NC0003425_Duke Energy LLHg Response Ltr_20240312

Duke Energy
DUKEEnvironmental Services
410 S.Wilmington Street
E N E RGY.
Raleigh, NC 27601
March 11, 2024
Vanessa Manuel, Assistant Regional Supervisor
Division of Water Resources
Raleigh Regional Office
3800 Barrett Drive
Raleigh, NC 27608
Subject: Information from contract lab on broken Low Level Mercury sample
bottles — December 2023 DMR
Roxboro Steam Electric Plant
NC0003425
Person County
Dear Ms. Manuel:
Attached to this letter please find information from Eurofins lab as to the events that led to the
missing weekly mercury sample in December 2023 and corrective actions implemented.
Duke Energy station personnel collected samples as required however, the low-level sample
vials were broken either in transit with the vendor courier or at our vendor lab facility. Upon
notification of this, Duke staff immediately notified your office, but were unable to collect another
sample for the week due to the delayed notification from the lab associated with the Christmas
Holiday. The attached document contains additional process improvements implemented by the
vendor lab to provide further assurance that additional occurrences are avoided.
Duke Energy requests that you consider these actions when evaluating any response to the
missing weekly sample. It is also our intent to request removal of this weekly sample
requirement when the renewal application is submitted later this year given the changes in
process flows that led to the requirement. If you have any additional questions, please feel free
to contact Mr. Steve Cahoon at [phone] or [e-mail].
Sincerely
Zach Hall
Vice President
Environmental, Health & Safety
Attachment
Cc: Tom Copolo
Steve Cahoon
Jason Robinson
Robert Howard
www.duke-ener-_r.corn

tiff eurofins
Environment Testing
03/11/2024
Jason Robinson
Duke Energy Corporation
13339 Hagers Ferry Road
Huntersville, NC 28078
Re: Broken Sample Vials Received for Low Level Mercury (LL HG)Analysis for Duke Energy-Additional
Corrective Action Information
Mr. Robinson,
In December of 2023, samples for LL Hg analysis were collected from Duke Energy to be submitted to our
Eurofins Pensacola facility for analysis. The timeline from courier sample pick-up to when Duke was
notified of the broken sample containers is summarized below:
Duke Energy LL Hg Timeline
Action Date
Charlotte Courier Pick-Up from Duke Energy 12/21/2023
Samples Shipped to Pensacola from Charlotte SC 12/21/2023
Samples Received in Pensacola 12/22/2023
Sample Login Review Completed 12/22/2023
PM Notified of Broken Containers by the Lab 12/27/2023 (After COB)
PM Notified Duke of Broken Containers 12/28/2023 (Morning)
As stated in the initial Corrective Action Response dated 12/29/23, our Charlotte Service Center has re-
assessed its cooler packing and shipping procedures to include extra layers of bubble wrap for sample
containers as well as inside of the cooler to eliminate shifting and movement during transit. LL Hg samples
will also be packaged in a separate cooler without thermal preservation to eliminate any unnecessary
objects packed inside of the cooler that may cause damage to the sample vials.
The Pensacola facility also incorporated process changes to aid in communicating issues of problematic
receipts in a more timely manner. Due to the stringent method requirements for LL Hg sample handling,
prior receipt procedures did not allow for full inspection of sample vials upon receipt in order to avoid
contamination when taken out of the bubble bags received in. Sample containers were received double
bagged from Duke with the client ID printed on the outside of the "dirty" bag.The double bagged samples
were then packed in single bubble wrap bags for shipping. Once received in Pensacola,the coolers would
be unpacked, but the LL Hg samples would not be removed from bubble bags-only opened just enough to
read the client labels then re-sealed with the LIMS generated client labels affixed to the outside of the
bubble bag. Client samples would not be fully removed from the "clean" interior bag for labeling and
complete inspection until they were transferred to the clean area for LL Hg analysis. Only then would
communication proceed regarding broken sample containers.
These procedures, while meticulous, disallowed the containers to be fully inspected upon receipt which
would delay communicating issues of broken containers in a timely manner to PMs and clients. As such, no
record of any issues upon lab receipt were documented or communicated for these samples.The sample
Eurofins Environment Testing Southeast, LLC 5102 LaRoche Avenue T 1 912-354-7858
Savannah,GA 31404-6019 www.EurofinsUS.com/Env

tiff eurofins
Environment Testing
receipt confirmation,which includes the receipt checklist, was emailed to Duke on 12/22/23 and listed no
discrepancies or issues with sample containers.This, in addition to the holidays, led to a 5-day delay in
notifying the PM about this occurrence. Furthermore, it is inconclusive as to when the containers broke
and the sample volume was lost- in transit, upon receipt, or upon transfer to the lab for analysis. It is likely
that the 3rd party courier mishandled this cooler shipment over the busy holiday season resulting in the
vials being damaged.
With the incorporation of changes in packing samples for shipment from Charlotte and adjusting receipt
procedures in Pensacola, samples will now be fully inspected upon receipt in the Pensacola Receiving
Department. Since samples are already submitted double bagged,the containers will be fully removed
from the bubble bag in the receiving department without risk of contamination. Once out of the bubble
bag, containers can be fully inspected for breakages with more timely notifications sent to PMs regarding
non-conformances and container issues.This will allow for more accurate real-time notifications of such
issues to the client.
Should you have any further questions regarding this occurrence or if additional information is necessary,
please feel free to contact me at [phone] or via email at [e-mail].
Sincerely,
U�
Polly Thornton
Quality Assurance Manager
Eurofins Environment Testing Southeast, Savannah
Eurofins Environment Testing Southeast, LLC 5102 LaRoche Avenue T 1 912-354-7858
Savannah,GA 31404-6019 www.EurofinsUS.com/Env

