NC0005363_Seep Corrective Action Plan Amendment_20220831

•
fria DUKE James Wells
ENERGY® Vice President
Environmental,Healic and Safety
Programs&Environmental Sciences
526 South Church Street
Charlotte,NC 28202
[phone]
August 24,2022 .RECEIVED
Richard Rogers
Director of Water Resources—NC DEQ 4 U G 31 2022
1617 Mail Service Center
Raleigh,NC 27699-1617 1; !;lb i l itaniffitipms
Bob Sledge
NC DEQ- Division of Water Resources
1617 Mail Service Center
Raleigh,NC 27699-1617
Subject: Report Under Special Order by Consent—EMC SOC WQ S 19-006
Duke Energy Progress, LLC—Weatherspoon Steam Station
NPDES Permit NC0005363
Seep Corrective Action Plan amendment
Dear Messrs. Rogers and Sledge:
On behalf of Duke Energy Progress, LLC(DEP), I am submitting to you the Weatherspoon
steam station Seep Corrective Action Plan Amendment as required by Section 2.)b.7)of the
subject Special Order by Consent(SOC). As detailed in the previously submitted Seep
Characterization report, no additional seep monitoring or active corrective action beyond source
removal is recommended at this time. Upon expiration of the SOC,the seeps identified by Duke
Energy as not being eligible for being dispositioned will be monitored per the requirements of
NPDES Permit NC0005363.
Please direct any questions concerning this submittal to Shannon Langley at [phone] or
[e-mail].
As required by the SOC,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 offine and imprisonment
for knowing violations.
Sincerely,
James ells
Vice P sident, Environmental, Health& Safety
Programs and Environmental Sciences
Duke Energy

t s
Messrs. Rogers and Sledge
Weatherspoon Seep Corrective Action Plan amendment
Page 2
Attachment
Weatherspoon Steam station 2022 Seep Corrective Action Plan amendment
CC: Liz Glenn/FileNet,Duke Energy via email
John Toepfer, Duke Energy via email
Kent Tyndall, Duke Energy via email
Matt Hanchey, Duke Energy via email
Shannon Langley, Duke Energy via email
Trent Allen
NC DWR
225 Green Street, Suite 714
Fayetteville,NC 28301-5095

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Science & Engineering Consultants
synTe ra synterracorp.com
SEEP MANAGEMENT PLAN
AMENDMENT TO THE CORRECTIVE ACTION PLAN
W.H. WEATHERSPOON POWER PLANT
EMC SOC WQ S19-006
491 POWER PLANT ROAD
LUMBERTON, NORTH CAROLINA 28358
AUGUST 2022
PREPARED FOR
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Seep Management Plan Amendment to the Corrective Action Plan
W.H.Weatherspoon Power Plant—Duke Energy Progress, LLC
Lumberton, North Carolina
EXECUTIVE SUMMARY
SynTerra prepared this Seep Management Plan Amendment to the Corrective Action Plan (CAP)
Part 2 (SynTerra, 2016) pertaining to the W.H. Weatherspoon Power Plant (Weatherspoon or
Site) ash basin to describe plans for the management of identified seeps in a manner that
protects public health, safety, and welfare; the environment; and natural resources.This
amendment to the CAP was prepared on behalf of Duke Energy Progress, LLC (Duke Energy).
Current data indicate seep concentrations remain in compliance with 02B standards. It is Duke
Energy's position that no additional active corrective action beyond continued source control
via ash basin excavation is warranted for the seeps at Weatherspoon.
Special Order by Consent (SOC) WQ 519-006, approved on January 27, 2020, addresses the
management of seeps during the process of basin closure under the Coal Ash Management Act
of 2014, North Carolina General Statutes 130A-309.200 through 130A-309.231, and the federal
Coal Combustion Residuals (CCR) Rule, 40 CFR Parts 257 and 261. Section 2.b.7 of the SOC
states:
No later than August 31, 2022, (60 days following the submittal of the Seep
Characterization Report for the Facility), Duke Energy shall submit a complete
and adequate proposed amendment to the groundwater Corrective Action Plan
and/or Closure Plan as appropriate for the Weatherspoon Facility describing how
any seeps identified in the Seep Characterization Report will be managed in a
manner that will be sufficient to protect public health, safety, and welfare, the
environment, and natural resources...
Findings in the Seep Characterization Report(SynTerra, 2022) indicate identified seeps are
either: (1) previously dispositioned as determined by the North Carolina Department of
Environmental Quality(NCDEQ) Division of Water Resources (DWR) at the time of issuance of
the SOC; (2) a candidate for dispositioning due to dry conditions observed for at least three
consecutive quarters; or(3) flow to an engineered collection channel that is monitored in
accordance with National Pollutant Discharge Elimination System (NPDES) Permit NC0005363.
The CAP Part 2 (SynTerra, 2016) determined monitored natural attenuation to be the optimal
corrective action for groundwater restoration at the Site following basin closure. Constituent of
interest(CO1) concentrations in groundwater were in compliance with North Carolina
Administrative Code (NCAC),Title 15A, Subchapter 02L, Groundwater Classification and
Standards (02L) and surface water was in compliance with NCAC,Title 15A, Subchapter 02B,
Surface Water and Wetland Standards (02B).Therefore, corrective action, other than ash basin
closure and potentially monitored natural attenuation, was not recommended at the time of
the CAP submittal. In a July 15, 2021 letter to Duke Energy, NCDEQ DWR provided comments on
the CSA Update (SynTerra, 2020) and stated that groundwater corrective action for the ash
basin is not required at this time.
August 2022 Page ES-1
Project:00.0066.17

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Seep Management Plan Amendment to the Corrective Action Plan
W.H.Weatherspoon Power Plant—Duke Energy Progress, LLC
Lumberton, North Carolina
Duke Energy continues to implement ash basin closure and corrective action activities that
affect groundwater seepage in a manner that is protective of public health, safety and welfare,
the environment, and natural resources. As previously noted, current data indicate seep
concentrations remain in compliance with 02B standards. Evaluation of constituent
concentrations at seep locations using the Mann-Kendall trend test demonstrates
predominantly stable and decreasing trends. This evaluation indicates that the system has been
geochemically stable prior to, and since, implementation of ash basin closure activities.
Seeps S-01, S-02, S-03, and 5-10 were requested to be dispositioned in the Seep
Characterization Report (SynTerra, 2022). Nine non-dispositioned seeps located along the ash
basin berm are monitored in accordance with NPDES Permit NC0005363. Flow contributions
from those seeps are monitored at Outfall 115A per permit requirements. Continued
dewatering and removal of CCR material from ongoing closure of the ash basin is anticipated to
eliminate flow at those seeps.
No additional seep monitoring is recommended at this time. Non-dispositioned seeps are
monitored in accordance with the NPDES permit and as required by the SOC until termination
of the SOC by DWR. Upon termination of the SOC, the non-dispositioned seeps would be
monitored per the requirements of NPDES Permit NC0005363.
Ash basin closure activities are ongoing. Based on those activities and the findings presented in
the Seep Characterization Report(SynTerra, 2022) and in this Seep Management Plan, with
DWR concurrence on seep dispositional status, additional corrective action beyond the planned
basin closure by Weatherspoon.
activities is not warranted at Weathers oon.
August 2022 Page ES-2
Project:00.0066.17

Seep Management Plan Amendment to the Corrective Action Plan
W.H.Weatherspoon Power Plant—Duke Energy Progress, LLC
Lumberton, North Carolina
TABLE OF CONTENTS
SECTION PAGE
EXECUTIVE SUMMARY ES-1
1.0 INTRODUCTION 1-1
1.1 Background 1-1
1.2 Purpose and Scope 1-1
1.3 Previous Reporting 1-2
2.0 OVERVIEW OF SEEPS PROPOSED FOR MANAGEMENT 2-1
3.0 PROPOSED SEEP MONITORING PLAN 3-1
3.1 Seeps Associated with the Ash Basin 3-1
3.2 Nature and Extent of Source Related Constituents and Seeps 3-1
3.3 Ash Basin Closure and Corrective Action 3-2
3.4 Mann-Kendall Trend Test Analysis 3-2
3.5 Seep Corrective Action Strategy 3-3
3.6 Seep Monitoring 3-3
4.0 REFERENCES 4-1
LIST OF FIGURES
Figure 1-1 Site Location Map
Figure 2-1 Existing Seep Locations and Inspection Areas
Figure 3-1 Proposed Seep Dispositional Status and Locations
Figure 3-2 Conceptual Site Model - Boron
LIST OF TABLES
Table 2-1 Seep Status Summary
Table 3-1 Seep Characterization Sampling Results—March 2022
LIST OF APPENDICES
Appendix A SOC WQ S19-006
Appendix B Mann-Kendall Trend Test Analysis, August 2022
Pp Y g
August 2022 Page i
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Seep Management Plan Amendment to the Corrective Action Plan
W.H.Weatherspoon Power Plant—Duke Energy Progress, LLC
Lumberton, North Carolina
LIST OF ACRONYMS
02B North Carolina Administrative Code,Title 15A, Subchapter 02B, Surface
Water and Wetland Standards
02L North Carolina Administrative Code,Title 15A, Subchapter 02L, Groundwater
Standards
CAP Corrective Action Plan
CCR coal combustion residual
COI constituents of interest
CSA Comprehensive Site Assessment
DWR Division of Water Resources
Duke Energy Duke Energy Progress, LLC
NCAC North Carolina Administrative Code
NCDEQ North Carolina Department of Environmental Quality
NPDES National Pollutant Discharge Elimination System
SOC Special Order by Consent
TDS total dissolved solids
Weatherspoon W.H. Weatherspoon Power Plant
WOS Waters of the State
WOTUS Waters of the United States
August 2022 Page ii
Project:00.0066.17

T 1
Seep Management Plan Amendment to the Corrective Action Plan
W.H.Weatherspoon Power Plant—Duke Energy Progress, LLC
Lumberton, North Carolina
1.0 INTRODUCTION
SynTerra prepared this Seep Management Plan Amendment to the Corrective Action Plan (CAP)
(SynTerra, 2016) pertaining to the W.H. Weatherspoon Power Plant (Weatherspoon or Site) ash
basin to describe plans to manage identified seeps in a manner that protects public health,
safety, and welfare; the environment; and natural resources.This amendment to the CAP was
prepared on behalf of Duke Energy Progress, LLC (Duke Energy). It is Duke Energy's position
that no additional active corrective action beyond continued source control by excavation of
the ash basin is warranted for seeps identified at Weatherspoon.
1.1 Background
Special Order by Consent (SOC) WQ S19-006, approved on January 27, 2020, addresses
management of seeps associated with the ash basin during the process of basin closure under
the Coal Ash Management Act of 2014, North Carolina General Statutes 130A-309.200 through
130A-309.231, and the federal Coal Combustion Residuals (CCR) Rule, 40 CFR Parts 257 and
261. The SOC is provided in Appendix A.
CCR were sluiced to the ash basin. Ash basin construction began in the 1950s, and the ash basin
was expanded in phases until 1979. CCR flows to the ash basin system ceased in 2011 with the
retirement of the coal-fired units. In preparation for ash basin closure, decanting of free water
from the ash basin began in September 2017 and was completed in December 2017.
Dewatering of ash pore water began in September 2017 and is ongoing. Excavation of the ash
basin began in September 2017 and is ongoing. A site location map is provided on Figure 1-1.
1.2 Purpose and Scope
As required in Section 2.b.7 of the SOC, this Seep Management Plan Amendment to the CAP
describes plans to manage seeps identified in the Seep Characterization Report (SynTerra,
2022) in a manner that will protect public health, safety, and welfare; the environment; and
natural resources.The Seep Characterization Report evaluated seeps based on the physical
status, chemical composition, and jurisdictional determination. To be considered for corrective
action in this Seep Management Plan, a seep must:
1) Be non-dispositioned
2) Constitute, or flow to Waters of the State (WOS) or Waters of the United States
(WOTUS)
3) Exhibit constituent concentrations that are greater than applicable North Carolina
Administrative Code (NCAC),Title 15A, Subchapter 02B, Surface Water and Wetland
Standards (02B)
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Seep Management Plan Amendment to the Corrective Action Plan
W.H.Weatherspoon Power Plant—Duke Energy Progress, LLC
Lumberton, North Carolina
1.3 Previous Reporting
Detailed descriptions of previous Site and SOC assessments and characterizations are
documented in the following:
• Comprehensive Site Assessment Report—W.H. Weatherspoon Power Plant—SynTerra,
August 2015
• Corrective Action Plan Part 1—W.H. Weatherspoon Power Plant—SynTerra, November
2015
• Corrective Action Plan Part 2—W.H. Weatherspoon Power Plant—SynTerra, February
2016
• Comprehensive Site Assessment Supplement 1—W.H. Weatherspoon Power Plant—
SynTerra, July 2016
• Surface Water Evaluation to Assess 15A NCAC 02B .0200 Compliance for
Implementation of Corrective Action Under 15A NCAC 02L .0106 (k) and (I)—SynTerra,
July 2020
• Comprehensive Site Assessment Update, W.H. Weatherspoon Power Plant—SynTerra,
August 2020
• 2020 Annual Seep Report, W.H. Weatherspoon Power Plant—SynTerra, April 2021
• 2021 Annual Seep Report, W.H. Weatherspoon Power Plant—SynTerra, April 2022
• Final Seep Report, W.H. Weatherspoon Power Plant—SynTerra,April 2022
• Seep Characterization Report, W.H. Weatherspoon Power Plant—SynTerra,June 2022
August 2022 Page 1-2
Project:00.0066.17

