2022.02.01_CCO.p19-24_ChemoursDrinkingWaterSamplingPlan-V1-LCFRcounties

Interim Four Counties Sampling and
Drinking Water Plan (New Hanover,
Brunswick, Columbus and Pender Counties)
Chemours Fayetteville Works

Prepared for
The Chemours Company FC, LLC
22828 NC Highway 87 Fayetteville, NC 28306

Prepared by
Geosyntec Consultants of NC, PC
2501 Blue Ridge Road, Suite 430
Raleigh, NC 27607

Project Number TR0795A

February 1, 2022

TR0795A – Interim Four Counties Sampling and Drinking Water Plan, Chemours Fayetteville Works i February 2022
TABLE OF CONTENTS
1.0 INTRODUCTION ....................................................................................................... 2
1.1 Four Counties Sampling and Drinking Water Plan Workflow .................................... 2
2.0 PRIVATE WELL SAMPLING ................................................................................... 6
2.1 Step 1A – Initial Sampling ........................................................................................... 6 2.1.1 Call Center ................................................................................................... 6 2.1.2 Resampling of Private Wells in New Hanover ............................................ 6 2.1.3 Private Well Owner/Resident Sampling Requests ....................................... 6
2.2 Step 1B - Compilation of Private Well and Other Supporting Information ................ 7
2.3 Step 2 - Systematic Sampling of Private Wells ........................................................... 8 2.3.1 Systematic Sampling Approach ................................................................... 9 2.3.2 Provision of Sampling Results ................................................................... 10
3.0 INTERIM REPLACEMENT OF PRIVATE DRINKING SUPPLIES ..................... 11
3.1 Bottled Water and Letter Delivery ............................................................................. 11
3.2 Bottled Water Voucher Card...................................................................................... 11
4.0 SCHEDULE AND REPORTING .............................................................................. 12
5.0 REFERENCES........................................................................................................... 13
LIST OF TABLES
Table 1 Attachment C PFAS Compounds
Table 2 Summary of Data Needs
LIST OF FIGURES
Figure 1 Four Counties Sampling and Drinking Water Plan Workflow Diagram
Figure 2 Private Well Systematic Sampling Workflow Diagram
LIST OF APPENDICES
Appendix A Private Drinking Water Well Sampling Procedures
Appendix B Investigative Areas by County and List of Additional Analytes

TR0795A – Interim Four Counties Sampling and Drinking Water Plan, Chemours Fayetteville Works 1 February 2022
ACRONYMS AND ABBREVIATIONS
ASR Aquifer Storage and Recovery
CFPUA Cape Fear Public Utility Authority
CFRW Cape Fear River Watch
HFPO-DA hexafluoropropylene oxide dimer acid
IA investigative area
LCFWASA Lower Cape Fear Water & Sewer Authority
NCDEQ North Carolina Department of Environmental Quality
ng/L nanograms per liter
PFAS per- and polyfluoroalkyl substances

TR0795A – Interim Four Counties Sampling and Drinking Water Plan, Chemours Fayetteville Works 2 February 2022
1.0 INTRODUCTION
This Interim Four Counties Sampling and Drinking Water Plan has been prepared by Geosyntec
Consultants of NC, P.C. (Geosyntec) for The Chemours Company FC, LLC (Chemours). This
document presents an interim plan for sampling private wells and implementing mitigation
measures in New Hanover, Brunswick, Columbus, and Pender Counties (the counties) of North
Carolina.
In a letter from the North Carolina Department of Environmental Quality (NCDEQ) on 3
November 2021 (NCDEQ, 2021), NCDEQ requested that Chemours submit an updated Drinking
Water Compliance Plan pursuant to Paragraph 24 of the Consent Order between Chemours,
NCDEQ, and Cape Fear River Watch (CFRW), which was entered by the Court on 25 February
2019. In this letter, NCDEQ also requested that the updated Drinking Water Compliance Plan
include a sampling plan for drinking water wells in the counties and provide replacement drinking
water to qualifying parties. To address these requests from NCDEQ, this Interim Sampling and
Drinking Water Plan has been prepared specifically for the four counties.
NCDEQ also posted to their website1 on 3 November 2021 per- and polyfluoroalkyl substances
(PFAS) data from groundwater samples collected from NCDEQ and Cape Fear Public Utility
Authority (CFPUA) public supply wells between 2019 and 2021. These data were supplemented
with additional PFAS data from groundwater samples collected from different wells, including
private, public supply and emergency wells, which were provided to Chemours on behalf of
NCDEQ via email on 5 December 2021.
1.1 Four Counties Sampling and Drinking Water Plan Workflow
The Drinking Water Compliance Plan for the area surrounding the Fayetteville Works Facility
(Facility; Parsons, 2019) was developed to identify private wells with Consent Order Attachment
C PFAS (Attachment C PFAS; Table 1) from Facility air emissions and provide a replacement
drinking water supply. As such, not all elements of the Drinking Water Compliance Plan, including
the sampling design, are relevant to the private wells in the four specified counties. As a result, a
Sampling and Drinking Water Plan specific to the four counties is needed to fulfill the request
from NCDEQ; however, there is currently very limited information about the four counties.
The PFAS analytical results provided by NCDEQ included only 11 private wells in New Hanover
County2. NCDEQ provided PFAS data from a single well in Brunswick County and no PFAS
analytical data from any wells in Pender County or Columbus County. The counties encompass an

1 https://deq.nc.gov/dwr-gwr-lcfr-pfas-data-2019-2021
2 Total Attachment C PFAS concentrations in private wells were reported by NCDEQ to range from concentrations below detection limits at three sampling locations to a maximum value of 380 nanograms per liter (ng/L) at one location, which was not on a residential property. Only 2 out of the 11 private wells sampled in New Hanover County were identified to be on residential property, and total Attachment C PFAS were below the detection limits for one private well and 250 ng/L for the other private well.

