NC0003417_Fact Sheet_20221012

DEPARTMENT OF ENVIRONMENTAL QUALITY
DIVISION OF WATER RESOURCES
FACT SHEET
NPDES No. NC0003417
Facility Information
Applicant/Facility
Duke Energy Progress, LLC / H.F. Lee Energy Complex
Applicant Address:
1199 Black Jack Church Road, Goldsboro, NC 27530
Facility Address:
1199 Black Jack Church Road, Goldsboro, NC 27530
Permitted Flow (MGD):
Outfall 001 - 2.16 MGD
Type of Waste:
Industrial & domestic
Facility Classification:
Physical -Chemical Grade 1
Permit Status:
Major Modification
County:
Wayne
Miscellaneous
Receiving Stream:
Neuse River
State Grid:
F26NE
Stream Classification:
WS-IV; NSW
USGS Quad:
NW Goldsboro
Drainage Area (mi2):
2,050
303(d) Listed?
No, TMDL is in
effect for TN
Summer 7Q10 (cfs)
263
Sub-basin/HUC:
030412/03050105
Winter 7Q10 (cfs):
260
Regional Office:
Washington
30Q2 (cfs)
375
Permit Writer:
Sergei Chernikov
Average Flow (cfs):
1,100
Date:
IWC (%):
Outfall 001 - 1.3%
SIC/NAICS code
4911 / 2211
SUMMARY
This is a Major Modification of the Duke Energy permit for the H. F. Lee Energy Complex in
Wayne County. The permit is being modified to make the following changes:
1) Include 21 minor seeps adjacent to the cooling pond in the list of the permitted
discharges.
2) Add updated compliance boundary map approved by the NCDWR on 2/23/2022.
The areas of seepage associated with the ash basin and cooling pond are currently covered and
regulated by a Consent Order EMC SOC WQ S18-006 between North Carolina Environmental
Management Commission and Duke Energy. Upon completion of the SOC, regulatory oversight
of seeps associated with the ash basin will be transferred to the groundwater corrective action
plan (CAP).
The groundwater CAP does not address the areas of seepage associated with the cooling pond.
The cooling pond will continue to support the Combined Cycle Facility past the closure of the
SOC. The cooling pond did not receive wastewater streams from any coal ash wastewater
processes.
There are 21 seeps identified around the cooling pond's 4.63 miles perimeter dike. The seeps
might be submerged or exposed to the air depending on the water level in the Neuse River.

NPDES PERMIT FACT SHEET H.F. Lee Energy Complex
NPDES No. NC0003417
Seeps have intermittent flow, which complicates sampling. During the 2021 sampling event
only 6 of the 21 seeps exhibited sufficient flow to obtain a sample for analysis. The combined
flow from 6 seeps was measured at less than 0.034 MGD. This flow represents only a very
minor fraction of the flow from the ash pond (<0.02%) and has no measurable impact on the
receiving stream.
Impact from the seeps on the receiving stream is monitored by instream sampling upstream and
downstream of the facility. Review of the data for 2019, 2020, and 2021 indicates that all
monitored parameters are either below detection level or well below the standard. The data also
shows that downstream concentration is not significantly different from the upstream
concentration for all measured parameters. The monitored parameters are the following: total
arsenic, total selenium, total mercury (method 1631E), total chromium, dissolved lead,
dissolved cadmium, dissolved copper, dissolved zinc, bromide, total hardness, and total
dissolved solids (TDS).
All the remaining terms and conditions of the permit remain unchanged.
The Lee Combined Cycle Plant consists of 3 combined cycle combustion turbines brought
online in 2012. Also, located on the site is the Wayne County Combustion Turbine Plant/Site
which consists of 5 simple cycle combustion turbines, four of them brought online in 2000 and
the fifth in 2009. Altogether, the five simple cycle combustion turbines and the three combined
cycle combustion turbines generate a total electric capacity of over 1800 Megawatts. All units
are capable of firing oil and natural gas.
Previously, the H.F. Lee Energy Complex had three coal-fired units and four oil -fueled
combustion turbine units. These were retired in September and October of 2012. The coal-fired
generating units and the four oil -fueled combustion turbines have been demolished and the
coal pile was recently removed. The decanting of the ash pond water has been completed.
The H.F. Lee Combined Cycle Power Plant has more than twice the capacity of the retired coal
plant with significant emissions reductions of carbon dioxide, sulfur dioxides, nitrogen oxides,
and mercury.
TN BACKGROUND:
While in operation, the coal-fired Steam Electric Plant installed a Rotamix selective catalytic
reduction (SCR) system in 2007, in response to air pollution control requirements. This incurred
a total nitrogen discharge, and the facility joined the Neuse River Compliance Association
(NRCA). The Rotamix selective catalytic reduction (SCR) system used to remove a majority of
nitrogen oxides in the Steam Electric Plant was retired in 2012. Even though the facility is
currently classified as "non -nutrient bearing", Duke Energy remains a member of the NRCA
and its nitrogen discharge is governed by the Compliance Association's permit NCC000001.
RECEIVING WATERS:
Receiving water is the Neuse River. The Neuse River is a class WS-IV; NSW waterbody in the
Neuse River Basin. The facility outfalls are located approximately 8-10 miles upstream of
Goldsboro's potable water supply intake.
Page 2 of 18

NPDES PERMIT FACT SHEET H.F. Lee Energy Complex
NPDES No. NC0003417
TECHNOLOGY BASED EFFLUENT GUIDELINES:
H.F. Lee is subject to EPA effluent guideline limits per 40 CFR 423 - Steam Electric Power
Generating Point Source Category as amended November 3, 2015. The facility is also subject to
the Cooling Water Intake Structures Rules (40 CFR 125) effective October 14, 2014 and to the
North Carolina Senate Bill 729 - Coal Ash Management Act (CAMA).