05/05/10 rev 2.0
Sample Login Acknowledgement
Job 400-248845-1
Client Job Description: J23110072 Roxboro NPDES Weekly Dewater(Week 3) Report To: Duke Energy Corporation
Purchase Order#: 10865759 Jason Robinson
Work Order#: J23110072 13339 Hagers Ferry Road
Project Manager: Todd Rea Huntersville,INC 28078
Job Due Date: 12/29/2023
Job TAT: 3 Days
Max Deliverable Level: II Bill To: Duke Energy Corporation
Accounts Payable
Earliest Deliverable Due: 12/29/2023 13339 Hagers Ferry Road
Huntersville,INC 28078
Login 400-248845
Sample Receipt: 12/22/2023 9:48:00 AM Number of Coolers: 1
Method of Delivery: FedEx Priority Overnight Cooler Temperature(s)(Co): 0.0;
Lab Sample# Client Sample ID Date Sampled Matrix
Method Method Description/Work Location Rpt Basis Dry/Wet**
400-248845-1 2023027182 12/20/2023 10:15:00 AM Water
1631E Mercury,Low Level/In-Lab Total Wet
400-248845-2 2023027183 12/20/2023 10:15:00 AM Water
1631E Mercury,Low Level/In-Lab Total Wet
400-248845-3 2023027184 12/20/2023 10:15:00 AM Water
1631E Mercury,Low Level/In-Lab Total Wet
400-248845-4 2023027185 12/19/2023 1:00:00 PM Water
1631E Mercury,Low Level/In-Lab Total Wet
400-248845-5 2023027186 12/20/2023 10:15:00 AM Water
1631E Mercury,Low Level/In-Lab Total Wet
Method on-hold
*Wet/Dry indicates whether the reported results will be corrected for moisture content, and based on sample Wet weight or Dry weight. Page 1 of 1

Login Sample Receipt Checklist
Client: Duke Energy Corporation Job Number:400-248845-1
Login Number:248845 List Source: Eurofins Pensacola
List Number: 1
Creator:Perez,Trina M
Question Answer Comment
Radioactivity wasn't checked or is</=background as measured by a survey N/A
meter.
The cooler's custody seal,if present, is intact. True
Sample custody seals, if present,are intact. N/A
The cooler or samples do not appear to have been compromised or True
tampered with.
Samples were received on ice. True
Cooler Temperature is acceptable. True
Cooler Temperature is recorded. True 0.0°C IR-8
COC is present. True
COC is filled out in ink and legible. True
COC is filled out with all pertinent information. True
Is the Field Sampler's name present on COC? True
There are no discrepancies between the containers received and the COC. True
Samples are received within Holding Time(excluding tests with immediate True
HTs)
Sample containers have legible labels. True
Containers are not broken or leaking. True
Sample collection date/times are provided. True
Appropriate sample containers are used. True
Sample bottles are completely filled. True
Sample Preservation Verified. N/A
There is sufficient vol.for all requested analyses,incl.any requested True
MS/MSDs
Containers requiring zero headspace have no headspace or bubble is N/A
<6mm(1/4").
Multiphasic samples are not present. True
Samples do not require splitting or compositing. True
Residual Chlorine Checked. N/A
Eurofins Pensacola

05/05/2010 rev 2.0
Sample Login Analytes / Limits
Job 400-248845-1
Client Job Description: J23110072 Roxboro NPDES Weekly Dewater(Week 3) Report To: Duke Energy Corporation
Purchase Order#: 10865759 Jason Robinson
Work Order#: J23110072 13339 Hagers Ferry Road
Project Manager: Todd Rea Huntersville,INC 28078
Job Due Date: 12/29/2023
Job TAT: 3 Days
Max Deliverable Level: II Bill To: Duke Energy Corporation
Accounts Payable
Earliest Deliverable Due: 12/29/2023 13339 Hagers Ferry Road
Huntersville,INC 28078
Login 400-248845
Sample Receipt: 12/22/2023 9:48:00 AM Number of Coolers: 1
Method of Delivery: FedEx Priority Overnight Cooler Temperature(s)(Co): 0.0;
Method Rpt Basis Units Sample#s Applicable
Method Description
1631E Total MDL RL 1,2,3,4,5
Mercury,Low Level
Mercury 0.2 0.5 ng/L
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