TR0795A – Interim Four Counties Sampling and Drinking Water Plan, Chemours Fayetteville Works 3 February 2022
area of over 2,900 square miles, and the number of private wells and their distribution across the
counties, as well as overlay with existing utilities, is currently being investigated. The potential
source and cause of Table 3+ PFAS3 contamination in the counties is also being investigated
pursuant to the Framework to Assess Table 3+ PFAS in New Hanover, Brunswick, Columbus, and
Pender Counties (Soil and Groundwater Assessment Framework; Geosyntec, 2022), which has
been submitted under separate cover.
To fulfill the 3 November 2021 request from NCDEQ while gathering information for each of the
counties, a workflow has been developed as shown in Figure 1.

This workflow includes four steps:
• Step 1A: Initial sampling, including resampling of the 11 private wells that were
included in the data provided by NCDEQ, and sampling of requested private wells via
the call center, if eligible (Sections 2.1.3 and 3.0)
• Step 1B: Data gathering, including compilation of private well and other supporting
information (Section 2.2)
• Step 2: Systematic sampling of private wells in each of the four counties, if
necessary, based on results of Steps 1A and 1B (Sections 2.3 and 3.0)
• Step 3: Data evaluation
• Step 4: Preparation of an Updated Four Counties Sampling and Drinking Water
Plan
Steps 1A, 1B, and 2 represent the scope associated with this Interim Four Counties Sampling and
Drinking Water Plan presented in this document. Steps 1A and 1B will occur simultaneously,
where initial sampling will be completed during the data gathering stage. During the initial

3 Table 3+ PFAS are often attributed to operations at the Chemours Fayetteville Works Site and include the Attachment C PFAS (Geosyntec, 2021).

TR0795A – Interim Four Counties Sampling and Drinking Water Plan, Chemours Fayetteville Works 4 February 2022
sampling, eligible residents who call to request sampling via the call center will be scheduled for
private well testing in addition to the resampling of the 11 private wells sampled by NCDEQ.
Based on the results of Steps 1A and 1B, Step 2 will include selecting and sampling of additional
private wells in each county using a systematic sampling design.
For the private wells sampled during this Interim Sampling and Drinking Water Plan (i.e., Steps
1A and 2), a voucher card will be offered as an interim drinking water replacement if Attachment
C PFAS concentrations exceed the criteria outlined in Paragraphs 19 and 20 of the Consent Order4.
Next, Step 3 will include an evaluation of the private well sampling data in conjunction with the
data gathered from the Soil and Groundwater Assessment Framework (Geosyntec, 2022). Step 4
will incorporate findings from the two programs to develop an updated Four Counties Sampling
and Drinking Water Plan.
Table 1 Attachment C PFAS Compounds
Common Name Chemical Name CASRN Chemical Formula

HFPO-DA1 Hexafluoropropylene oxide dimer acid 13252-13-6 C6HF11O3
PEPA Perfluoro-2-ethoxypropionic acid 267239-61-2 C5HF9O3
PFECA-G Perfluoro-4-isopropoxybutanoic acid 801212-59-9 C12H9F9O3S
PFMOAA Perfluoro-2-methoxyacetic acid 674-13-5 C3HF5O3
PFO2HxA Perfluoro-3,5-dioxahexanoic acid 39492-88-1 C4HF7O4
PFO3OA Perfluoro-3,5,7-trioxaoctanoic acid 39492-89-2 C5HF9O5
PFO4DA Perfluoro-3,5,7,9-tetraoxadecanoic acid 39492-90-5 C6HF11O6
PMPA Perfluoro-2-methoxypropionic acid 13140-29-9 C4HF7O3
PFO5DA Perfluoro-3,5,7,9,11-pentaoxadodecanoic acid 39492-91-6 C7HF13O7
PS Acid Ethanesulfonic acid, 2-[1-[difluoro[(1,2,2-trifluoroethenyl)oxy]methyl]-1,2,2,2-
tetrafluoroethoxy]-1,1,2,2-tetrafluoro-
29311-67-9 C7HF13O5S

4 Any single Attachment C PFAS compound is greater than or equal to 10 nanograms per liter (ng/L), the sum of the Attachment C PFAS compounds is greater than or equal to 70 ng/L, or hexafluoropropylene oxide dimer acid (HFPO-DA) is greater than equal to 140 ng/L.

TR0795A – Interim Four Counties Sampling and Drinking Water Plan, Chemours Fayetteville Works 5 February 2022
Common Name Chemical Name CASRN Chemical Formula

Hydro-PS Acid Ethanesulfonic acid, 2-[1-[difluoro(1,2,2,2-tetrafluoroethoxy)methyl]-1,2,2,2-
tetrafluoroethoxy]-1,1,2,2-tetrafluoro-
749836-20-2 C7H2F14O5S
PFHpA1 Perfluoroheptanoic acid 375-85-9 C7HF13O2
Notes:
1 HFPO-DA and PFHpA can be analyzed under methods Table 3+ Standard Operating Procedure (SOP) and Environmental Protection Agency (EPA) Method 537 Mod.
CASRN - Chemical Abstract Service Registry Number