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Seep Management Plan Amendment to the Corrective Action Plan
W.H.Weatherspoon Power Plant—Duke Energy Progress, LLC
Lumberton, North Carolina
2.0 OVERVIEW OF SEEPS PROPOSED FOR MANAGEMENT
According to the SOC,there were 16 identified non-constructed seeps associated with the ash
basin. Of those 16 non-constructed seeps, eight seeps (S-04, S-06, S-07, S-08, S-9, S-15, S-18,
and S-22) were dispositioned at the issuance of the SOC.Two monitoring locations were
established in the SOC (S-05 and S-16). Four seeps (S-01, S-02, S-03, and S-10) were proposed to
be dispositioned in the Seep Characterization Report(SynTerra, 2022).
The remaining non-dispositioned seeps are comprised of both non-constructed (S-23 and S-24)
and constructed seeps (S-11, S-12,S-13, S-14, S-25, S-26, and S-27). Contributions and flow for
each of those seeps are to an engineered collection channel and are monitored by National
Pollutant Discharge Elimination System (NPDES)-permitted internal Outfall 115A. Flow
contributions from those seeps are regulated and monitored in accordance with NPDES permit
requirements contained in permit number NC0005363. Flow volume has already decreased
because of ash basin dewatering and excavation, and it is anticipated that flow volume will
continue to decrease or cease. For those reasons, the non-dispositioned seeps do not warrant
additional corrective action.
Seep descriptions and status are provided in Table 2-1 and seep locations are shown on
Figure 2-1.
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Seep Management Plan Amendment to the Corrective Action Plan
W.H.Weatherspoon Power Plant—Duke Energy Progress, LLC
Lumberton, North Carolina
3.0 PROPOSED SEEP MONITORING PLAN
3.1 Seeps Associated with the Ash Basin
Duke Energy continues to implement ash basin closure activities to reduce groundwater
seepage. Source control is the primary remedy for managing seeps associated with the ash
basin. Source control is conducted in a manner that is protective of public health, safety, and
welfare; the environment; and natural resources. Completed and ongoing ash basin closure
activities, implemented by Duke Energy, are detailed in Section 3.3. Continued dewatering and
removal of CCR material from ongoing closure of the ash basin is anticipated to further reduce
or eliminate seepage flow.The nature and extent of identified seeps, effects of ash basin
closure, and details about proposed monitoring are discussed in the following subsections.
There are seven constructed, non-dispositioned seeps (S-11, S-12, S-13, S-14, S-25, S-26, and 5-
27), two non-constructed, non-dispositioned seeps (S-23 and S-24), and two monitoring
locations (5-05 and S-16) associated with the Weatherspoon ash basin.The nine non-
dispositioned seeps are monitored in accordance with NPDES Permit NC0005363, and flow
contributions from those seeps are monitored at Outfall 115A per permit requirements. 5-05
and S-16 are used as water quality monitoring locations. Seeps proposed for disposition in the
Seep Characterization Report (SynTerra, 2022), non-dispositioned seeps, and water quality
monitoring locations are depicted on Figure 3-1.
3.2 Nature and Extent of Source Related Constituents and Seeps
Based on groundwater data collected through March 2020, constituents of interest (COls)
associated with the ash basin include (SynTerra, 2020):
• Arsenic • Manganese • Total dissolved solids (TDS)
• Beryllium • Molybdenum • Thallium
• Boron • Strontium • Uranium
• Cobalt • Sulfate • Vanadium
• Iron • Total Radium
(229/228)
Of those COls, arsenic, boron, sulfate, thallium, and TDS are SOC Attachment B surface water
constituents with 02B standards or in-stream target values.
Boron analytical results greater than groundwater background concentrations represent the
extent of affected groundwater (Figure 3-2). Because boron is non-reactive and mobile in
groundwater, it has been identified as a leading-edge indicator and is representative of the
overall plume that contains other COls greater than comparison criteria [02L standard or
background concentrations, whichever is greater]. Boron concentrations found in groundwater
at the ash basin is discussed below.
August 2022 Page 3-1
Project:00.0066.17

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Seep Management Plan Amendment to the Corrective Action Plan
W.H.Weatherspoon Power Plant—Duke Energy Progress, LLC
Lumberton, North Carolina
The extent of affected groundwater associated with the ash basin is limited to areas
downgradient of the basin, between the waste boundary and the cooling pond (Figure 3-2).The
area of affected groundwater in the ash basin area generally flows southeast toward the
cooling pond, the area of groundwater discharge. Boron concentrations greater than the
groundwater background threshold value have been observed in water quality monitoring
location S-16 but those concentrations are less than the in-stream target value.
The most recent seep sampling event (March 2022) was evaluated in the Seep Characterization
Report (SynTerra, 2022) and results are presented in Table 3-1. Non-dispositioned seeps S-01,
S-02, S-03, and S-10 exhibited insufficient flow to collect a sample. Seeps and water quality
monitoring locations that were flowing and exhibited conditions appropriate for sampling were
sampled in March 2022. Data from those samples indicate that SOC Attachment B constituent
concentrations are less than 02B standards.
3.3 Ash Basin Closure and Corrective Action
Duke Energy continues to implement ash basin closure and corrective action activities that
provide adequate seep management and surface water protection at the Site. Completed,
ongoing, and planned corrective action and closure activities include:
Year Closure or Corrective Action-Related Activity
October 2011 Coal-fired units retired,coal ash no longer generated
November 2015 Corrective Action Plan, Part 1 submitted
February 2016 Corrective Action Plan, Part 2 submitted
December 2016 Engineered ditches surrounding ash basin are rerouted and connected;flow
directed to cooling pond
September 2017 Ash basin decanting and excavation initiated
September 2017-ongoing Ash basin dewatering and excavation
August 3,2018 NPDES Permit#NC0005363 issued
January 27,2020 Special Order by Consent(EMC SOC WQ S-19-006)issued
August 3,2020 Comprehensive Site Assessment(CSA) Update submitted
July 15,2022 CSA Update approved and comments received from NCDEQ DWR;corrective
action for ash basin is not required at this time
2017—2028 Dewatering,excavation,and closure of the ash basin
3.4 Mann-Kendall Trend Test Analysis
The Mann-Kendall trend test (Appendix B) was performed to analyze how constituent
concentrations at seep locations have changed over time.The Mann-Kendall trend test
evaluates data over time to develop a statistical conclusion that pertains to trends —
increasing, decreasing, or stable — of a constituent concentration.Trend analysis was
completed for S-05 and S-16 because they were the only locations for which a sufficient
analytical dataset was available. Trend analysis results and time versus concentration plots for
parameters outlined in the SOC are presented in Appendix B.
August 2022 Page 3-2
Project:00.0066.17

Seep Management Plan Amendment to the Corrective Action Plan
W.H.Weatherspoon Power Plant—Duke Energy Progress, LLC
Lumberton, North Carolina
As described in Section 3.2, boron, a key indicator of CCR, was detected at monitoring location
5-16; however,the detected concentrations are well below the in-stream target value. Boron
concentrations measured at 5-05 and S-16 indicate a decreasing trend. Further, concentrations
of other detected constituents were less than the respective 02B standards for the March 2022
seep characterization sampling event. Overall,the results of the Mann-Kendall trend test
indicate that the system has been geochemically stable since the implementation of ash basin
closure with constituent concentrations remaining stable or decreasing over time.The Mann-
Kendall Trend Test Analysis report is provided in Appendix B.
3.5 Seep Corrective Action Strategy
To be considered for corrective action, a seep must:
1) Be non-dispositioned
2) Constitute, or flow to WOS or WOTUS
3) Exhibit constituent concentrations that are greater than applicable 02B surface water
standards
Seeps S-01, S-02, S-03, and S-10 were requested to be dispositioned in the Seep
Characterization Report(SynTerra, 2022). Nine non-dispositioned seeps located along the ash
basin berm will remain and will be monitored in accordance with NPDES Permit NC0005363.
Flow contributions from those seeps are monitored at Internal Outfall 115A per permit
requirements. Flow from those seeps is to a wastewater treatment unit(cooling pond), not to
WOS or WOTUS. Continued dewatering and removal of CCR material from ongoing closure of
the ash basin is anticipated to further reduce or eliminate flow at those seeps. Dispositioned
seeps 5-05 and S-16 are used as water quality monitoring locations in accordance with the SOC.
Current data indicate constituent concentrations in seeps remain in compliance with 02B
standards. Evaluation of constituent concentrations at seep locations using the Mann-Kendall
trend test demonstrates predominantly stable and decreasing trends.
As described in Section 3.3, ash basin closure activities are ongoing. Based on those activities
and the findings presented in the Seep Characterization Report (SynTerra, 2022) and in this
Seep Management Plan, with DWR concurrence on seep dispositional status, it is Duke Energy's
position that no additional active corrective action beyond continued source control is
warranted for the seeps at Weatherspoon.
3.6 Seep Monitoring
No additional seep monitoring is recommended at this time. Non-dispositioned seeps are
monitored in accordance with the NPDES permit and as required by the SOC until termination
of the SOC by the DWR. Upon termination of the SOC, the non-dispositioned seeps would be
monitored per the requirements of NPDES Permit NC0005363.
August 2022 Page 3-3
Project:00.0066.17

