NC0003573_Initial Characterization of PFAS_20210921

tChemours M
Initial Characterization of PFAS in Process and
Non -Process Wastewater and Stormwater
July 30, 2021

P11 Initial Characterization and Ongoing Sampling
• P11(b-d) Program Overview
• P11 Location Categories and Recommendations
• Summary of Findings
— Distribution of concentrations
— Time series plots
• Statistical Analyses to Support Recommendations
• Summary of Recommendations
• Proposed Paragraph 11(d) Sampling Program Locations
Chemours-

b-d) Program Overview
• Paragraph 11(b) — Sampling Plan
— Bimonthly sampling plan approved on June 19, 2019
• Paragraph 11(c) — Initial Characterization
— 18-month period to characterize PFAS concentrations discharged to Outfall 002 at facility
including process wastewater, non -process water, and stormwater.
— Final report submitted December 19, 2020. Demonstrated certain areas do not contribute
to PFAS loading and made recommendations for sampling plan moving forward.
• Paragraph 11(d) — Ongoing Sampling
— Bimonthly sampling for two years based on initial characterization. Began January 2021.
Currently 7 months into program, 17 months remaining.
• Objectives for Presentation
— Overview of P11(c) results
— Request approval of recommended sampling plan changes beginning August 2021
CChemours

P11 Location
Categories
Location Category
Description
Recommendation
Intake River Water at Facility
Represents background PFAS concentrations
Continue sampling Table 3+ PFAS and EPA Method 537
Non-Chemours Process
Wastewater
Locations representing process wastewater from Kuraray
and DuPont
Represent at Influent to WWTP (Location 22)
Non -Contact Cooling Water
(NCCW)
Locations representing NCCW from Kuraray and
Chemours
Represent at Influent to WWTP (Location 22)
Stormwater
Locations containing only stormwater from throughout
the Facility
Represent Monomers/IXM SW with SWTS Sampling
Program; Represent western side of facility at
downstream Location 7A; Consider streamlining sample
locations in DuPont area
Stormwater-Non-Contact
Cooling Water
Locations representing commingled stormwater and
NCCW
Represent Monomers/IXM NCCW at single location
(Location 9A)
Wastewater Treatment Plant
Locations representing the WWTP influent and effluent,
and the Terracotta pipe, which prior to November 2017
conveyed Chemours process wastewater to the WWTP,
and will be decommissioned in 2021
Continue sampling Table 3+ PFAS at Influent (Location
22) and Effluent (Location 8)
Combined Flows to Outfall
002
Locations representing stormwater, NCCW, and process
wastewater from the combined flow pathways at the
Facility in the Open Channel to Outfall 002
Continue sampling Table 3+ PFAS at all locations
(Locations 7A, 7B, 7C)
Chemours-

