groundwater extraction wells and to capture the
baseflow of seeps originating upgradient of the remedy and flows during rainfalls up to
0.5 inches in depth. The extracted groundwater and seeps water will then be collected and
conveyed to be treated by the GWTS which is proposed to be located in the southeast
corner of the Site. The proposed location is shown in Figure 1.
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Proposed
new GWTS
location
Legend
S Extraction well
- Planned groundwater remedy route
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Figure 1: Remedy Alignment and Proposed Groundwater Treatment System Location
The GWTS will be comprised of a series of chemical and physical separation steps.
Chemical oxidation and pH adjustment will first be employed to precipitate metals, such
as iron, to prevent downstream contamination or fouling of the granulated activated
carbon (GAC) media. The precipitated metals and other particles above an appropriate
control threshold will be removed via ultrafiltration membranes or some other suitable
separation technology. The filtered effluent will then be treated for per- and
polyfluoroalkyl substances (PFAS) by GAC adsorption. The reject from the filtration and
GAC systems will undergo dewatering through a thickening tank and filter press or
centrifugation, from which the sludge cake will be disposed of offsite and the press water
will be recycled to the influent of the thickening tanks. Periodic backwashing will extend
membrane and carbon media life, and the carbon will be removed and replaced based on
breakthrough monitoring of several three -vessel carbon trains in a lead -middle -lag
arrangement. Associated design elements such as pumps, piping, electrical,
instrumentation and control for interlocks, mechanical and civil/structural elements will
be finalized during the detailed design phase. This design concept may be optimized
based on ongoing benchtop studies and data acquisition.
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2. DESIGN BASIS
2.1 Aquifer Location
The ground on which the Site is situated slopes east from the facility towards the Cape
Fear River. The main groundwater aquifers therefore also flow towards the Cape Fear
River. Furthermore, there are four seeps that also contribute surface water flow to the
Cape Fear River, as identified in Figure 2.
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Proposed groundwater remedy alignment
Seep
Nearby tributary to river
General direction of groundwater flow
Site boundary
Figure 2. Groundwater Flow Direction and Seep Locations
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The groundwater originates from two main aquifers, known as the Black Creek Aquifer
(BCA) and the Surficial Aquifer. These two zones are separated by the Black Creek
Confining Unit along most of the length of the proposed groundwater remedy alignment,
and the BCA is underlain by the Upper Cape Fear Confining unit, which is a layer of
competent clay.
The groundwater daylights near the Cape Fear riverbank as various seeps. There are four
seeps (Seeps A through D), although only two of these are major hydraulic contributors
(A and B) which will require collection for treatment. The estimated hydraulic loading in
gallons per minute (gpm) from the two aquifers and four seeps, post remedy construction,
is shown in Table 1.
Table 1: Hydraulic Loading of Representative Groundwater and Seep Sources
Water Source
Approximate Flow Rate
0
Seeps Baseflow
161 gpm
*
Seeps Stormflow
108 gpm
°
Groundwater from Surficial Aquifer
150 gpm
Groundwater from Black Creek Aquifer
800 gpm
Total Flow
1,219 gpm
* Seeps stormflow represents maximum increase over baseflow averaged over 24-hour period.
0 Seeps baseflow and Shallow Groundwater may include some double counting. Seeps baseflow represents the 95th
percentile instantaneous flow from each of Seeps A and B at location representative of the remedy capture location.
Actual flows may vary from these model results due to variability in rainfall. The largest
rainfall effect is expected to be seen in the seeps stormflow parameter in Table 1; the cited
108 gpm value is the 24-hour average flow for a 0.5 inch storm event. The seeps' baseflow
quantity is also a conservative estimate (i.e. high -end). For this reason, the extraction
system and the GWTS will be designed to handle reasonable expected flow variations
and the GWTS currently has a planned capacity safety factor such that a maximum design
flow of 1,500 gpm has been selected.
2.2 Influent Water Quality
The source water to the GWTS will be the extracted groundwater and captured seep
water. The groundwater will be extracted from a series of approximately 60 extraction
wells installed along the length of the proposed groundwater remedy alignment. Water
will also be captured from seeps originating upgradient of the barrier wall (Seeps A and
B). Since the GWTS has not yet been installed, the influent water quality presented in
this report is from representative wells in the associated aquifers and the seeps. The
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currently available non-PFAS analytical data from the individual untreated groundwater
and seep sources, or their closest analogs, has been collected and is summarized in the
memorandum Chemours Fayetteville Works — Groundwater and Seeps Water Quality
Assessment (Geosyntec, 2021). Relevant analytical data for the engineering design,
including the PFAS data, is provided in Appendix A.
Groundwater sampling was completed at four representative groundwater wells and three
seep locations. The seep locations are shown relative to the site in Figure 2. The
groundwater wells are analogs for the various groundwater sources to be collected by the
new extraction network along the groundwater remedy alignment, as described in Table
2. Two of the seep locations (Seep A at Wall Point and Seep B at Wall Point) are analogs
for the seep baseflow and surface runoff that will be intercepted by the groundwater
remedy. The samples collected at the location Seep A minor tributary are not analogs of
seep water as the location was artificially disturbed prior to sample collection to introduce
sediment into the sample. The results from Seep A minor tributary were, however,
included in the engineering design as a safety factor.
Table 2: Representative Well and Seep Locations and Estimated Flowrates
Representative Water
Location Tag
Flowrate
(gpd)
Flowrate
(gpm)
Proportion
/0)
Black Creek Aquifer at North
EW-1
668,794
464
47%
Black Creek Aquifer at South
EW-3
428,198
297
30%
Surficial Aquifer at North
PIW-5S
104,760
73
7%
Surficial Aquifer at South
PIW-10S
75,773
53
5%
Seep A minor tributary*
SEEPA-TR-N
31,522
22
2%
Seep A at Wall Point
SEEP -A -WALL
50,501
35
4%
Seep B at Wall Point
SEEP-B-WALL
67,133
47
5%
* Samples were artificially disturbed at SEEP-A-TR-N prior to collection to introduce turbidity.
The dataset used for the GWTS design is inclusive of untreated water data collected
during sampling events from 2019 and 2020 and a series of 11 sampling events that
occurred during March and April 2021. PFAS compounds were specifically sampled for
on March 3, March 26 and April 28, 2021. Appendix A provides a detailed overview of
the average, maximum, and minimum concentrations of all untreated water parameters
sampled for treatment design. The water collected at these wells (EW-1, EW-3, PIW-5S
and PIW-10S) and two seep locations (SEEP -A -WALL and SEEP-B-WALL) is assumed
to be representative of the total groundwater and seep flow that will be extracted and
treated by the GWTS.
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In addition to PFAS analyses, a variety of supporting analytes such as total suspended
solids (TSS), and metals (such as aluminum and iron) were sampled as they were
considered key parameters of concern that would inform the pre-treatment system
upstream of the PFAS removal stage. Flow -weighted composite concentrations for each
parameter were developed for each of the groundwater and surface water groupings, as a
design aid for the development of the influent design basis. The average, minimum and
maximum mass loading of each untreated water parameter and Table 3+ compound was
estimated using the average, minimum, and maximum concentrations from the analytical
data and the flow rates in Table 1. Thus, the flow -weighted, mass -based composition for
the untreated water groundwater sources was estimated by summing the mass loadings
from PIW-5S, PIW-10S, EW-1, and EW-3. The flow -weighted average composition for
the seeps was estimated by summing the mass loadings from SEEP -A -WALL, SEEP-B-
WALL, and SEEP-A-TRN.
The projected concentrations in the combined influent to the GWTS were estimated from
the flow -weighted concentrations groundwater and surface water groupings. Upon
construction completion of the groundwater remedy, it is estimated that the total dry -
weather groundwater and surface water flows will be 950 gpm and 161 gpm, respectively.
The groundwater and surface water groupings were combined by flow -weighting the
average, minimum, and maximum concentrations using these estimated post -construction
flows. The design of the GWTS is based on the contaminant profile in Table 3.
Table 3: Influent Design Basis for the Groundwater Treatment System
Constituent
Units
Projected Concentrations
Influent Design
Basis
Avg.
Min.
Max.
Min.
Max.
HFPO Dimer
Acid
ug/L
12.2
8.22
18.9
4.11
28.3
PFMOAA
ug/L
64.3
17.5
192
8.73
288
PMPA
ug/L
13.2
8.38
22.5
4.19
33.8
Total table 3+
(20 compounds)
ug/L
139
54.9
352
27.4
528
Aluminum, total
mg/L
1.52
1.16
2.20
0.58
3.30
Bromide
mg/L
ND
ND
ND
ND
ND
Calcium, total
mg/L
4.07
3.74
4.55
1.87
6.82
Carbonate
Alkalinity
mg/L
ND
ND
ND
ND
ND
Chloride, total'
mg/L
8.30
4.85
11.6
2.42
17.4
Fluoride, total
mg/L
0.11
0.11
0.11
0.06
0.17
Hardness
mg/L
ND
ND
ND
ND
ND
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Constituent
Units
Projected Concentrations
Influent Design
Basis
Avg.
Min.
Max.
Min.
Max.
Iron, total
mg/L
4.86
2.28
8.56
1.14
12.8
Magnesium,
total
mg/L
2.37
2.27
2.53
1.13
3.80
Manganese,
total
mg/L
0.08
0.06
0.15
0.03
0.23
pH
Std units
6.61
6.50
6.80
6.5
8.5
Phosphate
mg/L
ND
ND
ND
ND
ND
Sulfate (as SO4)
mg/L
24.7
13.3
33.9
6.66
50.9
Total Dissolved
Solids
mg/L
78.5
66.8
93.3
33.4
140
Total Organic
Carbon
mg/L
1.11
0.57
2.01
0.29
3.01
TSS2
mg/L
59.2
38.4
120
19.2
180
SEEP -A -WALL and SEEP-B-WALL each had one observation above 30,000 milligrams per liter (mg/L) chloride.
Data has been excluded and can be considered an outlier for the basis of design.
2 Potentially 250 mg/L during peak storm events (see below). This also does not include the total suspended solids
(TSS) contribution from solids generated during pretreatment.
2.3 Groundwater and Seeps Outfall
The treated groundwater and seeps water will be discharged to the Chemours Fayetteville
Site Outfall 002 discharge line to the Cape Fear River. The average flow rate from the
Outfall 002 is 18.025 million gallons per day. The water quality assessment accounted
for the combination of loads from Outfalls 004 and 002. In addition, the water quality
assessment accounted for the mixing zone analysis that was conducted for Outfall 002
that documented a river dilution of 8:1 (Geosyntec, 2019).
2.4 Influent Untreated Water Quality - Comparison to Water Quality Criteria
The groundwater and seep data for non-PFAS compounds were compared to North
Carolina's surface water quality criteria. This screening -level exercise was conservative
as no treatment was assumed. Results are documented in a memorandum - Chemours
Fayetteville Works - Groundwater and Seeps Water Quality Assessment (Geosyntec,
2021). After flow -weighting the groundwater and seeps' concentrations, incorporating
the load from Outfall 002, and applying an 8:1 dilution from the Outfall 002 mixing zone,
heptachlor epoxide and polycyclic aromatic hydrocarbons (PAHs) warrant consideration
as additional pollutants targeted for removal by the GWTS.
Heptachlor epoxide was only detected in one well (PIW-5S) and one seep (SEEP -A -
WALL) at low levels. The PAH compounds were only detected at low levels in one (PIW-
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5S) of the six untreated groundwater and seep sources. As detailed in the Groundwater
and Seeps Water Quality Assessment (Geosyntec, 2021), Chemours will be resampling
these locations to confirm the presence of these compounds.
However, if these compounds are occasionally present in the influent to the GWTS it is
unlikely that they will pass -through the GWTS. Heptachlor epoxide is extremely well
adsorbed by activated carbon due to its size, double bonds, and the presence of chlorine
atoms in the structure. PAHs tend to have strong sorptive interactions with carbon due to
their hydrophobic nature and size. Activated carbon itself is composed largely of
graphene plates, and this molecular similarity strengthens the binding energies via t-7c
dispersive forces. A thorough review of the use of activated carbon (as well as other
adsorbents) for removal of PAHs from water can be found in Chemosphere 148 (2016),
336-353. A number of other literature sources are also available that include adsorption
equibria (i.e. isotherms), kinetics, and the combined effects in traditional packed bed
adsorbers which give rise to dynamic capacities for various PAHs on activated carbons.
Loading mg/g
TR0795
Sorption of Various Organic Compounds on Activated Carbon
- Weptech Ior epoxide
- Ben zo k} fl u ora nth en
- Benno; b jfl uo ra nthe the
HFPO-OA
100 -
10 -
1
a.nnm
C_0t
n. I
Concentration, ni /L
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Figure 3: Comparison of Carbon Isotherms for Heptachlor Epoxide, two PHAs, and
HFPO-DA. Data from "Carbon Adsorption Isotherms for Toxic Organics" (EPA-
600/8-80-023, April 1980).
The PFAS compounds this system is designed to treat adsorb to carbon more weakly than
PAHs, as shown in Figure 3. Additionally, they are present in the water at concentrations
roughly two orders of magnitude higher than the PAHs (and roughly four orders of
magnitude higher than the heptachlor epoxide) that may be present in the intake water.
As this treatment system will be run to prevent breakthrough of the three indicator PFAS,
it is expected that heptachlor epoxide and the PAHs will be readily sorbed by the GAC
and therefore are not expected to cause or contribute to exceedances of water quality
criteria in the Cape Fear River if present in the wastewater.
2.5 Pilot Studies
Pilot studies have been completed by vendors to verify the effectiveness of their proposed
pretreatment methods and confirm performance of their selected carbon media to remove
the required constituents and loadings from representative feed water. Tests were
performed using bulk water collected from the sources in Table 2, which was
proportionally blended based on collected flow contribution. The vendors were also
furnished influent water quality data for each source. These pilot studies are being used
to inform the efficacy of proposed full-scale treatment design, including pretreatment
dosing chemistry and residuals characterization (for solids separation and solids -handling
designs).
2.6 Pumping & Conveyance Design
Groundwater modeling remedy development presently indicates a total of approximately
50 new BCA and extraction wells and 10 surficial aquifer extraction wells will be required
to intercept groundwater. The combined maximum total flow rate produced from these
wells is expected to be approximately 950 gpm.
Each well pump is expected to extract approximately 5 to 30 gpm and will be sized to
have additional flow capacity for contingency. The extraction wells are currently planned
as high -density polyethylene (HDPE) construction below finished grade, whereas the
wellhead will be of polyvinyl chloride construction.
Each wellhead will then tee into their corresponding conveyance line (i.e., North or South
Force mains), constructed of HDPE. Approximately two thirds of the required extraction
wells will convey groundwater through the North Force main while the remaining third
is conveyed via the South Force main. The conveyance lines will be sized to
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accommodate the total collected flow of the extraction with added contingency to allow
for increased extraction rates if required. Extracted groundwater will be conveyed to a
surge tank prior to being treated by the GWTS.
The seep flow will be impounded at or near seep capture locations (impoundment storage)
to provide equalization storage during rainfall events and remove readily
settleable/suspended solids prior to being conveyed to a break tank and treated by the
GWTS.
The total maximum dry weather flow to the GWTS after the groundwater remedy is fully
operational, including seep flow, is estimated to be 1,111 gpm. Total flow over a 24-hour
period with rainfall is estimated to average 1,219 gpm (see Table 1). The design flow rate
for the GWTS was selected to be 1,500 gpm to allow for increased groundwater extraction
from the extraction wells and potential uncertainty in post -installation flow behavior from
the seeps.
At the break tank, the influents from the extracted groundwater and the seeps will be
combined. The effluent of the tank will then be drawn on demand by the GWTS. The
impoundment storage will be dredged periodically, and solids characterized and disposed
of at an appropriately designated facility.
3. PROPOSED TREATMENT DESIGN
3.1 Overall Narrative
Based on turnkey vendor proposals currently under consideration, the GWTS is assumed
to be comprised of the following series of treatment units:
1. Metals oxidation;
2. Ultrafiltration (UF) or similar solids separation technology;
3. Granular Activated Carbon (GAC) adsorption;
4. Solids Handling & Dewatering; and
5. Ancillary processes for backwashing and residuals handling.
The influent oxidation system will be designed to help ensure complete oxidation of
reduced iron species (or other dissolved metals), by means of pH adjustment and possible
addition of inorganic coagulant and/or flocculant. Following oxidation, flow will proceed
to the solids separation unit in which particle sizes above an appropriate control threshold
will be removed. The filtrate will then be pumped to the GAC adsorption process, which
will remove the PFAS and other contaminants from the water. Influent flow to the carbon
beds may be pH adjusted to improve treatment performance. The GAC effluent will
undergo further pH adjustment back to near -neutral conditions and then be discharged to
the Cape Fear River via the pipe that conveys existing flows from Outfall 002 to the river.
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The solids separation unit reject, solids separation unit cleaning, and GAC backwash
water will collect in one or more thickener tanks. The thickened solids will be dewatered
using a filter press or centrifuge. Sludge cake will be transferred into hoppers that will be
trucked off -site for disposal at a permitted waste disposal facility. The dewatering filtrate
will be returned to the head of the plant and blended with the influent downstream of the
oxidation tanks. A backwash water tank will store a limited volume of treated water to
supply GAC backwash, polymer dilution, and other process water requirements. A GAC
backwash waste tank will collect backwash water and bleed it back into the treatment
process downstream of the oxidation tanks. Process design considerations for each unit
operation are further described in Section 3.2.
Based on vendor experience, Chemours' current operational experience at Outfall 003
elsewhere at the facility, and outcomes of past treatability pilot studies, it is anticipated
that a treatment design consisting of these elements will successfully address treatment
requirements. In addition, Chemours is currently performing treatability studies based on
anticipated wastewater characteristics of the groundwater and seeps.
A conceptual process flow diagram (PFD) of the GWTS and the associated sludge
handling system is shown in Figure 4.
TR0795 17 June 2021