OUTFALL DESCRIPTIONS:
Discharges to Outfall 001 Active Ash basin
No process wastewater flows are being sent to the active ash basin. The active ash basin is actually
not active but is named that on all the maps in the application and sometimes referred to as the
1982 ash basin. Fly ash and bottom ash wastewaters were sent to this basin when the plant used
coal-fired units. Ash transport wastewaters and additional wash waters from the precipitator and
air pre -heater that were typically sent to the ash basin have all ceased. Wastewaters from the Filter
Plant (water treatment), the Wayne County Combustion Turbine Site, low volume wastes, and
other miscellaneous wastes that were once directed to the ash basin have all been redirected to
Outfall 002 since 2012.
Duke Energy wants to maintain Outfall 001 for decanting the ash basin which would later be
followed by dewatering. Within the next year or two after permit issuance, Duke Energy expects
to start groundwater remediation on the eastern side of the ash basin. Extracted groundwater
would be treated in the same wastewater treatment system (WTS) as the decant/ dewatering
wastewaters and discharged through Outfall 001.
No other wastewaters are to be discharged through Outfall 001 to the Neuse River except those
treated in the WTS.
Background on previous IWC used for Outfall 001: The historical average flow of the Ash Pond
wastewaters discharged to Outfall 001 is 2.5 MGD. Outfall 001 did not have a flow limit, and
flows varied. The permit issued in 2010 used an Instream Wastewater Concentration (IWC) of
2.1%, which was determined using a discharge flow of 3.58 MGD. This flow value was the 95'th
percentile of the maximum daily effluent flow data collected between 2006 and September 2008.
In 2010, the Whole Effluent Toxicity Testing concentration was changed to 2.1% from 1.41% used
in the 2004 permit.
Ash Basin Seeps
The facility identified 9 seeps (all non -engineered). All nine seeps are located around the active
ash basin. Seeps will be addressed through Special Order by consent EMC SOC WQ S18-006.
Discharges to Outfall 002 Cooling Pond
The facility uses an existing 545 acre closed -cycle cooling pond with baffled dikes to treat
recirculating condenser cooling and process water. Approximately 369 MGD of condenser
cooling water is re -circulated in the pond each day. Eleven MGD are lost to evaporation and
seepage. The applications states that 3-5 MGD are lost to natural evaporation during times the
units are in full operation. Up to 12.7 MGD can be withdrawn from the Neuse as make-up water.
Until recently, the Cooling Pond has not had a direct discharge to the Neuse since 1998 and a
discharge is only expected during an extremely heavy rainfall event or a hurricane.
Page 3 of 18

NPDES PERMIT FACT SHEET H.F. Lee Energy Complex
NPDES No. NC0003417
Hurricane Matthew hit North Carolina starting on Oct. 8, 2016 and the Neuse River rose above
the berm surrounding the H.F. Lee cooling pond. In an article published by the Charlotte
Observer on Oct. 12, 2016, USGS said, the Neuse near Goldsboro peaked at 29.7 feet, breaking the
record of 28.8 feet set after Hurricane Floyd in 1999. As the Neuse receded, a 50-foot crack
developed in the berm surrounding the cooling pond which holds 1.2 billion gallons. Wastewater
flowing through the cracked berm discharged to the Neuse River, there has been no estimate on
the total volume discharged at this point.
Rain from Hurricane Florence (September 2018) again caused the Neuse River to rise and enter
the cooling pond. The cooling pond discharged through the spillway (Outfall 002) during this
storm event.
In addition to the recirculating condenser cooling and process water, other wastewaters sent to
the cooling pond include: cooling tower blowdown from the Wet Surface Air Cooler and the
combined cycle Heat Recovery Steam Generator (HRSG), Wayne County Combustion Turbine
Site wastewaters which pass through a sump lift station, reverse osmosis reject wastewaters from
the water treatment plant, and Lee Combined Cycle Plant Site wastewaters which are initially
treated with an oil/water separator. Sanitary wastewaters are no longer discharged to the cooling
pond. Storm water from containment areas and miscellaneous wastewaters as described in the
updated permit renewal application submitted on August 31, 2016 are discharged to the cooling
pond, as well. On occasion wastewaters from the clarifier in the water treatment plant are sent to
the cooling pond. Coal pile runoff, which has ceased, and low volume wastewaters regulated
under 40 CFR 423, are discharged to the cooling pond.
Cooling Pond Seeps
The facility identified 15 unpermitted seeps (all non -engineered). All 15 seeps are located around
the cooling pond. Seeps will be addressed through Special Order by Consent EMC SOC WQ S18-
006.
Discharges to Outfall 002 Cooling Pond.
Outfall 003 was permitted in 2010 in order to prepare for the retirement of the 3 coal-fired units
in 2012 and the construction of the natural gas -fired combined cycle generation facility.
However, in early 2013 the discharge to Outfall 003 was discontinued after one month due to
operational concerns with total suspended solids. Wastewaters were re-routed to the cooling
pond from Outfall 003 to accommodate modifications needed to be made to the outfall
structure. These modifications were to be conducted after the permit from the US Army Corps
of Engineers was secured. Currently no wastewaters are being sent to Outfall 003 which
discharges to the Neuse River and Outfall is being eliminated from the permit.
The following waste streams currently discharge to the Cooling Pond (Outfall 002: cooling
tower blowdown from the Wet Surface Air Cooler and the combined cycle Heat Recovery
Steam Generator (HRSG), Wayne County Combustion Turbine Site wastewaters which pass
through a sump lift station, reverse osmosis reject wastewaters from the water treatment plant,
Lee Combined Cycle Plant Site wastewaters which are initially treated with an oil/water
separator, low volume wastewaters, and equipment and containment drain wastewaters.
Page 4of18

NPDES PERMIT FACT SHEET H.F. Lee Energy Complex
NPDES No. NC0003417
Outfall 002A - additional outfall in cooling pond
The heavy rains from Hurricane Matthew (October 2016) caused the Neuse River to rise high
enough to enter the cooling pond at H.F. Lee through Outfall 002 and by over topping the
cooling pond dike. As a result of the severe weather conditions, the dike of the cooling pond
breached in the southeast corner of the pond. As a result, the new emergency outfall was added
at the site of the breach. The addition of the new emergency outfall allows the facility to avoid a
scenario where the pond breaches because of the influx of water from the river. The new
Outfall, identified as Outfall 002A in the permit, would only be used in the event of severe
weather or required maintenance.
