NCG030246_Tier Letter_20191211

Moore, James
From: Moore, James
Sent: Wednesday, December 11, 2019 1:18 PM
To: Street, Steve L.; Khan, Zahid
Subject: RE: [External] Stormwater Discharge Benchmark Exceedance Certificate of Coverage No.
NCG030246
Steve we are in receipt of your letter dated December 10, 2019 regarding benchmark exceedances. Since you are
operating under the new NCG030000 permit issued November 2018 you are required to monitor monthly until 3
consecutive sample results are below the benchmark values or until monitoring relief is granted. Please email over a
spreadsheet summarizing monitoring data for the last 2 years. Also, in Q1 next year I should be available for a technical
assistance inspection if requested.
James Moore
Assistant Regional Engineer
Land Quality Division
Division of Energy, Mineral, and Land Resources
North Carolina Department of Environmental Quality
Phone: [phone] x2138
Fax: [phone]
Email: [e-mail]
Mailing Address: 610 E. Center Ave. Suite 301
Mooresville, NC 28115
othing • ,.
Email correspondence to and from this address is subject to the
North Carolina Public Records Law and may be disclosed to third parties
From: Street, Steve L.[mailto:[e-mail]]
Sent: Tuesday, December 10, 2019 3:55 PM
To: Khan, Zahid <zahid. [e-mail]>
Cc: Moore, James <[e-mail]>
Subject: [External] Stormwater Discharge Benchmark Exceedance Certificate of Coverage No. NCG030246
Dear Mr. Khan,
The Corning Optical Communications — Hickory Manufacturing and Technology Center (HMTC), located at 1164 23rd
Street SE, Hickory, NC, currently operates under General Permit No. NCG030000 with respect to its stormwater
discharges, as evidenced by Certificate of Coverage No. NCG030246. Analytical results from Outfall # 3 have exceeded
the benchmark values for copper and zinc, and analytical results from Outfall # 5 have exceeded the benchmark value

for copper, such that the facility is subject to Tier Three requirements under Part II, Section B of General Permit No.
NCG030000.
HMTC is in the process of conducting further investigation to identify potential sources of these compounds and to
develop methods to reduce their concentration in stormwater discharge. HMTC previously installed filters on drain inlets
leading to Outfall # 3 to reduce the total suspended solids content, which resulted in a reduction in the metals
concentration of subsequent monitoring events, although not below the benchmark values. A new filter was recently
installed that is designed to remove both solids and metals, which has resulted in a further reduction of zinc and copper
levels. The facility will continue to monitor both stormwater outfalls on a monthly basis, as required under Tier Two
monitoring, and will further evaluate what additional controls may be necessary.
Attached is the letter containing this information signed by the site's Plant Manager. A hard copy of the letter is also
being mailed to your office.
Regards,
Steve Street
Sr. EHS Coordinator
Hickory Manufacturing and Technology Center
(o) 828-901-6695
(c) 828-244-3921

CORNING
December 10, 2019
Ahmed Koilakh Hickory Manufacturing and t 828-901-5699
Plant Manager Technology Center f 828-901-5665
1164 A 231d St SE [e-mail]
Hickory. NC 28602 www.corning.com
Mr. Zahid Khan
Regional Engineer, Mooresville Regional Office
Division of Energy, Mineral, and Land Resources
610 East Center Avenue, Suite 301
Mooresville, NC 28115
RE: Stormwater Discharge Benchmark Exceedance
Certificate of Coverage No. NCG030246
Dear Mr. Khan:
DEC 1 1 2019
DENR-DEMLR
Land Quality Section
Mooresville Regional Office
The Corning Optical Communications — Hickory Manufacturing and Technology Center
(HMTC), located at 1164 23rd Street SE, Hickory, NC, currently operates under General
Permit No. NCG030000 with respect to its stormwater discharges, as evidenced by Certificate
of Coverage No. NCG030246. Analytical results from Outfall # 3 have exceeded the
benchmark values for copper and zinc, and analytical results from Outfall # 5 have exceeded
the benchmark value for copper, such that the facility is subject to Tier Three requirements
under Part 11, Section B of General Permit No. NCG030000.
HMTC is in the process of conducting further investigation to identify potential sources of
these compounds and to develop methods to reduce their concentration in stormwater
discharge. HMTC previously installed filters on drain inlets leading to Outfall 4 3 to reduce
the total suspended solids content, which resulted in a reduction in the metals concentration of
subsequent monitoring events, although not below the benchmark values. A new filter was
recently installed that is designed to remove both solids and metals, which has resulted in a
further reduction of zinc and copper levels. The facility will continue to monitor both
stormwater outfalls on a monthly basis, as required under Tier Two monitoring, and will
further evaluate what additional controls may be necessary.
Please contact me if you have any questions at 828-901-5699.
Sincerely,
1 -
Ahmed Koilakh
Plant Manager
cc: Kim Kelley
Steve Street
0 2019 Coming incorporated. All Rights Reserved.