TR0795
Geosyntec
consultants
Georynt“Canud1onts ofNC, P.C.
NC L.IctiM, Nu; 4.. end G-295
Feed
a
■
Frac tank
Frac tank
Caustic
Chlorine
Coagulant
Anionic
polymer
Decant
Anionic polymer
OF
Vessel
OF
Vessel.
OF
Vessel
iJF
I _
Vessel jl�*
OF
Vessel
Cone
Bottom
Tank
H2SO4
pH to 3-5
Frac tank
Frac tank
CIP
Caustic
St35
12' diameter vessels
GAG
GAG
GAC
GAC
GAC
GAG
GAG
GAG
GAG
Caustic
pH to 6-9
OF Reject
Sludge
T
Cone
Bottom
Tank
Decant
Frac tan
Filtrate
Cationic polymer
Filter
Press
Solids
■
Soilds roll -off
Frac tank
4
To Outfall
Frac tank
To GAC BiW,
Rinse, Sluice
GAC
— Backwash
Out
GAC System
Solids handling
Pre- and post- treatment
Figure 4: Conceptual Process Flow Diagram of Primary Treatment Train and Solids Recovery Process System
18
June 2021

Geosyntee °
consultants
GrusymccCmisidimi<x ofNC. RC.
NC 1-i,oi Nu: C-3500 mt.' C-295
3.2 Individual Unit Operations
3.2.1 Metals Oxidation
One or more influent oxidation retention tanks will be selected to allow for a hydraulic
retention time (HRT) of 30 minutes at the design flow of 1,500 gpm. The HRT has been
selected to achieve the optimal pH range of 6.5 to 7.5 and allow for the oxidation and
coagulation of ferrous iron (Fe2+) to the less soluble ferric iron (Fe3+). Multiple tanks may
be configured in a duty, active -standby configuration, with the capability to take one or
more tanks offline for maintenance and still process the total plant flow of 1,500 gpm.
Upstream of the tanks, chemical augmentation via an inorganic coagulant, sodium
hydroxide, and sodium hypochlorite will be performed to adjust the pH, limit biofouling,
and promote metals coagulation in the retention tanks. pH adjustment chemicals (sodium
hydroxide and sulfuric acid) will be added to reach the target pH based on feedback from
one or more pH probes.
3.2.2 Filtration
Effluent from the oxidation process is pumped to the solids separation operation, via two
or more pumps in duty -standby configuration.
Ultrafiltration membranes or a similar solids separation process will be used to remove
fine solids and turbidity down an appropriate control threshold upstream of the GAC beds
to prevent fouling and extend runtimes between carbon backwashes or media
replacement. The currently proposed OF system will be comprised of parallel banks of
submerged membranes, provided as a prefabricated system, including the vessels,
influent, effluent and backwash manifolds, automatic open/close valves, and any other
ancillary equipment required.
The filtered effluent from the solids separation process will be directed to a pH adjustment
tank where sulfuric acid can be dosed to lower the pH to approximately 3.5 prior to being
transferred to the GAC system. This pH adjustment is expected to improve GAC
performance and extend service life. The reject and backwash from the solids separation
process will routed to the sludge handling system to be dewatered prior to disposal.
3.2.3 Granular Activated Carbon Adsorption
PFAS removal will be accomplished using GAC adsorption. Filtered effluent will be
pumped from the pH adjustment tank to the GAC system and will enter three GAC
adsorption trains, each designed to treat one third of the design flow (500 gpm). Each
vessel will be configured as a down -flow process where water enters the top of the
adsorber and exits through the bottom. In this configuration, adsorption of contaminants
TR0795 19 June 2021

Geosyntee °
consultants
GrusymccCmisidimi<x ofNC. RC.
NC 1-i,oi Nu: C-35flO onJ C-295
(i.e., PFAS) will begin in the upper portion of the GAC bed. The mass transfer zone
(MTZ) will move from the top of the bed downwards as each portion of the bed becomes
saturated with the contaminants. Eventually, breakthrough will occur wherein the effluent
of the tower contains the contaminant. Multiple carbon adsorbers will be arranged in
series to capture the breakthrough.
A three -column, lead/middle/lag, configuration per train is proposed for the GWTS. It is
assumed that complete saturation of the lead column will occur prior to the initiation of a
carbon changeout. During routine operation the lead column will act as the primary
contaminant remover. The MTZ will travel from the top of the bed to the bottom until
breakthrough of a contaminant of concern occurs. The spent GAC in the lead column will
then be replaced with new GAC and the previous lead column will be placed in the lag
column position. The expired GAC will be shipped offsite for disposal and if appropriate,
regeneration of the carbon. The previous middle column will then become the lead
column and the previous lag/third position column will become the second position
column. It is expected that this operating the system in this manner will result in
significant operations and maintenance savings without compromising removal
efficiencies.
Preliminary sizing for this application indicates that a series of 12-foot diameter vessels
that can hold 20,000 pounds of carbon each will provide for the required hydraulic
loading rate and Empty Bed Contact Time for PFAS removal.
Effluent from the GAC trains will be transferred to a storage tank, where caustic will be
dosed to the effluent upstream of the tank to adjust the pH back to neutral prior to
discharge. This tank is sized to provide an appropriate retention time for the pH
adjustment step.
The used backwash water will be collected and transferred to the thickening process for
dewatering and disposal.
3.2.4 Solids Handling and Dewatering
The thickened sludge from the bottom of the thickening operation will be pumped to a
filter press or similar technology for dewatering. The supernatant decanted from the top
of the sludge thickening operation will be recycled to the influent of the initial chemical
oxidation step for reprocessing.
3.3 Operability and Maintenance Considerations
Process equipment has been selected from established vendors who maintain available
inventory of critical spare parts, and the turnkey service provider should also have access
to spares inventory based on duplication of unit operations in their commercial fleet. The
TR0795 20 June 2021

Geosyntec °
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GrusymccCmisidimi<x ofNC. RC.
NC 1-i,oi Nu: C-35flO onJ C-295
modular nature of the process train means that it is readily expanded or modified to adjust
to future changes in process conditions or treatment requirements.
3.4 Process Monitoring
The treatment process will be instrumented to monitor process performance consistent
with industry best practices. Process data will be recorded in a remotely accessible
database with an extended storage capacity and uninterruptible power supply.
Regulatory compliance will be maintained by means of routine sampling and analytical
testing of the untreated influent and treated water discharge points. Once a week, the
influent to each train and the effluent of each vessel will be sampled and tested at the Site
internal laboratory. Percent breakthrough is calculated for each PFAS indicator species.
First PMPA, and then PFMOAA, breakthrough values are used to determine when a bed
replacement is triggered. Generally once breakthrough begins to be observed in the
middle vessel, the lead vessel's media is changed out. The former lead vessel, filled with
new media, then becomes the lag vessel, former lag becomes the middle vessel, and
former middle vessel becomes the new lead vessel.
4. SUMMARY
In summary, the groundwater and seep flow associated with the proposed groundwater
remedy will be collected and treated (by physical/chemical precipitation, filtration and
carbon adsorption). It is anticipated that the environmental impacts associated with the
groundwater and seep water will be significantly diminished and the treated water will
exhibit a significant reduction in PFAS target compounds, total suspended solids and
dissolved metals. PAHs, and heptachlor epoxide will also be treated if present. This will
reduce the impact of these pollutants in the Cape Fear River.
5. REFERENCES
Geosyntec, 2019. Mixing Zone Report, Addendum, Chemours Fayetteville Works
Outfall 002. October 2019.
Geosyntec, 2021. Memorandum to Chemours. Chemours Fayetteville Works —
Groundwater and Seeps Water Quality Assessment. June 10, 2021.
TR0795 21 June 2021

