4101_Guilford_CityHighPoint_Riverdale_MSWLF_Seaboard_RemedialProgressReport_FID1819416_20231020

SEABOARD GROUP HAND THE CITY OF HIGH POINT
October 20, 2023
Eric B. Aufderhaar, P.G., Environmental Program Consultant
North Carolina Department of Environmental Quality
Division of Waste Management
1646 Mail Service Center
Raleigh, North Carolina 27699-1646
Re: Response to TM-12 PFAS Monitoring Workplan Approval with Conditions
Former Seaboard Chemical and Riverdale Drive Landfill Site
Jamestown, Guilford County, North Carolina
EPA ID No. NCD071574164/ Solid Waste Permit No. 4101-MSWLF-1979
Dear Mr. Aufderhaar:
In response to the PFAS Monitoring Workplan Approval with Conditions correspondence dated
September 18, 2023 from the NC DEQ, the former Seaboard Group/City of High Point (Parties)
agree to the conditions of approval as outlined below:
Sample Locations
In addition to the five monitoring wells and two surface water locations proposed in the Workplan,
the Parties agree to add monitoring wells W-4A and PW-3D to the sample locations for evaluation
of PFAS by EPA Draft Method 1633. These two additional wells will be sampled using low -flow
methodology and a HydraSleeve sampling device, respectively.
Confirmatory Sampling
As discussed during the August 2, 2023 on-line meeting between the Parties and NC DEQ, a
stepwise approach to sample collection was acceptable and future monitoring requirements for
PFAS would be determined based on the results of this initial monitoring event. The Site has been
monitored for several years, groundwater flow direction and transport pathways are documented
and understood. The need for "confirmation" sampling may not be appropriate and we suggest
further discussion with the NC DEQ consistent with our August 2nd discussion following a review
of the initial monitoring results for PFAS compounds.
Randleman Lake PFAS Data
The Parties have identified several existing sources of PFAS data for Randleman Lake. Surface
water samples have been collected upstream of the Site from City Lake used by the City of High
Point as a water supply. City Lake is approximately 5.25 miles upstream of the Site on the Deep
River which forms the headwaters of Randleman Lake. The City of High Point has collected
samples from this water source for PFAS analysis and the results are provided in the 2022 Annual
Drinking Water Quality Report. This report is available at this link:
htt2s:Hissuu.com/cityofbighpoint/docs/2022 water Quality

Response to TM-12 PFAS Monitoring Workplan Approval with Conditions
Former Seaboard Chemical and Riverdale Drive Landfill Site
Page 2
Surface water samples have also been collected downstream of the Site by the Piedmont Triad
Regional Water Authority (PTRWA). The PTRWA samples were collected from the intake to the
water system which is located approximately nine miles downstream of the Site. The analytical
results of the PFAS samples collected by PTRWA is provided in the 2022 Annual Drinking Water
Quality Report which is available at this link:
http://ptrwa.org_previewc3 8.carrierzone.com/2022%20PTRWA%20CCR.12df
The Parties are also aware of PFAS samples collected from Randleman Lake by the NC Division
of Water Resources (NCDWR). These samples were collected by the Intensive Survey Branch
and included Randleman Lake samples downstream of the Site. The results of the PFAS sampling
conducted by NCDWR will reportedly not be available until late February 2024. The NCDWR-
Intensive Survey Branch contact is Craig Hoover with the Intensive Survey Branch: (919)783-
8413 craig_.hoover(kncdenr.gov
Please contact us if there are any questions or comments regarding this correspondence.
Respectfully,
Seaboard Group II and City of High Point
Mr. Craig Coslett, Project Coordinator
de maximis, inc.
1550 Pond Road, Suite 120
Allentown, PA 18104
610-360-7539 Cell
CC: Jackie Drummond - NCDEQ Division of Solid Waste