P11(c) Sample Location
010040411111
Sample Category
Sample
Lttaiiort ID
Sample Location Description
Intake Riser Warer at Facility
1
Discharge point of excess river water {i.e.. water draws from the Cape Fear$R'er_ but not used A
process water or NCCW) to characterize background let els of PFAS
18
Kurarey process wastewater
Non -Clamours Process
Wastewater
19A
DuPont process Wastewater, Plant 1
19E
DuPoau process wasmwater, Plant 2
23E
Kuraae lahohamn•process wastewater
`CCIL
iA
Kuraav southern lased area NCCW discharge - Vacuum Condenser
6B
Kuraae southern leased area NCCW discha.._ - Resins Area
24A
Chemours Monomers LXM Vinyl Ethers South NCCW
24E
Chentsuis ]icoomers LXM Line 3 and Line 4 Extruder NCCW
24C
Challmers Monomers LAM Water Retain Header NCCW
. cTiwater
2
Kwaarnorthernleased area Rainwater discharge
3
Chemaars PPA arna stoamaarer discharge
4
Combined sbrmwater discharge from Kuraray northern leased area and Clamours PPA amen
5
Kurarav MAIM' In leased area store water
10
Chalmers Monomers LXM areastormwatr discharge
11
SNrmwater discharge from portion of grassy field to north of decommissioned Chemins Teflon area
Sbrmwater-ATCCW
7A
Combined srormwater and NCCW discharge from westemportion oldie Facility
9
Chansons Monomers 1XM NCCW and sbrmwater discharge raducting stogywater from Vinyl Ethers
South and Vinyl Ethers North
10A
Combined Chemolas Monomers Rai NCCW and stormaaInrdischarge
12
DuPont area southern drainage ditch stomnwater discharge and NCCW
13
DuPont area northern drainage ditch stmmwater discharge and NCCW
14
DuPont area southeast scmrmwater and NCCW discharge
15
Combined srormwater and NCCW discharge from eastern portioncf the Facility
21A
Sediment Basin South
21B
Sediment Basin North
Wastewater Treatment Plan,
8
Ou11sU 001 treated non -Clemons process wastewater dischargeto open unmet Go Urtfa11062
22
WU= combined influent
23A
Kurarav northern ]eased area combined process wastewater and NCCW; open grate on Terracotta pipe
Combined Flows to Duda 002
711
Combined sbrmwater and NCCW discharge from western portion oldie Facility and heated discharge
from WWrP
Combined sbrmwater and NCCW discharge from western portion oldie Facility, the eastern portion of
the Facility, and the DuPont Area acclimated discharge from WWI'P
20
OutfaU 002 pipe to Cape Fear Rica upstream of sump
Chemours Process Wastewater
16
Charmers Monomers LW Ares combined process wastewater
17A
Chemours PPA Area waste acid trailer
17E
Charmers PPA Area waste rinse water nailer
Chemours-

Summary of Findings
• The intake river water at the facility (Location 1) contains PFAS and
represents background level of PFAS at other sampling locations.
• EPA Method 537 PFAS were not statistically different or higher than intake
data
— One exception was Location 23A on the Terracotta pipe which has been
decommissioned as of April 21, 2021.
• Non-Chemours process wastewater locations (Locations 18, 19A, and
19B) and NCCW only locations (Locations 6A, 6B, 24A, 24B, and 24C)
PFAS concentrations were not statistically different or higher than intake
data
— One exception was Location 23B, which was influenced by the now decommissioned
Terracotta pipe.
CChemours

Summary of Findings
Primary sources of total Table 3+ PFAS are:
1. Locations comprising both stormwater and non -process
wastewater from the Monomers IXM area,
2. Stormwater-only locations, and
3. The WWTP effluent, including PFAS loadings from the
Terracotta pipe which prior to November 2017 conveyed
Chemours process water to the WWTP.
Chemours-

TT3+ (17 Compounds) Distribution of Concentrations by
Location
Legend
■ Intake River Water at Facility
■ Non-Chemours Process Wastewater Locations
■ Non -Contact Cooling Water Locations
Stormwater Locations
c
c
0
Stormwater-Non-Contact Cooling Water Locations ac,
■ Wastewater Treatment Plant Locations U
■ Combined Flows to Outfall 002 Locations
Process wastewater
only and non -process
wastewater only
locations similar to
Location 1: the intake
Total Table 3
100,000
10,000
1,000
100
10
Total Table 3+ Concentrations
•
•
•
•
1 •
•
•
•
•
•
s
•
•
•
•
•
•
•
•
•
•
•
• •
1
•
O
•
•
•
1
1
•
•
•
•
•
•
•
•
•
• i
• II•
• 1
i
•
1
• •
•
•
•
• •
•
•
•
1 18 19A 19B 23B 6A 6B 24A 24B 24C 2 3 4 5 10 11 7A 9 10A 12 13 14 15 21A 8 22 23A 7B 7C 20
Location
WWTP and
Terracotta Pipe
Open Channel
to Outfall 002
locations
Stormwater only
and non -process
wastewater/
stormwater
locations more
variable
Chemours-

