The Chemours Company
Fayetteville Works
22828 NC Highway 87 W
Fayetteville, NC 28306

September 30, 2019

Sheila Holman
Assistant Secretary for the Environment
1601 Mail Service Center
Raleigh, NC 27699-1601
sheila.holman@ncdenr.gov
Kemp Burdette
Cape Fear River Watch
617 Surry Street
Wilmington, NC 28401(910) 762-5606
kemp@cfrw.us
Re:

Submission Pursuant to Consent Order Paragraph 12.eDear Ms. Holman and Mr. Burdette,
Chemours is pleased to submit the enclosed reports pursuant to paragraph 12.e of theConsent Order (CO) entered by the Superior Court for Bladen County on February 25, 2019. Thefollowing reports are being transmitted:•••

Old Outfall 002 Surface Water Sampling Results
Engineering Report Old Outfall 002 GAC Pilot Study Results
PlumeStop Phase 1 Pilot Study at Old Outfall 002

As required by paragraph 12.e of the CO, samples were required to be collected once permonth beginning in March 2019 with results reported by September 30, 2019. These results arereported in the attached Old Outfall 002 Surface Water Sampling Results report. The sampling
results show only minor variations from month to month for most constituents. Consistent withprevious sampling conducted at Old Outfall 002, Hexafluoropropylene oxide dimer acid (HFPODA) was detected at the highest concentration of constituents analyzed via method 537 andPerfluoro-2-methoxyacetic acid (PFMOAA) was the highest detected Table 3+ constituent.
Paragraph 12.e of the CO requires the completion of a pilot study “to determine its
control efficiency for all PFAS identified in Old Outfall 002. The results of this pilot testing shallbe supported by at least three (3) months of sampling data and submitted to DWR for review andapproval.” Accordingly, Chemours has completed bench and pilot scale testing of granular
activated carbon (GAC) to remove PFAS constituents from the water at Old Outfall 002. Thebench and pilot scale testing found F400 GAC demonstrated effective removal of the indicator
compounds PFMOAA and HFPO-DA along with other tracked and reported PFAS compounds.
The PlumeStop Pilot study was conducted to present a potential alternate technology toreduce mass flux to the Cape Fear River from the Old Outfall 002 Channel. Chemours
completed bench scale testing and a 3-month long pilot study to evaluate this technology. Theresults of the bench scale study and the pilot study indicate that PlumeStop can significantly
reduce the concentrations of HFPO-DA, PFMOAA, as well as many other PFAS compounds.
Over time, these reductions can translate to a reduction in the contaminant mass flux.
Based on the findings of the three studies presented above, Chemours continues torecommend capture of the Old Outfall 002 base flow (dry conditions) followed by treatmentusing GAC vessels in order to comply with the requirements of Paragraph 12 of the CO. While
PlumeStop was shown to be effective in remediating PFAS constituents, it is not able to meet theshort-term remedial objectives outlined in the CO for Old Outfall 002. We are also continuing
evaluation of other treatment technologies (e.g., ion exchange resins, other carbon-based media,
biological treatment), and an alternative treatment technology may be implemented (uponapproval by DEQ), either before or after installation of this proposed GAC treatment system.
***Please let us know if you need further information, or if you would like to discuss these
options further with us. We would appreciate receiving your approval soon, so that we may
timely proceed with implementation.
Sincerely,

Brian D. Long
Plant Manager
Chemours – Fayetteville Works

Enclosures
Old Outfall 002 Surface Water Sampling Results
Engineering Report Old Outfall 002 GAC Pilot Study Results
PlumeStop Phase 1 Pilot Study at Old Outfall 002

2

Cc:
William F. Lane, DEQ
Francisco Benzoni, NC DOJ
Michael Abraczinskas, DAQ
Michael Scott, DWM
Linda Culpepper, DWRDavid C. Shelton, Chemours
John F. Savarese, WLRK
Geoff Gisler, SELC3