Seep Management Plan Amendment to the Corrective Action Plan
W.H.Weatherspoon Power Plant—Duke Energy Progress, LLC
Lumberton, North Carolina
4.0 REFERENCES
NCDEQ(2020). Special Order by Consent EMC SOC WQ S19-006. North Carolina Department of
Environmental Quality. Charlotte, NC. January 27, 2020.
SynTerra (2015) Comprehensive Site Assessment Report, W.H. Weatherspoon Power Plant,
August 2015
SynTerra (2015) Corrective Action Plan Part 1, W.H. Weatherspoon Power Plant, November
2015
SynTerra (2016) Corrective Action Plan Part 2, W.H. Weatherspoon Power Plant, February 2016
SynTerra (2016) Comprehensive Site Assessment Supplement 1, W.H. Weatherspoon Power
Plant, July 2016
SynTerra (2020). Surface Water Evaluation to Assess 15A NCAC 02B .0200 Compliance for
Implementation of Corrective Action Under 15A NCAC 02L .0106 (k) and (I) —SynTerra,
July 2020
SynTerra (2020). Comprehensive Site Assessment Update—W.H. Weatherspoon Power Plant,
August 2020
SynTerra (2021). 2020 Annual Seep Report, W.H. Weatherspoon Power Plant—SynTerra, April
2021
SynTerra (2022). 2021 Annual Seep Report, W.H. Weatherspoon Power Plant—SynTerra, April
2022.
SynTerra (2022). Final Seep Report, W.H. Weatherspoon Power Plant —SynTerra, April 2022
SynTerra (2022). Seep Characterization Report—W.H. Weatherspoon Power Plant, June 2022.
August 2022 Page 4-1
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Seep Management Plan Amendment to the Corrective Action Plan
W.H.Weatherspoon Power Plant—Duke Energy Progress, LLC
Lumberton, North Carolina
FIGURES
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Seep Management Plan Amendment to the Corrective Action Plan
W.H.Weatherspoon Power Plant—Duke Energy Progress, LLC
Lumberton, North Carolina
TABLES
synTerra
Science & Engineering Consultants

t I
TABLE 2-1
SEEP STATUS SUMMARY
SEEP MANAGEMENT PLAN AMENDMENT TO THE CORRECTIVE ACTION PLAN
W.H.WEATHERSPOON POWER PLANT
DUKE ENERGY PROGRESS,LLC,LUMBERTON,NC
Seep Receiving Waterbody Description SOC Monitoring
Seep to small channel north of the ash
basin,flowing west between toe of the dike
Site drainage ditch system flowing to
5-01 cooling pond and railroad tracks.Channel flows to S-09 Proposed to be dispositioned
and S-16 before entering wetland complex
and discharge to cooling pond.
Unnamed tributary to Jacob's Swamp and Seep around riprap pile on northeast side of
S-02 the Lumber River.(Diverted to cooling pond ash basin.Flow conveyed southeast in small Proposed to be dispositioned
Dec.2017) channel toward S-05.
Unnamed tributary to Jacob's Swamp and Seep on east side of the ash basin at the toe
5-03 the Lumber River.(Diverted to cooling pond of the dike.Flow conveyed southeast in Proposed to be dispositioned
Dec.2017) small channel toward S-05.
Unnamed tributary to Jacob's Swamp and Static AOW at southeast corner of ash
5-04•• the Lumber River.(Diverted to cooling pond Dispositioned per SOC
basin.Area repaired;seep eliminated.
Dec.2017)
Monitoring location;not a seep.Small
channel near southeast corner of ash basin
Unnamed tributary to Jacob's Swamp and near toe of dike.Location receives flow
from upstream locations S-02 and S-03.All
S-05"• the Lumber River.(Diverted to cooling pond flow at the location has been diverted from Dispositioned per SOC
Dec.2017)
flowing to Jacob's Swamp to now join
engineered flow near S-15.Combined flows
go to cooling pond.
Flow to ditch beyond north side of ash
S-06• Unnamed tributary to the Lumber River basin.Flows west toward S-07 and S-08. Dispositioned per SOC
From sampling-no CCR impacts.
36"stormwater pipe,west of former power
S-07• Unnamed tributary to the Lumber River plant site.From sampling-no CCR impacts. Dispositioned per SOC
36"stormwater pipe,i e' power
P west of former
S-08• Unnamed tributary to the Lumber River Dispositioned per SOC
plant site.From sampling-no CCR impacts.
Monitoring location;not a seep.Drainage
ditch between dike wall and railroad tracks.
Site drainage ditch system flowing to Receives flow from S-01 upstream,and
5-09"" cooling pond flows toward 5-16 downstream before Dispositioned per SOC
entering wetland complex and discharge to
cooling pond.
Seep located at the toe of the dike face on
the west side of the ash basin.Flow
Collection ditch flowing to NPDES permit
conveyed via ditch to engineered channel
S-10 Outfall 001 collecting toe drain discharges.All flow Proposed to be dispositioned
conveyed to cooling pond.This non-
constructed seep flows to a portion of an
NPDES wastewater treatment system.
Engineered ash basin toe drain.Flows to
Collection ditch flowing to NPDES permit collection ditch.Conveyed to cooling pond; N/A-Seep contribution analyzed in NPDES
5-11 Outfall 001 discharge regulated by NPDES permit, Permit monitoring at Outfall 001
Outfall 001.
Engineered ash basin toe drain.Flows to
Collection ditch flowing to NPDES permit collection ditch.Conveyed to cooling pond; N/A-Seep contribution analyzed in NPDES
S-12
Outfall 001 discharge regulated by NPDES permit, Permit monitoring at Outfall 001
Outfall 001.
Page 1 of 2

t a
TABLE 2-1
SEEP STATUS SUMMARY
SEEP MANAGEMENT PLAN AMENDMENT TO THE CORRECTIVE ACTION PLAN
W.H.WEATHERSPOON POWER PLANT
DUKE ENERGY PROGRESS,LLC,LUMBERTON,NC
Seep Receiving Waterbody Description SOC Monitoring
Engineered ash basin toe drain.Flows to
Collection ditch flowing to NPDES permit collection ditch.Conveyed to cooling pond; N/A-Seep contribution analyzed in NPDES
S-13 Outfall 001 discharge regulated by NPDES permit, Permit monitoring at Outfall 001
Outfall 001.
Engineered ash basin toe drain.Flows to
Collection ditch flowing to NPDES permit collection ditch.Conveyed to cooling pond; N/A-Seep contribution analyzed in NPDES
5-14 Outfall 001 discharge regulated by NPDES permit, Permit monitoring at Outfall 001
Outfall 001.
Monitoring location;not a seep.Sampling
site at end of culvert under road paralleling
Effluent channel flowing to NPDES permit south side of ash basin.Collects flows from
S-15•• Dispositioned per SOC
Outfall 001 5-02,S-03,S-05,S-10 and toe drain
discharges.Combined flows are conveyed
via engineered channel to cooling pond.
Monitoring location;not a seep.Narrow
Site drainage ditch system flowing to ditch downstream of locations S-01 and S-
5.16** cooling pond 09 conveying flow to cooling pond.Location Dispositioned per SOC
Is upstream of where ditch enters wetland
complex.
Culvert through berm,west of former
5-18' Unnamed tributary to the Lumber River power plant site.From sampling-no CCR Dispositioned per SOC
impacts.
Culvert through berm,west of former
S-22• Unnamed tributary to the Lumber River power plant site.From sampling-no CCR Dispositioned per SOC
impacts.
Small seep at toe of ash basin south side
dam.Flows to engineered channel collecting
Effluent channel flowing to NPDES permit toe drain discharges.All flow conveyed to N/A-Seep contribution analyzed in NPDES
S 23 Outfall 001 cooling pond.This non-constructed seep Permit monitoring at Outfall 001 •
flows to a portion of an NPDES wastewater
treatment system.
Small seep at toe of ash basin south side
dam.Flows to engineered channel collecting
Effluent channel flowing to NPDES permit toe drain discharges.All flow conveyed to N/A-Seep contribution analyzed in NPDES
5-24 Outfall 001 cooling pond.This non-constructed seep Permit monitoring at Outfall 001
flows to a portion of an NPDES wastewater
treatment system.
Engineered ash basin toe drain.Flows to
5-25 Collection ditch flowing to NPDES permit collection ditch.Conveyed to cooling pond; N/A-Seep contribution analyzed in NPDES
Outfall 001 discharge regulated by NPDES permit, Permit monitoring at Outfall 001
Outfall 001.
Engineered ash basin toe drain.Flows to
Collection ditch flowing to NPDES permit collection ditch.Conveyed to cooling pond; N/A-Seep contribution analyzed in NPDES
S-26 Outfall 001 discharge regulated by NPDES permit, Permit monitoring at Outfalf 001
Outfall 001.
Engineered ash basin toe drain.Flows to
Collection ditch flowing to NPDES permit collection ditch.Conveyed to cooling pond; N/A-Seep contribution analyzed in NPDES
5-27 Outfall 001 discharge regulated by NPDES permit, Permit monitoring at Outfall 001
Outfall 001.
Notes:
•Location previously investigated as a seep.Monitoring has not indicated the presence of coal combustion residuals.
••Seep dispositioned via repair and/or non-flowing condition to potentially reach Waters of the U.S.,or other,as noted.
The information provided in this table,except for the"Notes From Inspection"column,was derived from Special Order by Consent EMC SOC WQ 519-006,Attachment A.
AOW-area of wetness
CCR-coal combustion residuals
N/A-not applicable
NPDES-National Pollutant Discharge Elimination System
SOC-Special Order by Consent
Waterbody dassification"C"-Waters protected for uses such as secondary recreation,fishing,wildlife,fish consumption,aquatic life induding propagation,survival and maintenance of
biological integrity,and agriculture.
Secondary recreation includes wading,boating,and other uses involving human body contact with water where such activities take place in an infrequent,unorganized,or incidental manner.
Waterbody classification"Sw"-Swamp waters;Supplemental classification intended to recognize those waters which have low velodties and other natural characteristic which are different
from adjacent streams.
Page 2 of 2

TABLE 3-1
SEEP CHARACTERIZATION SAMPLING RESULTS-MARCH 2022
SEEP MANAGEMENT PLAN AMENDMENT TO THE CORRECTIVE ACTION PLAN •
W.H.WEATHERSPOON POWER PLANT
DUKE ENERGY PROGRESS,LLC,LUMBERTON,NC
Field Parameters Total Concentration
Analytical Parameter Specific Dissolved Oxidation
pH Temperature Reduction Turbidity' Flow Arsenic Barium' Boron' Bromide Cadmium Calcium Chloride Chromium Copper Fluoride Hardness
Conductance Oxygen' Potential
Reporting Units S.U. Deg C pmhos/cm mg/L mV NTU GPM pg/L pg/L pg/L pg/L µg/L mg/L mg/L pg/L µg/L mg/L mg/L
15A NCAC 02B(Class C,Sw) 4.3-9.0 32 NE 4.0 NE SO NE 10 21000 7300 NE NE NE 230 NE NE 1.8 NE
Location ID Sample Latitude Longitude Sample Analytical Results
Media Collection Date
S-07' Water 34.58821100 -78.97774701 03/03/2022 7.0 16 46 6.19 26 3.6 13.2 <1 U 29 <50 U <100 U <0.1 U 1.77 3.1 <1 U <2 U <0.1 U 7.82
5-16•• Water 34.58723800 -78.96953501 03/03/2022 7.0 18 245 6.38 4 6.5 10,4 1.47 59 364 <200 U <0.1 U 31.1 8.2 <1 U <2 U <0.2 U 97.2
S-18• Water 34.58780900 -78.97806901 03/03/2022 6.4 15 46 4.98 83 1.7 NM <1 U 27 <50 U <100 U <0.1 U 3.48 3.4 <1 U <2 U <0.1 U 12.1
Notes:
'Dissolved oxygen and turbidity are not required parameters per SOC Attachment B.Dissolved oxygen standard represents a minimum instantaneous measured value.
'Barium,boron,and thallium standards represent in-stream target values.
'Mercury standard of 0.012 will represents a chronic value.
'Selenium standard of 5 pg/L represents a chronic value.
'Dissolved arsenic standard of 150 pg/L represents a chronic value.
`Dissolved chromium standard of 11 pg/L represents a chronic value specific to dissolved chromium(VI).Dissolved chromium(III(standards are hardness-dependent Dissolved chromium concentrations from the March 2022 sampling event represent total dissolved chromium concentrations.
•Dispositianed per SOC
••5-16 is a monitoring location and not considered a seep,per SOC.
<-Concentration not detected at or greater than the adjusted reporting limit.
15A NCAC 02B(Class C,Sw)-Freshwaters protected for aquatic life,secondary recreation,and fish consumption(human health).Waters at W.H.Weatherspoon Power Plant are subject to Class C water quality standards and are also classified as swamp waters(Sw).
-Blue highlighted cells Indicate concentration greater than applicable 02B standard.
The dissolved nickel concentration(2.15 pg/L)In 5-16 was the only detection greater than the reporting limit fora constituent with a hardness-dependent 028 standard.Using the in-stream hardness from sample location S-I6,the calculated chronic hardness-dependent 028 standard for dissolved nickel at 5-16 is 50.77 pg/L.
µg/L-micrograms per liter NCAC-North Carolina Administrative Code
!mhos/cm-mkromhos per centimeter NE-not established
Deg C-degrees Celsius NM-not measured
Eh-oxidation reduction potential NTU-Nephelometric Turbidity unit
GPM-gallons per minute S.U.-standard units
ND-hardness-dependent calculated standard SOC-Special Order by Consent
mg/L-milligrams per liter U-Analyte was analyzed for,but not detected above the minimum detectable concentration(MDC).
mg-N/L-milligrams nitrogen per liter
Page 1 of 2