TR0795A – Interim Four Counties Sampling and Drinking Water Plan, Chemours Fayetteville Works 6 February 2022
2.0 PRIVATE WELL SAMPLING
2.1 Step 1A – Initial Sampling
Initial sampling (Step 1A) will be completed in conjunction with the data gathering stage (Step
1B). For the duration of the data gathering step, initial sampling efforts will include resampling of
the 11 private wells sampled by NCDEQ, and sampling of requested private wells, if eligible.
Private well sampling will be completed by Chemours subcontractor Parsons of NC (Parsons)
using procedures outlined in Appendix A. Data collected during a sampling team visit will be
uploaded to the project database. A voucher card will be offered to qualifying residents as an
initial interim replacement to private drinking water supply in accordance with procedures in
Section 3.0.
2.1.1 Call Center
An information call line will be activated by Chemours by 15 February 2022. This call line will
be used to answer questions about the activities covered in this plan and for residents to request
sampling of their private wells. Residents can call [phone] at any time to leave a message
requesting additional well sampling information or to leave questions about any step in the interim
drinking water replacement process. Messages to the call line are monitored during regular
business hours (Monday through Friday, 9am to 5pm). Calls requiring follow-up are usually
returned within 24 to 48 hours starting on the next business day.
2.1.2 Resampling of Private Wells in New Hanover
As part of the initial sampling step, Chemours will resample the 11 private wells sampled by
NCDEQ to confirm the Attachment C PFAS analytical results. Based on the analytical results, if
a resident qualifies for interim replacement drinking water, then a voucher card will be provided
(see Section 3.0).
2.1.3 Private Well Owner/Resident Sampling Requests
For residents that request sampling via the call center (Section 2.1.1), Chemours will sample the
private well if the following conditions are satisfied:
• The private well is the primary source of drinking water on the property, and
• The private well is located within half mile of Cape Fear River5, or
5 As described in the Soil and Groundwater Assessment Framework (Geosyntec, 2022), Cape Fear River water
withdrawals and usage may potentially be responsible for Table 3+ PFAS detected in samples collected by NCDEQ. One hypothesis identified in the framework is Table 3+ PFAS originating from aquifer recharge by Cape Fear River including recharge in Floodplain areas.
TR0795A – Interim Four Counties Sampling and Drinking Water Plan, Chemours Fayetteville Works 7 February 2022
•The private well is within a public water service area and/or sanitary sewer networks6
Based on the analytical results, if a resident qualifies for interim replacement drinking water, then
a voucher card will be provided (see Section 3.0).
2.2 Step 1B - Compilation of Private Well and Other Supporting
Information
Prior to the development of the systematic sampling of private wells, a data gathering stage will
be conducted to compile existing/available information. The objective of the data gathering stage
is to identify:
1.Additional private wells for systematic sampling (i.e., private wells to be considered
for selection and sampling in Step 2).
2. Potential areas to focus the systematic sampling design.
Table 2 summarizes the specific data needs by objective, which will be a starting point, but
additional data needs may be identified throughout the scope of this Interim Four Counties
Sampling and Drinking Water Plan. Geosyntec has begun compiling some of the required
information from publicly available sources. Other required information is presently in possession
of other organizations such as NCDEQ, the counties and various utilities. In response to the
NCDEQ letter, Geosyntec has sent letters to these organizations requesting this information and a
teleconference to discuss these data requests. Receipt of information requested from the NCDEQ
and other organizations is currently pending.
The first data gathering objective is to identify potential additional private wells for systematic
sampling in each county. Locations of the identified private wells will be mapped and overlain
with public water and sewer distribution6 and residential parcel data to understand their spatial
distribution across each county. Data on public water usage, as available, will also be used to
determine the primary source of drinking water at each residential property (i.e., public water vs.
private well) so that private well users are considered for sampling.
The second data gathering objective is to identify potential areas in each county to be prioritized
for sampling. This will be achieved through collection of data in conjunction with the Soil and
Groundwater Assessment Framework (Geosyntec, 2022).
The data gathering stage is anticipated to last up to six months depending upon the responsiveness
of the various parties that are in possession of necessary data. Once the data gathering stage has
been completed, the compiled information along with the results of any initial private well
sampling within the four counties will be used to develop the systematic sampling plan for the
counties.
6 As described in the Soil and Groundwater Assessment Framework (Geosyntec, 2022), one hypothesis being evaluated is Table 3+ PFAS originating from leaks in water distribution and sanitary sewer lines. If during the
assessment this hypothesis is refined or not supported, then this criterion will be changed accordingly.
TR0795A – Interim Four Counties Sampling and Drinking Water Plan, Chemours Fayetteville Works 8 February 2022
Table 2 Summary of Data Needs
Data Needs Objective
Residential parcels, tax detail data, and building footprint in digital form 1
A consolidated list containing private well location information (such as eastings, northings, address and/or tax parcels), well owner, elevations, screen interval depths, and hydrogeological data (including, without limitation, start and end depth of each hydrogeological unit)
1
Digital computerized map of potable water distribution networks 1
Database of residences using public water, i.e., not using private well as the primary
source of drinking water 1
Records regarding the numbers, locations, registrations, usages, and well service and operation histories of private and public drinking water supply wells 1
Any data (and relevant information, including but not limited to laboratory EDDs and sample collection information, etc.) indicating the presence of PFAS in water sources
2
Data about water distribution system leaks since 1979 (including known water mains with leaks, and leak and repair locations)
2
Information since 1979, on a per year basis, of the proportion of Cape Fear River water versus groundwater or other water sources used in each distribution system
2
Locations where surface water from the Cape Fear River was injected into subsurface aquifers
2
List of parties permitted to draw Cape Fear River water since 1979 (NCDEQ) 2
Records of customers of Lower Cape Fear Water & Sewer Authority (LCFWASA), Aqua of NC, Inc., Cape Fear Public Utility Authority (CFPUA), and other utilities 2
Identification of golf courses, cemeteries and parks irrigating lawns using water sourced from the Cape Fear River 2
Identification of farmland practices and locations using Cape Fear River water for
irrigation 2
Records of Aquifer Storage and Recovery (ASR) program (volumes injected, dates operational, etc.) 2
2.3 Step 2 - Systematic Sampling of Private Wells
Upon completion of Steps 1A and 1B (anticipated to last up to six months depending upon the
responsiveness of the various parties), Chemours will proceed with Step 2: the systematic sampling
of private wells in the counties. The following subsections provide details on the systematic
sampling approach and provision of sample results.