Geosyntee °
consultants
GrusymccCmisidimi<x ofNC. RC.
NC 1-i,oi Nu: C-35flO onJ C-295
APPENDIX A
Analytical Data for Groundwater & Seep Sources
for the Engineering Design
TR0795 June 2021

June 2021
Table Al: EW-1 Table 3+ Compound Summary
Location:
EW-1
Table 3+ Compounds
# of Results
# of Non -Detects
Average (ug/L)
Min (ug/L)
Max (ug/L)
Range (ug/L)
Std Dev (ug/L)
EVE Acid
9
9
ND
ND
ND
ND
ND
Hfpo Dimer Acid
6
0
3.30
1.60
6.90
5.30
1.94
Hydro -EVE Acid
9
8
0.05
0.05
0.05
0.00
ND
Hydrolyzed PSDA
9
3
0.48
0.02
1.60
1.58
0.69
Hydro -PS Acid
10
9
0.03
0.03
0.03
0.00
ND
NVHOS
8
0
0.26
0.11
0.59
0.48
0.20
PEPA
10
0
0.48
0.06
1.70
1.65
0.61
PES
9
8
0.01
0.01
0.01
0.00
ND
PFECA B
9
9
ND
ND
ND
ND
ND
PFECA-G
10
10
ND
ND
ND
ND
ND
PFMOAA
10
0
34.20
13.00
74.00
61.00
24.13
PFO2HxA
10
0
10.64
2.90
32.00
29.10
10.08
PFO3OA
10
0
1.16
0.10
4.20
4.10
1.53
PFO4DA
10
8
1.04
0.08
2.00
1.92
1.36
PFO5DA
10
10
ND
ND
ND
ND
ND
PMPA
10
0
2.79
1.10
7.50
6.40
2.27
PS Acid
10
10
ND
ND
ND
ND
ND
R-EVE
9
3
0.13
0.04
0.35
0.32
0.13
R-PSDA
9
3
0.17
0.04
0.47
0.43
0.17
R-PSDCA
9
9
ND
ND
ND
ND
ND
Table A2: EW-1 Treatment Parameter Summary
Treatment Parameter
# of Results
# of Non -Detects
Average (mg/L)
Min (mg/L)
Max (mg/L)
Range (mg/L)
Std Dev (mg/L)
Aluminum
3
1
0.06
0.04
0.09
0.05
0.04
Bromide
12
12
ND
ND
ND
ND
ND
Calcium
3
0
2.70
2.60
2.80
0.20
0.10
Carbonate Alkalinity
0
0
--
--
--
--
--
Chloride
12
0
7.19
6.30
10.00
3.70
1.00
Fluoride
3
3
ND
ND
ND
ND
ND
Hardness
0
0
--
--
--
--
--
Iron
24
0
1.73
1.40
2.10
0.70
0.23
Magnesium
3
0
1.37
1.30
1.50
0.20
0.12
Manganese
23
0
0.02
0.02
0.03
0.01
0.00
pH
2
0
6.90
--
--
--
0.14
Phosphate
1
1
ND
ND
ND
ND
ND
Sulfate
12
0
15.08
14.00
17.00
3.00
1.00
Total Dissolved Solids
3
0
64.00
51.00
78.00
27.00
13.53
Total Organic Carbon
12
12
ND
ND
ND
ND
ND
Total Suspended Solids
3
0
8.80
5.90
13.00
7.10
3.72
*pH expressed in standard units
Legend:
ug/L = micrograms per liter
mg/L = milligrams per liter
Min = minimum
Max = maximum
Range = difference between max and min
Std Dev = standard deviation
Engineering Report - Groundwater and Seeps Treatment System
Prepared by: Geosyntec Consultants of NC, P.C.

June 2021
Table A3: EW-3 Table 3+ Compound Summary
Location:
EW-3
Table 3+ Compounds
# of Results
# of Non -Detects
Average (ug/L)
Min (ug/L)
Max (ug/L)
Range (ug/L)
Std Dev (ug/L)
EVE Acid
15
12
0.097
0.095
0.1
0.005
0.002645751
Hfpo Dimer Acid
10
0
13.03
9.30
16.00
6.70
2.15
Hydro -EVE Acid
15
0
0.75
0.42
1.10
0.68
0.20
Hydrolyzed PSDA
15
0
4.25
1.50
6.50
5.00
1.85
Hydro -PS Acid
15
0
0.51
0.16
0.98
0.82
0.36
NVHOS
13
0
1.52
0.43
4.80
4.37
1.36
PEPA
15
0
2.85
1.80
4.90
3.10
0.77
PES
15
11
0.00
0.00
0.01
0.00
0.00
PFECA B
15
15
ND
ND
ND
ND
ND
PFECA-G
15
15
ND
ND
ND
ND
ND
PFMOAA
15
0
132.13
27.00
470.00
443.00
129.07
PFO2HxA
15
0
32.53
14.00
91.00
77.00
20.87
PFO3OA
15
0
14.77
5.20
43.00
37.80
11.94
PFO4DA
15
0
6.76
1.20
20.00
18.80
6.66
PFOSDA
15
6
0.91
0.01
2.40
2.39
0.77
PMPA
15
0
8.41
5.70
12.00
6.30
1.78
PS Acid
15
8
0.42
0.23
0.56
0.33
0.12
R-EVE
15
2
0.73
0.17
1.20
1.03
0.33
R-PSDA
15
0
1.21
0.65
1.70
1.05
0.33
R-PSDCA
15
3
0.04
0.01
0.10
0.09
0.03
Table A4: EW-3 Treatment Parameter Summary
Treatment Parameter
# of Results
# of Non -Detects
Average (mg/L)
Min (mg/L)
Max (mg/L)
Range (mg/L)
Std Dev (mg/L)
Aluminum
3
0
0.75
0.41
1.40
0.99
0.56
Bromide
22
22
ND
ND
ND
ND
ND
Calcium
3
0
8.43
7.70
9.30
1.60
0.81
Carbonate Alkalinity
0
0
--
--
--
--
--
Chloride
22
0
12.42
3.00
16.00
13.00
2.67
Fluoride
4
3
0.32
0.32
0.32
--
--
Hardness
0
0
--
--
--
--
--
Iron
44
0
9.37
2.60
14.00
11.40
3.10
Magnesium
3
0
5.10
4.80
5.40
0.60
0.30
Manganese
43
0
0.20
0.16
0.25
0.09
0.02
PH
3
0
6.83
--
--
--
0.29
Phosphate
1
1
ND
ND
ND
ND
ND
Sulfate
22
0
59.95
14.00
72.00
58.00
12.44
Total Dissolved Solids
4
1
123.33
120.00
130.00
10.00
5.77
Total Organic Carbon
22
16
0.74
0.50
0.98
0.48
0.20
Total Suspended Solids
4
0
31.08
3.30
87.00
83.70
37.92
*pH expressed in standard units
Legend:
ug/L = micrograms per liter
mg/L = milligrams per liter
Min = minimum
Max = maximum
Range = difference between max and min
Std Dev = standard deviation
Engineering Report - Groundwater and Seeps Treatment System
Prepared by: Geosyntec Consultants of NC, P.C.

June 2021
Table A5: PIW-10S Table 3+ Compound Summary
Location:
PIW-10S
Table 3+ Compounds
# of Results
# of Non -Detects
Average (ug/L)
Min (ug/L)
Max (ug/L)
Range (ug/L)
Std Dev (ug/L)
EVE Acid
7
7
ND
ND
ND
ND
ND
Hfpo Dimer Acid
6
0
3.23
2.80
3.90
1.10
0.45
Hydro -EVE Acid
7
1
0.01
0.01
0.01
0.00
0.00
Hydrolyzed PSDA
7
7
ND
ND
ND
ND
ND
Hydro -PS Acid
7
0
0.11
0.09
0.15
0.06
0.02
NVHOS
6
1
0.03
0.02
0.04
0.01
0.01
PEPA
7
0
1.69
1.50
2.10
0.60
0.23
PES
7
7
ND
ND
ND
ND
ND
PFECA B
7
7
ND
ND
ND
ND
ND
PFECA-G
7
7
ND
ND
ND
ND
ND
PFMOAA
7
0
2.99
1.50
4.70
3.20
1.14
PFO2HxA
7
0
3.70
2.40
5.40
3.00
1.03
PFO3OA
7
0
0.70
0.45
0.99
0.54
0.20
PFO4DA
7
0
0.26
0.16
0.37
0.21
0.08
PFOSDA
7
2
0.02
0.01
0.03
0.02
0.01
PMPA
7
0
4.91
4.00
5.70
1.70
0.71
PS Acid
7
7
ND
ND
ND
ND
ND
R-EVE
7
0
0.15
0.09
0.20
0.11
0.04
R-PSDA
7
0
0.31
0.19
0.42
0.23
0.10
R-PSDCA
7
7
ND
ND
ND
ND
ND
Table A6: PIW-10S Treatment Parameter Summary
Treatment Parameter
# of Results
# of Non -Detects
Average (mg/L)
Min (mg/L)
Max (mg/L)
Range (mg/L)
Std Dev (mg/L)
Aluminum
4
0
0.84
0.62
1.20
0.58
0.28
Bromide
12
12
ND
ND
ND
ND
ND
Calcium
4
0
0.44
0.43
0.46
0.03
0.02
Carbonate Alkalinity
0
0
--
--
--
--
--
Chloride
12
0
4.13
3.10
5.50
2.40
0.66
Fluoride
3
3
ND
ND
ND
ND
ND
Hardness
0
0
--
--
--
--
--
Iron
24
13
0.52
0.04
2.60
2.56
0.78
Magnesium
4
0
0.60
0.58
0.61
0.03
0.01
Manganese
24
0
0.01
0.01
0.01
0.00
0.00
pH
3
0
6.77
--
--
--
0.25
Phosphate
0
0
--
0.00
0.00
--
--
Sulfate
12
0
9.94
9.00
11.00
2.00
0.67
Total Dissolved Solids
3
0
30.67
27.00
33.00
6.00
3.21
Total Organic Carbon
12
3
0.85
0.67
1.10
0.43
0.15
Total Suspended Solids
3
0
9.63
3.90
19.00
15.10
8.18
*pH expressed in standard units
Legend:
ug/L = micrograms per liter
mg/L = milligrams per liter
Min = minimum
Max = maximum
Range = difference between max and min
Std Dev = standard deviation
Engineering Report - Groundwater and Seeps Treatment System
Prepared by: Geosyntec Consultants of NC, P.C.

June 2021
Table A7: PIW-5S Table 3+ Compound Summary
Location:
PIW-5S
Table 3+ Compounds
# of Results
# of Non -Detects
Average (ug/L)
Min (ug/L)
Max (ug/L)
Range (ug/L)
Std Dev (ug/L)
EVE Acid
6
0
0.986666667
0.57
1.8
1.23
0.478567306
Hfpo Dimer Acid
5
0
33.80
25.00
41.00
16.00
5.97
Hydro -EVE Acid
6
0
1.55
0.82
2.00
1.18
0.40
Hydrolyzed PSDA
6
0
15.67
5.00
28.00
23.00
8.26
Hydro -PS Acid
6
0
1.25
0.58
1.40
0.82
0.33
NVHOS
5
0
0.70
0.65
0.77
0.12
0.04
PEPA
6
0
26.00
17.00
44.00
27.00
10.16
PES
6
6
ND
ND
ND
ND
ND
PFECA B
6
6
ND
ND
ND
ND
ND
PFECA-G
6
6
ND
ND
ND
ND
ND
PFMOAA
6
0
38.00
31.00
61.00
30.00
11.42
PFO2HxA
6
0
31.17
27.00
38.00
11.00
4.07
PFO3OA
6
0
8.58
7.50
10.00
2.50
0.97
PFO4DA
6
0
7.05
4.70
8.70
4.00
1.34
PFOSDA
6
0
5.23
1.90
6.60
4.70
1.76
PMPA
6
0
60.67
39.00
100.00
61.00
23.53
PS Acid
6
0
2.32
1.30
4.30
3.00
1.13
R-EVE
6
0
2.42
1.90
3.00
1.10
0.42
R-PSDA
6
0
3.70
2.90
4.70
1.80
0.63
R-PSDCA
6
0
0.05
0.04
0.07
0.03
0.01
Table A8: PIW-5S Treatment Parameter Summary
Treatment Parameter
# of Results
# of Non -Detects
Average (mg/L)
Min (mg/L)
Max (mg/L)
Range (mg/L)
Std Dev (mg/L)
Aluminum
2
0
0.91
0.86
0.96
0.10
0.07
Bromide
11
11
ND
ND
ND
ND
ND
Calcium
2
0
1.95
1.90
2.00
0.10
0.07
Carbonate Alkalinity
0
0
--
--
--
--
--
Chloride
11
0
5.80
5.40
6.30
0.90
0.28
Fluoride
2
2
ND
ND
ND
ND
ND
Hardness
0
0
--
--
--
--
--
Iron
22
0
0.79
0.04
12.00
11.96
2.52
Magnesium
2
0
0.82
0.79
0.84
0.05
0.04
Manganese
22
0
0.02
0.02
0.03
0.01
0.00
pH
2
0
6.75
--
--
--
0.35
Phosphate
0
0
--
0.00
0.00
--
--
Sulfate
11
0
22.36
20.00
24.00
4.00
1.63
Total Dissolved Solids
2
0
51.00
46.00
56.00
10.00
7.07
Total Organic Carbon
11
1
0.90
0.52
1.10
0.58
0.20
Total Suspended Solids
2
0
2.45
2.00
2.90
0.90
0.64
*pH expressed in standard units
Legend:
ug/L = micrograms per liter
mg/L = milligrams per liter
Min = minimum
Max = maximum
Range = difference between max and min
Std Dev = standard deviation
Engineering Report - Groundwater and Seeps Treatment System
Prepared by: Geosyntec Consultants of NC, P.C.

