NC0003417_Update to Pending Renewal App 2015_20150316

4as DUKE H.F.Lee Energy Complex
ENERGY® Duke Energy Progress
PROGRESS 1199 Black Jack Church Road
Goldsboro,NC 27530
March 11,2015
Mr. Jeff Poupart
North Carolina Division of Water Resources
1617 Mail Service Center
Raleigh, NC 27699-1617
Subject: Duke Energy Progress, Inc. RECEIVEDIDENR/DWR
H.F. Lee Energy Complex
Update to pending NPDES renewal application and MAR 16 2015
Submittal of chemical characterization of water
for dewatering ash basin and EPA Form 2C data
NC0003417 Water Quality
Permitting Section
Wayne County
Dear Mr. Poupart:
In response to the request from the North Carolina Division of Water Resources,please find attached
a chemical characterization of the ash basin free water, ash basin interstitial water and water from the sites
small chemical metal cleaning basin located adjacent to the ash basin is provided. The analysis conducted
and reported herein is consistent with the information requested by NC DENR for other Duke Energy
sites. This is submitted in support of potential upcoming dewatering activities that would be directed to
outfall 001.
The results of analysis on the chemical characterization of the ash basin free water, ash basin interstitial
water and small triangular basin water are presented: 1.)without additional treatment beyond the
treatment in the basin and 2.)after additional treatment using three different filter sizes.
Because of the low water levels in these basins,Duke foresees dewatering activities involving the use of
pumps and/or removal of sections of risers or stop logs to facilitate potential dewatering activities.
Specific dewatering work plans will be developed to assure the work will be done safely and in
compliance with all applicable requirements. These plans can be made available to you for review upon
request.
The following definitions may be useful as you consider these activities.
Ash basin free water: Water in an ash basin located above the settled layer of ash. Ash basin
free water has undergone treatment in the ash basin,has the same general characteristics as water
discharged when the facility was active sluicing ash to the ash basin, is largely devoid of Total
Suspended Solids and meets all applicable NPDES permit limits.
Ash basin interstitial water: Water in an ash basin that is located within the pore space of
accumulated wastewater sludge or slurry. Ash basin interstitial water must be removed from an
ash basin by some means such as trenching,well points, etc. and would likely require additional
treatment before being released to the environment.

Mr. Jeff Poupart
Update to HF Lee NPDES application
March 11, 2015
Page 2 of 3 RECEIVED/DENRIDWR
MAR 1 6 2015
Water Quality
The process we envision for dewatering the ash basins is as follows: Permitting Section
Ash basin free water will be removed from the primary basin via the use of pumps. Additional
treatment of ash basin free water may be completed via chemical and/or physical processes prior
to discharge through the secondary basin to Outfall 001. This treatment system may require the
addition of a coagulant and/or flocculent to enhance solids removal. Interstitial water removal
will be accomplished through rim ditching,trenching, and pumping. Additional treatment of ash
basin interstitial water may be completed via chemical and/or physical processes prior to
discharge through the secondary basin to Outfall 001. This treatment system may require the
addition of a coagulant and/or flocculent to enhance solids removal. Compliance monitoring
required by the NPDES Permit as well as robust process control monitoring will be performed.
Process control monitoring and additional safeguards and controls to be employed include:
All pumps will be controlled to stop at a user-defined level set point which is set manually every
7 days. The maximum free water drawdown rate will be one foot over seven days. Following
free water removal, accumulated storm-water will be removed at a maximum rate of 2 feet over
1 day. Additionally, dewatering discharge rates will not exceed historical discharge rates of 2.01
MGD as reported in the NPDES renewal request submitted in November of 2012 .
The ash basin pumps will be controlled with a real-time process control total suspended solids
(TSS)meter. A real-time process control pH meter will control a carbon dioxide injection system
to maintain pH between 6.0 and 9.0 standard units(SU).
In addition to the real-time monitoring,handheld TSS and pH meters will be used daily for
additional process control field measurements of samples. The handheld TSS meter will undergo
laboratory validation and site-specific field verification. Daily pH monitoring will be conducted
with a portable pH meter. Discharge flow rates will be monitored daily using an inline flow
meter, a handheld flow meter, or a v-notch discharge weir. Normal monitoring required by the
NPDES permit will continue uninterrupted during the dewatering process.
As the dewatering process transitions from the removal of ash basin free water to the removal of
ash basin interstitial water phase it is anticipated that a filtration system may be used to maintain
compliance with permit limits. Please include a provision in the modified permit to allow the
use of a coagulant or flocculent from the state's approved list to facilitate the filtration process if
needed.

Mr. Jeff Poupart
Update to HF Lee NPDES application
March 11, 2015
Page 3 of 3
If you have any questions,please contact Mr. Shannon Langley at(919)546-2439.
I certify, under penalty of law, that this document and all attachments were prepared under my direction
or supervision in accordance with a system designed to assure that qualified personnel properly gather
and evaluate the information submitted. Based on my inquiry of the person or persons who manage the
system, or those persons directly responsible for gathering the information, the information submitted is,
to the best of my knowledge and belief true, accurate, and complete. I am aware that there are
significant penalties for submitting false information, including the possibility of fines and imprisonment
for knowing violations.
Sincerely,
td utt
Rick Grant-Plant Manager
H.F. Lee Energy Complex
Enclosures
RG/esl
cc: Ricky Miller w/enclosure
Shannon Langley w/enclosure-NCRH14