NC0003468_Correspondence_20220523

Strickland, Bev
From: Kebede, Adugna
Sent: Tuesday, May 10, 2022 12:57 PM
To: Chernikov, Sergei
Cc: Behm, Pamela
Subject: RE: Dan River Model
Hi Sergei,
I have looked at the Dan River. The previous model used for other projects is the CORMIX model (Rogers Energy,
Mooresboro) and the Dan River model is the Environmental Fluid Dynamics Code (EFDC).
Overall, based only on the report I do not have any major issue. It appears they have done a reasonable job in using
measured data (depth and velocity) for model calibration and using the 7Q10 model scenario (critical conditions) to
verify whether the thermal mixing zone meets the discharge permit requirements. The only concern I have is their
recommendation to remove the upstream/ downstream monitoring requirement because of the uncertainty associated
with application of complex models such as EFDC. Continuing to have upstream/ downstream monitoring for a few years
to verify and confirm the model results and evaluating whether the discharge permit requirements are met is a sensible
option. Please let me know if you have any question.
Thanks.
Adugna
From: Behm, Pamela
Sent: Tuesday, April 5, 2022 12:59 PM
To: Kebede, Adugna <[e-mail]>
Subject: FW: Dan River Model
Adugna,
See request from Sergei, can you take a look? We can see if there are immediate concerns, but given this is not a model
we have run or evaluated, not sure what NPDES will do. We can't start taking on CORMIX too.
From: Chernikov, Sergei <[e-mail]>
Sent: Wednesday, March 30, 2022 9:53 AM
To: Behm, Pamela <[e-mail]>
Cc: Dowden, Doug <[e-mail]>
Subject: Dan River Model
Pam,
Could you please review the attached thermal model and let me know if you have any questions or concerns. The
document is only about 22 pages long with many illustrations.
Unfortunately, we lost our only modeler recently and don't have anybody with modeling expertise to review this model.
i

Thank you!
Sergei
Sergei Chernikov, Ph.D.
Environmental Engineer III
Industrial NPDES Permitting Unit
NEW Tel. [phone]
1617 Mail Service Center, Raleigh, NC 27699-1617
Express Mail: 512 N. Salisbury St., Raleigh, NC 27604
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