TABLE 3-1 III
SEEP CHARACTERIZATION SAMPLING RESULTS-MARCH 2022
SEEP MANAGEMENT PLAN AMENDMENT TO THE CORRECTIVE ACTION PLAN •
W.H.WEATHERSPOON POWER PLANT
DUKE ENERGY PROGRESS,LLC,LUMBERTON,NC
Total Concentration(Continued) Dissolved Concentration
Analytical Parameter Nitrate a Oil and Total Total Arsenics Cadmium Chromium' Copper Lead Nickel Zinc
Lead Magnesium mercury' Nickel Selenium Sulfate Thallium' Dissolved Suspended Zinc
Nitrite Grease
Solids Solids (OASµ) (0.45µ) (0.45µ) (0.45µ) (0.450 (0.45µ) (OASµ)
Reporting Units pg/L mg/L pg/L µg/L mg-N/L mg/L µg/L mg/L µg/L mg/L mg/L µg/L µg/L µg/L µg/L µg/L µg/L pg/L pg/L
15A NCAC 02B(Class C,Sw) Mr - -
Location ID Memdp�a Latitude Longitude Coilecti�le
Date Analytical Results
S-07• Water 34.58821100 -78.97774701 03/03/2022 <0.2 U 0.827 <0.0005 U <1 U <0.02 U <5 U <1 U 5.1 <0.2 U 26 <2.5 U <5 U <1 U <0.1 U <1 U I,<2U <0.2U <1U <5U
5-16•• Water 34.58723800 -78.96953501 03/03/2022 <0.2 U 4.76 0.000667 2.22 0.17 <5 U <1 U 52 <0.2 U 160 <2.5 U 6.78 <1 U <0.1 U <1 U I <2 U <0.2 U 2.15 <5 U
S-18• Water 34.58780900 -78.97806901 03/03/2022 <0.2 U 0.833 0.00104 <1 U 0.04 <5 U <1 U 5.1 <0.2 U 27 4.5 <5 U <1 U <0.1 U <1 U <2 U <0.2 U <1 U <5 U
Created by:T1G Checked by:JAW
Notes:
'Dissolved oxygen and turbidity are not required parameters per SOC Attachment B.Dissolved oxygen standard represents a minimum instantaneous measured value.
'Barium,boron,and thallium standards represent In-stream target values.
'Mercury standard of 0.012 pg/L represents a chronic value.
'Selenium standard of 5 µg/L represents a chronic value.
'Dissolved arsenic standard of 150 pg/L represents a chronic value.
'Dissolved chromium standard of 11 pg/L represents a chronic value specific to dissolved chromium(VI).Dissolved chromium(III)standards are hardness-dependent.Dissolved chromium concentrations from the March 2022 sampling event represent total dissolved chromium concentrations.
•Dispositioned per SOC
•5-16 Is a monitoring location and not considered a seep,per SOC.
c-Concentration not detected at or greater than the adjusted reporting limit.
15A NCAC 02B(Class C,Sw)-Freshwaters protected for aquatic life,secondary recreation,and fish consumption(human health).Waters at W.H.Weatherspoon Power Plant are subject to Class C water qualky standards and are also classified as swamp waters(5w).
-Blue highlighted cells indicate concentration greater than applicable 028 standard.
The dissolved nickel concentration(2.15 pg/L)in 5-16 was the only detection greater than the reporting limit for a constituent with a hardness-dependent 02B standard.Using the In-stream hardness from sample location S-16,the calculated chronic hardness-dependent 02B standard for dissolved nickel at S-16 is 50.77 pg/L
WI.micrograms per liter NCAC-North Carolina Administrative Code
µmhos/an-mloromhos per centimeter NE-not established
Deg C-degrees Celsius NM-not measured
Ea-oxidation reduction potential NTU-Nephelometric Turbidity unit
GPM-gallons per minute S.U.-standard units
HD-hardness-dependent calculated standard SOC Special Order by Consent
mg/L-milligrams per liter U-Mahe was analyzed for,but not detected above the minimum detectable concentration(MDC).
mg-N/L-milligrams nitrogen per liter
Page 2 of 2

f �
Seep Management Plan Amendment to the Corrective Action Plan
W.H.Weatherspoon Power Plant—Duke Energy Progress, LLC
Lumberton, North Carolina
APPENDIX A
SOC WQ S19-006
synTerra
Science & Engineering Consultants

ItaJ ,\"a
ROY COOPER 1a7' � w,
Governor 7 . 14
- ,9MICHAEL S.REGAN ' k.
Secretary • ._. .
LINDA CULPEPPER NORTH CAROLINA
Director Environmental Quality
January 27,2020
Mr. Paul Draovitch, Senior Vice President EHS
Duke Energy
526 S. Church Street Mail
Mail Code EC3XP RECEIVED
Charlotte,NC 28202
Subject: SPECIAL ORDER BY CONSENT FEB - 3 2020
SOC No. S 19-006 BY:
Duke Energy Progress, LLC ,¢�Y
Weatherspoon Plant Initial i
NPDES Permit NC0005363
Robeson County
Dear Mr. Draovitch:
Attached for your records is a copy of the Special Order by Consent(SOC)approved by the
Environmental Management Commission and signed by the Director of the Division of Water
Resources on January 27, 2020.
The terms and conditions of the SOC are in full effect,including those requiring submittal of
written notice of compliance or non-compliance with any schedule date. The following items are
brought to your attention as they pertain to the terms and conditions of the SOC:
• Payment of the upfront penalty is due no later than February 28,2020.
• Monitoring performed per the terms of the SOC shall commence during the current calendar
quarter(January- March), with results submitted to DWR no later than April 30, 2020.
Subsequent monitoring and reporting shall occur as specified in the SOC.
• Per the terms of paragraph 2.b.4, submittal of the first quarterly progress report shall be due on
July 30, 2020.
Pursuant to North Carolina General Statute 143-215.3D, water quality fees have been revised to
include an annual fee for activities covered under a Special Order by Consent. Duke Energy will be
subject to a fee of$250.00 on a yearly basis while under the Order. The initial fee payment shall be
paid no later than February 28,2020. Future annual fee invoicing will be done on an annual basis
along with the invoicing for other Duke Energy SOCs.
DE
Q) NorthCarolinaDepartment oif EnvironmentalQuality IDivisionofWaterResouces���//// 5l2 North Salisbury Street 11611 Mail Service Center I Raleigh,North Carolina 27699 1611
0/8MM"b"+°°^'""OnaNty 919.707.9000

, Mr. Paul Draovitch
S 19-006 Transmittal
• p. 2
If you have any questions concerning this matter,please contact Bob Sledge at(919) 707-3602.
Sinely�
Linda Culpepper
Attachment
cc: SOC File
ec: Fayetteville Regional Office - DWR/Water Quality Regional Operations
DWR Laserfiche Files
Shannon Langley- Duke Energy
Sara Janovitz-EPA Region 4
Jeff Poupart- DWR/WQPS

NORTH CAROLINA
ENVIRONMENTAL MANAGEMENT COMMISSION
COUNTY OF ROBESON
IN THE MATTER OF )
NORTH CAROLINA ) SPECIAL ORDER BY CONSENT
NPDES PERMIT NC0005363 )
) EMC SOC WQ S 19-006
HELD BY )
DUKE ENERGY PROGRESS, LLC )
Pursuant to the provisions of North Carolina General Statutes(G.S.) 143-215.2, this Special
Order by Consent covering seeps from the coal ash basin at the W. H. Weatherspoon Facility,is
entered into by Duke Energy Progress, LLC,hereinafter referred to as Duke Energy, and the
North Carolina Environmental Management Commission, an agency of the State of North
Carolina created by G.S. 143B-282, and hereinafter referred to as the Commission. Duke Energy
and the Commission are referred to hereafter collectively as the"Parties."
1. Stipulations: Duke Energy and the Commission hereby stipulate the following:
a. This Special Order by Consent("Special Order")addresses issues related to the
elimination of seeps(as defined in subparagraphs e, f, and g below)from Duke
Energy's coal ash basins during the separate and independent process of basin
closure under the Coal Ash Management Act, G.S. 130A-309.200 through 130A-
309.231 ("CAMA")and the Federal Coal Combustion Residuals Rule,40 CFR
Parts 257 and 261. The Environmental Protection Agency first directed
permitting authorities to consider potential impacts on surface water of seeps from
earthen impoundments in 2010. At that time,Duke Energy began discussions
with the North Carolina Department of Environmental Quality("the
Department")regarding seeps at multiple Duke Energy facilities, including
identifying certain seeps in permit applications and providing data to the
Department regarding seeps. In 2014,Duke Energy provided a comprehensive
evaluation of all areas of wetness and formally applied for NPDES permit
coverage of all seeps. Since 2014,Duke Energy has performed periodic
inspections and promptly notified the Department of new seeps and sought
NPDES permit coverage where appropriate. On March 4,2016,the Department
issued Notices of Violation("NOVs")to Duke Energy related to seeps.

` EMC SOC WQ S19-006
Duke Energy Progress,LLC
p.2
Pursuant to CAMA, Duke Energy is required to decant and dewater its coal ash
basins as part of the closure process. Decanting(i.e., removal of the free water on
the surface of the coal ash basin)has been completed at the Weatherspoon
Facility's coal ash basin. Dewatering(i.e. removal of sufficient interstitial water)
of the Weatherspoon Facility's coal ash basins will be required before the ash
basin can be closed. Removal of remaining coal ash wastewater through
dewatering is expected to substantially reduce or eliminate the seeps. In order to
accomplish this goal of substantially reducing or eliminating seeps, this Special
Order affords certain relief to Duke Energy related to the non-constructed seeps
(as defined in subparagraphs f and g below), while Duke Energy completes
activities associated with closure of the ash basins. Constructed seeps at the
Weatherspoon Facility (as defined in subparagraphs e and f below)will be
addressed in the NPDES permit. After completion of dewatering activities for a
set period of time, for any remaining seeps, whether constructed or non-
constructed, Duke Energy must take appropriate corrective action as specified
more fully below.
b. Duke Energy has been issued a North Carolina NPDES permit for operation of an
existing wastewater treatment works at the following, former coal fired electric
generation facility:
Permit Issuance Receiving Water
Facility Number CountyDate for Primary
Outfall
Weatherspoon NC0005363 Robeson 08/03/2018 Lumber River
c. Duke Energy's Weatherspoon Facility no longer generates electricity by burning
coal. A four-unit,combustion turbine electric generation system,powered by fuel
oil is located at the site. The Weatherspoon Facility has an existing ash basin and
is subject to the provisions of this Special Order.
d. Wastewater treated at coal-fired electric stations includes water mixed with ash
produced through the combustion of coal for the steam generation process. Ash is
controlled and collected through the use of water, creating a slurry that is
conveyed to impoundments or basins with earthen dike walls. In the ash basin,
the solids separate from the liquid portion,with the resulting supernatant
discharged under the terms of the NPDES permit.