Rain from Hurricane Florence (September 2018) again caused the Neuse River to rise and enter
the cooling pond. The cooling pond discharged through the spillway during this storm event.
The new emergency outfall was not used.
COMPLIANCE REVIEW/PROPOSED ACTIONS
Outfall 001- Active Ash Basin
This outfall is subject to the Effluent Limitations Guidelines (ELG) in Table 1.
Table 1. ELG Outfall 001 (BPT Low volume waste sources)
Pollutant
a
Daily Maximum
(DM)
Monthly Average
(MA) +
ELG
TSS
100 mg/L
30 mg/L
40 CFR 423.12 (b) (3) and (4)
Oil & Grease
20 mg/L
15 mg/L
40 CFR 423.12 (b) (3) and (4)
pH
6 to 9 SU
40 CFR 423.12 (b) (1)
PCB's
No discharge of PCB's
40 CFR 423.12 (b) (2)
The facility normally incinerates chemical metal cleaning waste and stated no such wastes have
been sent to the 1982 ash basin for disposal.
These Effluent Guidelines are in effect in the current permit and will be maintained for Outfall
001 in the renewal. In 2016, Duke Energy started to decant some wastewaters from the active
ash basin but after 3 months, decanting ceased. Upon permit renewal, Duke Energy is planning
to begin the Ash Pond decommissioning which will start with decanting followed by
dewatering of the active ash basin.
Phase 1. Ash Basin Decanting/Normal Operations at Outfall 001:
To begin decommissioning, bulk and interstitial ash basin water will be decanted from the active
ash pond through Outfall 001. If necessary to meet water quality standards, wastewater treatment
will be brought onsite to assist in the process. All decant wastewaters would pass through the
Wastewater Treatment System (WTS) prior to being discharged through Outfall 001. The WTS
will be designed to handle a minimum flow of 500 gpm and a maximum flow of 1500 gpm (2.16
MGD). As stated in the permit renewal, the level of water in the ash pond should not be lowered
more than 1 ft/day during the decanting phase.
• DMR review:
Except for the decanting of the active ash basin for 3 months in 2016, there has been no discharge
from Outfall 001 since October 2012. The historical average flow from Outfall 001 is 2.5 MGD.
DMR data from 2016, 2C data submitted with the November 2012 renewal application, and data
Page 5 of 18

NPDES PERMIT FACT SHEET
H.F. Lee Energy Complex
NPDES No. NC0003417
from samples of free water located above the settled layer of ash taken on Feb. 15, 2015, were all
reviewed. There were no violations of permit limits.
Table 2. 2016 DMR Summary Outfall 001 - Ash Basin Decanting
Parameter
Average
Maximum
Minimum
Flow (MGD)
0.52
0.81
0.026
TSS (mg/L)
<5
7.6
< 5
O&G (mg/L)
<5
<5
<5
Nitrite plus Nitrate
(mg/L)
0.012
0.02
0.01
Arsenic (µg/L)
12.9
18.4
5.95
Selenium (µg/L)
10.7
15.4
10.7
Total Nitrogen (mg/L)
0.25
0.35
0.17
Total Phosphorus (mg/L)
0.012
0.015
0.01
pH (S.U.)
7.8
8.7
7.1
Passed 2 of 2 toxicity tests during three months of decant discharge.
• RPA Outfall 001- Ash Basin Decanting:
The need for toxicant limits is based upon a demonstration of reasonable potential to exceed
water quality standards, a statistical evaluation that is conducted during every permit renewal
utilizing the most recent effluent data for each outfall. The Reasonable Potential Analysis (RPA)
is conducted in accordance with 40 CFR 122.44 (d) (i). The NC RPA procedure utilizes the
following: 1) 95% Confidence Level/95% Probability; 2) assumption of zero background; 3) use
of 1/2 detection limit for "less than" values; and 4) stream flows used for dilution consideration
based on 15A NCAC 2B.0206. Effective April 6, 2016, NC began implementation of dissolved
metals criteria in the RPA process in accordance with guidance titled NPDES Implementation of
Instream Dissolved Metals Standards, dated June 10, 2016. This guidance is attached to the fact
sheet.
A reasonable potential analysis was performed for arsenic, antimony, barium, cadmium,
chlorides, chromium, copper, fluoride, lead, mercury, molybdenum, nickel, selenium, sulfate,
thallium, and zinc. A reasonable potential analysis was conducted using the maximum effluent
value reported from one of the following sources: 2016 DMR data, Nov. 2012 2C application
form, and the Ash basin free water samples submitted to DWR on March 11, 2015. Pollutants of
concern for the decant wastewater included toxicants with positive detections and associated
water quality standards/criteria. The maximum wastewater treatment plant design flow of 2.16
MGD was used in the RPA along with historical 7Q10 and average flow statistics for the Neuse
River. Upstream drainage statistics from the Neuse River near Clayton, provided by USGS on
May 15, 2009, supported the use of the historical values.
Based on this analysis, the following permitting actions are proposed for this permit:
o Effluent Limit with Monitoring. The following parameters will receive a water quality -
based effluent limit (WQBEL) since they demonstrated a reasonable potential to exceed
applicable water quality standards/criteria: None.
o Monitoring Only. The following parameters will receive a monitor -only requirement
since they did not demonstrate reasonable potential to exceed applicable water quality
Page 6 of 18

NPDES PERMIT FACT SHEET H.F. Lee Energy Complex
NPDES No. NC0003417
standards/criteria, but the maximum predicted concentration was >50% of the
allowable concentration: total selenium.
o No Limit or Monitoring: The following parameters will not receive a limit or monitoring,
since they did not demonstrate reasonable potential to exceed applicable water quality
standards/criteria and the maximum predicted concentration was <50% of the
allowable concentration: antimony, barium, cadmium, chlorides, chromium, copper,
fluoride, lead, molybdenum, nickel, sulfate, thallium, and zinc. Mercury and arsenic did
not demonstrate reasonable potential to exceed applicable water quality
standards/criteria and the maximum predicted concentration was <50% of the
allowable concentration; however, they continue to be pollutants of concern and
monitoring for these parameters was maintained in Outfall 001 as discussed below.
o Summary of new limits added based on RPA: none.
o Summary of existing limits deleted based on RPA: none.