TR0795A – Interim Four Counties Sampling and Drinking Water Plan, Chemours Fayetteville Works 9 February 2022
2.3.1 Systematic Sampling Approach
As part of the systematic sampling program, up to 200 private wells may be sampled from each
county, as described below.
A systematic sampling approach of private wells will be undertaken using the information
compiled during the initial sampling and the data gathering steps. This systematic approach allows
for selection and sampling of private wells and is anticipated to result in a relatively uniform
distribution of wells across the extent of each county to assess the presence of Attachment C
constituents. This will help in defining any future sampling efforts, if needed, that can be focused
in the potentially impacted areas. An overview of this systematic approach is provided in Figure
2.

Figure 2 Private Well Systematic Sampling Workflow Diagram
Counties have been subdivided into investigative areas (IAs; see Appendix B). The IAs shown in
Figures B.1 to B.4 are based on Geosyntec’s current understanding of the public water distribution
networks and/or service areas and may be updated as additional information is obtained through
Steps 1A and 1B. The boundaries of the IAs in Figures B.1 to B.4 were determined based on the
extent of known public water service areas in each county, while the size of each IA was
proportionally selected to capture the density and distribution of the residential parcels.
Each IA will then be further subdivided into subareas based on information obtained through Steps
1A and 1B. In each subarea, a target number of private wells will be sampled, and metadata (for
example, well depth) will be collected from these wells. The number of private wells to be sampled
will be proportionally weighted to the size of each subarea, density of private wells, and proximity
to potential features of interest. Other factors may be considered in the determination of the sample
size in each subarea based on the findings from the data gathering and initial sampling results.
Sampling will continue in each county until up to 200 private wells have been sampled. All
samples collected will be analyzed for Attachment C PFAS compounds (Table 1) and may also be

TR0795A – Interim Four Counties Sampling and Drinking Water Plan, Chemours Fayetteville Works 10 February 2022
analyzed for other parameters (e.g., other PFAS, other contaminants, other water quality
parameters, etc.) such as those listed in Appendix B.
Private well sampling will be completed by Chemours subcontractors Parsons using procedures
outlined in Appendix A. Data collected during a sampling team visit will be uploaded to the project
database. A voucher card will be offered to qualifying residents as an interim replacement to
private drinking water supply in accordance with procedures in Section 3.0.
2.3.2 Provision of Sampling Results
On an ongoing basis and within seven days of receipt of final laboratory results, Chemours will
provide new groundwater sampling results to NCDEQ, with samples identified by both address
and sample identification code. In addition, within seven days of receipt of final laboratory results,
Chemours will also provide the results in the form of a certified summary certificate to the party
who had their well tested. Results may also be provided to the individual counties or other state
and local government agencies.
Correspondence will be sent to each well owner providing them with their sampling results for
Attachment C PFAS compounds. If analyzed for additional compounds (Appendix B), a separate
letter will be sent which will include the laboratory analytical report. If the residents have any
questions regarding results of the analytical results, they can contact their local health department
or NCDEQ. Parsons may also attempt to hand deliver returned letters. For parties represented by
legal counsel, communications will be made through counsel.

TR0795A – Interim Four Counties Sampling and Drinking Water Plan, Chemours Fayetteville Works 11 February 2022
3.0 INTERIM REPLACEMENT OF PRIVATE DRINKING SUPPLIES
As discussed in Section 1.1, bottled water and a voucher card will be offered as an interim drinking
water replacement if the Attachment C PFAS concentrations in the private wells sampled during
the Interim Sampling and Drinking Water Plan exceed the criteria outlined in Paragraphs 19 and
20 of the Consent Order7.
3.1 Bottled Water and Letter Delivery
Upon notification that a resident qualifies for replacement drinking water, Chemours
representatives (Parsons) will provide initial replacement drinking water within 5 days by visiting
the residence and delivering up to one month’s supply of bottled water along with a letter
explaining the path forward for interim bottled water. If the team is not able to deliver the initial
replacement drinking water, a scheduler will attempt to call the resident and make an appointment
for the team to return and make the delivery.
Water and letter delivery, as well as all delivery attempts, messages, and conversations, will be
documented in the project database.
3.2 Bottled Water Voucher Card
After bottled water and letter delivery, the resident will receive a bottled water voucher card for
purchasing drinking water. The voucher card will be preloaded with $225 for three months of
drinking water, which equates to $75 per month. This card is only to be used for purchasing bottled
water. Residents will receive detailed voucher card instructions, customer service contact
information, and the Chemours Call Line phone number, along with the voucher card.

7 Any single Attachment C PFAS compound is greater than or equal to 10 nanograms per liter (ng/L), the sum of the Attachment C PFAS compounds is greater than or equal to 70 ng/L, or hexafluoropropylene oxide dimer acid (HFPO-DA) is greater than equal to 140 ng/L.

TR0795A – Interim Four Counties Sampling and Drinking Water Plan, Chemours Fayetteville Works 12 February 2022
4.0 SCHEDULE AND REPORTING
Sample results will be provided to each resident and to NCDEQ when final data are available.
Information is provided to the resident via mail, and to the property owner when Chemours is
made aware that the resident is not the owner. Residents who are not the property owner will
receive notification indicating eligibility and will be offered interim replacement drinking water
(if applicable).
Quarterly reports documenting the implementation of the Interim Four Counties Sampling and
Drinking Water Plan will be submitted to NCDEQ. These quarterly reports will include summaries
of the sampling activities completed and the residents who are eligible for interim replacement
drinking water. These quarterly reports may be submitted separately to NCDEQ or will be included
as a separate section in the current quarterly report that is required under Paragraph 28 of the CO.
Chemours will also provide notification to NCDEQ (as requested) via email of each resident that
declines interim replacement drinking water within seven days or as soon as practicable thereafter
of the resident declining. The notification will include the names, addresses, and contact
information for all the residents who have declined. Because the quarterly reports are public
documents and, as such, should not include private contact information of residents, Chemours
will provide this information (i.e., names, addresses, and contact information for all the residents
who have declined) in a separate report on a quarterly basis.