EMC SOC WQ S 19-006
Duke Energy Progress,LLC
p. 3
e. The coal ash basin at the Weatherspoon Facility is unlined, having no
impermeable barrier installed along its floors or sides. Earthen basins and dike
walls are prone to the movement of liquid through porous features within those
structures through a process known as seepage. The Weatherspoon Facility
exhibits locations adjacent to, but beyond the confines of, the coal ash basin
where seepage of coal ash wastewater from the coal ash basin may intermix with
groundwater,reach the land surface(or"daylight"),and may flow from that area.
Once such seepage reaches the land surface, it is referred to as a"seep." Each of
the seeps identified at the Weatherspoon Facility and addressed in this Special
Order exhibit some indication of the presence of coal ash wastewater. Both(a)
confirmed seeps and(b) areas identified as potential seeps that were later
dispositioned, are identified in Attachment A.
f. The Weatherspoon Facility's coal ash impoundment contains constructed features
on or within the dam structures(toe drains)to collect seepage. This wastewater is
conveyed via pipes and a constructed channel directly to treatment unit covered
by the NPDES permit,with permitted discharge to a receiving water. These
discrete, identifiable,point source discharges are covered and regulated by the
NPDES permit and designated as internal outfalls therein. The characteristics of
these wastewater flows are similar to those discharging from other permitted
outfalls for ash basin effluent. In this Special Order, seeps that are (1)on or
within the dam structures and(2)convey wastewater via a pipe or constructed
channel directly to a receiving water are referred to as"constructed seeps." Seeps
that are not on or within the dam structure or that do not convey wastewater via a
pipe or constructed channel directly to a receiving stream are referred to as"non-
constructed seeps."
g. Non-constructed seeps at the Weatherspoon Facility often exhibit low flow
volume and may be both transient and seasonal in nature, and may, for example,
manifest as an area of wetness that does not flow to surface waters,a point of
origin of a stream feature, or flow to an existing stream feature. These
circumstances of the non-constructed seeps make them difficult to discern,
characterize, quantify and/or monitor as discrete point source discharges. This
creates challenges in permit development and compliance monitoring because it is
difficult to accurately monitor for flow and discharge characterization. Non-
constructed seeps at the Weatherspoon Facility present significant challenges to
their inclusion in NPDES permits as point source discharges, but they do cause or
contribute to pollution of classified waters of the State. Therefore, these non-
constructed seeps are addressed in this Special Order rather than in an NPDES
permit.

EMC SOC WQ S 19-006
Duke Energy Progress,LLC
p.4
h. A subset of these non-constructed seeps at the Weatherspoon Facility do not flow
directly to surface waters, but flow to some portion of an NPDES permitted
wastewater treatment system. In such instances,the seeps may be referenced in
NPDES permits as contributing flow to a permitted outfall. Any non-constructed
seep that falls within this subset is identified in Attachment A by the following
statement in its description: "This non-constructed seep a portion to of an
NPDES wastewater treatment system."
i. Investigations and observations conducted by the Department and U. S. Army
Corps of Engineers staff have concluded that some seeps emanating from the
Weatherspoon Facility's coal ash basin creates and/or flows into features
delineated as classified waters of the State or Waters of the United States.
j. Collectively, the flow volume from non-constructed seeps is generally low
compared to historic volumes of wastewater generated at the Weatherspoon
Facility.
k. In 2014, Duke Energy conducted a survey of each coal-fired electric generation
station to identify potential seeps from the coal ash surface impoundments. Duke
Energy included all areas of wetness identified around the impoundments as
seeps,and submitted applications to include those seeps in NPDES permits.
Beginning in 2015, Duke Energy has implemented semi-annual surveys to
identify new seeps in the vicinities of the coal ash basins. Additional seeps have
been observed and documented during these surveys and reported to the
Department pursuant to a Discharge Identification Plan mandated by CAMA.
Additional investigation has determined that not all of areas identified in 2014 are
seeps, but each Duke Energy facility does have multiple seeps.
1. The Department issued a NOV to Duke Energy on March 4,2016 for the seeps
that emanate from the unlined coal ash surface impoundment at the Weatherspoon
Facility.
m. Non-constructed seeps create conditions such that certain surface water quality
standards may not consistently be met at all Duke Energy monitoring sites.
n. The presence of coal ash influenced water in the non-constructed seeps causes or
contributes to pollution of the waters of this State, and Duke Energy is within the
jurisdiction of the Commission as set forth in G.S. Chapter 143, Article 21.
o. A list of seeps identified in the vicinities of the coal ash surface impoundments at
the Weatherspoon Facility, as well as their locations, and the bodies of water
those seeps may flow into (if applicable), can be found in Attachment A to this
Special Order.

EMC SOC WQ S19-006
Duke Energy Progress,LLC
P. 5
p. Duke Energy must close the coal ash surface impoundments at all North Carolina
coal-fired electric generating stations in accordance with applicable requirements
set out in CAMA and the Federal Coal Combustion Residuals Rule,requirements
of which are independent of the resolution of seeps addressed in this Special
Order.
q. Continued dewatering of wastewater from the coal ash basin is expected to
eliminate or substantially reduce the seeps from the ash basin at the Weatherspoon
Facility.
r. Since this Special Order is by consent,the Parties acknowledge that review of the
same is not available to the Parties in the N.C. Office of Administrative Hearings.
Furthermore,
o e,neither party shall file a petition for judicial review concerning the
terms of this Special Order.
2. Duke Energy,desiring to resolve the matters causing or contributing to pollution of the
waters of the State described above, hereby agrees to do the following:
a. Penalties
1) Upfront Penalty. As settlement of all alleged violations due to seepage at
the Weatherspoon Facility,pay the Department, by check payable to the
North Carolina Department of Environmental Quality, a penalty in the
amount of$72,000, calculated based upon$12,000 each for four
constructed seeps identified prior to January 1, 2015 and$6,000 each for
four non-constructed seeps identified prior to January 1,2015.
A certified check in the amount of$72,000.00 must be made payable to
the Department of Environmental Quality and sent to the Director of the
Division of Water Resources (DWR) at 1617 Mail Service Center,
Raleigh,North Carolina 27699-1617 by no later than thirty (30) days
following the date on which this Special Order is approved and executed
by the Commission, and received by Duke Energy.

•
EMC SOC WQ S 19-006
Duke Energy Progress,LLC
p. 6
No penalty shall be assessed for seeps identified after December 31, 2014,
given Duke Energy's inclusion of seeps in permit applications and
compliance with the Discharge Identification Plan required under CAMA.
By entering into this Special Order, Duke Energy makes no admission of
liability, violation or wrongdoing. Except as otherwise provided herein,'
payment of the upfront penalty does not absolve Duke Energy of its
responsibility for the occurrence or impacts of any unauthorized
discharges in the area of the Weatherspoon Facility that may be
discovered in the future, nor does the payment preclude DWR from taking
enforcement action for additional violations of the State's environmental
laws.
2) Stipulated Penalties. Duke Energy agrees that unless excused under
paragraph 5, Duke Energy will pay the Department,by check payable to
the North Carolina Department of Environmental Quality, stipulated
penalties according to the following schedule for failure to perform
activities described in paragraphs 2(b and c), or for failure to comply with
interim action levels listed in Attachment A.
Failure to meet a deadline in the Compliance $1,000.00/day for the first seven
Schedule in 2(b)of this Special Order days; $2,000.00/day thereafter
Failure to meet any other deadline in this $1,000.00/day for the first seven
Special Order days; $2,000.00/day thereafter
Exceedance of an interim action level listed in $4,500.00 per monitored exceedance
Attachment A
Monitoring frequency violations $1,000.00 per violation
Failure to submit,by the deadline set forth
herein,adequate amendments to groundwater
Corrective Action Plans or Closure Plans to $5,000.00 per day,to a maximum of
address all remaining seeps,through $1,000,000.00 per electric generating
corrective action as applicable under facility.
paragraph 2(b)(7)of this Special Order.2
As long as Duke Energy remains in compliance with the terms of this
Special Order, as well as CAMA and conditions of any approvals issued
thereunder,the Department shall not assess civil penalties for newly
identified seeps.
1 See especially paragraph 2(a)2 excepting newly identified seeps from future penalties under
certain conditions.
2 Failure to adequately implement any amended Corrective Action Plan or Closure Plan will be
handled in the normal course.

EMC SOC WQ S 19-006
Duke Energy Progress,LLC
P. 7
b. Compliance Schedule. Duke Energy shall undertake the following activities in
accordance with the indicated time schedule. No later than fourteen(14)calendar
days after any date identified for accomplishment of any activity,Duke Energy
shall submit to the Director of DWR written notice of compliance or
noncompliance therewith. In the case of compliance,the notice shall include the
date compliance was achieved along with supporting documentation if applicable.
In the case of noncompliance,the notice shall include a statement of the reason(s)
for noncompliance, remedial action(s)taken, and a statement identifying the
extent to which subsequent dates or times for accomplishment of listed activities
may be affected.
Duke Energy is required to comply with the requirements of G.S. § 130A-
309.216. Duke Energy is currently engaged in the reuse of CCR material from
the Weatherspoon Facility by providing the material as a raw product in the
manufacture of cement.
1) The Coal Ash Management Act(G.S. § 130A-309.210 (b))prohibited the
disposal of CCR into the basins at Duke Energy facilities where coal-fired
generating units were no longer producing CCR as of October 1, 2014.
The coal-fired generating units at the Weatherspoon Facility were retired
in 2011.
2) The cessation of inflows at the Weatherspoon Facility resulted in an
immediate reduction of the amount of free water in the basin such that
additional decanting was not pursued.
3) Removal of interstitial water will be required in order to excavate the ash
for the purpose of its removal from the Weatherspoon Facility. Duke
Energy has begun the process of removal of interstitial water from the
Weatherspoon Facility and will continue as needed to support the ash
reuse project described above.
4) Beginning with the first complete calendar quarter that occurs following
the effective date of this Consent Order, Duke Energy shall provide
reports on the status of dewatering work and other activities undertaken
with respect to excavation of the Weatherspoon Facility's coal ash surface
impoundment to DWR. The quarterly reports are due by April 30,July
30, October 30, and January 30. The reports are to be submitted as
follows: one copy must be mailed to DWR's Fayetteville Regional Office
Supervisor, 225 Green Street, Suite 714,Fayetteville,NC 28301-5095,
and one copy must be mailed to the Water Quality Permitting Program,
Division of Water Resources, 1617 Mail Service Center,Raleigh NC
27699-1617. The quarterly reporting requirement shall remain in force
until completion of two years of coal ash excavation operations.

