NC0039586_Comments_20180515

'DUKE 410 S.Wilmington Street
Raleigh,NC 27601
ENERGY® P.O.Box 1551:
NCRHQ15
Raleigh,NC 27602
0 919 546.6146
0:984.209 0940
f:919.546.3669
May 15, 2018
Ms. Cindy Moore, Supervisor
Aquatic Toxicology Unit
NC DEQ Division of Water Resources
1621 Mail Service Center
Raleigh,NC 27699-1621 REC99VEDIDENRIDWR
Subject: Duke Energy Progress,LLC MAY 1.8 Z018
Shearon Harris Nuclear Power Plant (HNP)
NPDES Permit No. NC0039586 Water Res
ources
ection
Part I (A)(9)—Schedule of Compliance (Outfall 006) Permitting
Wake County -
Dear Ms. Moore,
On August 29,2016,NC DEQ DWR issued NPDES Permit NC0039586 with an effective date of
September 1, 2016. Contained within this permit were new effluent requirements for Copper and
Zinc for Outfall 006 (Combined Outfall for Internal Outfalls 001-005) serving HNP.
Subsequently,Duke Energy Progress,LLC (Duke Energy) submitted a Corrective Action Plan
(CAP) and an implementation plan for a Water Effects Ratio (WER) on September 1, 2017 and
February 28, 2018, respectively. We received comments from your office via an email to Mr.
Bob Wilson, HNP Site Environmental Professional, dated April 16, 2018. This email was a
follow-up to a telephone discussion with Mr.Wilson on March 28, 2018 concerning the Water
Effects Ratio (WER) plan HNP submitted. This letter provides a response to the comments
provided by your office.
1. Comment: A suggestion to model your discharge in order to define the dilution factor or
instream waste concentration (IWC). The dilution factor that is being used is 90% which
is the highest we use and would need to be used in the WER study. Potentially, a reduced
dilution factor could be more appropriate and thus reduce the IWC or dilution factor used
in the NPDES permit for establishing limits.
Response: The HNP NPDES permit limits for metals for(copper and zinc) are based on
100% effluent (no dilution); therefore, we plan to perform the WER studies assuming this
will not change. While we understand that 90% is the maximum dilution factor
achievable in whole effluent toxicity(WET)tests, this will not affect the results of the
WER since effluent toxicity assays are compared against assays in laboratory water with
the same metals concentrations. If HNP is not able to demonstrate compliance after the
WER is conducted, use of a mixing zone analysis, as outlined in Chapter 5 of EPA's
Water Quality Standards Handbook(EPA, 1994b) may be pursued during Year 3 or 4 of
the compliance schedule,if necessary, as stated in the CAP.
1

`Mr.Cindy Moore,Supervisor
NC DEQ DWR Aquatic Toxicology Unit
Page 2
2. Comment: All chemical and WET testing will need to be done by NC certified labs.
Response: ETT Environmental Inc. (NC Toxicity Certification#022) will be used for
WET testing for the WER studies. They have previously conducted WER studies for
metals based on the U.S. EPA Guidance [Interim Guidance on Determination and Use of
Water-Effect Ratios for Metals—1994] for discharges in South Carolina. Supporting
analytical work will also be done by NC certified laboratories.
The three rounds of WER studies are expected to be completed during May, July, and September
2018. This time frame was chosen to cover the period of the year with the highest cooling
demand and thus the most impact from HNP. This schedule is tentative and is subject to change.
We hope this letter and response to your comments are satisfactory. If any clarifications are
needed,please provide such to us within thirty(30) days so we can ensure we adapt our WER
studies accordingly.
If you have any questions regarding this matter or wish to discuss in further detail,please do not
hesitate to contact Mr. Bob Wilson,HNP Site Environmental Professional, at(919) 362-2444 or
myself at [phone].
Sincerely,
lfra
Donald L. Saf ' ,
Senior Technical Spec isior
Carolinas Permitting and Compliance
cc: Mr. Bob Wilson, HNP Site Environmental Professional
Mr. Danny Smith, NC DEQ DWR Raleigh Regional Office
Ms. Julie Grzyb,NC DEQ DWR NPDES Permitting Unit
Ms. Connie Brower,NC DEQ DWR Classifications, Standards &Rules Review
Mr. Bill Kreutzberger, CH2M