• Toxicity Testing:
Current Requirement: Outfall 001 - Chronic P/F @ 2.1% using Ceriodaphnia, Quarterly
Recommended Requirement: Outfall 001- Chronic P/F @ 1.3% using Ceriodaphnia, Monthly
The new Instream Waste Concentration (IWC) of 1.257%, rounded to 1.3 %, is based on the
maximum design flow of 2.16 MGD for the Wastewater Treatment System and the historical
summer 7Q10 flow of 263 cfs.
• Mercury Evaluation:
Four samples were provided on mercury as follows:
November 2012 2C application 2C data - < 200 ng/L
March 2015 active ash basin free water samples: <0.5 ng/ L,1.35 ng/L, <0.5 ng/L
Annual average discharge limitations for mercury at Outfall 001 are based on a Technology Based
Effluent Limitation (TBEL) of 47 ng/L and a Water Quality Based Effluent Limitation (WQBEL)
of 955 ng/L. The TBEL was established in the 2012 NPDES Mercury TMDL Implementation
Strategy and the WQBEL is based on the Water Quality Standard of 12 ng/L divided by the IWC.
Data shows Duke Energy can comply with the TBEL during Ash Basin decanting, however,
mercury monitoring will be added to the permit since it is a pollutant of concern. No limits are
required for mercury.
Table 3. Monitoring Requirements/Proposed Changes Outfall 001- Ash Basin Decanting
Parameter
Existing
Effluent Limit/
Monitoring
requirements
Changes
it :
Basis
Flow
Monitor
2.16 MGD DM
15A NCAC 2B.0505
TSS
30 mg/L MA
100 mg/ L DM
No changes
40 CFR 423.12(b) (3) and (4)
Oil & Grease
15 mg/L MA
20 mg/ L DM
No changes
40 CFR 423.12(b)(3) and (4)
Total Selenium
and Total Arsenic
Monitor
quarterly
Weekly
monitoring
Pollutant of concern for ash.
Selenium based on RPA.
Page 7 of 18

NPDES PERMIT FACT SHEET
H.F. Lee Energy Complex
NPDES No. NC0003417
Total Mercury
No requirement
Weekly
Monitoring
Pollutant of concern for ash.
Total Hardness
No requirement
Monthly
Monitoring
Collect data for RPA
Turbidity
No requirement
Monthly
Monitoring
Required by EPA per letter dated Feb.
25, 2009.
Total Nitrogen
Total Phosphorus
Weekly
Monitoring
Monthly
Monitoring
15A NCAC 2B .0500, Neuse Nutrient
Management Strategy, NRCA
membership
Nitrate/nitrite as N
Weekly
Monitoring
Monthly
Monitoring
Pollutant of Concern for WS waters
pH
6 to 9 SU
No changes
State WQ standards, 15A NCAC 2B
.0200 and 40 CFR 423.12 (b) (1)
Chronic Toxicity
See condition A. (11.)
15A NCAC 2B.0500
Phase II. Ash Basin Dewatering and Groundwater Remediation at Outfall 001:
Secondly, to meet the requirements of the Coal Ash Management Act of 2014, the facility will
dewater the ash pond by removing the interstitial water in the ash and then excavate the ash to
deposit it in approved landfills. After decanting is completed and when water in the ash settling
basin is lowered to within three feet of the ash deposits, the Permittee will begin dewatering. As
with decanting, wastewater treatment will be provided if needed. Ash Basin dewatering flows,
as well as storm water from the WTS pad area, may be treated at the WTS prior to being
discharged through Outfall 001. The facility's discharge rate from the dewatering process is
estimated to be 500 gpm to 1500 gpm (2.16 MGD).
Within the first two years after permit issuance, Duke Energy will design an extraction well
system to treat contaminated groundwater on the eastern side of the active ash basin. The
groundwater will be extracted, pumped to a sump, and treated in the same WTS as the bulk and
interstitial ash basin water. The wastewaters will discharge through Outfall 001 to the Neuse
River.
The facility submitted data for the standing surface water in the active ash pond, interstitial water
in the ash, and interstitial ash water that was treated by filters of various sizes. The facility's
estimated discharge rate for the groundwater extraction is 0.9-1.8 MGD. Groundwater
monitoring data from wells on the eastern and southeastern side of the active ash basin were
reviewed. To introduce a margin of safety the highest measured concentration of a parameter
from the active ash basin or the groundwater wells was used in the reasonable potential analysis.
The maximum Wastewater Treatment System design flow of 2.16 MGD was used as the
permitted flow.
• RPA Outfall 001- Ash Basin Dewatering:
A reasonable potential analysis was performed for arsenic, antimony, barium, cadmium,
chlorides, chromium, cobalt, copper, fluoride, lead, mercury, molybdenum, nickel, selenium,
sulfate, thallium, total dissolved solids and zinc
Based on this analysis, the following permitting actions are proposed for the dewatering phase:
Page 8of18

NPDES PERMIT FACT SHEET H.F. Lee Energy Complex
NPDES No. NC0003417
o Effluent Limit with Monitoring. The following parameters will receive a water quality -
based effluent limit (WQBEL) since they demonstrated a reasonable potential to exceed
applicable water quality standards/criteria: arsenic.
o Monitoring Only. The following parameters will receive a monitor -only requirement
since they did not demonstrate reasonable potential to exceed applicable water quality
standards/criteria, but the maximum predicted concentration was >50% of the
allowable concentration: none
o No Limit or Monitoring: The following parameters will not receive a limit or monitoring,
since they did not demonstrate reasonable potential to exceed applicable water quality
standards/criteria and the maximum predicted concentration was <50% of the allowable
concentration: antimony, barium, cadmium, chlorides, chromium, cobalt, copper,
fluoride, lead, molybdenum, nickel, sulfate, thallium, and zinc. Mercury and selenium did
not demonstrate reasonable potential to exceed applicable water quality
standards/criteria and the maximum predicted concentration was <50% of the allowable
concentration; however, they continue to be pollutants of concern and monitoring for
these parameters was maintained in Outfall 001.
