NCS000546_Tier response notification_20230321

Young, Brianna A
From: Glenn, Elizabeth <[e-mail]>
Sent: Tuesday, March 21, 2023 12:49 PM
To: Khan, Zahid
Cc: Georgoulias, Bethany; Young, Brianna A
Subject: [External] Allen Steam Station NCS000546 - Tier 1 Notification
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Mr. Khan —
As directed by Part D., Section D-5 of the subject permit (NCS000546), notification is required to the Mooresville Regional
Office of outfalls entering Tier 1 status.
Results were received on 3/7/2023 for the sampling event for Stormwater on 2/17/2023. Tier One status for Total
Suspended Solids, Mercury, Selenium, and Copper were triggered by a sample result noted in the table below.
Parameter
Benchmark
SW010
SWO18
TSS
100 mg/L
180 mg/L
140 mg/L
Cu
10 ug/L
20.5 ug/L
Se
Hg
5 ug/L
8.85 ug/L
14.5 ug/L
12 ug/L
A stormwater management inspection was conducted on 3/16/23.
Construction activities on site and truck traffic on nearby haul roads appear to be contributing factors. A cleanup of
roadside ditches and refreshing of rock checks was performed on 3/27/23.
Please let me know if you have any questions.
Thank you,
J. Elizabeth Glenn
Permitting & Compliance
Duke Energy, Environmental Services
Office: [phone]
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