EPA Method 537 Distribution of Concentrations by Location
Legend
■ Intake River Water at Facility
■ Non-Chemours Process Wastewater Locations
■ Non -Contact Cooling Water Locations
■ Stormwater Locations
■ Stormwater-Non-Contact Cooling Water Locations
■ Wastewater Treatment Plant Locations
■ Combined Flows to Outfall 002 Locations
Process
wastewater only
and non -process
wastewater only
locations similar
to Location 1:
River Intake
100,000
10,000
:Po
1,000
0
c
-o
0
100
r_
0
L
10
Chemours-
EPA Method 537 Concentrations
•
•
•
1
s
1
• •
1 18 19A 196 236 6A 6B 24A 246 24C
•
•
•
•
•
•
•
• • •
• •
•
1
•
•
•
•
•
1
•
E
•
•
•
1
•
2 3 4 5 10 11 7A 9 10A 12 13 14 15 21A
8 22 23A
7B 7C 20
Most locations have similar EPA Method 537 to Location 1
Open Channel to
Outfall 002
locations
WWTP and
Terracotta Pipe
Stormwater only and
non -process
wastewater/
stormwater locations
more variable but
similar

ime Series Plots Example: Non -Process Wastewater
100,000
Total Table 3+ Concentrations Non -Contact Cooling Water
10,000 -
TT3+ 17 Compounds:
0 1000 -
Non -process wastewater
locations show minimal
variability from Location 1
ro
0
1-
CChemours-
100 -
10 -
1
Location 1 Location 6A Location 6B
Location 24A Location 24B Location 24C
• April 2019 • June 2019 • August 2019 • October 2019 • December 2019 ■January 2020 • April 2020 ■May/June 2020 •August 2020

Time Series Plots Example: Non -Process Wastewater and
Stormwater
100,000
TotaITable 3+ Concentration (ng/L)
10,000
1,000
100
10
Total Table 3+ Concentrations Stormwater and Non -Contact Cooling Water
Location 1 Location 7A Location 9 Location 10A Location 12 Location 13 Location 14 Location 15 Location 21A
•April 2019 (June 2019 August 2019 ■October 2019 • December 2019 January2020 ■April 2020 ■May/June 2020 ■August 2020
More variability for
non -process wastewater
and stormwater
locations, particularly
during the wet event
(May/June 2020)
Chemours'M

Statistical Analysis: Wilcoxon Rank Sum Test
• Non -parametric test appropriate for small sample sizes that are not
normally distributed
• Evaluated if the distributions of total EPA Method 537 PFAS and/or total
Table 3+ PFAS concentrations at each location were statistically different
than those at Location 1
• Tests were conducted at the 5% level of significance, i.e., a = 0.05.
Chemours-

Statistical Analysis: Results
Results support to continue analyzing EPA
Method 537 at the intake river water at
Location 1 and Location 20 only
Location Category
EPA 537M PFAS Statistical
Assessment Outcome
Table 3+ PFAS Statistical
Assessment Outcome
Non-Chemours Process Wastewater
Not Different or Lower than Intake
Not Different or Lower than
Intake*
Non -Contact Cooling Water
Not Different than Intake
Not Different than Intake
Stormwater
Not Different than Intake
Greater than Intake
Stormwater-NCCW
Not Different than Intake
Some Greater than Intake
(stormwater from Monomers
IXM)
Wastewater Treatment Plant
Not Different than Intake**
(influent and effluent only)
Greater than Intake
Combined Flows to
Outfall 002
Not Different than Intake
Greater than Intake
(WWTP and stormwater)
* Location 23B concentrations were initially higher than the intake river water but have declined and been similar to the intake since January 2020. Flows from Location 23B
discharge to the Terracotta pipe which was decommissioned in 2021.
** Wastewater treatment plant influent and effluent EPA Method 437 concentrations were not statistically different or higher from the intake, but an upstream location (23A)
in the Terracotta pipe did have elevated EPA 537M concentrations. This source to the wastewater treatment has been removed due to the decommissioning of the Terracotta
pi e 2021.
it�nemours_