Monitoring requirements for Outfall 001 - Ash Pond Dewatering and Groundwater Extraction
are the same as Table 3 for most parameters. Arsenic limitations have been added and sampling
frequencies were increased to weekly for all parameters except nutrients and toxicity.
Phase III. Groundwater Remediation:
Thirdly, after completing the decanting and dewatering of the ash basin groundwater
remediation may still be occurring. The groundwater remediation wastewaters will be treated in
the WTS prior to being discharged through Outfall 001.
Groundwater extraction will continue at an estimated rate of 0.9-1.8 MGD. To introduce a margin
of safety the highest measured concentration of a parameter from the groundwater monitoring
wells was used in the reasonable potential analysis.
• RPA Outfall 001- Groundwater Remediation:
A reasonable potential analysis was performed for arsenic, cadmium, copper, nickel, selenium,
nitrates, thallium, and zinc.
Based on this analysis, the following permitting actions are proposed for the dewatering phase:
o Effluent Limit with Monitoring. The following parameters will receive a water quality -
based effluent limit (WQBEL) since they demonstrated a reasonable potential to exceed
applicable water quality standards/criteria: none
o Monitoring Only. The following parameters will receive a monitor -only requirement
since they did not demonstrate reasonable potential to exceed applicable water quality
standards/criteria, but the maximum predicted concentration was >50% of the
allowable concentration: none.
o No Limit or Monitoring: The following parameters will not receive a limit or monitoring,
since they did not demonstrate reasonable potential to exceed applicable water quality
standards/criteria and the maximum predicted concentration was <50% of the
allowable concentration: monitoring will be required for parameters of concern even
though the maximum predicted was not > 50% (arsenic, cadmium, copper, lead,
mercury, barium, and selenium).
Page 9 of 18

NPDES PERMIT FACT SHEET
H.F. Lee Energy Complex
NPDES No. NC0003417
Effluent Limits & Monitoring requirements for Outfall 001 - Groundwater Extraction are listed
below in Table 4.
Table 4. Effluent Limits & Monitoring Requirements - Proposed discharge to Outfall 001 -
Groundwater Remediation:
Parameter
Effluent Limits
Monitoring
requirements
Basis
Flow
1.8 MGD
Weekly
15A NCAC 2B.0505 and gw
treatment max design
Total arsenic
No limit
Monthly
Monitoring
Pollutant of concern for ash.
Total selenium
No limit
Monthly
monitoring
Pollutant of concern for ash.
Total mercury
No limit
Monthly
monitoring
Pollutant of concern for ash.
Total cadmium
No limit
Monthly
monitoring
Pollutant of concern for ash.
Total copper
No limit
Monthly
monitoring
Pollutant of concern for ash.
Total lead
No limit
Monthly
monitoring
Pollutant of concern for ash.
Total barium
No limit
Monthly
monitoring
Pollutant of concern for ash.
Total Hardness
No limit
Monthly
monitoring
Collect data for RPA
Turbidity
No limit
Monthly
monitoring
Required by EPA letter
dated Feb. 25, 2009
Total Nitrogen
Total
Phosphorus
No limits
Monthly
monitoring
15A NCAC 2B .0500, Neuse
Nutrient Management
Strategy, NRCA
membership
Nitrate/nitrite
as N
No limit
Monthly
monitoring
Pollutant of Concern for
WS waters
pH
6 to 9 SU
2/Month
State WQ standards, 15A
NCAC 2B .0200 and 40 CFR
423.12 (b) (1)
Chronic Toxicity
See condition A. (11.)
15A NCAC 2B.0500
Outfall 002 and 002A Cooling Pond
These outfalls are subject to the Effluent Limitations Guidelines (ELG) in Table 5.
Table 5. ELG Outfall 001 (BPT/BAT for Low volume waste sources, cooling tower blowdown,
and coal pile runoff apply)
Pollutant
Daily
Maximum
Monthly
Average
ELG
(DM)
(MA)
Page 10 of 18

NPDES PERMIT FACT SHEET
H.F. Lee Energy Complex
NPDES No. NC0003417
TSS
50 mg/L
30 mg/L
40 CFR 423.12 (b) (3) and (9)
Oil & Grease
20 mg/L
15 mg/L
40 CFR 423.12 (b) (3)
pH
6 to 9 SU
40 CFR 423.12 (b) (1)
PCB's
No discharge of PCB's
40 CFR 423.12 (b) (2)
Free available chlorine
0.5 mg/L
0.2 mg/L
40 CFR 423.13 (d) (1)
126 priority pollutants
No detectable amount
(engineering. calc. allowed)
40 CFR 423.13 (d) (1)
Total Chromium
0.2 mg/L
0.2 mg/L
40 CFR 423.13 (d) (1)
Total Zinc
1.0 mg/L
1.0 mg/L
40 CFR 423.13 (d) (1)
Add footnotes for free chlorine, TRC, and 126 priority pollutants
40 CFR 423.13 (d) (1)
The facility normally incinerates chemical metal cleaning waste and stated no such wastes have
been sent to the Cooling Pond for disposal.
There has been no discharge from Outfall 002 since 1998. In October of 2016 heavy rain from
Hurricane Matthew caused river water to over -top the cooling pond dike and enter the pond
through Outfall 002 structure. The cooing pond breached in the southeast corner and Duke
Energy is proposing to add a new emergency outfall at the site of the breach. The new Outfall,
identified as Outfall 002A in the permit, will only be used in the event of severe weather or
required maintenance.