TR0795A – Interim Four Counties Sampling and Drinking Water Plan, Chemours Fayetteville Works 13 February 2022
5.0 REFERENCES
Geosyntec Consultants of NC, P.C. 2021a. Response to NCDEQ Comments on Consent Order
Paragraph 18 On and Offsite Assessment Report. June 14, 2021.
Geosyntec Consultants of NC, P.C. 2022. Framework to Assess Table 3+ PFAS in New Hanover,
Brunswick, Columbus and Pender Counties: Chemours Fayetteville Works.
February 1, 2022.
NCDEQ. 2021. “Re: Notice Regarding Chemours’ Obligations Under Consent Order and 15A
NCAC 02L .0106 – Offsite Groundwater Assessment and Provision of Replacement Drinking
Water Supplies.” North Carolina Department of Environmental Quality, Assistant Secretary
for the Environment. November.
Parsons. 2019. Drinking Water Compliance Plan: Chemours Fayetteville Works. April.

TR0795A – Interim Four Counties Sampling and Drinking Water Plan, Chemours Fayetteville Works
Appendix A
Private Drinking Water Well Sampling
Procedures

TR0795A – Interim Four Counties Sampling and Drinking Water Plan, Chemours Fayetteville Works 1
APPENDIX A
PRIVATE DRINKING WATER WELL SAMPLING PROCEDURES
The purpose of this appendix is to describe the general sampling procedures to be used for private
well sampling as outlined in the Interim Drinking Compliance Plan.
Sampling Notification and Documentation
To conduct the sampling, Chemours subcontractor representatives (Parsons of NC) will go to the
identified residence, knock on the door, and deliver a notification letter from Chemours. The
notification letter (i) describes the private well sampling program; (ii) requests the resident’s
participation if applicable; and (iii) includes a phone number that the resident can call to request
information about the program and/or to schedule sampling of their private well. Notifications and
responses to notifications (e.g., accept or decline) will be documented on electronic field forms.
If the resident is at home and accepts the offer to have their private well sampled, then the resident
can choose to either have the sample collected at that time or reschedule sampling for a later time.
If the resident declines the offer of sampling, then the decline will be noted in the electronic field
form.
If no one is home, the sampling team will leave the notification letter in a prominent location and
the notification will be noted in the electronic field form.
For residents that either have not called to request sampling or whose residence was inaccessible,
Chemours subcontractor representatives will attempt to make contact again via a mailed letter sent
after the initial visit. The mailed letter will again offer sampling of private wells. If needed, the
project team may also make a return visit to the residence to deliver another copy of the notification
letter. If no communication is received from the resident after the letter is mailed, follow-up letters
will be sent each quarter for the next three quarters (a total of 4 letters will be mailed to the
resident).
Chemours subcontractor representatives will maintain a database that includes addresses, the dates
and status of attempts to contact each resident, resident’s contact information (name, mailing
address, phone number), sampling completed, and any declines of the offer to sample.
Sample Collection Methodology
The procedure for sampling private wells is as follows:
1.Record available information about the resident (name, contact number, etc.), the
property owner, and the well (well age, depth, construction history, presence/location
of any filters or other systems, etc.).
2.Don a new pair of powderless, disposable nitrile (or similar) gloves for each sample
being collected.
3.Find the spigot closest to the well head.
Appendix A
Private Drinking Water Well Sampling Procedures
TR0795A – Interim Four Counties Sampling and Drinking Water Plan, Chemours Fayetteville Works 2
4.Turn on water at the selected spigot and purge the well until the pump turns on (usually
approximately 5 to 10 minutes).
5.Hold the high-density polypropylene sampling bottle by the body. Do not touch or
handle the bottle by the neck and mouth. Remove the bottle cap and do not set it down
at any point, place the bottle under the spigot, and fill completely. Do not allow the
neck or the mouth of the bottle to touch the spigot. Do not use a secondary container
to fill the bottle.
6.Recap the sample bottle and secure cap completely.
7.Affix a pre-printed sample label to the bottle (unless already affixed by the laboratory).
If the label is not pre-printed, fill out relevant sample information on the label.
8.Place the sample in a cooler of wet ice or in cold storage for future shipping.
9.Record the sample name, date, and time in the electronic field form.
10.Complete the chain of custody form(s), secure the cooler, and ship the samples to the
analytical laboratory.
11.Information related to collection of each private well sample will be recorded on an
electronic data collection form. Drinking water will be sampled directly from the well
head (or as close as possible) at private wells. To ensure against cross-contamination
between drinking water sampling locations, the sampler collecting the samples will
wear clean, disposable latex and/or nitrile gloves and limit his/her contact with the
samples. Sample bottles and containers appropriate for PFAS analysis will be prepared
by the contracted laboratory and will be sealed to ensure cleanliness. Sample bottles
will not be cleaned or reused in the field.
Preservation and Handling of Samples
Each containerized sample will be labeled and placed as soon as possible into an insulated sample
cooler, which will serve as a shipping container. Wet ice will be placed in the sample containers
within heavy-duty plastic bags. Samples will be maintained at a cool temperature (optimum 4°C
 2°C) from the time of collection until the coolers arrive at the laboratory (if required). Plastic
“bubble wrap” and/or polystyrene foam may also be used to protect the samples during shipping.
Prior to shipment of the samples to the laboratory, a chain of custody form will be completed by
the sample team. Sample locations, sample identification numbers, description of samples, number
of samples collected, and specific laboratory analyses to be run on each sample will be recorded
on the chain of custody form.
TR0795A – Interim Four Counties Sampling and Drinking Water Plan, Chemours Fayetteville Works 3
Appendix A
Private Drinking Water Well Sampling Procedures