June 2021
Table A9: SEEPA-TR-N Table 3+ Compound Summary
Location: SEEPA-TR-N
Table 3+ Compounds
# of Results
# of Non -Detects
Average (ug/L)
Min (ug/L)
Max (ug/L)
Range (ug/L)
Std Dev (ug/L)
EVE Acid
7
7
ND
ND
ND
ND
ND
Hfpo Dimer Acid
4
0
12.85
8.40
19.00
10.60
4.51
Hydro -EVE Acid
7
2
0.08
0.06
0.10
0.04
0.02
Hydrolyzed PSDA
7
4
0.05
0.03
0.08
0.05
0.03
Hydro -PS Acid
7
2
0.28
0.24
0.33
0.09
0.04
NVHOS
6
2
0.09
0.07
0.12
0.05
0.03
PEPA
7
2
4.52
2.90
6.80
3.90
1.68
PES
7
7
ND
ND
ND
ND
ND
PFECA B
7
7
ND
ND
ND
ND
ND
PFECA-G
7
7
ND
ND
ND
ND
ND
PFMOAA
7
2
6.20
5.00
7.90
2.90
1.16
PFO2HxA
7
2
12.54
9.70
16.00
6.30
2.49
PFO3OA
7
2
2.12
1.70
2.80
1.10
0.43
PFO4DA
7
2
1.44
1.20
1.80
0.60
0.25
PFO5DA
7
2
0.35
0.32
0.38
0.06
0.02
PMPA
7
2
13.02
9.10
17.00
7.90
3.36
PS Acid
7
7
ND
ND
ND
ND
ND
R-EVE
7
2
0.50
0.26
0.89
0.63
0.26
R-PSDA
7
2
0.96
0.48
1.60
1.12
0.47
R-PSDCA
7
4
0.01
0.00
0.01
0.00
0.00
Table A10: SEEPA-TR-N Treatment Parameter Summary
Treatment Parameter
# of Results
# of Non -Detects
Average (mg/L)
Min (mg/L)
Max (mg/L)
Range (mg/L)
Std Dev (mg/L)
Aluminum
2
0
14.14
0.27
28.00
27.73
19.61
Bromide
11
10
0.27
0.27
0.27
--
--
Calcium
2
0
1.30
1.00
1.60
0.60
0.42
Carbonate Alkalinity
0
0
--
--
--
--
--
Chloride
11
0
4.16
3.50
5.40
1.90
0.54
Fluoride
2
2
ND
ND
ND
ND
ND
Hardness
0
0
--
--
--
--
--
Iron
22
0
13.90
0.74
44.00
43.26
14.73
Magnesium
2
0
1.46
0.82
2.10
1.28
0.91
Manganese
22
0
0.17
0.05
0.55
0.50
0.12
pH
2
0
6.75
--
--
--
0.35
Phosphate
0
0
--
0.00
0.00
--
--
Sulfate
11
0
10.73
10.00
12.00
2.00
0.79
Total Dissolved Solids
2
0
106.00
42.00
170.00
128.00
90.51
Total Organic Carbon
11
0
12.88
5.30
24.00
18.70
5.74
Total Suspended Solids
2
0
1100.00
1100.00
1100.00
--
0.00
*pH expressed in standard units
Legend:
ug/L = micrograms per liter
mg/L = milligrams per liter
Min = minimum
Max = maximum
Range = difference between max and min
Std Dev = standard deviation
Engineering Report - Groundwater and Seeps Treatment System
Prepared by: Geosyntec Consultants of NC, P.C.

June 2021
Table All: SEEPA-WALL Table 3+ Compound Summary
Location: SEEPA-WALL
Table 3+ Compounds
# of Results
# of Non -Detects
Average (ug/L)
Min (ug/L)
Max (ug/L)
Range (ug/L)
Std Dev (ug/L)
EVE Acid
24
0
1.219166667
0.14
9.1
8.96
1.728462289
Hfpo Dimer Acid
11
0
28.36
19.00
41.00
22.00
5.94
Hydro -EVE Acid
24
0
1.60
0.14
3.50
3.36
0.72
Hydrolyzed PSDA
24
0
24.05
3.30
72.00
68.70
16.10
Hydro -PS Acid
29
3
1.35
0.01
3.50
3.49
0.57
NVHOS
23
0
1.03
0.23
1.70
1.47
0.44
PEPA
28
0
11.75
6.90
22.00
15.10
4.75
PES
24
24
ND
ND
ND
ND
ND
PFECA B
24
24
ND
ND
ND
ND
ND
PFECA-G
29
29
ND
ND
ND
ND
ND
PFMOAA
29
0
70.93
15.00
130.00
115.00
41.13
PFO2HxA
29
0
35.38
18.00
55.00
37.00
11.30
PFO3OA
29
0
11.44
4.40
18.00
13.60
4.16
PFO4DA
29
0
6.91
1.40
11.00
9.60
2.28
PFO5DA
29
1
4.47
0.25
7.10
6.85
1.54
PMPA
28
0
27.25
17.00
46.00
29.00
7.94
PS Acid
29
2
4.56
0.02
31.00
30.98
5.92
R-EVE
24
0
1.36
0.80
3.60
2.80
0.53
R-PSDA
24
0
2.47
0.32
8.30
7.98
1.42
R-PSDCA
24
5
0.06
0.02
0.12
0.10
0.02
Table Al2: SEEPA-WALL Treatment Parameter Summary
Treatment Parameter
# of Results
# of Non -Detects
Average (mg/L)
Min (mg/L)
Max (mg/L)
Range (mg/L)
Std Dev (mg/L)
Aluminum
7
0
3.48
0.11
14.00
13.89
4.93
Bromide
12
12
ND
ND
ND
ND
ND
Calcium
7
0
3.14
1.31
6.40
5.09
2.24
Carbonate Alkalinity
5
5
ND
--
--
--
ND
Chloride
18
0
5.56
4.00
12.20
8.20
2.07
Fluoride
3
2
0.41
0.41
0.41
--
--
Hardness
0
0
--
--
--
--
--
Iron
27
0
1.63
0.07
21.40
21.33
4.10
Magnesium
7
0
0.89
0.51
1.50
0.99
0.36
Manganese
27
0
0.05
0.02
0.42
0.40
0.08
pH
3
0
6.77
--
--
--
0.25
Phosphate
5
4
1.00
1.00
1.00
--
--
Sulfate
16
0
14.88
8.60
30.30
21.70
5.96
Total Dissolved Solids
7
0
62.64
39.50
113.00
73.50
26.15
Total Organic Carbon
16
0
2.98
0.58
10.40
9.82
2.31
Total Suspended Solids
9
0
124.26
4.70
712.00
707.30
223.19
*pH expressed in standard units
Legend:
ug/L = micrograms per liter
mg/L = milligrams per liter
Min = minimum
Max = maximum
Range = difference between max and min
Std Dev = standard deviation
Engineering Report - Groundwater and Seeps Treatment System
Prepared by: Geosyntec Consultants of NC, P.C.

June 2021
Table A13: SEEPB-WALL Table 3+ Compound Summary
Location: SEEPB-WALL
Table 3+ Compounds
# of Results
# of Non -Detects
Average (ug/L)
Min (ug/L)
Max (ug/L)
Range (ug/L)
Std Dev (ug/L)
EVE Acid
29
0
8.624137931
1.4
46
44.6
11.3600382
Hfpo Dimer Acid
17
0
37.47
25.00
85.00
60.00
18.93
Hydro -EVE Acid
29
0
3.30
0.85
11.00
10.15
2.77
Hydrolyzed PSDA
29
0
43.93
21.00
120.00
99.00
22.31
Hydro -PS Acid
33
2
1.63
0.49
4.70
4.21
1.32
NVHOS
28
0
3.57
1.80
8.50
6.70
1.88
PEPA
31
0
22.13
12.00
50.00
38.00
11.69
PES
29
25
0.07
0.01
0.21
0.20
0.10
PFECA B
29
27
0.11
0.05
0.17
0.12
0.09
PFECA-G
33
31
0.11
0.00
0.21
0.21
0.15
PFMOAA
33
0
118.08
4.80
200.00
195.20
80.31
PFO2HxA
33
0
34.76
11.00
50.00
39.00
13.64
PFO3OA
33
0
7.20
2.50
12.00
9.50
2.80
PFO4DA
33
0
1.95
0.79
7.70
6.91
1.20
PFO5DA
33
5
0.72
0.13
1.90
1.77
0.62
PMPA
31
0
47.19
32.00
87.00
55.00
17.18
PS Acid
33
1
7.56
0.04
31.00
30.96
8.97
R-EVE
29
0
4.38
2.00
13.00
11.00
3.45
R-PSDA
29
0
5.81
2.50
16.00
13.50
3.64
R-PSDCA
29
2
0.11
0.05
0.38
0.33
0.10
Table A14: SEEPB-WALL Treatment Parameter Summary
Treatment Parameter
# of Results
# of Non -Detects
Average (mg/L)
Min (mg/L)
Max (mg/L)
Range (mg/L)
Std Dev (mg/L)
Aluminum
6
0
0.80
0.39
1.45
1.06
0.46
Bromide
12
12
ND
ND
ND
ND
ND
Calcium
6
0
0.96
0.69
1.58
0.89
0.32
Carbonate Alkalinity
4
4
ND
--
--
--
ND
Chloride
20
0
7.67
5.00
16.20
11.20
2.97
Fluoride
3
3
ND
ND
ND
ND
ND
Hardness
0
0
--
--
--
--
--
Iron
26
0
0.85
0.37
3.75
3.38
0.68
Magnesium
6
0
0.82
0.67
1.31
0.64
0.25
Manganese
26
0
0.03
0.02
0.41
0.40
0.08
pH
3
0
6.67
--
--
--
0.29
Phosphate
4
4
ND
ND
ND
ND
ND
Sulfate
15
0
10.70
7.00
24.40
17.40
4.70
Total Dissolved Solids
6
0
46.33
26.00
74.00
48.00
15.64
Total Organic Carbon
15
0
3.92
2.60
5.50
2.90
0.87
Total Suspended Solids
10
0
93.60
11.00
300.00
289.00
113.50
*pH expressed in standard units
Legend:
ug/L = micrograms per liter
mg/L = milligrams per liter
Min = minimum
Max = maximum
Range = difference between max and min
Std Dev = standard deviation
Engineering Report - Groundwater and Seeps Treatment System
Prepared by: Geosyntec Consultants of NC, P.C.

