NC0024392_Correspondence_20230414 (2)

ROY COOPER
Govemor
ELIZABETH S. BISER
Secretary
RICHARD E. ROGERS, JR.
Director
March 17th, 2023
Edward Pigott
McGuire Nuclear Station
12700 Hagers Ferry Road
Huntersville, NC 28078
NORTH CAROLINA
Environmental Quality
Subject: Review of Duke Energy's McGuire Nuclear Station: Lake Norman
Maintenance Monitoring Program: 2021 (NC0024392).
Dear Mr. Pigott:
Thank you for your submission of the aforementioned document. Based on a review of
the data provided to us, we find it is consistent with our 2017 and 2022 data. The year
2021 was a wetter year than in the past and small changes in some of the parameters
reflect this. While Lake Norman was determined to be mesotrophic based on Duke
Energy's use of the Carlson Trophic Index in 2021, our data using the NCTSI scoring
system indicated that the reservoir in 2022 was primarily oligotrophic. Again, this may
reflect the differences in precipitation in 2021 versus 2022. Values for chlorophyll a,
nutrients, water temperature and pH were similar between Duke Energy's 2021 report
and our monitoring data for 2022. The trophic status of Lake Norman continues to
remain stable and no significant changes over time are apparent from the two thermal
discharges into the reservoir.
If you have any questions regarding these comments, please do not hesitate to contact
me.
Sincerely,
qfis Johnson
, Water Sciences Section
Cc: Andrew Pitner, Acting Environmental Regional Supervisor (Mooresville Regional Office)
Sergei Chernikov, Complex Permitting Unit
North Carolina Department ofEnvironmentat Quality I Division of Water Resources
® 512 North Salisbury Street 1 1611 Mait Service Center I Raleigh, North Carolina 27699-1611
.a.919.707.9000
�Mcei q 4Ye¢Lv.4d Oi>Ri