• DMR review:
Results of a process control sample from the sites cooling pond taken in close proximity to Outfall
002 was submitted with an updated 2C form on March 11, 2015. To introduce a margin of safety
the maximum reported concentration of a parameter from the 2C application was used in the
reasonable potential analysis. There were no violations of permit limits for Outfall 002 during the
last five years.
• RPA Outfall 002- Cooling Pond:
A reasonable potential analysis was performed for arsenic, antimony, barium, cadmium,
chromium, copper, fluoride, lead, mercury, molybdenum, nickel, selenium, sulfate, thallium,
and zinc.
Based on this analysis, the following permitting actions are proposed for the cooling pond:
o Effluent Limit with Monitoring. The following parameters will receive a water quality -
based effluent limit (WQBEL) since they demonstrated a reasonable potential to exceed
applicable water quality standards/criteria: total molybdenum
o Monitoring Only. The following parameters will receive a monitor -only requirement
since they did not demonstrate reasonable potential to exceed applicable water quality
standards/criteria, but the maximum predicted concentration was >50% of the
allowable concentration: none
o No Limit or Monitoring: The following parameters will not receive a limit or monitoring,
since they did not demonstrate reasonable potential to exceed applicable water quality
standards/criteria and the maximum predicted concentration was <50% of the
allowable concentration: antimony, barium, cadmium, chromium, copper, fluoride, lead,
nickel, sulfate, thallium, and zinc. Mercury and arsenic did not demonstrate reasonable
potential to exceed applicable water quality standards/criteria and the maximum
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NPDES PERMIT FACT SHEET H.F. Lee Energy Complex
NPDES No. NC0003417
predicted concentration was <50% of the allowable concentration; however, they
continue to be pollutants of concern and monitoring for these parameters was included
in Outfall 002 and 002A.
Effluent Limitations and Monitoring requirements for Outfall 002 - Cooling Pond are listed below
in Table 6.
• Toxicity Testing:
Current Requirement: Outfall 002 - Acute Episodic Toxicity using Fathead Minnow, 24 hr
static test, first five discrete discharge events than annually
Recommended Requirement: Outfall 002 - Acute Episodic Toxicity using Fathead Minnow, 24
hr static test, first five discrete discharge events than annually
In addition to a review of the 2C data for Outfall 002, discharge data from cooling pond seeps
was evaluated to assess if other parameters should be monitored at Outfall 002. A review of the
cooling pond seep data showed significant levels of arsenic, lead, mercury and fluoride.
However, antimony, cadmium, and selenium were tested at levels below detection for all
cooling pond seeps. Based on the RPA evaluation of the cooling pond seep data and the limited
effluent data for Outfall 002, monitoring for arsenic, lead, mercury and fluoride were added to
Outfall 002.
Table 6. Monitoring Requirements/ Proposed Changes Outfall 002 - Cooling Pond
Parameter
Existing Effluent
limits/Monitoring
requirements
Changes
Basis
Flow
Monitor each
event
No changes
15A NCAC 2B.0505
TSS
30 mg/L MA
100 mg/L DM
Daily maximum
for TSS changed
to 50 mg/L
MA - 40 CFR 423.12(b) (4)
DM - 40 CFR 423 (b) (9) coal pile runoff
was discharged to the cooling pond
until recently.
Oil & Grease
15 mg/L MA
20 mg/ L DM
No changes
40 CFR 423.12(b)(4)
Temperature
32.0 °C
No changes
State WQ standards, 15A NCAC 2B
.0200
Total chromium
No requirement
Added limits and
monitoring
0.2 mg/ L MA
0.2 mg/ L DM
40 CFR 423.13 (d)(1)
Total zinc
No requirement
Added limits and
monitoring
1.0 mg/ L MA
1.0 mg/ L DM
40 CFR 423.13 (d)(1)
Total iron
Monitor
Eliminate
State standard removed
monitoring
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NPDES PERMIT FACT SHEET
H.F. Lee Energy Complex
NPDES No. NC0003417
Total
molybdenum
No requirement
Added limits and
monitoring
13,734 µg/L MA
13,734 µg/L DM
Reasonable potential to exceed water
quality criteria.
Total arsenic
Monitor
No changes
Pollutant of concern for ash and cooling
pond seep discharge
Total lead,
mercury, and
fluoride.
No requirement
Added event
monitoring
Pollutants of concern for ash and
cooling pond seep discharge
Total Hardness
No requirement
Added event
monitoring
Collect data for RPA
Total Residual
Chlorine
No requirement
Added limit and
monitoring
28.0 µg/L DM
State WQ standards, 15A NCAC 2B
.0200
Free Chlorine
No requirement
Added limits and
monitoring
0.2 mg/ L MA
0.5 mg/ L DM
40 CFR 423.13 (d) (1) and footnotes 40
CFR 423.13 (d) (2) and (3)
pH
6 to 9 SU
No changes
State WQ standards, 15A NCAC 2B
.0200
Acute Toxicity
See condition A. (12.)
15A NCAC 2B.0500
Outfall 002A was given the same Effluent Limitations and Monitoring Requirements as Outfall
002. Duke Energy submitted three analytical test analysis (full effluent pollutant scans) from the
discharge at the cooling pond breach in October 2016. The analysis reported most parameters as
non -detectable and detected samples were all less than water quality standards/criteria.
• RPA Outfall 005a and Outfall 005b - Inactive Ash Basins Dewatering:
The need for toxicant limits is based upon a demonstration of reasonable potential to exceed
water quality standards, a statistical evaluation that is conducted during every permit renewal
utilizing the most recent effluent data for each outfall. The Reasonable Potential Analysis (RPA)
is conducted in accordance with 40 CFR 122.44 (d) (i). The NC RPA procedure utilizes the
following: 1) 95% Confidence Level/95% Probability; 2) assumption of zero background; 3) use
of 1/2 detection limit for "less than" values; and 4) stream flows used for dilution consideration
based on 15A NCAC 2B.0206. Effective April 6, 2016, NC began implementation of dissolved
metals criteria in the RPA process in accordance with guidance titled NPDES Implementation of
Instream Dissolved Metals Standards, dated June 10, 2016. This guidance is attached to the fact
sheet.