Quality Assurance/Quality Control
Associated quality control samples as required by the laboratory/analytical method will be
collected and analyzed throughout the duration of the project. These may include field duplicates,
matrix spikes/duplicates, and field blanks.
TR0795A – Interim Four Counties Sampling and Drinking Water Plan, Chemours Fayetteville Works
Appendix B
Investigative Areas by County and List of
Additional Analytes
Investigative Areas in New Hanover County
Chemours Fayetteville WorksNorth Carolina
Figure
B.1RaleighFebruary 2022
Projection: NAD83 North Carolina ftUS; Units in Foot US
Notes:* Data provided by NCDEQ indicates a Table 3+ value of 0 ng/L at these locations.1. Public and Private well data provided by The North Carolina Department of Environmental Quality (NCDEQ) on November and December 2021.2. Public Water Service Areas for the Towns of Carolina Beach, Kure Beach, and Wrightsville Beach was downloaded from The Drinking Water Resilience Interactive Project (DRIP) site (http://drip.unctv.org/maps/maps-051716/).3. Water service areas for the Monterey Heights Groundwater, Sweeney Treatment Plant, and Richardson Nano Filtration from Cape Fear Public Utility Authority (CFPUA) site was downloaded from ArcGIS Online Feature service(https://services.arcgis.com/UfH3YtFuVFnIN4Zz/ArcGIS/rest/services/Water ServiceArea/FeatureServer/0).4. Cape Master Water System is based on North Carolina Water Quality Report (https://www.ncwaterquality.com/media/The-Cape-2021-Flushing-Master-Maps.pdf).5. County Boundaries was downloaded from OneMap site(https://www.nconemap.gov).6. The outline of the River shown on this figure is approximate (River outline basedon compilation of open data sources from ArcGIS online service and North Carolina Department of Environmental Quality Online GIS - Major Hydro shapefile).7. Basemap source: Esri, HERE, Garmin, (c) OpenStreetMap contributors, and the GIS user community.
1
2
5
4
3
BRUNSWICK
PENDER
COLUMBUS
BLADEN Legend
Private Well Sampling Locations (Detected)
Private Well Sampling Locations (Non-detect)*
NCDEQ PFAS Sampling Locations (Detected)
NCDEQ PFAS Sampling Locations*
")#Investigative Area Identifier
Investigative Areas (Tentative; May change asadditional information is gathered)
Cape Fear River
County Boundary
Surrounding North Carolina County
New Hanover County Public Water Service Areas
Town of Carolina Beach
Town of Kure Beach
Town of Wrightsville Beach
Monterey Heights Groundwater
Sweeney Treatment Plant
Richardson Nano Filtration
Cape Master
³
4 0 42 Miles
Investigative Areas in Brunswick County
Chemours Fayetteville WorksNorth Carolina
Figure
B.2RaleighFebruary 2022
Projection: NAD83 North Carolina ftUS; Units in Foot US
Notes:1. Public and Private well data provided by The North Carolina Department of Environmental Quality (NCDEQ) on November and December 2021.2. Public Water Service Area was downloaded from The Drinking Water Resilience Interactive Project (DRIP) site (http://drip.unctv.org/maps/maps-051716/).3. County Boundaries was downloaded from OneMap site (https://www.nconemap.gov).4. The outline of the River shown on this figure is approximate (River outline basedon compilation of open data sources from ArcGIS online service and North Carolina Department of Environmental Quality Online GIS - Major Hydro shapefile).5. Basemap source: Esri, HERE, Garmin, (c) OpenStreetMap contributors, and the GIS user community.
1
2
3
4
5
BRUNSWICK
COLUMBUS
PENDER
BLADEN Legend
Public Water Supply Water Source
")#Investigative Area Identifier
Investigative Areas (Tentative; May change asadditional information is gathered)
Cape Fear River
County Boundary
Surrounding North Carolina County
Brunswick County Public Water Service Areas
NWWTP Service Area
211 WTP Service Area
³
4 0 42 Miles
Investigative Areas in Columbus County
Chemours Fayetteville WorksNorth Carolina
Figure
B.3RaleighFebruary 2022
Projection: NAD83 North Carolina ftUS; Units in Foot US
Notes:1. Public and Private well data provided by The North Carolina Department of Environmental Quality (NCDEQ) on November and December 2021.2. Public Water Service Area was downloaded from The Drinking Water Resilience Interactive Project (DRIP) site (http://drip.unctv.org/maps/maps-051716/).3. County Boundaries was downloaded from OneMap site (https://www.nconemap.gov).4. The outline of the River shown on this figure is approximate (River outline basedon compilation of open data sources from ArcGIS online service and North Carolina Department of Environmental Quality Online GIS - Major Hydro shapefile).5. Basemap source: Esri, HERE, Garmin, (c) OpenStreetMap contributors, and the GIS user community.
