NC0088838_Permit Exceedance Response_20191022

OCT 2 1) 11019
a division of Radiator Specialty Company
October 22, 2019
Mr. Edward Watson
Hydrogeologist
North Carolina Department of Environmental Quality
Water Quality Regional Operations Section
Division of Water Resources
610 East Center Avenue
Mooresville, North Carolina 28115
Corrective Action - Permit Exceedance — July 2019
Radiator Specialty Company
Indian Trail, Union County, North Carolina
Permit No. NCO088838
Dear Mr. Watson:
Radiator Specialty Company (RSC) respectfully submits for your review, this
written submission of a status update to a noncompliance that occurred in July 2019 to
National Pollutant Discharge Elimination System (NPDES) Permit No. NC0088838.
On July 25, 2019, RSC received the analytical results associated with the July 16,
2019 quarterly sample collected from Outfall 001. The results indicate the presence of
tetrachloroethene at a concentration of 6.7 micrograms per liter (µg/L) and 1-4,dioxane at
a concentration of 230 µg/L. These concentrations exceed the Permit limits of 3.3 µg/L
for tetrachloroethene and 80 µg/L for 1,4-dioxane, respectively.
Based on preliminary information provided by the analyzing laboratory on July 23,
2019, RSC shut the groundwater recovery system down. Following discontinuing the
discharge, RSC sampled the equalization tank and each individual recovery well for the
subject parameters. Based on the results of these samples, RSC proposes to perform the
following corrective actions.
® Recirculate the collected groundwater in the equalization tank through the air
stripping tower to reduce the concentration of the contained water to below the
permitted limit for tetrachloroethene.
® RSC will replace flowmeters on two recovery wells. New calibrated flowmeters
will assist RSC in manually operating the four (4) recovery wells.
600 Radiator Road — Indian Trail, NC 28079-5225 — Telephone: [phone] — Fax: [phone] — www.rscbrands.com

Mr. Edward Watson
October 22, 2019
Page 2
® RSC will restart the groundwater recovery system after all modifications are made
to the system. RSC will resample the effluent for the subject parameters upon
restart of the system.
Radiator Specialty Company appreciates the North Carolina Department of
Environmental Quality's cooperation and assistance
ssi e call n his ma er. i 15ou have any
questions or require additional information, please
Sincerely,
Radiator Specialty Company
A0.
Stuart A. Kerkhoff, CHMM
Operator in Responsible Charge
NPDES\STATUSUPDATE 1019. DOC