A reasonable potential analysis was performed for arsenic, antimony, cadmium, chromium,
copper, lead, mercury, nickel, selenium, thallium, and zinc. A reasonable potential analysis was
conducted using the maximum effluent value reported from the Major Modification
Application. The maximum wastewater pump capacity of 8.0 MGD was used in the RPA along
with historical 7Q10 and average flow statistics for the Neuse River. Upstream drainage
statistics from the Neuse River near Clayton, provided by USGS on May 15, 2009, supported the
use of the historical values.
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NPDES PERMIT FACT SHEET H.F. Lee Energy Complex
NPDES No. NC0003417
Based on this analysis, the following permitting actions are proposed for this permit:
o Effluent Limit with Monitoring. The following parameters will receive a water quality -
based effluent limit (WQBEL) since they demonstrated a reasonable potential to exceed
applicable water quality standards/criteria: Mercury, the TBEL of 47.0 ng/L was
applied in accordance with the Statewide Mercury TMDL implementation strategy; and
Total Selenium.
o Monitoring Only. The following parameters will receive a monitor -only requirement
since they did not demonstrate reasonable potential to exceed applicable water quality
standards/criteria, but the maximum predicted concentration was >50% of the
allowable concentration: Total arsenic (monitoring for both parameters is recommended
based on the state procedure for coal-fired power plants), Total Antimony, and Total
Thallium.
o No Limit or Monitoring: The following parameters will not receive a limit or monitoring,
since they did not demonstrate reasonable potential to exceed applicable water quality
standards/criteria and the maximum predicted concentration was <50% of the
allowable concentration: Total Cadmium, Total Chromium, Total Copper, Total Lead,
Total Nickel, and Total Zinc.
• Toxicity Testing:
Recommended Requirement: Outfall 005a and Outfall 005b Chronic P/F @ 4.5% using
Ceriodaphnia, Monthly.
The new Instream Waste Concentration (IWC) of 4.5% is based on the maximum pump capacity
of 8.0 MGD and the historical summer 7Q10 flow of 263 cfs.
Table 7. Monitoring Requirements Outfalls 005a and 005b Inactive Ash Basins Dewatering
Paramete
Existing Effluent
Limit/ Monitoring
re . uirements
Flow
8.0 MGD DM for both
outfalls
15A NCAC 2B.0505
TSS
30 mg/L MA
100 mg/ L DM
40 CFR 423.12(b) (3) and (4)
Oil & Grease
15 mg/L MA
20 mg/ L DM
40 CFR 423.12(b)(3) and (4)
Total Selenium
111.0 µg/L MA
1,019.0 µg/L DM
Based on RPA
Total Antimony
Monthly Monitoring
Based on RPA
Total Thallium
Monthly Monitoring
Based on RPA
Total Arsenic
Weekly monitoring
Pollutant of concern for ash.
Total Mercury
TBEL of 47.0 ng/L and
Weekly Monitoring
Based on RPA and Mercury TMDL
implementation strategy
Total Hardness
Weekly Monitoring
Collect data for RPA
Turbidity
Weekly Monitoring
Required by EPA per letter dated Feb. 25, 2009.
Total Nitrogen
Total Phosphorus
Monthly Monitoring
15A NCAC 2B .0500, Neuse Nutrient
Management Strategy, NRCA membership
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NPDES PERMIT FACT SHEET
H.F. Lee Energy Complex
NPDES No. NC0003417
Nitrate/nitrite as N
Monthly Monitoring
Pollutant of Concern for WS waters
pH
6 to 9 SU
State WQ standards, 15A NCAC 2B .0200 and 40
CFR 423.12 (b) (1)
Chronic Toxicity
Monthly Monitoring
15A NCAC 2B.0500
Seep outfalls from the Active Ash Basin:
The Division identified 9 non -engineered discharges from 19 seeps located around the ash
settling basins. Seeps will be addressed through Special Order by consent EMC SOC WQ S18-
006.
Outfall 004- Beneficiation Plant
A new outfall for the discharge of the ash beneficiation facility is being added to the permit. The
facility will install a coal ash beneficiation system for ash reuse. The excavated ash will be re -
burned to remove carbon to make the material usable for reuse as a product in cement. Ponded
ash will be taken out of the ash basin and placed in an enclosed load -out area before its used in
the beneficiation unit. Wastewaters generated include truck wash water, waste water for dust
suppression and stormwater that comes in contact with the ash. Wastewaters will be collected
in a holding basin and treated in an oil/water separator. Flow is expected to be less than 0.005
MGD. Duke Energy is requesting the option to discharge to the Neuse River or to the cooling
pond.
To provide a wastewater characterization Duke Energy submitted data from a similar facility in
operation at another site. These data were used to complete an RPA.
A reasonable potential analysis was performed for arsenic, antimony, barium, cadmium,
chromium, copper, chlorides, TDS, lead, mercury, nickel, selenium, sulfate, thallium, and zinc.
Based on this analysis, the following permitting actions are proposed for Outfall 003:
o Effluent Limit with Monitoring. The following parameters will receive a water quality -
based effluent limit (WQBEL) since they demonstrated a reasonable potential to exceed
applicable water quality standards/criteria: Mercury.
o Monitoring Only. The following parameters will receive a monitor -only requirement
since they did not demonstrate reasonable potential to exceed applicable water quality
standards/criteria, but the maximum predicted concentration was >50% of the
allowable concentration: none.
o No Limit or Monitoring: The following parameters will not receive a limit or monitoring,
since they did not demonstrate reasonable potential to exceed applicable water quality
standards/criteria and the maximum predicted concentration was <50% of the
allowable concentration: arsenic, antimony, barium, cadmium, chromium, copper,
chlorides, TDS, lead, mercury, nickel, selenium, sulfate, thallium, and zinc did not
demonstrate reasonable potential to exceed applicable water quality standards/criteria
and the maximum predicted concentration was <50% of the allowable concentration;
however, they continue to be pollutants of concern and monitoring for these parameters
was included in Outfall 004 for reasons discussed in Table 9., below.