5
43
2
1
6
COLUMBUS
BLADEN
BRUNSWICK
ROBESON
PENDER
SAMPSON Legend
Public Water Supply Water Source
")#Investigative Area Identifier
Investigative Areas (Tentative; May change asadditional information is gathered)
Cape Fear River
County Boundary
Surrounding North Carolina County
Public Water Service Areas
Columbus County WD I
Columbus County WD II
Columbus County WD III
Riegelwood Sanitary District
Tabor City
Town Of Bolton
Town of Brunswick
Town of Cerro Gordo
Town of Chadbourn
Town of Fair Bluff
Town of Lake Waccamaw
Town of Whiteville
³
4 0 42 Miles
Investigative Areas in Pender County
Chemours Fayetteville WorksNorth Carolina
Figure
B.4RaleighFebruary 2022
Projection: NAD83 North Carolina ftUS; Units in Foot US
Notes:1. Public and Private well data provided by The North Carolina Department of Environmental Quality (NCDEQ) on November and December 2021.2. Public Water Service Areas and the Public Water Supply Source were downloaded from The Drinking Water Resilience Interactive Project (DRIP) site (http://drip.unctv.org/maps/maps-051716/).3. Public Water Supply Lines was downloaded from Pender County GIS data (https://gis.pendercountync.gov/arcgis/rest/services/Layers/MapServer/50).4. County Boundaries was downloaded from OneMap site (https://www.nconemap.gov).5. The outline of the River shown on this figure is approximate (River outline basedon compilation of open data sources from ArcGIS online service and North Carolina Department of Environmental Quality Online GIS - Major Hydro shapefile).6. Basemap source: Esri, HERE, Garmin, (c) OpenStreetMap contributors, and the GIS user community.
1
2
3
4
5
PENDER
ONSLOW
DUPLIN
SAMPSON
BRUNSWICK
BLADEN
COLUMBUS
Legend
Public Water Supply Water Source
")#Investigative Area Identifier
Investigative Areas (Tentative; May change asadditional information is gathered)
Cape Fear River
County Boundary
Surrounding North Carolina County
Public Water Supply Lines
Public Water Service Areas
Maple Hill Water District
Rocky Pt/Topsail WS Dist
Town of Burgaw
Town of Surf City
Town of Topsail Beach
³
4 0 42 Miles
TABLE B.1PFAS ANALYTES Chemours Fayetteville Works, North CarolinaGeosyntec Consultants of NC, P.C.Attachment C (Table 3+ SOP and Table 6)Table 3+ (Table 3+ SOP)Other PFAS (Method 537 Mod)HFPO-DA1✔✔✔Hexafluoropropylene oxide dimer acid13252-13-6 C6HF11O3PEPA✔✔--Perfluoro-2-ethoxypropionic acid267239-61-2 C5HF9O3PFECA-G✔✔--Perfluoro-4-isopropoxybutanoic acid801212-59-9 C12H9F9O3SPFMOAA✔✔--Perfluoro-2-methoxyacetic acid674-13-5 C3HF5O3PFO2HxA✔✔--Perfluoro-3,5-dioxahexanoic acid39492-88-1 C4HF7O4PFO3OA✔✔--Perfluoro-3,5,7-trioxaoctanoic acid39492-89-2 C5HF9O5PFO4DA✔✔--Perfluoro-3,5,7,9-tetraoxadecanoic acid39492-90-5 C6HF11O6PMPA✔✔--Perfluoro-2-methoxypropionic acid13140-29-9 C4HF7O3Hydro-EVE Acid--✔--2,2,3,3-tetrafluoro-3-({1,1,1,2,3,3-hexafluoro-3-[(1,2,2,2-tetrafluoroethyl)oxy]propan-2-yl}oxy)propionic acid 773804-62-9 C8H2F14O4EVE Acid--✔--2,2,3,3-tetrafluoro-3-({1,1,1,2,3,3-hexafluoro-3-[(1,2,2-trifluoroethenyl)oxy]propan-2-yl}oxy)propionic acid69087-46-3 C8HF13O4PFECA B--✔--Perfluoro-3,6-dioxaheptanoic acid151772-58-6 C5HF9O4R-EVE--✔--Pentanoic acid, 4-(2-carboxy-1,1,2,2-tetrafluoroethoxy)-2,2,3,3,4,5,5,5-octafluoro- 2416366-22-6 C8H2F12O5PFO5DA✔✔--Perfluoro-3,5,7,9,11-pentaoxadodecanoic acid39492-91-6 C7HF13O7R-PSDA--✔-- Pentanoic acid, 2,2,3,3,4,5,5,5-octafluoro-4-(1,1,2,2-tetrafluoro-2-sulfoethoxy)- 2416366-18-0 C7H2F12O6SR-PSDCA--✔--Ethanesulfonic acid, 1,1,2,2-tetrafluoro-2-[1,2,2,3,3-pentafluoro-1-(trifluoromethyl)propoxy]- 2416366-21-5 C6H2F12O4SHydrolyzed PSDA--✔--Acetic acid, 2-fluoro-2-[1,1,2,3,3,3-hexafluoro-2-(1,1,2,2-tetrafluoro-2-sulfoethoxy)propoxy]- 2416366-19-1 C7H3F11O7SNVHOS--✔--1,1,2,2,4,5,5,5-heptafluoro-3-oxapentanesulfonic acid; or 2-(1,2,2,2-ethoxy)tetrafluoroethanesulfonic acid; or 1-(1,1,2,2-tetrafluoro-2-sulfoethoxy)-1,2,2,2-tetafluoroethane 801209-99-4 C4H2F8O4SPES--✔--Perfluoro-2-ethoxyethanesulfonic acid 113507-82-7 C4HF9O4SPS Acid✔✔--Ethanesulfonic acid, 2-[1-[difluoro[(1,2,2-trifluoroethenyl)oxy]methyl]-1,2,2,2-tetrafluoroethoxy]-1,1,2,2-tetrafluoro- 29311-67-9 C7HF13O5SHydro-PS Acid✔✔--Ethanesulfonic acid, 2-[1-[difluoro(1,2,2,2-tetrafluoroethoxy)methyl]-1,2,2,2-tetrafluoroethoxy]-1,1,2,2-tetrafluoro- 749836-20-2 C7H2F14O5SPFHpA1✔--✔Perfluoroheptanoic acid375-85-9 C7HF13O2Common NamePFAS Grouping (Method)Chemical NameCASRN Chemical FormulaTR0795APage 1 of 3February 2022