' * EMC SOC WQ S 19-006
Duke Energy Progress,LLC
p. 8
5) Duke Energy shall conduct annual comprehensive surveys of areas down
gradient of the ash basins, identifying new seeps, and documenting the
physical characteristics of previously documented seeps. All
examinations of seeps must include identification of seeps by approximate
latitude and longitude and date-stamped digital photographs of their
appearance. A report summarizing the findings of the surveys, including a
section analyzing the effect dewatering of the basin has on seep flows,
accompanied by copies of the photographs noted above("Annual Seep
Report"), shall be submitted to DWR in conjunction with submittal of the
April 30 quarterly reports noted in 2(b)(4). This Annual Seep Report must
list any seep that has been dispositioned(as described below)during the
previous year, including an analysis of the manner of disposition. For
purposes of this Special Order, "dispositioned"includes the following: (1)
the seep is dry for at least three consecutive quarters; (2)the seep does not
constitute, and does not flow to, waters of the State or Waters of the
United States for three consecutive quarters; (3)the seep is no longer
impacted by flow from any coal ash basin as determined by the Director of
DWR in accord with applicable law and best professional judgment; or(4)
the seep has been otherwise eliminated(e.g.,through an engineering
solution). If a seep that has been dispositioned through drying up
reappears in any subsequent survey, such a seep will no longer be deemed
dispositioned and can be subsequently re-dispositioned as specified above.
6) No later than April 30, 2022 (90 days following the completion of two
years of CCR removal activities under the terms of this Special Order(to
include excavation and dewatering)at the Weatherspoon Facility), and in
the same manner as in the annual surveys, Duke Energy shall conduct a
comprehensive survey of areas down gradient of ash basin at the
Weatherspoon Facility,identifying new seeps,and documenting the
physical characteristics of previously documented seeps. All
examinations of seeps must include identification of seeps by approximate
latitude and longitude and date-stamped digital photographs of their
appearance. A report summarizing the findings of this survey, including a
section analyzing the effect decanting and dewatering of the basin has had
on seep flows, accompanied by copies of the photographs noted above,
shall be submitted to the Director of DWR("Final Seep Report"). This
Final Seep Report must list any seep that has been dispositioned(as
described in subparagraph(5)above)during decanting,dewatering and
CCR removal or beneficiation processes, including an analysis of the
manner of disposition. The determination of whether a seep is
dispositioned rests with the Director of DWR. At, or at any time prior to,
submission of the Final Seep Report, Duke Energy shall seek formal
certification from the Director of DWR, certifying the disposition of any
seep that Duke Energy has characterized as dispositioned. Any seeps not
certified as dispositioned by the Director of DWR shall not be deemed as
dispositioned.

EMC SOC WQ S 19-006
Duke Energy Progress,LLC
P.9
7) If by the date specified in subparagraph(6) above, any seeps(including
• both constructed and non-constructed seeps)have not been certified by the
Director of DWR as dispositioned(as described in subparagraph(5)
above), Duke Energy shall conduct a characterization of those seeps.3
Duke Energy shall submit a report on the findings of these
characterizations("Seep Characterization Report")to the Director of
DWR no later than June 30,2022. The Seep Report Re ort must
include all sampling data for each remaining seep as well as Duke
Energy's evaluation of the jurisdictional status of all seeps at the
Weatherspoon Facility. The determination regarding whether a surface
water feature is a classified water of the State rests with DWR.
No later than August 31, 2022 (60 days following the submittal of the
SeepCharacterization
zation Report), Duke Energy shall submit a complete and
adequate proposed amendment to the groundwater Corrective Action Plan
and/or Closure Plan as appropriate for the Weatherspoon Facility
describing how any seeps identified in the Seep Characterization Report
will be m ana ed in a manner that will be sufficient toprotect
g public
health, safety, and welfare, the environment, and natural resources. This
proposed amendment will go to public comment. Duke Energy shall
submit documentation that the proposed modification has been submitted
to the appropriate division within the Department that has authority for
approving modification of the groundwater Corrective Action Plan and/or
Closure Plan. The content of, and DEQ's review of, an amendment to a
groundwater Corrective Action Plan shall be consistent with Title 15A,
Chapter 2L of the N.C. Administrative Code (specifically including
2L.0106(h)-(o)). The amendment to the Corrective Action Plan and/or
Closure Plans shall be implemented by Duke Energy in accordance with
the deadlines contained therein, as approved or conditioned by the
Department. Failure by Duke Energy to implement the amendment will
be handled in the normal course by the Department in accordance with its
enforcement procedures(i.e., outside this Special Order).
3 If any seep is dispositioned between the time that the Final Seep Report is submitted and the
time the Seep Characterization Report is submitted, an analysis of the manner of disposition
must be included in the Seep Characterization Report, and Duke Energy must seek certification
of such a disposition from the Director of DWR. Only if such certification is received prior to
the due date of the proposed amendment described in paragraph 2(b)(7)may such a seep,
certified as dispositioned,be omitted from the proposed amendment.

EMC SOC WQ S 19-006
Duke Energy Progress,LLC
p. 10
•
8) Termination of Special Order
This Special Order shall terminate on the later of the following dates:
• Certification that all seeps have been eliminated.
• 30 days following the approval of an amended groundwater
Corrective Action Plan and/or Closure Plan as appropriate (if an
amendment is submitted in compliance with subparagraph (7)
above).
For clarity, listed below is a summary of the timetable for the documents due in
accordance with the terms of this Special Order:
Document Due Date
Final Seep Report April 30, 2022
Seep Characterization Report June 30, 2022
Proposed amendment to groundwater
Corrective Action Plan and/or Closure August 31, 2022
Plan
c. Interim Action Levels.
1) Duke Energy shall perform monitoring of waters receiving flow from non-
constructed seeps in accordance with the schedules listed in Attachments
A and B, except as noted in paragraph 2(c)(2)below.
2) If the monitoring of any classified water of the State receiving flow from
seeps regulated by this Special Order indicates exceedance of any interim
action level established by the Special Order,Duke Energy shall increase
monitoring at that location from quarterly to monthly until concentrations
of monitored characteristics return to those observed at the initiation of the
Special Order. If any interim action level established by the Special Order
is exceeded by more than 20%in a single sampling event,or exceeded for
two (2) consecutive monitoring events, in addition to paying the
associated stipulated penalty, Duke Energy shall conduct a re-assessment
of the contributing seep(s), including, but not limited to, evaluation of
proposed remedial actions for treatment and/or control of the seep such
that impacts to the receiving waters are quickly mitigated. A report
compiling the findings of the re-assessment, including proposed remedial
actions, shall be provided to the Director of DWR within 60 days of any
applicable exceedance. Following its review,DWR shall notify Duke
Energy of its concurrence or disapproval of Duke Energy's proposed
remedial actions.

EMC SOC WQ S19-006
Duke Energy Progress,LLC
p. 11
3) Upon the complete execution of this Special Order,with regard to non-
constructed seeps, interim action levels for the receiving waters (which are
minor tributaries)are hereby established as noted in Attachment A. The
interim action levels are site-specific. Duke Energy shall monitor at
approved sampling sites to ensure interim action levels are met. Interim
action levels shall remain effective in the designated surface waters until
the applicable termination date in paragraph 2(b)(8)is reached.
4) Mo
nitoring associated with seeps covered bythis Special Order
p p is exempt
from the electronic reporting requirements associated with NPDES
permits. Results of monitoring required exclusively per the terms of this
Special Order shall be reported to the Director of DWR in a
spreadsheet/worksheet format agreed to by Duke Energy and DWR.
Monitoring data shall be submitted to the Director of DWR in a digital
format no rater than 30 days following the end of each calendar quarter for
as long as the Special Order is in effect. Monitoring data shall be sent to
the following email address: [e-mail]. Data from those
sites with monitoring required exclusively per the terms of the Special
Order will be posted on DWR's website to provide the public with the
opportunity for viewing.
3. Duke Energy will continue to operate its coal ash surface impoundment in such a manner
that its performance is optimized,and potential for surface waters to be affected by seeps
is minimized.
4. Duke Energy shall make available on its external website the NPDES permits,this
Special Order and all reports required under this Special Order for the Weatherspoon
Facility no later than thirty(30) days following their effective or submittal dates.
5. Duke Energy and the Commission agree that the stipulated penalties specified in
paragraph 2(a)(2) are not due if Duke Energy satisfies DWR that noncompliance was
caused solely by:
a. An act of God;
b. An act of war;
c. An intentional act or omission of a third party,but this defense shall not be
available if the act or omission is that of an employee or agent of Duke Energy or
if the act or omission occurs in connection with a contractual relationship with
Duke Energy;

EMC SOC WQ S 19-006
Duke Energy Progress,LLC
p. 12
d. An extraordinary event beyond the Duke Energy's control, specifically including
any court order staying the effectiveness of any necessary permit or approval.
Contractor delays or failure to obtain funding will not be considered as events
beyond Duke Energy's control; or
e. Any combination of the above causes.
6. Failure within thirty (30) days of receipt of written demand by DWR to pay the stipulated
penalties, or challenge them by a contested case petition pursuant to G.S. 150B-23, will
be grounds for a collection action, which the Attorney General is hereby authorized to
initiate. The only issue in such an action will be whether the thirty(30)days has elapsed.
7. Any non-constructed seeps causing or contributing to pollution of waters of the State
associated with the coal ash impoundment at Duke Energy's Weatherspoon Facility, and
listed in Attachment A to this Special Order, are hereby deemed covered by this Special
Ord
er. Any newly-identified non-constructed seeps discovered while this Special Order
is in effect,and timely reported to the Department per the terms of CAMA and this
Special Order,shall be deemed covered by the terms of the Special Order, retroactive to
the time of their discovery. Newly-identified non-constructed seeps must be sampled for
the presence of those characteristics listed in Attachment B to this Order. Newly-
identified non-constructed seeps found to be causing or contributing to pollution of the
waters of the State, with the effe
ct of causinga violation of water qualitystandards
in
surface waters not already referenced in the Special Order,may require modification of
the Special Order to address those circumstances.
8. Noncompliance with the terms of this Special Order is subject to enforcement action in
addition to the above stipulated penalties, including,but not limited to injunctive relief
pursuant to G.S. 143-215.6C or termination of this Special Order by the Director of DWR
upon ten (10)days' notice to Duke Energy. Noncompliance p lance with the terms of this
Y gY p
Special Order will not be subject to civil penalties in addition to the above stipulated
penalties.
9. This Special Order and any terms or conditions contained herein, hereby supersede any
and all previous Special Orders, Enforcement Compliance Schedule Letters, terms,
conditions,and limits contained therein issued in connection with NPDES permit
NC0005363.
10. This Special Order may be modified at the Commission's discretion,provided the
Commission is satisfied that Duke Energy has made good faith efforts to secure funding,
complete all construction, and achieve compliance within the dates specified. In
accordance with applicable law, modification of this Special Order will go to public
notice prior to becoming effective.
11. Failure to pay the up-front penalty within thirty (30) days of execution of this Special
Order will terminate this Special Order.

EMC SOC WQ S 19-006
Duke Energy Progress,LLC
p. 13
12. In addition to any other applicable requirement,each report required to be submitted by
Duke Energy under this Special Order shall be signed by a plant manager or a corporate
official responsible for environmental management and compliance, and shall include the
following certification:
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 fine and
imprisonment for knowing violations.
13. This Special Order shall become effective in accordance with state law, and once
effective, Duke Energy shall comply with all schedule dates, terms, and conditions
herein.