Attachment A.6 - Engineering Alternatives
Analysis — Treatment of Groundwater and
Upgradient Seeps Water

Geosyntecl>
consultants
Geosyntec Consultants of NC, P.C.
NC License No.: C-3500 and C-295
ENGINEERING ALTERNATIVES
ANALYSIS (EAA) -TREATMENT OF
GROUNDWATER AND UPGRADIENT
SEEPS WATER
Prepared for
The Chemours Company FC, LLC
1007 Market Street
PO Box 2047
Wilmington, DE 19899
Prepared by
Geosyntec Consultants of NC, P.C.
2501 Blue Ridge Road, Suite 430
Raleigh, NC 27607
Geosyntec Project Number TR0795
June 2021

Geosyntec °
consultants
GrusymccCmisidimi<x ofNC. RC.
NC 1-i,oi Nu: C-35flO onJ C-295
Applicant's Information:
Applicant Name: The Chemours Company FC, LLC
Facility Name: Fayetteville Works
Facility Mailing Address: 22828 NC Highway 87 W, Fayetteville NC 28306
County: Bladen
Phone Number: [phone]
Preparer's Information:
EAA Preparer: Geosyntec Consultants of NC, PC
Mailing Address: Atrium at Blue Ridge, 2501 Blue Ridge Road, Suite 430, Raleigh, NC
27607
Phone Number: [phone]
Contact Person: Adrienne Nemura, P.E.(MI, NC, OH)
TR0795 ii June 2021

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consultants
GrusymccCmisidimi<x ofNC. RC.
NC 1-i,oi Nu: C-35flO onJ C-295
TABLE OF CONTENTS
1. SITE HISTORY AND BACKGROUND 1
2. PROJECT SUMMARY 4
3. STEP 1 — ALLOWABILITY OF PROPOSED DISCHARGE 5
3.1 Analysis of Allowable Discharge Criteria 5
3.1.1 Applicability of the Local Government Review 5
3.1.2 EAA Guidance on Potential Restrictions 5
4. STEP 2: TREATMENT SYSTEM FLOW PROJECTION 10
4.1 Geological Descriptions 10
4.2 Extracted Groundwater Flow Estimate 12
4.3 Captured Seep Water Flow Estimate 12
4.4 Combined Flow Estimate 13
4.5 Pumping and Conveyance Design 16
5. STEP 3 ALTERNATIVES 16
5.1 Technologically Feasible Discharge Alternatives 17
5.1.1 Connection to Existing Public Treatment Plant 17
5.1.2 Wastewater Reuse 17
5.1.3 Direct Discharge 18
6. STEP 4 ECONOMICS 21
6.1 Economic Feasibility of Alternatives 21
6.1.1 PVCA Calculation Method 22
6.1.2 PVCA Summary 22
7. CONCLUSION AND PATH FORWARD 23
8. REFERENCES 24
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GrusymccCmisidimi<x ofNC. RC.
NC 1-i,oi Nu: C-35flO onJ C-295
LIST OF TABLES
Table 1: Hydraulic Loading of Representative Groundwater and Seep Sources
Table 2: Present Value Cost Analysis Summary Table
LIST OF FIGURES
Figure 1: Site Location Map
Figure 2: Remedy Alignment & Proposed Groundwater Treatment System Location
Figure 3: Cape Fear River Classification
Figure 4: High Resolution Cross Section with Interpreted Geology
Figure 5: Numerical Modeling Simulated Groundwater Levels
Figure 6: Seep Flume and Proposed Capture Locations
Figure 7: Conceptual Process Flow Diagram of Primary Treatment Process and Solids
Recovery Process
LIST OF APPENDICES
Appendix A: PWC Refusal to Accept Treated Wastewater
Appendix B: Cost Estimates
TR0795 iv June 2021

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NC 1-i,oi Nu: C-35flO onJ C-295
ACRONYMS AND ABBREVIATIONS
7Q10 seven-day, 10-year average low flow
BCA Black Creek Aquifer
cfs cubic feet per second
CO Consent Order
DWR Division of Water Resources
EAA Engineering Alternatives Analysis
ECOS Environmental Conservation Online System
EPA U.S. Environmental Protection Agency
GAC Granular Activated Carbon
gpm gallons per minute
GWTS Groundwater Treatment System
HDPE high density polyethylene
HFPO-DA hexafluoropropylene oxide-dimer acid
IPaC Information from the Planning and Consultation
NCDEQ North Carolina Department of Environmental Quality
NPDES National Pollutant Discharge Elimination System
PFAS per- and polyfluoroalkyl substances
PFD process flow diagram
PFMOAA perfluoro- 1 -methoxyacetic acid
PMPA perfluoro-2-methoxypropanoic acid
POTW Publicly Owned Treatment Works
TMDL Total Maximum Daily Load
WRF Water Reclamation Facility
WWTP wastewater treatment plant
TR0795 v June 2021

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consultants
Ct symcc[:uueulhm ix% of NI:. RC.
NC I-irr i No C-35flO onJ C-293
1. SITE HISTORY AND BACKGROUND
In accordance with 15A NCAC 2H.0105(c)(2), Chemours Company FC, LLC (Chemours) has
prepared this Engineering Alternatives Analysis (EAA) for review by the North Carolina
Department of Environmental Quality (NCDEQ). The EAA supports the National Pollutant
Discharge Elimination System (NPDES) permit application for the discharge of groundwater
and surface water from locations along the proposed groundwater remedy alignment at the
Fayetteville Works Facility (the Site), Bladen County, North Carolina.
Pursuant to paragraphs 2(c)(i) and 3(b) of the signed Addendum to the Consent Order paragraph
12 (CO Addendum) entered by the court on October 12, 2020, Chemours will install a
groundwater extraction remedy supported by a barrier wall and capture seep flow originating
upgradient of the remedy and treat these waters prior to discharge. The Groundwater Treatment
System (GWTS) is to have a removal efficiency of 99%,as indicated by the three indicator per -
and polyfluoroalkyl substances (PFAS) constituents PFMOAA, PMPA and HFPO-DA1 from
this flow to meet the requirements and criteria stipulated in the Addendum to the CO. A
NPDES permit application and supporting EAA is a pre -requirement for the construction and
operation of the GWTS to treat water from the groundwater and upgradient seep flow.
The remedy, which includes groundwater extraction and a GWTS, is to commence operation
by March 15, 2023 per paragraph 3(b) of the Addendum to the CO. To meet this requirement,
Chemours intends to complete construction of the GWTS by April 1, 2022. Chemours will
need to pump and treat the water collected by the remedy. The GWTS therefore needs to be
operational prior to commencement of remedy and extraction network construction in June
2022 to protect the integrity of the barrier wall.
The Site is located on NC Highway 87, 15 miles southeast of the City of Fayetteville, and south
of the Bladen-Cumberland County line. The Site encompasses 2,177 acres of relatively flat
undeveloped open land and woodland bounded on the east by the Cape Fear River, on the west
by NC Highway 87, and on the north and south by farmland. The site's location is shown in
Figure 1.
E.I. du Pont de Nemours and Company (DuPont) purchased the property in parcels from
several families in 1970. The Site's first manufacturing area was constructed in the early 1970s.
Currently, the Site manufactures plastic sheeting, fluorochemicals, and intermediates for
plastics manufacturing. A former manufacturing area, which was sold in 1992, produced nylon
strapping and elastomeric tape.
' PFMOAA - perfluoro-2-methoxyacetic acid
PMPA - perfluoro-2-methoxypropionic acid
HFPO-DA - hexafluoropropylene oxide-dimer acid
TR0795 1 June 2021

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NC I-irr i No C-35flO onJ C-293
DuPont sold its Butacite® and SentryGlas® manufacturing units to Kuraray America, Inc. in
June 2014. In July 2015, DuPont separated its specialty chemicals business into a new publicly
traded company named The Chemours Company FC, LLC. With this separation, Chemours
became the owner of the entire 2,177 acres of the Fayetteville Works along with the
Fluoromonomers, Nafion® membranes, and Polymer Processing Aid (PPA) manufacturing
units. The polyvinyl fluoride (PVF) resin manufacturing unit remained with DuPont.
In addition to the manufacturing operations, Chemours operates two natural gas -fired boilers
and a biological wastewater treatment plant (WWTP) for the treatment of DuPont and Kuraray
process wastewater and sanitary wastewaters from DuPont, Kuraray, and Chemours.
TR0795 2 June 2021

Geasyntec °
consultants
Legend
- Site Boundary
- Nearby Tributary
t`. _7a narpnachei,a Area
hkmMenufecwrig Ares
Dnrl mange.. pan as a{nl w -o a rrescre.n=Sao orarng wax d Ore rren,rewhy ardrrlien Sire lie.
o oia oseou o0 nadolol. f pso[mcrVn. A .. Ude. ream.. ara mnaaiebn naalef elure uma �gornd.aa feria.
2Theonrnd Cape Feer KrerifaYpmrn»ceM��ah`exed on rpendarn Sum ArrGS O.. rod Non Gator. ❑epauneerd
3Enn�'ru�md Gml'If On'pgGl "e,G Ye'Veh.. GeegapM1io.CUYi'Aikua DS. USDA. u.GS...GRID. ION. end gre
ee:
Site Location Map
Chemoore Fayettrodle Wal®. North Carolina
Chemours-
Ralagh 1
Jury 2020
Figure 1: Site Location Map
Figure
1
Ccosyn ec [:oueeIYu irx of NI:. RC.
NC I-irransl' Nee: C-35(NI mt.' C-293
TR0795 3 June 2021

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consultants
Grusymcc [:uueulhm ix%of NI:. RC.
NC I-irr i No C-35flO onJ C-293
2. PROJECT SUMMARY
The groundwater and upgradient seep flow will be captured west of a newly constructed
groundwater remedy consisting of extraction wells and supported by a barrier wall. The location
of the GWTS is also anticipated to be in the vicinity of the Site's Outfall 002 discharge. The
preliminary location is shown in Figure 2.
Legend
6/ Extraction well
Planned groundwater remedy route
Figure 2: Remedy Alignment & Proposed Groundwater Treatment System Location
The GWTS will be comprised of a series of chemical and physical separation steps. Chemical
oxidation and pH adjustment will first be employed to precipitate metals, such as iron, to
prevent downstream contamination or fouling of the granulated activated carbon (GAC) media.
The precipitated metals and other particles above an appropriate control threshold will be
removed via ultrafiltration membranes or some other suitable separation technology. The
filtered effluent will then be treated for per- and polyfluoroalkyl substances (PFAS) by GAC
adsorption. The reject from the filtration and GAC systems will undergo dewatering through a
thickening tank and filter press or centrifugation, from which the sludge cake will be disposed
of offsite and the press water will be recycled to the influent of the thickening tanks. Periodic
backwashing will extend membrane and carbon media life, and the carbon will be removed and
replaced based on breakthrough monitoring of several three -vessel carbon trains in a lead -
middle -lag arrangement. Associated design elements such as pumps, piping, electrical,
instrumentation and control for interlocks, mechanical and civil/structural elements will be
finalized during the detailed design phase. This design concept may be optimized based on
ongoing benchtop studies and data acquisition.
TR0795 4 June 2021