TABLE B.1PFAS ANALYTES Chemours Fayetteville Works, North CarolinaGeosyntec Consultants of NC, P.C.Attachment C (Table 3+ SOP and Table 6)Table 3+ (Table 3+ SOP)Other PFAS (Method 537 Mod)Common NamePFAS Grouping (Method)Chemical Name CASRN Chemical FormulaPFBA-- --✔Perfluorobutanoic acid 375-22-4 C4HF7O2PFPeA-- --✔Perfluoropentanoic acid 2706-90-3 C5HF9O2PFHxA----✔Perfluorohexanoic acid307-24-4 C6HF11O2PFOA----✔Perfluorooctanoic acid335-67-1 C8HF15OPFNA----✔Perfluorononanoic acid375-95-1 C9HF17O2PFDA----✔Perfluorodecanoic acid335-76-2 C10HF19O2PFUnA----✔Perfluoroundecanoic acid2058-94-8 C11HF21O2PFDoA----✔Perfluorododecanoic acid307-55-1 C12HF23O2PFTriA----✔Perfluorotridecanoic acid72629-94-8 C13HF25O2PFTeA----✔Perfluorotetradecanoic acid376-06-7 C14HF27O2PFHxDA----✔Perfluorohexadecanoic acid 67905-19-5 C16HF31O2PFODA----✔Perfluorooctadecanoic acid16517-11-6 C18HF35O2PFBS----✔Perfluorobutanesulfonic acid375-73-5 C4HF9SOPFPeS----✔Perfluoropentanesulfonic acid 2706-91-4 C5HF11O3SPFHxS----✔Perfluorohexanesulfonic acid355-46-4 C6HF13SO3PFHpS----✔Perfluoroheptanesulfonic acid375-92-8 C7HF15O3SPFOS----✔Perfluorooctanesulfonic acid1763-23-1 C8HF17SO3PFNS----✔Perfluorononanesulfonic acid68259-12-1 C9HF19O3SPFDS----✔Perfluorodecanesulfonic acid335-77-3 C10HF21O3SPFDoDS----✔Perfluorododecanesulfonic acid79780-39-5 C12HF25O3STR0795APage 2 of 3February 2022
TABLE B.1PFAS ANALYTES Chemours Fayetteville Works, North CarolinaGeosyntec Consultants of NC, P.C.Attachment C (Table 3+ SOP and Table 6)Table 3+ (Table 3+ SOP)Other PFAS (Method 537 Mod)Common NamePFAS Grouping (Method)Chemical Name CASRN Chemical Formula4:2 FTS-- --✔4:2 Fluorotelomer sulfonic acid 757124-72-4 C6H5F9O3S6:2 FTS-- --✔6:2 Fluorotelomer sulfonic acid 27619-97-2 C8H5F13SO38:2 FTS-- --✔8:2 Fluorotelomer sulfonic acid 39108-34-4 C10H5F17O3S10:2 FTS-- --✔10:2 Fluorotelomer sulfonic acid 120226-60-0 C12H5F21O3NEtFOSAA-- --✔N-ethyl perfluorooctane sulfonamidoacetic acid 2991-50-6 C12H8F17NO4SNEtPFOSA-- --✔N-ethylperfluoro-1-octanesulfonamide 4151-50-2 C10H6F17NO2SNEtPFOSAE-- --✔N-ethyl perfluorooctane sulphonamidoethanol 1691-99-2 C12H10F17NO3SNMeFOSAA-- --✔N-methyl perfluorooctane sulfonamidoacetic acid 2355-31-9 C11H6F17NO4SNMePFOSA----✔N-methyl perfluoro-1-octanesulfonamide31506-32-8 C9H4F17NO2SNMePFOSAE----✔N-methyl perfluorooctane sulfonamidoethanol24448-09-7 C11H8F17NO3SPFOSA----✔Perfluorooctane sulfonamide754-91-6 C8H2F17NO2SF-53B Major----✔Perfluoro(2-((6-chlorohexyl)oxy)ethanesulfonic acid)756426-58-1 C8HClF16O4SF-53B Minor----✔Perfluoro(2-((8-chlorooctyl)oxy)ethanesulfonic acid)763051-92-9 C10HClF20O4SDONA----✔2,2,3-Trifluoro-3-(1,1,2,2,3,3-hexafluoro-3-(trifluoromethoxy)propoxy)propanoic acid919005-14-4 C7H2F12O4Notes:1 - HFPO-DA and PFHpA can be analyzed under methods Table 3+ SOP and EPA Method 537 Mod.CASRN - Chemical Abstract Service Registry NumberEPA - Environmental Protection AgencyPFAS - Per- and Polyfluoroalkyl substances SOP - Standard Operating ProcedureTR0795APage 3 of 3February 2022
TABLE B.2
ADDITIONAL ANALYTES
Chemours Fayetteville Works, North Carolina
Geosyntec Consultants of NC, P.C.
Other Analytes Lab Method
Antimony 200.7 Rev. 4.4
Arsenic 200.7 Rev. 4.4
Barium 200.7 Rev. 4.4
Beryllium 200.7 Rev. 4.4
Cadmium 200.7 Rev. 4.4
Calcium 200.7 Rev. 4.4
Chromium 200.7 Rev. 4.4
Cobalt 200.7 Rev. 4.4
Copper 200.7 Rev. 4.4
Iron 200.7 Rev. 4.4
Lead 200.7 Rev. 4.4
Magnesium 200.7 Rev. 4.4
Manganese 200.7 Rev. 4.4
Molybdenum 200.7 Rev. 4.4
Nickel 200.7 Rev. 4.4
Potassium 200.7 Rev. 4.4
Selenium 200.7 Rev. 4.4
Silver 200.7 Rev. 4.4
Sodium 200.7 Rev. 4.4
Strontium 200.7 Rev. 4.4
Vanadium 200.7 Rev. 4.4
Zinc 200.7 Rev. 4.4
Chloride 300.0
Fluoride 300.0
Nitrate 300.0/353.2
Nitrite 300.0/353.2
Sulfate 300.0
1,4-Dioxane 522
Total Coliforms by Presence/Absence 9222B
Total Dissolved Solids SM 2540 C
Total Phosporus 200.7 Rev. 4.4
TR0795A Page 1 of 1 February 2022