DEQp00020147

Linda,
I was out at Chemours on Friday 11/3/2017to find out what happened on 10/6/2017 that caused a spike
in the C3 Dimer Acid sample resultt that wereawith
nconceike Johnson,
rn after phocess sampling on9/18/2017.ristel Compton, and Kevin Dunham. I
inspected several areas of the plan
now sent
a tank
The first area we visited was then aSodium
fra k tankeThe frack tank is This
isflow
thensoff loadedaond sent oo tpor
aadjustment, and then captured
incineration. The picture below shows this process.
The next area we visited was the IXM pmer site. The lXM polymer wastewater is now catured in t is off loaded and sent out for incineration. Allphe frack the
temporary frack tank. Once this tank is full,
tanks have secondary containment. The picture below shows this process.

The third area we visited was the Vinyl Ethers South Stack. This is the area that the spill occurred.
Chemours thinks the spill occurred due to the decontamination process of blowing out the Dimer Acid
Fluoride line for vapor space. This caused the Dimer Acid to vent to the scrubber causing the Acid to
foam. The foam was then vented out of the South Stack. Due to not having enough vapor space in the
acid line and the differential pressure being raised and lowered manually for the decontamination
process, Dimer Acid was vented to the scrubber. This happened during the Company shutdown when
some lines where being manually activated and deactivated to decontaminate the scrubber.
To prevent this from happening in the future, there will be a system in place to verify the liquid full line
has been purged. The old system was to purge for 10 minutes, which may not have been enough. There
will be training with the operators to limit flows or stop the flow altogether if they see swings in the
differential pressure. The pictures below show the scrubber and stack. The Dimer Acid came out of the
top of the stack like an aerosol and landed on the ground around the water channel that discharges
from Outfall 002. Rains following the discharge on 10/7, 10/8, and 10/9 also washed the leftover
residual into the stream.
To the left is the Vinyl Ethers South Scrubber and to the right is the Stack the Dimer Acid discharged
from.

The stream you see to the right is beside the stack that had the discharge. This stream discharges to
Discharge 002.
The forth area we visited was the DEG Tank area. Waste water from this area is now captured, and sent
out for incineration. The sump adjacent to this tank (Products Sump) has been cleaned out. The picture
below shows this area.