Review of Recent Site Work
• The Terracotta pipe was decommissioned in April 2021
• Reconfiguration of Kuraray process wastewater lines to WWTP due
to decommissioning of Terracotta pipe
• Stormwater flows from Monomers/IXM have been separated from
NCCW and are being treated by the Stormwater Treatment System
(SWTS)
• Stormwater from Monomers/IXM is being monitored as a part of the
SWTS Sampling Plan and eventually under the NPDES permit
Chemours-

P11(d) Recommendations: Monomers IXM Area
P11(c) Locations
21B is currently
inactive
4
.atR-i 1
24A, 24B, and 24C
currently combined
into NCCW pipe
10 represented
by SWTS
monitoring
1 �4 VO 4
1OA• 4t
Locations 9 and 10A currently
comprise NCCW only
Represents combined
NCCW from 9, 10A,
24A, 24B, and 24C
SW being treated and
monitored at the SWTS
• Prior stormwater and
NCCW samples were not
representative of the
entire source area
• New sample point
reflects the combined
NCCW from
Monomers/IXM
• Stormwater from
Monomers/IXM being
monitored up to 4 times a
month as a part of the
SWTS Sampling Plan
Recommendation: Replace Locations 9, 10, 10A, 24A, 246, and 24C with
one new sample location (9A) representing the combined NCCW
Chemou

Conclusions and Recommendations from WWTP
Assessment
• Largest contributors of PFAS were sanitary wastewater flows and desorption
of PFAS from biosolids in the waste activated sludge in the WWTP
• Recommendations
— Washing machine effluent from Monomers IXM and PPA to be directed to offsite disposal
(in progress)
— Downsize existing system and reduce biosolids volume (in progress)
— Continue air emission abatement controls (ongoing)
— Wash and rinse DuPont lab sump (complete)
• Other actions completed associated with the WWTP
— Terracotta pipe grouted in April 2021
— Overall flows decreased due to WWTP modifications
Chemours-

P11(d) Recommendations: WWTP
P11(c) Locations
642.A3
2B
18
Kurarayand DuPont
locations do not
contribute PFAS
concentrations greater
than Location 1
23A and 23B no
longer conveying
water
ti19A,
1 9 B -
22
P11(d) Locations
am
ICIFY x1C11-0 rx�
Continue sampling
WWTP influent at
Location 22
• The Terracotta pipe has
been replaced and
sources of PFAS to the
WWTP have been
assessed
• Continuing to sample
influent and effluent
maintains continuity of
monitoring of the WWTP
Recommendation: Replace locations representing inputs to the WWTP (Locations 6A, 66,
18, 19A, 196, 23A, 236) with ongoing sampling of the WWTP influent (Location 22)
Chemours

P11(d) Recommendations: Stormwater
Continue sampling
SW at Location 7A
P11(d) Locations
8 ALL,
7Ar`
Recommendation: Replace
stormwater-only Locations 2, 3, 4,
and 5 with ongoing sampling of
downstream Location 7A.
Total Table 3+ Concentration (ng/L)
1,000
10 -
Location 1 Location 7A
Increased
concentration at
7A during wet
events
represent
stormwater

Proposed P11 Sampling Plan
Locations: After August 2021
• Sampling locations in
Monomers/IXM area
representative of the
separated NCCW (Location
9A) and stormwater (SWTS)
• Continued WWTP influent
and effluent monitoring
(Locations 8 and 22)
• Combined stormwater from
western portion of Site
measured at Location 7A
• Locations 11 and 14 under
consideration to be
represented at Location 12
• Sample EPA Method 537 at
Locations 1 and 20 only
Chemours-

• 18 months of P11(c) sampling identified sources of PFAS in process
wastewater, non -process water, and stormwater
• Recommendations proposed for P11(d) ongoing sampling program to
streamline sample locations and represent recent site work
• Request approval for these changes to implement during August 2021
bimonthly sampling event
Chemours-

Questions?
Chemours-