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NC 1-ire111.0 No C-3500 mt.' C-293
Additional process details associated with the treatment system are discussed later in this
document, under the "Direct Discharge Evaluation" section. A conceptual Process Flow
Diagram (PFD) showing the treatment schematic is also discussed in the same section.
3. STEP 1— ALLOWABILITY OF PROPOSED DISCHARGE
3.1 Analysis of Allowable Discharge Criteria
Based on the CO, the remedy will intercept groundwater and capture dry weather flow plus
stormwater from 0.5-inch or less storm events from seeps daylighting upgradient of the remedy
alignment. The water will be treated and discharged through the pipe which conveys the
existing Outfall 002 effluent to the Cape Fear River. All the intercepted and captured waters'
streams were flowing towards either the Cape Fear River or one of its tributaries of Willis
Creek and the Old Outfall. Therefore, no new flow will be added to the Cape Fear River that
would not have been introduced under the current conditions.
Applicability of the local government review and a stepwise assessment for each potential
restriction of the receiving watetbody per the NCDEQ EAA guidance document is addressed
below. The NCDEQ EAA guidance language is in italics, and a discussion follows.
3.1.1 Applicability of the Local Government Review
Per the EAA guidance document, the North Carolina General Statute 143-215.1 (c)(6) allows
input from local governments regarding the issuance of NPDES permits for new non -municipal
domestic wastewater treatment facilities. As this facility is intended to treat groundwater and
surface water containing PFAS at an existing industrial facility due to a consent order, local
government review form does not need to be completed.
3.1.2 EAA Guidance on Potential Restrictions
EAA Guidance: Zero flow stream restrictions [15A NCAC 2B.0206(d)(2)1 apply to oxygen -consuming
waste in zero flow streams. In order to determine streamflow at the proposed discharge location,
contact the U.S. Geological Survey at 919-571-4000.
EAA Guidance on Streamflow: Low flow data (specifically, drainage area, summer and winter 7Q10,
average flow and 30Q2 flow statistics) are required to support the EAA.
The Cape Fear River is the receiving body for the discharge from the GWTS. This discharge
will mix with effluent from Outfall 002 in the outfall's discharge pipe prior to reaching the
river. The river's hydrologic unit code is 03030005. Based on available data from the U.S.
Geological Survey at the William O. Huske Lock and Dam (Station ID 02105500), the annual
average streamflow from January 2011 to January 2021 was 4,424 cubic feet per second (cfs);
the Cape Fear River is a perennially flowing river. The seven-day, 10-year average low (7Q10)
flow is 467 cfs. As such, the Cape Fear River is not a zero -flow stream, and zero -flow stream
restrictions do not apply.
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The proposed discharge will consist of ground water and surface water collected, treated (by
physical/chemical precipitation and carbon adsorption), and discharged into the pipe that
conveys Outfall 002 effluent to the Cape Fear River. The discharge therefore will be of a higher
quality than the existing flows of groundwater and surface water and also have a lower amount
of oxygen consuming constituents than are currently present. There will also be no addition of
any external flow or constituents since this water is currently discharging to the Cape Fear
River. As previously stated, zero flow discharge restrictions are not applicable to the current
scenario because the Cape Fear River is not a zero -discharge stream. Additionally, the organic
compounds in this water will exert limited oxygen demand and will be further reduced due to
the GWTS. See Engineering Report — Treatment of Groundwater and Seeps Water (Geosyntec,
2021) for 5-day biological oxygen demand analytical results. Furthermore, this document
provides details of the unit processes for the GWTS.
EAA Guidance: Receiving stream classification restrictions [e.g., ORW, WS, SA, NSW, and HQ class
waters have various discharge restrictions or require stricter treatment standards]. Stream
classifications are available on the DWR Classification and Standards/Rule Review Branch website:
(http://portal.ncdenr.org/web/wq/ps/csu), while wastewater discharge restrictions for various stream
classifications are presented in state regulations [ 15A NCAC 2B. 0200].
A review of publicly available resources, such as the NCDEQ Surface Water Classifications
maps, indicates the Cape Fear River is classified as WS-IV. WS-IV waters represent waters
used as sources of water supply for drinking, culinary, or food processing purposes for
moderately to highly developed watersheds. These waters are also protected for Class C uses
(fishable/swimmable). Figure 3 shows the Cape Fear River and its classification.
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527/2021. 3:41.32 PM
Classlfiralon W S-FV
$:3G,112
• 0.36 4.7
Ccosyn CV115 Imix%of NI:. RC.
NC 1.i.111.0N: C-35(10 oli J C-293
1A(ri
O 0.6
Figure 3: Cape Fear River Classification
2bn
As previously stated, the level of treatment expected from the GWTS will be such that negative
water quality impacts are not anticipated as a result of the proposed discharge.
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EAA Guidance: Basinwide Water Quality Plans. These basin -specific plans list NPDES permitting
strategies that may limit wastewater discharges to particular streams within the basin due to lack of
stream assimilative capacity, etc. Basin plans are available on the DWR website, or you may contact
the DWR Basinwide Planning Branch (http://portal.ncdenr.org/web/wq/ps/bpu).
The 2005 Cape Fear River Basinwide Water Quality Plan2 is the most recent water quality plan
available. Details for Subbasin 03-06-15, which includes assessment unit 18-(26)c, are found
in Chapter 15. According to the water quality plan, the assessment unit is impaired for aquatic
life because of high levels of chlorophyll -a. Nutrient levels behind Lock and Dam 3 (i.e. the
W.O. Huske Dam) were high enough to support nuisance algal growth and during the drought
of 2001 and 2002, dissolved oxygen levels behind the structure dropped below the standard.
When stream flow conditions returned to normal, the dissolved oxygen levels recovered.
Chapter 15 of the report did not include the NPDES permit for Chemours (formerly DuPont);
however, DuPont was listed in Chapter 16 as discharging to Subbasin 03-06-16. The specific
location of the discharge from the DuPont WWTP was not given. According to the water quality
plan, the Cape Fear River mainstem in Subbasin 03-06-16, assessment unit 18(26)d also
experiences high levels of chlorophyll -a and low levels of dissolved oxygen. However, it
appears these segments were not included on the state list of impaired waters, due to lack of
data.
Based on the available data, the proposed discharge will be low in organic carbon and organic
nitrogen and should not cause a dissolved oxygen reduction. The discharge will include treated
flow from groundwater seeps that are currently discharging directly into the Cape Fear River.
The treatment of the seep flow will improve water quality conditions in the receiving water
body.
EAA Guidance: Impaired waters and [total maximum daily loads or] TMDLs. Certain
waterbodies listed as impaired on the 303(d) list and/or subject to impending TMDLs may
have wastewater discharge restrictions. The list of 303(d) impaired waters is located on the
DWR website, or you may contact the DWR Modeling and Assessment Branch
(http://portal.ncdenr.org/web/wq/ps/mtu).
Based on the latest available 303(d) list for the Cape Fear River Basin (North Carolina 2020
Draft 303(d) List3) the Lower Cape Fear River assessment unit 18-(26.25)b, where the
Chemours facility is located, is not impaired. This assessment unit stretches from Grays Creek
to the Lock and Dam 3 and receives a rating of BLUE, indicating all assessments are meeting
criteria. The assessment unit 18-(26.25)c, beginning at Lock and Dam 3 to approximately 0.5
2 https://deq.nc.gov/about/divisions/water-resources/planning/basin-planning/water-resource-plans/cape-fear-
2005, accessed 2/27/2021
3 NC 2020 DRAFT 303D LIST PR.pdf, accessed 2/26/2021
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miles upstream of Smithfield Packing Company's intake, is rated GRAY indicating that the
available data are inconclusive. This stream segment is located immediately downstream of
the Chemours' facility. The Cape Fear River is not listed on the 303(d) list as impaired at this
location, and there are no approved TMDLs that apply to the Cape Fear River at this location
that would impose discharge restrictions on a future permitted discharge.
EAA Guidance: Presence of Endangered Species. If endangered species are present in the
proposed discharge location, there may be wastewater discharge restrictions. Endangered
species information may be included in the Basinwide Water Quality Plan, or you may
contact the U.S. Fish and Wildlife Service (919-856-4520), N.C. Wildlife Resources
Commission (919-733-3633), or the N.C. Natural Heritage Program (919-733-7701).
The Environmental Conservation Online System (ECOS) was reviewed to determine if any
there are any endangered species present near the proposed discharge location. ECOS lists
endangered species by county. The list for Bladen County includes one aquatic species, the
Atlantic pigtoe clam, Fusconaia masoni, as a proposed threatened species. However, further
review using the Information from the Planning and Consultation4 (IPaC) online planning tool
did not identify the Atlantic pigtoe clam at the location. It should be noted that while there are
no critical habitats at this location the online lists include two endangered flowering plants:
American chaffseeed (Schwalbea americana), and rough -leaved loosestrife (Lysimachia
asperulaefolia) that could be found in the area. The northern long-eared bat (Myotis
septentrionalis), wood stork (Mycteria americana), and American alligator (Alligator
mississippiensis) are listed as threatened and the red -cockaded woodpecker (Picoides borealis)
is listed as endangered. The monarch butterfly (Danaus plexippus) is listed as a candidate
species by ECOS. Given the lack of critical habitat and the transient (mobile) nature of many
of these species, it is highly unlikely they would be impacted by the proposed discharge.
4 https://ecos.fws.gov/ipac/location/VDIGH7JAVJCIXEDEUW45OL3YKU/resources, accessed 2/27/2021
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4. STEP 2: TREATMENT SYSTEM FLOW PROJECTION
Extracted groundwater and captured seep water will come from three water bearing units
present at Site listed in order from topmost to bottom most: the Perched Zone, the Surficial
Aquifer, and the Black Creek Aquifer. The total estimated flows are from the various sources
are described below in Table 1. Extracted groundwater will come primarily from the Black
Creek Aquifer with a relatively minor component of flow originating from the Surficial
Aquifer. The seeps captured at the barrier wall will receive flow from both the Perched Zone
and Surficial Aquifer. Figure 4 depicts the cross section of the remedy alignment and shows
the thicknesses of the Surficial and Black Creek Aquifer locations, and a description of each
water bearing until described below.
Fate and transport analyses at the Site demonstrated groundwater and onsite seeps as two
primary PFAS transport pathways to the Cape Fear River (Geosyntec, 2019a, 2021a).
Groundwater seeps, a common hydrogeological feature in sloping terrain such as that at the
Site, has also been determined to be one of the PFAS release mechanisms to surface water
receptors. The remainder of this sub -section provides a geological description of the water
bearing units and the methods by which conservative estimates (i.e. high end) flow rates for
extracted groundwater and seeps were developed.
4.1 Geological Descriptions
Perched Zone: The Perched Zone is a relatively thin, spatially limited layer of groundwater
present in silty sands to a depth of about 20 feet below ground surface. Groundwater in the
Perched Zone is recharged through precipitation onsite. Groundwater flows radially away from
a groundwater mound in the Perched Zone. This leads to groundwater discharge to the east at
seeps on the edge of the bluff (i.e. towards the river), to the south toward the Old Outfall 002,
and to the north and to the west downwards through the geological sequence towards the
Surficial and Black Creek Aquifers (BCA).
Surficial Aquifer: The Surficial Aquifer is an unconfined silty sand aquifer lying atop the
Black Creek Confining Unit and is present beneath the Perched Clay Unit. Groundwater in the
Surficial Aquifer flows towards the bluff faces at the Site (i.e. towards the river) — It flows both
north, east and west toward surface water bodies (Willis Creek, Seeps, Old Outfall 002) and
discharges into them as seeps.
Black Creek Aquifer: The BCA is comprised of fine to medium grained sands. The BCA
directly adjacent to the Cape Fear River. The BCA is interpreted to be the only transmissive
groundwater zone at Site in direct contact with the Cape Fear River. Groundwater in the BCA
flows from west to east towards the Cape Fear River.
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Gcosynl Cournhs its of NC, P.C.
NC LiroNso Nu; {;- 62O grta C•295
0
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90
80
70
60
50
40
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-20
High Resolution Cross Section with Interpreted Geology
Chemoms Fay etterile Works. North Carolina
Geosyntec ti
00115tdla013
Raleigh
2, x;;
May 2021
Figure
4
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Figure 4: High Resolution Cross Section with Interpreted Geology
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4.2 Extracted Groundwater Flow Estimate
To model groundwater remedy scenarios in support of preparing a groundwater remedy design,
a three-dimensional (3D) transient -state finite element numerical groundwater flow model was
constructed in FEFLOW version 7.2 (DHI-WASY). The model domain covers an area
approximately 72,690,473 square ft (2.61 square miles) and models the hydrogeology of the
Site. The model varies in thickness from about 170 feet near the plant to 55 feet at the base of
the bluff adjacent to the Cape Fear River. The North Carolina Department of Public Safety
Light Detection and Ranging (LiDAR) elevation model was used to present ground surface
topography (NC DPS, 2015), while topography of the underlying model geology layers were
based on lithostratigraphic data obtained from Site monitoring wells, soil borings, hydraulic
profiling tool, and cone penetration tests contained in the three-dimensional visualization
model, EVSTM.
The model was calibrated to groundwater conditions and measurements observed from 2018
to 2020 using data from 139 Site wells: 60 wells in the Perched Zone, 32 wells in the Surficial
Aquifer, and 47 wells in the BCA. Results indicate that the model simulation compares
reasonably well with the observations from monitoring wells (Figure 5). This outcome
provided validation of the groundwater model's ability to simulate the field conditions.
The groundwater model was used to simulate remedy scenarios to identify which combination
and positioning of extraction wells and barrier wall would meet the CO Addendum paragraph