EMC SOC WQ S 19-006
Duke Energy Progress,LLC
p. 14
This Special Order by Consent shall expire no later than August 31,2023.
For Duke Energy Progress,LLC:
‘a/S—Aq
Paul Draovitch Date
Senior Vice President,Environmental,Health& Safety
For the North Carolina Environmental Management Commission:
govlo
Dr.A. Stanley Meiburg,Chai Date
NC Environmental Management Commission

Attachment A _
S19-006
Duke Energy Progress, LLC—Weatherspoon Steam Station, p. 1
Constructed Seeps
See p ID Approximate Location Receiving
Coordinates Description Receiving Interim Action
pon
Number Waterbody Waterbody SOC Monitoring Levels
Latitude Longitude Classification
Collection
Engineered ash basin toe drain. Flows N/A—Not a N/A—Seep contribution
to collection ditch. Conveyed to coolingditch flowing N/A—Not a
S-11 34.588537 -78.968071 Y Classified analyzed in NPDES Classified Surface
pond;discharge regulated byNPDES to NPDES
g g Surface Permit monitoring at
permit Water
permit, outfall 001. _ outfall 001 Water Outfall 001
Collection
Engineered ash basin toe drain.Flows N/A—Not a N/A—Seep contribution
to collection ditch.Conveyed to coolingditch flowing N/A—Not a
S-12 34.588729 -78.967785 Y Classified analyzed in NPDES Classified Surface
pond;discharge regulated byNPDES to NPDES
g g Surface Permit monitoring at
permit,outfall 001. permit Water
outfall 001 Water Outfall 001
Collection
Engineered ash basin toe drain. Flows N/A—Not a N/A—Seep contribution
to collection ditch.Conveyed to coolingditch flowing N/A—Not a
S-13 34.588896 -78.967469 Y Classified analyzed in NPDES
pond;discharge regulated byNPDES to NPDES Classified Surface
g g Surface Permit monitoring at
permit,outfall 001. permit Water Outfall 001 Water
outfall 001
Collection
Engineered ash basin toe drain. Flows N/A—Not a N/A—Seep contribution
ditch flowing N/A—Not a
S 14 34.589052 -78.967185 to collection ditch.Conveyed to cooling Classified analyzed in NPDES
pond;discharge regulated byNPDES to NPDES Classified Surface
p � g g Surface Permit monitoring at
permit,outfall 001. permit Water Outfall 001 Water
outfall 001
Engineered ash basin toe drain. Flows Collection
ditch flowing N/A—Not a N/A—Seep contribution N/A—Not a
to collection ditch.Conveyed to cooling Classified analyzed in NPDES
S-25 34.588819 -78.967677 to NPDES Classified Surface
pond;discharge regulated by NPDES Surface Permit monitoring at
permit,outfall 001. permit Water
outfall 001 Water Outfall 001
*Location previously investigated as a seep. Monitoring has not indicated the presence of coal combustion residuals.
**Seep dispositioned via repair and/or non-flowing condition to potentially reach WOTUS,or other,as noted.
Monitoring shall be conducted at the approximate locations indicated on the attached site map.
All monitoring shall be conducted per the requirements found in Attachment B of this Order.

Attachment A
S19-006
Duke Energy Progress, LLC—Weatherspoon Steam Station, p. 2
Constructed Seeps
See ID Approximate Location Receiving
p Coordinates Receiving Interim Action
Number Description Waterbody Waterbody SOC Monitoring
Latitude Longitude Classification Levels
Collection
Engineered ash basin toe drain. Flows N/A—Not a N/A—Seep contribution
to collection ditch.Conveyed to coolingditch flowing N/A—Not a
S-26 34.588953 -78.967433 Y Classified analyzed in NPDES Classified Surface
pond;discharge regulated byNPDES to NPDES
g g Surface Permit monitoring at
permit,outfall 001. permit Water Outfall 001 Water
outfall 001
Collection
Engineered ash basin toe drain. Flows N/A—Not a N/A—Seep contribution
to collection ditch.Conveyed to coolingditch flowing N/A—Not a
S-27 34.589078 -78.967197 Y Classified analyzed in NPDES
pond;discharge regulated byNPDES to NPDES Classified Surface
g g Surface Permit monitoring at
permit,outfall 001. permit Water
outfall 001 Water Outfall 001
*Location previously investigated as a seep. Monitoring has not indicated the presence of coal combustion residuals.
**Seep dispositioned via repair and/or non-flowing condition to potentially reach WOTUS, or other,as noted.
Monitoring shall be conducted at the approximate locations indicated on the attached site map.
All monitoring shall be conducted per the requirements found in Attachment B of this Order.

Attachment A
S19-006
Duke Energy Progress, LLC—Weatherspoon Steam Station, p. 3
Non-Constructed Seeps
Seep ID Approximate Location Receiving
Coordinates Description Receiving Interim Action
Number p Waterbody Waterbody SOC Monitoring Levels
Latitude Longitude Classification
Seep to small channel north of the ash ba In, Site
flowing west between toe of the dike and drainage Monitoring at
S-01 34.593324 -78.973004 railroad tracks.Channel flows to S-09 and S- ditch system established Duke
flowing to C,Sw EnergyS-16 See S-16
16 before entering wetland complex and
discharge to cooling pond. cooling monitoring site
pond
Unnamed
Tributary Monitoring at
Seep around riprap pile on northeast side of (UT)to location S-05,
S-02 34.593513 -78.969757 ash basin. Flow conveyed southeast in small Jacob's C;Sw prior to joining See S-05
channel toward S-05 Swamp and other flows at
the Lumber S-15.
River
UT to Monitoring at
Seep on east side of the ash basin at the toe Jacob's location 5-05,
5-03 34.591892 -78.967913 of the dike. Flow conveyed southeast in Swamp and C;Sw prior to joining See S-0S
small channel toward 5-05. the Lumber other flows at
River S-15.
UT to
** Static AOW at southeast corner of ash basin. Jacob's
S-04 34.589755 -78.966327 Swamp and C;Sw N/A Seep N/A Seep
Area repaired;seep eliminated. Dispositioned Dispositioned
the Lumber
River
*Location previously investigated as a seep. Monitoring has not indicated the presence of coal combustion residuals.
**Seep dispositioned via repair and/or non-flowing condition to potentially reach WOTUS,or other,as noted.
Monitoring shall be conducted at the approximate locations indicated on the attached site map.
All monitoring shall be conducted per the requirements found in Attachment B of this Order.

Attachment A
S19-006
Duke Energy Progress, LLC—Weatherspoon Steam Station, p. 4
Seep ID Approximate Location Receiving
Coordinates Description Receiving Interim Action
Number p WaterbodyWaterbody SOC Monitoring
Latitude Longitude Classification Levels
Monitoring location;not a seep.Small
channel near southeast corner of ash basin
near toe of dike.Location receives flow from UT to Monitoring at
Jacob's location S-05,
S-05** 34.589871 -78.96588 upstream locations S-02 and S-03.All flow at Swamp and C;Sw prior to joining Arsenic 500 µ/L
the location has been diverted from flowing Cadmium 10 µg/L
to Jacob's Swamp to now join engineered the Lumber other flows at
flow near S-15.Combined flows go to River S 15.
cooling pond.
Flow to ditch beyond north side of ash basin. UT to the —
S-06* 34.593088 -78.973552 Flows west toward S-07 and S-08.From Lumber C;Sw N/A—Seep N/A—Seep
sampling—No CCR impacts. River Dispositioned Dispositioned
UT to the
36"stormwater pipe,west former power Co ;Sw N/A—Seep N/A—Seep
S-07* 34.588211 -78.977747 Lumber
plant site. From sampling—No CCR impacts. Dispositioned Dispositioned
River
UT to the
S 08* 34.588199 78 97773 36"stormwater pipe,west of former pow ,r Lumber C;Sw N/A—Seep N/A—Seep
plant site. From sampling—No CCR impacts. Dispositioned Dispositioned
River
Monitoring location;not a seep. Drainage Site
ditch between dike wall and railroad track... drainage Monitoring at
S 09** 34.590244 -78.973407 Receives flow from S-01 upstream,and ditch system established Duke
flows toward S-16 downstream before flowing to C;Sw Energy S-16 See S-16
entering wetland complex and discharge to cooling monitoring site
cooling pond. pond
Seep located at the toe of the dike face on
the west side of the ash basin. Flow Collection N/A—Seep
conveyed via ditch to engineered channel ditch N/A—Not a contribution
flowing to Classified analyzed in N/A—Not a
S-10 34.589208 -78.971123 collecting toe drain discharges.All flow Classified Surface
conveyed to cooling pond.This non- NPDES Surface NPDES Permit
permit Water monitoring at Water
constructed seep flows to a portion of an
NPDES wastewater treatment system. outfall 001 Outfall 001
*Location previously investigated as a seep. Monitoring has not indicated the presence of coal combustion residuals.
**Seepdispositioned via repair and/
or non-flowing condition to
g potentiallyreach WOTUS, or other, as noted.
Monitoringshall be conducted at the
e approximate locations
s indicated on the attached site map.
All monitoring shall be conducted per the requirements found in Attachment B of this Order.

Attachment A
•
S19-006
Duke Energy Progress, LLC—Weatherspoon Steam Station, p. 5
Approximate Location
Receiving
Seep ID Receiving
Coordinates Description Waterbody SOC Monitoring Interim Action
Number Latitude Longitude Waterbody Levels
Classification
Monitoring location;not a seep.Sampling Effluent N/A—Seep
site at end of culvert under road paralleling channel N/A—Not a contribution
:■ south side of ash basin.Collects flows from flowingto Classified analyzed in NM—Not a
S-15 34.58924 -78.966433 Classified Surface
5-02,S-03,S-05,5-10 and toe drain NPDES Surface NPDES Permit
discharges.Combined flows are conveyed permit Water monitoring at Water
via engineered channel to cooling pond. outfall 001 Outfall 001
Monitoring location;not a seep. Narrow Site
ditch downstream of locations S-01 and S-09 drainage Monitoring at
S 16** 34.587238 -78.969535 conveying flow to coolingditch system established Duke Arsenic 15 ug/L
Y g pond. Location is flowingto C;Sw g/
upstream of where ditch enters wetland Energy S 16 Mercury 0.02 ug/L
complex. cooling monitoring site
pond
Culvert through berm,west of formerpower UT to the
S-18* 34.587809 -78.978069 Lumber C;Sw N/A—Seep N/A—Seep
plant site. From sampling—No CCR impacts. Dispositioned Dispositioned
River
Culvert through berm,west of former power UT to the N
;Sw /A—Seep N/A—Seep
S-22* 34.58781 -78.978079 Lumber C
plant site. From sampling—No CCR impacts. Dispositioned Dispositioned
River
Small seep at toe of ash basin south side Effluent N/A—Seep
dam.Flows to engineered channel collecting channel N/A—Not a contribution
S-23 34.589457 -78.966748
toe drain discharges.All flow conveyed to flowing to Classified analyzed in N/A—Not a
cooling pond.This non-constructed seep NPDES Surface NPDES Permit Classified Surface
flows to a portion of an NPDES wastewater permit Water monitoring at Water
treatment system. outfall 001 Outfall 001
Small seep at toe of ash basin south side Effluent N/A—Seep
dam. Flows to engineered channel collecting channel N/A—Not a contribution
toe drain discharges.All flow conveyed to flowing to Classified analyzed in N/A—Not a
S-24 34.5882 -78.9687 Classified Surface
cooling pond.This non-constructed seep NPDES Surface NPDES Permit
flows to a portion of an NPDES wastewater permit Water monitoring at Water
treatment system. outfall 001 Outfall 001
*Location previously investigated as a seep. Monitoring has not indicated the presence of coal combustion residuals.
**Seep dispositioned via repair and/or non-flowing condition to potentially reach WOTUS, or other, as noted.
Monitoring shall be conducted at the approximate locations indicated on the attached site map.
All monitoring shall be conducted per the requirements found in Attachment B of this Order.

.
W. H. Weatherspoon Plant — Water Quality Monitoring
-44P
4. 14 \4 1
4 i le ,,,,
he
Ash Basin
t4.4‘'`,, . \
41/41,—. t
r
F ,
t It
it'
Natimit ,
:'' ' Cooling
Pond
Instream Monitoring at S-05 & S-16 Locations

•
SOC S19-006
Duke Energy Progress, LLC—W. H. Weatherspoon Plant
Attachment B
Monitoring Requirements
The following represents the parameters to be analyzed and reported at all monitoring locations
designated within this Special Order.
Parameter Reporting Units Monitoring
Frequency
TSS mg/L Annually
Oil and Grease mg/L Annually
pH Standard Units(s. u.) Quarterly
Fluoride pg/L Quarterly
Total Mercury ng/L Quarterly
Total Barium pg/L Quarterly
Total Zinc pg/L Quarterly
Total Arsenic pg/L Quarterly
Total Boron pg/L Quarterly
Total Cadmium pg/L Quarterly
Total Chromium pg/L Quarterly
Total Copper pg/L Quarterly
Total Thallium pg/L Quarterly
Total Lead pg/L Quarterly
Total Nickel pg/L Quarterly
Total Selenium pg/L Quarterly
Nitrate/Nitrite as N mg/L Quarterly
Bromides mg/L Quarterly
Sulfates mg/L Quarterly
Chlorides mglL Quarterly
TDS mg/L Quarterly
Total Hardness mg/L Quarterly
Temperature ° C Quarterly
Conductivity, pmho/cm pmho/cm Quarterly
Analyses of all monitoring conducted per the terms of this SOC shall conform to the requirements of 15A
NCAC 2B .0505(e)(4)and(5); i.e., standard methods and certified laboratories shall be used.

