DEQ-CFW_00001214

Question # I from Cave Fear River Watch
My first question is about the discharge of C-8 into the ground water that was
reported to the State in 2005. It is my understanding that this discharge was investigated
by DuPont and that the results of this investigation were reviewed by both NCDENR and
the EPA.
What are the results of this. investigation? Was the source of the discharge
determined? If so, has that been remediated and are there safeguards in place to assure
that future discharges can be quickly identified, reported and corrected?
Response to Question # I
The DuPont facility in Fayetteville, NC began manufacturing ammonium
perfluorooctanoate (APFO), which is also known as C-8, in 2002. Prior to this date, the
plant neither produced C-8 compounds nor used these compounds in its manufacturing
processes.
Initial groundwater samples were collected in 2002, and confirmation
groundwater samples were collected in early 2003. APFO was detected in the parts -per -
trillion range in these samples. In June 2003, DuPont -Fayetteville reported the detections
of APFO in groundwater to NCDENR as the discovery of a new chemical in the
groundwater. Also in 2003, the E.I. 0�duPont.QoWpany submitted a Letter of Intent
(LOI) to EPA. In this LOI, DuPont proposed to investigate all its facilities that manage
or have managed C-8 compounds.
DuPont -Fayetteville has installed and sampled 39 temporary and permanent
monitoring wells on -site. Analytical results greater than North Carolina's 2 ppb IMAC
for APFO in groundwater have been reported for three of the wells. These wells are
located near the plant's APFO manufacturing unit.
The facility has also sampled nine off -site groundwater supply wells. The
analytical results for eight of these wells were reported as non -detections. Two
groundwater samples were collected at the ninth well. One sample was non -quantifiable
for APFO while APFO was reported at a concentration of 0.011 ppb in the second
sample.
In response to a request by NCDENR, EPA Region 4 observed a sampling event
conducted by DuPont -Fayetteville and split groundwater, surface water, and sediment
samples with the facility. The EPA splits were analyzed by EPA's National Enforcement
Investigations Center and National Exposure Research Laboratory. The analytical results
were reported in 2006. EPA's analytical results were consistent with those reported by
the facility.
Analytical data suggest the sources for APFO in groundwater at the DuPont -
Fayetteville facility are two surface impoundments and the APFO manufacturing unit.
DEQ-CFW 00001214

44,
Regarding the question of sediment carryover from the outfall channel, the
- Division has approved a request to relocate the final effluent discharge
y ' outfall. This relocation was done to stop the erosion (and discharge of
sediment) a�s oFcurring in the existing effluent channel. After
reviev k1112661% report that showed that the proposed relocation would
not affect dissolved oxygen levels in the Cape Fear River, approval was
granted to relocate the outfall above Lock and Dam #3. This approval was
given on February 26, 2008.
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