Table 8. Monitoring Requirements Proposed Beneficiation Plant
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NPDES PERMIT FACT SHEET
H.F. Lee Energy Complex
NPDES No. NC0003417
Parameter
Limits/Monitoring
requirements
Basis
Flow
Monitor
15A NCAC 2B.0505
pH
6 to 9 S.U.
State WQ standards, 15A NCAC 2B .0200
and 40 CFR 423.12(b)(1)
TSS
30 mg/L MA
100 mg/L DM
40 CFR 423.12(b) (3)
Oil & Grease
15 mg/L MA
20 mg/L DM
40 CFR 423.12(b)(3)
Total Dissolved Solids, Total
hardness, chlorides, sulfates,
arsenic, selenium, copper, lead,
nickel, thallium, and zinc.
Monitor
Parameters of concern
Total Mercury
47 ng/L annual
average limit
Mercury was detected at 47 ng/L in the
effluent to the beneficiation plant used as
wastewater characterization.
Acute Toxicity
Monthly
Monitoring
15A NCAC 2B .0500
COOLING POND SEEPS
• RPA for Seeps:
The need for toxicant limits is based upon a demonstration of reasonable potential to exceed
water quality standards, a statistical evaluation that is conducted during every permit renewal
utilizing the most recent effluent data for each outfall. The Reasonable Potential Analysis (RPA)
is conducted in accordance with 40 CFR 122.44 (d) (i). The NC RPA procedure utilizes the
following: 1) 95% Confidence Level/95% Probability; 2) assumption of zero background; 3) use
of 1/2 detection limit for "less than" values; and 4) stream flows used for dilution consideration
based on 15A NCAC 2B.0206. Effective April 6, 2016, NC began implementation of dissolved
metals criteria in the RPA process in accordance with guidance titled NPDES Implementation of
Instream Dissolved Metals Standards, dated June 10, 2016. This guidance is attached to the fact
sheet.
The RPA was also conducted for the combined flow from all the seeps. The concentration data
for each constituent was extracted from the Major Modification Application and used for the
RPA. The RPA was not considered for the parameters that don't have an applicable state water
quality standard or EPA criteria. Calculations included: As, Cd, Chlorides, Cr, Cu, F, Pb, Hg, Ni,
Se, Zn, Ba, B, Nitrate, and Sulfate. The combined flow volume for all the seeps was measured at
0.034 MGD. However, the flow of 0.34 MGD was used for the RPA to incorporate a safety
factor, account for potential new seeps that might emerge in the future or increase in flow
volume at the existing seeps.
The flow of 0.34 MGD was used in the RPA along with historical 7Q10 and average flow
statistics for the Neuse River. Upstream drainage statistics from the Neuse River near Clayton,
provided by USGS on May 15, 2009, supported the use of the historical values.
Based on this analysis, the following permitting actions are proposed for this permit:
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NPDES PERMIT FACT SHEET H.F. Lee Energy Complex
NPDES No. NC0003417
o Effluent Limit with Monitoring. The following parameters will receive a water quality -
based effluent limit (WQBEL) since they demonstrated a reasonable potential to exceed
applicable water quality standards/criteria: None.
o Monitoring Only. The following parameters will receive a monitor -only requirement
since they did not demonstrate reasonable potential to exceed applicable water quality
standards/criteria, but the maximum predicted concentration was >50% of the
allowable concentration: None.
o No Limit or Monitoring: The following parameters will not receive a limit or monitoring,
since they did not demonstrate reasonable potential to exceed applicable water quality
standards/criteria and the maximum predicted concentration was <50% of the
allowable concentration: As, Cd, Chlorides, Cr, Cu, F, Pb, Hg, Ni, Se, Zn, Ba, B, Nitrate,
and Sulfate.
316(b) REQUIREMENTS:
The site utilizes a 545 acre off -stream closed cycle cooling pond for condenser cooling and
process water. Water is withdrawn from the Neuse River to make up losses from the cooling
pond. Volume withdrawn is approximately 12 MGD. The permittee shall comply with the
Cooling Water Intake Structure Rule per 40 CFR 125.95. The permittee shall submit all the
materials required by the Rule 3.5 years from the permit effective date.
The rule requires the Director to establish interim BTA requirements in the permit on a site -
specific basis based on the Director's best professional judgment in accordance with §125.90(b)
and 40 CFR 401.14. The existing closed -cycle system at HF Lee is one of the pre -approved
compliance alternatives for impingement in accordance with §125.94(c)(1). EPA also considered
it as a pre -approved BTA for entrainment, but excluded it from the rule due to the cost
concerns. Based on this information the DEQ has determined that the existing closed -cycle
cooling system meets the requirements for an interim BTA.
INSTREAM MONITORING:
The permit requires upstream and downstream, monthly instream monitoring (upstream of
Outfall 002 - on Ferry Bridge Road, and downstream of Outfall 003 - at Stevens Mill Road
bridge) for total arsenic, total selenium, total mercury (method 1631E), total chromium,
dissolved lead, dissolved cadmium, dissolved copper, dissolved zinc, bromide, total hardness,
and total dissolved solids (TDS). In addition, the permit requires fish tissue annual monitoring
for arsenic, selenium, and mercury.
Review of the data for 2019, 2020, and 2021 indicates that all monitored parameters are either
below detection level or well below the standard. The data also shows that downstream
concentration is not significantly different from the upstream concentration for all measured
parameters.
SUMMARY OF PROPOSED CHANGES
1) Include 21 minor seeps adjacent to the cooling pond in the list of the permitted
discharges.
2) Add updated compliance boundary map approved by the NCDWR on 2/23/2022.
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NPDES PERMIT FACT SHEET H.F. Lee Energy Complex
NPDES No. NC0003417
State Contact Information
If you have any questions on any of the above information or on the attached permit, please
contact Sergei Chernikov at [phone], or [e-mail].
Page 18 of 18