3(b) objective of intercepting groundwater flowing from under the facility towards the Cape
Fear River. The results of the remedy modeling indicates objectives can be met with extraction
wells in the BCA spaced at approximately 200 feet intervals with pumping rates varying
between 5 to 30 gallons per minute (gpm) per well with targeted extraction of the Surficial
Aquifer in specific locations. The progression of the design process presently indicates
approximately 60 groundwater extraction wells along the length of the remedy. These flow
simulations indicate extraction flow rates of 150 and 800 gpm from the Surficial and Black
Creek aquifers respectively.
4.3 Captured Seep Water Flow Estimate
The remedy is required to capture and treat the baseflow volume of seeps daylighting
upgradient of the remedy and stormwater flows from rain events of 0.5 inches or less. The
captured seep base flow rates were estimated using measured data from flumes and the
stormwater flows estimated using a hydrological model created using U.S. Environmental
Protection Agency's (EPA) Storm Water Management Model (SWMM).
The flumes installed in Seep A and B at locations A-4 and B-2 were used to estimate dry
weather baseflow rates (Figure 6). These two locations are both considerably downgradient of
the capture locations and therefore provide a high -end estimate of expected flow rates as more
seepage derived flow reaches these locations than at the capture location. Based on over 270
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days of observation for each flume, the 95th percentile instantaneous dry weather flow readings
for Seep A was 31 gpm and Seep B was 130 gpm.
Stormwater flows from the seeps were estimated assuming 24-hour equalization storage for
pulses of volume from storm events up to 0.5 inches. The modeled volume of rainfall from
both seeps combined was estimated to be between 110,000 and 156,000 gallons. Equalized
over 24 hours, this results in a high end estimate of 108 gpm of flow.
4.4 Combined Flow Estimate
The present best estimate of flow to the GWTS was estimated from expected groundwater and
seep flows. Total expected groundwater flow was estimated via the results of the modeling
simulations and the seep flow was estimated via flume measurements that have been ongoing
since 2019. The estimated hydraulic loading in gpm from extracted groundwater and seeps for
the post -remedy construction condition is shown in Table 1.
Table 1: Hydraulic Loading of Representative Groundwater and Seep Sources
Source
Approximate Flow Rate
0
Seeps Baseflow
161 gpm
*
Seeps Stormflow
108 gpm
°
Groundwater from Surficial Aquifer
150 gpm
Groundwater from Black Creek Aquifer
800 gpm
Total Flow
1,219 gpm
* Seeps stormflow represents maximum increase over baseflow averaged over 24-hour period.
0 Seeps baseflow and Shallow Groundwater may include some double counting. Seeps baseflow represents the 95th
percentile instantaneous flow from each of Seeps A and B at location representative of the remedy capture location.
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Gcorymcc Conikkhas itsofNC, P.C.
NC LicerpA' No l {; -3E10 qua C•295
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- Sinulated Equipotendals (feet HAW BB)
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Figure 5: Numerical Modeling Simulated Groundwater Levels
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tirosyntcc CnuuJtm its of Yr., P.C.
NC Lira Nu; {; -35f0 qna 0 295
Legend
SeepAUpstream Capture
Point
Seep B Upstream Capture
Point
SeepA-4 Flume Location
Seep B-2 Flume Location
Planned Groundwater Remedy
Route
Seep
Estimated Watershed
JSeep A - Modeled Catchment
Seep B - Modeled Catchment
Seep A - Additional Catchment
Measured by Flume
73 Seep B -Additional Catchment
Measured by Flume
Notes:
1. Seep catchment areas were estimated using
geospatial methods and tools, and
based on lidar data collected for Chemours.
2. Seep locations identified visually as reported in
Geosyntec, 2019. Seeps and
Creeks Investigation Repot_ Chemours
Fayetteville Works. 26 August 2019.
3. Basemap source: Esn, DigitalGlobe, GeoEye,
Earthstar Geo-graphics,
CNESlAirbus DS, USDA, USGS, AeroGRID, IGN,
and the GIS User Community.
500 250 0 500 Feet
Seep Drainage Areas
Chemours Fayetteville Works, North Carolina
Geosynteco'
nonsuhants acted. ccee uecax
Raleigh
March 2021
Figure 6: Seep Flume and Proposed Capture Locations
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4.5 Pumping and Conveyance Design
Groundwater modeling remedy development presently indicates approximately of 50 Black
Creek Aquifer and 10 Surficial Aquifer extraction wells will be required to intercept
groundwater. The combined maximum total flow rate produced from these wells is expected
to be 950 gpm.
Each well pump is expected to extract approximately 5 to 30 gpm and will be sized to have
additional flow capacity for contingency. The extraction wells will be of high -density
polyethylene (HDPE) construction below finished grade, whereas the wellhead will be of
polyvinyl chloride construction.
Each wellhead will then tee into their corresponding conveyance line (i.e., North or South
Force mains), constructed of HDPE. Approximately two thirds of the required extraction wells
will convey groundwater through the North Force main while the remaining third is conveyed
via the South Force main. The conveyance lines will be sized to accommodate the total
collected flow of the extraction with added contingency to allow for increased extraction rates
if required. Extracted groundwater will be conveyed to a surge tank prior to being treated by
the GWTS.
The seep flow will be impounded at or near seep capture locations (impoundment storage) to
provide equalization storage during rainfall events and remove readily settlable/suspended
solids prior to being conveyed to a break tank and treated by the GWTS.
The total maximum dry weather flow to the GWTS, after the groundwater remedy is fully
operational, including seep flow, is estimated to be 1,111 gpm. Total flow over a 24-hour
period with up to 0.5 inches of rainfall is estimated to average 1,219 gpm. The design flow rate
for the GWTS was selected to be 1,500 gpm to allow for increased groundwater extraction
from the extraction wells and potential changes in post -installation flow behavior from the
seeps.
At the break tank, the influents from the extracted groundwater and the seeps will be combined.
The effluent of the equalization tank will then be drawn on demand by the GWTS. The
impoundment storage will be dredged periodically, and solids characterized and disposed of at
an appropriately designated facility.
5. STEP 3 ALTERNATIVES
Following consultation with the NCDEQ, only the alternative cases below were considered in
the Steps 3 and 4 assessment.
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5.1 Technologically Feasible Discharge Alternatives
5.1.1 Connection to Existing Public Treatment Plant
Conveying the effluent from the new treatment system for the groundwater and seeps flow to a
local Publicly Owned Treatment Works (POTW) has been evaluated. The nearest POTW to
the site is Fayetteville Public Works Commission (PWC) Rockfish Creek Water Reclamation
Facility (WRF) located approximately nine miles north of the Chemours site. The nearest
public sewer connection to this facility is approximately six miles north of the Chemours site.
The Fayetteville PWC has indicated that they will not accept the treated water. A letter
reflecting this is attached as Appendix A. The PWC Rockfish Creek WRF uses biological
treatment technology (i.e. for the treatment of domestic sewage) and does not provide treatment
for residual PFAS compounds in their influent. The extracted groundwater and captured seeps
will be treated for 99% removal of PFAS indicator compounds, and this process will also
remove other residual organic compounds in the water such that there will be minimal residual
oxygen demand in the treated effluent. Thus, the PWC cannot provide any additional effective
treatment for the treated groundwater and seeps, and such inflow would only serve to dilute the
plant load, add hydraulic loading, and result in increased operational costs and possible
performance issues for no net environmental benefit.
Additionally, the City of Fayetteville's Sewer Use Ordinance precludes the discharge of surface
water into the city's sewer system. As such there are no local public sewer connections
available to receive the treated groundwater and seeps flow, and hence discharging the water to
a POTW is not a feasible option
5.1.2 Wastewater Reuse
Reusing the treated effluent from the new groundwater and seep flow treatment system within
the manufacturing process or as non -contact cooling water was evaluated in lieu of discharging
the treated effluent from the GWTS back into the Cape Fear River. Direct discharge was
determined to be the preferred option to wastewater reuse. First, the GWTS must operate year-
round. Groundwater is continually recharged and flowing and the seeps are perennial surface
water flows. Both these flows are primary pathways of PFAS to the Cape Fear River and per
the CO Addendum must be intercepted, treated, and then per GWTS requirements, discharged.
Meanwhile the facility does not operate continuously, and ceases manufacturing activities for
one month per year. During this time each year, and other periodic shutdowns, the GWTS
operation would be unable to discharge treated water and would consequently be limited in its
ability to accept and treat water needing treatment.
Additionally, reusing treated water at the facility would not have a beneficial impact on the
river. The volume of treated water would comprise approximately 14% of the Site's daily water
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use, thus offsetting only a small fraction of the water withdrawn from the river. Treated effluent
water reuse would also not change the water balance or the PFAS loading to the Cape Fear
River.
5.1.3 Direct Discharge
This section discusses the direct discharge of treated groundwater and seep water into the
receiving body (Cape Fear River), and the treatment process of the proposed treatment system
supported by a conceptual PFD. A detailed account of each unit operation shown in the PFD
can be found in the attached Engineering Report (Geosyntec, 2021c). The Engineering Report
also contains the data considered in the engineering design.
Based on turnkey vendor proposals currently under consideration, the GWTS is assumed to be
comprised of the following series of treatment units:
1. Metals oxidation;
2. Ultrafiltration (UF) or similar solids separation technology;
3. Granular Activated Carbon (GAC) adsorption;
4. Solids Handling & Dewatering; and
5. Ancillary processes for backwashing and residuals handling.
The influent oxidation system will be designed to help ensure complete oxidation of reduced
iron species (or other dissolved metals), by means of pH adjustment and possible addition of
inorganic coagulant and/or flocculant. Following oxidation, flow will proceed to the solids
separation unit in which particle sizes above an appropriate control threshold will be removed.
The filtrate will then be pumped to the GAC adsorption process, which will remove the PFAS
and other contaminants from the water. The GAC effluent will undergo further pH adjustment
back to near -neutral conditions and then be discharged to the Cape Fear River via the pipe that
conveys existing flows from Outfall 002 to the river.
The solids separation unit reject, solids separation unit cleaning, and GAC backwash water will
collect in one or more thickener tanks. The thickened solids will be dewatered using a filter
press or centrifuge. Sludge cake will be transferred into hoppers that will be trucked off -site for
disposal, at a permitted waste disposal facility. The dewatering filtrate will be returned to the
head of the plant and blended with the influent downstream of the oxidation tanks. A backwash
water tank will store a limited volume of treated water to supply GAC backwash, polymer
dilution, and other process water requirements. A GAC backwash waste tank will collect
backwash water and bleed it back into the treatment process downstream of the oxidation tanks.
Paragraph 2(c)(i) and paragraph 3(b)(ii) of the Addendum to the CO establish treatment
standards for the GWTS, as measured by the concentrations of indicator parameters of HFPO-
DA, PMPA, and PFMOAA. The long-term seep remediation objective at paragraph 2c(i)
requires a 99% reduction in annual mass loading of PFAS for the treated seep water. The
objective for the groundwater treatment in paragraph 3(b)(ii) is to provide a minimum PFAS
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removal efficiency of 99% of treated groundwater. Based on vendor experience, Chemours'
experience at Outfall 003, and outcomes of past treatability pilot studies, it is anticipated that
these treatment requirements will be met. In addition, Chemours is currently performing
treatability studies based on anticipated wastewater characterizations of the groundwater and
seeps.
A conceptual PFD of the GWTS and the associated sludge handling system is shown in Figure
7.
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Gttwynl“CouuJim It% ofNf., P.C.
NC 'AMMO No: C-3500 end G-295
Feed
Frac tank
Frac tank
Caustic
Chlorine
Coagulant
Anionic
polymer
decant
Anionic polymer
UF
Vessel
OF
Vessel
OF
Vessel
UF
Vessel
(JF
Vessel
F-12SO4
pH to 3-5
Frac tank
Frac tank
CIP
4-
Caustic
SBS
12' diameter vessels
GAC
GAG
GAC
CAC
GAG
GAG
GAG
GAG
GAC
Caustic
pH to 6-9
LJF Reject
Cone
Battcm
Tank
Sludge
Cone
Bottom
Tank
Decant
Frac tank
Filtrate
I
Cationic polymer
Filter
Press
Solids
■
Solids
roll -off
Frac tank
To Outfall
Frac tank
To GAC B/W,
Rinse, Sluice
GAC
— Baclstivash
Out
GAC System
Solids handling
Pre- and post- treatrneni
Figure 7: Conceptual Process Flow Diagram of Primary Treatment Process and Solids Recovery Process
20
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6. STEP 4 ECONOMICS
6.1 Economic Feasibility of Alternatives
A 20-year Present Value of Costs Analysis (PVCA) has been performed for the Direct
Discharge option which has been evaluated to be the preferred option. A PVCA was also
performed for the wastewater reuse option. Use of an existing POTW was determined to
be technically unfeasible and therefore is not included in the economic evaluation.
A preliminary design was prepared for the Direct Discharge option along with the associated
costs. The estimate uses standard factors for cost estimation, and as such is a Rough Order
of Magnitude estimate. For the PVCA costs, future expenditures have been converted to
a present value cost at the beginning of the 20-year planning period. Based on EPA
guidance, a discount rate of 3.5% for a 20-year period has been used in the analysis.
The PVCA includes all costs associated with construction, startup and annual operation
and maintenance costs. Costs also include, but are not limited to, the following:
• Capital costs
• Equipment costs
• Labor costs
• Installation costs
• Design costs
• Operations and maintenance costs
• Laboratory costs
• Waste disposal costs
• Labor costs
• Utility costs
Cost information is preliminary and has been generated from the following sources:
• Non -binding vendor quotes
• Publicly available land costs
• Previous project experience and bids
• Cost estimation manuals (e.g. Means Construction Index) and standard factors
TR0795 21 June 2021

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Because of the turnkey nature of the proposed commercial treatment system, many of
these cost elements are captured within a few broader cost categories described below.
For example, the majority of facility operating costs are captured in a monthly operating
contract fee.
6.1.1 PVCA Calculation Method
The following standard formula per the guidance document for computing the Present
Value has been utilized:
Where:
PV = Co +
PV = Present Value of costs
Co = costs incurred in the present year
Ct = costs incurred in year t
t = time period after the present year, where t = 0
n = ending year of the life of the facility
r = current EPA discount rate
6.1.2 PVCA Summary
A summary cost table presenting the present worth for the treatment alternatives
considered at a design flow of 1,500 gpm, are presented as Table 2. Detailed cost
estimates are provided in Appendix B.
TR0795 22 June 2021

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Table 2: Present Value Cost Analysis Summary Table
Scenario
Treatment Option
Total Capital
Cost (Co)
Total Annual
O&M Cost (C)
Present Value
1
Direct Discharge -only
Treatment System
$8,500,000
$4,200,000
$68,200,000
2
Treated Effluent Reuse
$9,900,000
$4,200,000
$69,600,000
7. CONCLUSION AND PATH FORWARD
In summary, the groundwater and seep flow associated with the newly proposed
groundwater remedy will be collected and treated (by physical/chemical precipitation,
filtration and carbon adsorption). The preferred alternative is to discharge the treated
groundwater and seep water into the existing pipe which also conveys the effluent from
Outfall 002. It is therefore anticipated that the environmental impacts associated with the
current groundwater onsite will be significantly diminished and the treated water will
exhibit a significant reduction in PFAS target compounds, total suspended solids, and
dissolved metals. This will reduce the impact of these pollutants in the Cape Fear River.
Onsite water reuse would limit the operation of the GWTS when the Site is not
discharging and provides no additional benefit to the river.
Since the treated effluent presents a substantially reduced environmental impact to the
Cape Fear River relative to pre -remedy conditions (i.e. prior to construction of the
groundwater extraction network and supporting barrier wall), Chemours considers this
option to be the most feasible and environmentally beneficial to address the requirements
outlined in the Addendum to the CO. This evaluation is further supported by current
treatment successes at the existing Outfall 003 treatment facility, and the additional
technical details regarding treatment presented in the Engineering Report.
Approval of this EAA and subsequent permit authorization is respectfully requested as
expeditiously as possible so that Chemours can meet the requirements of the Consent
Order and Addendum.
TR0795 23 June 2021

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8. REFERENCES
Geosyntec, 2019a. Cape Fear River PFAS Mass Loading Model Assessment and
Paragraph 11.1 Characterization of PFAS at Intakes. Chemours Fayetteville
Works. August 2019.
Geosyntec, 2019b. Corrective Action Plan, Chemours Fayetteville Works. December
2019.
Geosyntec, 2021 a. Cape Fear River PFAS Mass Loading Assessment — Fourth Quarter
2020 Report. Chemours Fayetteville Works. March 2021.
Geosyntec, 2021b. Pre -Design Investigation Summary, Chemours Fayetteville Works.
March 2021.
Geosyntec, 2021c. Engineering Report — Treatment of Groundwater and Upgradient
Seeps Water. June 2021.
North Carolina Department of Public Safety (NC DPS), 2015. North Carolina's Spatial
Data Download. https://sdd.nc.gov/
TR0795 24 June 2021

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APPENDIX A - PWC REFUSAL TO
ACCEPT TREATED WASTEWATER
TR0795 June 2021

DARSWEIL L. ROGERS, COMMISSIONER
WADE R. FOWLER, JR., COMMISSIONER
EVELYN O. SHAW, COMMISSIONER
D. RALPH HUFF, III, COMMISSIONER
DAVID W. TREGO, CEO/GENERAL MANAGER
Parsons
4701 Hedgemore Drive
Charlotte, NC 28209
Attention: Michael Robinson, P.E.
Dear Mr. Robinson:
OWN UTILITY
September 11, 2019
FAYETTEVILLE PUBLIC WORKS COMMISSION
955 OLD WILMINGTON RD
P.O. BOX 1089
FAYETTEVILLE, NORTH CAROLINA 28302-1089
TELEPHONE [phone]
WWW.FAYPWC.COM
RE: Sewer/POTW Connection Near Chemours,
This is in response to your inquiry to this office regarding the above referenced subject.
More specifically, you mentioned that Chemours is required to treat PFAS impacted water from
a surface water body on -site. The water is groundwater that is daylighting into a ditch and
ultimately flowing to the Cape Fear River. In order to obtain an NPDES permit, it is necessary
to get a letter from the local POTW indicating that they will or will not accept it. It is further
understood that Chemours is required to remove 99% of two specific constituents (HFPO-DA
and PFMOAA). As such the water would have a maximum of 50 parts per trillion of HFPO-DA
and around 800 ppt of PFMOAA (along with lower levels of other PFAS constituents).
Currently, PWC owns and operates a water reclamation facility, Rockfish Creek WRF,
approximately 9 miles to the north of the Chemours site at the intersection of Highway 87 and
Old Wilmington Road. The nearest collection lines that discharge to this facility are located
approximately 6 miles north of the Chemours site. In addition, this facility is not designed to
treat wastewater containing HFPO-DA, PFMOAA or other PFAS and PWC will not be able to
accept this wastewater.
If there are questions or if additional information is needed, please let me.
Si cerely,
oseph E. Glass, PE
Manager, Water Resources Engineering
BUILDING COMMUNITY CONNECTIONS SINCE 1905
AN EQUAL EMPLOYMENT OPPORTUNITY EMPLOYER

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APPENDIX B - COST ESTIMATES
TR0795 June 2021

Cost Estimate for Direct Discharge
Chemours Fayetteville Works, North Carolina
Basis of Cost Estimate (Scope and Assumptions):
Direct Discharge of treated effluent to existing Outfall 002.
Estimate is based on currently available budgetary quotations for turnkey treatment system.
Costs associated with collection and conveyance have been excluded since they are the same for all cases.
Construction cost factors are representative and considered sufficient for the Rough -Order -of -Magnitude nature of the estimate.
Item
Qty Unit Unit Cost Total
Notes
Capital and Construction Costs
GW EWs and Conveyance System
Turnkey Treatment System (Pretreatment, GAC, Solids Handling)
Land Costs
Raw Capital Costs
Installation Cost (Construction, Site Preparation, Civil, Structural)
Ancillary Cost (1&C, Piping -Mechanical & Electrical)
Total Capital & Construction Cost
Total Capital & Construction Cost (Including Equipment Protection)
Professional Services Costs
Engineering and Project Management
Construction Management, Project Management, General Conditions
Professional Services Subtotal
Process Package $ 3,500,000 $
$ - $
same for all scenarios
3,500,000 Suez
$ 3,500,000
50% of Raw Capital Costs $ 1,750,000
of Sum of Raw Capital
30% Costs and incl
Installation Cost
Sum of Raw Capital Costs, $ 5,250,000
Installation Cost
and Anciliary Cost
Total Capital &
12% of Construction Cost
Sum of Total
Capital &
Construction Cost,
Engineering/PM &
8% of Contingency Costs
Contingency 30%
Co,Capital Cost
+50%
-30%
Sum of Total
Capital &
Construction Cost
and
Engineering/PM
of cost
$ 5,250,000
$ 700,000
$ 700,000
$ 1,400,000
$ 1,800,000
$ 8,500,000
$ 12,800,000
$ 6,000,000
these costs are captured in
the turnkey price above
Annual Operations & Maintenance Costs
Electricity
GAC Usage & Replacement
Solids Disposal
Sampling & Analytical
System Operations, Maintenance, Equipment Rental, Consumables
Variable Cost of Treatment (vendor)
Annual O&M Subtotal
C,Annual Cost
+50%
-30%
n,Years 20
r,Discount Rate 3.5%
Present Worth Formula
'1 rtf -i
PW Factor for n Years 14.2124
$ 150,000
$ 800,000
$ 16,500
$ 55,000
$ 2,280,000
$ 883,000
$ 150,000 from turnkey demand est
$ 800,000 prelim vendor est
$ 16,500
$ 55,000
$ 2,280,000 turnkey monthly O&M
$ 883,000 turnkey flow -based fee
$ 4,200,000
$ 4,200,000
$ 6,300,000
$ 2,940,000
Total: Present Worth Value of Capital & Annual O&M Costs over 20 Years
+50%
-30%
$ 68,200,000
$ 102,300,000
$ 47,800,000
Rough Order of Magnitude (ROM) preliminary estimate (-30% to +50%) . Not for budgetary purposes and is only meant to be used for
interalternative comparison. The estimates have been prepared for guidance in project evaluation and implementation from the information
available at the time of the estimate. The final costs of the project will depend on final approved design, actual labor and material costs
(including but not limited to availability of land), and competitive variable factors. General conditions are subject to change which may lead to
a change in the estimate. Costs have been rounded up. Cost information is preliminary and has been generated from the following sources:
Non -binding vendor quotes (Sales tax may vary);Publicly available costs; Previous project experience and bids; Cost estimation manuals (e.g.
Means Construction Index) and standard factors
Page 1 of 1 June 2021

Cost Estimate for Treatment and Reuse
Chemours Fayetteville Works, North Carolina
Basis of Cost Estimate (Scope and Assumptions):
Reuse of treated effluent at Facility, using base treatment plant cost and assumed allowance for reuse infrastructure.
Estimate is based on currently available budgetary quotations for turnkey treatment system.
Costs associated with collection and conveyance have been excluded since they are the same for all cases.
Construction cost factors are representative and considered sufficient for the Rough -Order -of -Magnitude nature of the estimate.
Item
Capital and Construction Costs
GW EWs and Conveyance System
Turnkey Treatment System (Pretreatment, GAC, Solids Handling)
Allowance for treated water transfer (pumps, piping, tankage, trenching)
Raw Capital Costs
Installation Cost (Construction, Site Preparation, Civil, Structural)
Anciliary Cost (I&C, Piping -Mechanical & Electrical)
Total Capital & Construction Cost
Total Capital & Construction Cost (Including Equipment Protection)
Professional Services Costs
Engineering and Project Management
Construction Management, Project Management, General Conditions
Professional 5ervices Subtotal
Contingency
Co,Capital Cost
+50%
-30%
Qty Unit
Process Package
50% of
of
30%
Sum of
Unit Cost
$ 3,500,000 $
$ - $
Raw Capital Costs $
Sum of Raw Capital
Costs and
Installation Cost
Total
Notes
same for all scenarios
3,500,000 Suez
500,000
4,000,000
2,000,000
Applied to piping allowance
150,000 only. Balance of costs
included in turnkey costs.
Raw Capital Costs, $
Installation Cost
and Anciliary Cost
Total Capital &
12% of Construction Cost
Sum of Total
Capital &
Construction Cost,
Engineering/PM &
8% of Contingency Costs
Sum of Total
Capital &
Construction Cost
and
Engineering/PM
30% of cost
6,150,000
$ 6,150,000
$ 800,000
$ 800,000
$ 1,600,000
$ 2,100,000
$ 9,900,000
$ 14,900,000
$ 7,000,000
Annual Operations & Maintenance Costs
Electricity
GAC Usage & Replacement
Solids Disposal
Sampling & Analytical
System Operations, Maintenance, Equipment Rental, Consumables
Variable Cost of Treatment (vendor)
Annual O&M Subtotal
C,Annual Cost
+50%
-30%
n,Years 20
r,Discount Rate 3.5%
Present Worth Formula
PW Factor for n Years 14.2124
a
,72A
$ 150,000
$ 800,000
$ 16,500
$ 55,000
$ 2,280,000
$ 883,000
150,000
from turnkey demand est
800,000 prelim vendor est
16,500
55,000
2,280,000 turnkey monthly O&M
883,000 turnkey flow -based fee
4,200,000
$ 4,200,000
$ 6,300,000
$ 2,940,000
Total: Present Worth Value of Capital & Annual O&M Costs over 20 Years
+50%
-30%
$ 69,600,000
$ 104,400,000
$ 48,800,000
Rough Order of Magnitude (ROM) preliminary estimate (-30% to +50%) . Not for budgetary purposes and is only meant to be used for
interalternative comparison. The estimates have been prepared for guidance in project evaluation and implementation from the information
available at the time of the estimate. The final costs of the project will depend on final approved design, actual labor and material costs
(including but not limited to availability of land), and competitive variable factors. General conditions are subject to change which may lead to
a change in the estimate. Costs have been rounded up. Cost information is preliminary and has been generated from the following sources:
Non -binding vendor quotes (Sales tax may vary);Publicly available costs; Previous project experience and bids; Cost estimation manuals (e.g.
Means Construction Index) and standard factors
Page 1 of 1 June 2021