•
Seep Management Plan Amendment to the Corrective Action Plan
W.H.Weatherspoon Power Plant—Duke Energy Progress, LLC
Lumberton, North Carolina
APPENDIX B
MANN KENDALL TREND TEST ANALYSIS,
AUGUST 2022
synTerra
Science & Engineering Consultants

. .
synTerra Science & Engineering Consultants
synterracorp.com
APPENDIX B
MANN-KENDALL TREND TEST ANALYSIS
W.H. WEATHERSPOON POWER PLANT
AUGUST 2022
PREPARED FOR
41N DUKE
ENERGY
PROGRESS
DUKE ENERGY PROGRESS,LLC

t r
Appendix B-Mann-Kendall Trend Test Analysis
W.H.Weatherspoon Power Plant, Duke Energy Progress, LLC
Lumberton, North Carolina
TABLE OF CONTENTS
SECTION PAGE
1.0 THE MANN-KENDALL TREND TEST 1-1
2.0 TIME VERSUS CONCENTRATION PLOTS 2-1
3.0 MANN-KENDALL TREND TEST RESULTS 3-1
LIST OF FIGURES
Figure 1 Time versus Total Arsenic Concentration
Figure 2 Time versus Total Barium Concentration
Figure 3 Time versus Total Boron Concentration
Figure 4 Time versus Bromide Concentration
Figure 5 Time verses Total Cadmium Concentration
Figure 6 Time versus Chloride Concentration
Figure 7 Time versus Total Chromium Concentration
Figure 8 Time versus Specific Conductance
Figure 9 Time versus Total Copper Concentration
Figure 10 Time versus Fluoride Concentration
Figure 11 Time versus Hardness
Figure 12 Time versus Total Lead Concentration
Figure 13 Time versus Total Mercury Concentration
Figure 14 Time versus Total Nickel Concentration
Figure 15 Time versus Nitrate + Nitrite Concentration
Figure 16 Time versus Oil and Grease
Figure 17 Time versus pH
Figure 18 Time versus Total Selenium Concentration
Figure 19 Time versus Total Sulfate Concentration
Figure 20 Time versus Total Dissolved Solids Concentration
Figure 21 Time versus Temperature
Figure 22 Time versus Total Thallium Concentration
Figure 23 Time versus Total Suspended Solids Concentration
Figure 24 Time versus Total Zinc Concentration
Figure 25 Time versus Dissolved Metals Concentration
LIST OF TABLES
Table 1 Sampling Locations and Constituents Included in Concentration over Time Plots
Table 2 Mann-Kendall Trend Analysis Results
August 2022 Page i
Project:00.0066.17

Appendix B-Mann-Kendall Trend Test Analysis
W.H.Weatherspoon Power Plant, Duke Energy Progress, LLC
Lumberton, North Carolina
1.0 THE MANN-KENDALL TREND TEST
Mann-Kendall trend tests were performed on available seep data associated with the ash basin
at the W.H. Weatherspoon Power Plant.The Mann-Kendall trend test evaluates data over time
for monotonic trends, where monotonic indicates a trend that is solely increasing or
decreasing. Mann-Kendall is a useful trend test in that it is non-parametric and does not require
normal distribution of data.
To perform the Mann-Kendall trend test, data were processed as follows:
• Non-detects greater than regulatory values were removed. If a constituent does not
have a regulatory limit and there are multiple reporting limits, only the lowest reporting
limit was retained.
• Detects that were less than the reporting limit were treated at non-detects.
• Samples with pH greater than 10 standard units were removed.
Next, the data must meet the following requirements for a Mann-Kendall trend test to be
applicable:
• There must be at least four detect measurements.
• Non-detects must make up less than or equal to 50 percent of measurements.
In a Mann-Kendall trend test, each value is compared to the proceeding values to calculate
whether the value has increased, decreased, or stayed the same over time.These comparisons
are recorded as simply 1 (increasing), -1 (decreasing), or 0 (stayed the same). These
comparisons give an S value, where S indicates the type of trend. A negative S value indicates a
decreasing trend, and a positive S value indicates an increasing trend. Whether or not these
trends are statistically significant is dependent on the two-sided p value. A p value ranges from
0 to 1 and indicates whether the results are due to chance or the results are statistically
significant. Greater p values indicate a trend is not statistically significant, and a p value less
than 0.1 indicates a statistically significant trend.
All Mann-Kendall trend tests are performed in the program RStudio using the "Kendall"
package.
August 2022 Page 1-1
Project:00.0066.17

Appendix B-Mann-Kendall Trend Test Analysis
W.H.Weatherspoon Power Plant, Duke Energy Progress, LLC
Lumberton, North Carolina
2.0 TIME VERSUS CONCENTRATION PLOTS
Plots of concentration over time provide a visual representation of possible trends in the data.
Time versus concentration plots are presented as Figures 1 through 25. Plots are grouped by
constituent, and within the figure, a plot of concentration over time is displayed for each
location that has data for that constituent. Locations and constituents included in these plots
are presented in Table 1.
Trends from the Mann-Kendall tests are displayed on plots with colored borders representing
trend conclusions. Blue indicates no trend was present, green indicates a decreasing trend, gold
indicates an increasing trend, and no color indicates the constituent-location pair cannot be
analyzed for trends due to a lack of detect measurements. Detect measurements are shown as
a black point, and non-detect measurements are shown as an open circle.
August 2022 Page 2-1
Project:00.0066.17

Appendix B-Mann-Kendall Trend Test Analysis
W.H.Weatherspoon Power Plant, Duke Energy Progress, LLC
Lumberton, North Carolina
TABLE 1
SAMPLING LOCATIONS AND CONSTITUENTS INCLUDED IN PLOTS
OF CONCENTRATIONS OVER TIME
Sampling Locations Constituents
S-05 Total and Dissolved Arsenic
S-16 Total Barium
Total Boron
Bromide
Total and Dissolved Cadmium
Chloride
Total and Dissolved Chromium
Total and Dissolved Copper
Fluoride
Hardness
Total and Dissolved Lead
Total Mercury
Total and Dissolved Nickel
Nitrate+Nitrite
Oil and Grease
pH
Total Selenium
Specific Conductance
Temperature
Total Thallium
Total Dissolved Solids
Total Sulfate
Total Suspended Solids
Total and Dissolved Zinc
August 2022 Page 2-2
Project:00.0066.17

Appendix B-Mann-Kendall Trend Test Analysis
W.H.Weatherspoon Power Plant, Duke Energy Progress, LLC
Lumberton, North Carolina
3.0 MANN-KENDALL TREND TEST RESULTS
Results of the Mann-Kendall trend tests are presented in Table 2. Mann-Kendall trend tests
were conducted for data pertaining to the two dispositioned seeps associated with the ash
basin that are utilized for water quality monitoring.Trend analyses were completed for 48
location-constituent pairs using available seep data that were collected between 2014 and
2022. For the other occurrences where trend analysis could not be performed, either there are
less than four detects, or the number of non-detects is greater than the number of detects.The
average percentage of non-detects for all constituent-location pairs included in the Mann-
Kendall trend test is 35 percent.
Locations not displayed in Table 2 are excluded due to having less than the minimum number
of samples required to run the "Kendall" package in RStudio. Location-constituent pairs with
less than four detects are included in Table 2 but cannot be analyzed for trends based on the
criteria in Section 1.0.
Out of the 55 constituent-location pairs that have trend conclusions, 10 are associated with the
following field parameters: pH, specific conductance, temperature, total dissolved solids, and
total suspended solids. Trends for these field parameters were evaluated for information but
are not included in percentages below. Of the 45 chemical constituent-location pairs that have
trend conclusions, 47 percent of constituent concentrations are stable or have statistically
significant decreasing trends (21 out of 45 constituent location pairs), 51 percent (24 out of 45)
of trends could not be analyzed due to greater than 50 percent non detects, and 2 percent (1
out of 45) of constituent concentrations have statistically significant increasing trends.
Overall, the results of the Mann-Kendall trend tests indicate a system that is geochemically
stable, with the majority of constituent concentrations remaining stable over time.
August 2022 Page 3-1
Project:00.0066.17

APPENDIX B-TABLE 2
MANN-KENDALL TREND ANALYSIS RESULTS
SEEP MANAGEMENT PLAN AMENDEMENT TO THE CORRECTIVE ACTION PLAN '
W.H.WEATHERSPOON POWER PLANT
DUKE ENERGY PROGRESS,LLC,LUMBERTON,NC
Number Percent Is Trend Two-Sided
Well ID Analyze S Value Trend Conclusion
of Samples Non-Detects Detects Non-Detects Analysis Applicable? P Value
S-16 pH 21 0 21 0 Yes 3.98E-01 - Stable,no significant trend
S-5 pH 12 0 12 0 Yes 3.04E-01 - Stable,no significant trend
5-16 Temperature 21 0 21 0 Yes 7.62E-01 - Stable,no significant trend
5-5 Temperature 12 0 12 0 Yes 7.32E-01 - Stable,no significant trend
S-16 Specific Conductance 21 0 21 0 Yes 3.72E-02 -70 Statistically significant decreasing trend
S-5 Specific Conductance 12 0 12 0 Yes 2.06E-04 -55 Statistically significant decreasing trend
5-16 Total Suspended Solids 10 2 8 20 Yes 6.83E-03 -31 Statistically significant decreasing trend
5-5 Total Suspended Solids 3 1 2 33 No - - Cannot analyze for trends
5-16 Boron 21 0 21 0 Yes 3.70E-02 -70 Statistically significant decreasing trend
S-5 Boron 12 0 12 0 Yes 5.89E-04 -51 Statistically significant decreasing trend
S-16 Chloride 21 0 21 0 Yes 1.52E-05 -144 Statistically significant decreasing trend
S-5 Chloride 12 0 12 0 Yes 3.51E-04 -53 Statistically significant decreasing trend
S-16 Sulfate 21 0 21 0 Yes 3.20E-02 -72 Statistically significant decreasing trend
S-5 Sulfate 12 0 12 0 Yes 5.43E-02 -29 Statistically significant decreasing trend
S-16 Total Dissolved Solids 21 0 21 0 Yes 4.97E-02 -66 Statistically significant decreasing trend
5-S Total Dissolved Solids 12 0 12 0 Yes 2.06E-04 -55 Statistically significant decreasing trend
S-16 Arsenic 21 0 21 0 Yes 1.74E-01 - Stable,no significant trend
S-5 Arsenic 12 0 12 0 Yes 7.32E-01 - Stable,no significant trend
5-16 Barium 21 0 21 0 Yes 6.51E-01 - Stable,no significant trend
5-5 Barium 12 0 12 0 Yes 8.91E-01 - Stable,no significant trend
S-16 Cadmium 15 15 0 100 No - - Cannot analyze for trends
S-5 Cadmium 7 6 1 86 No - - Cannot analyze for trends
S-16 Chromium 21 20 1 95 No - - Cannot analyze for trends
5-5 Chromium 12 12 0 100 No - - Cannot analyze for trends
S-16 Copper 16 15 1 94 No - - Cannot analyze for trends
S-5 Copper 12 9 3 75 No - - Cannot analyze for trends
S-16 Lead 15 8 7 53 No - - Cannot analyze for trends
S-5 Lead 6 5 1 83 No - - Cannot analyze for trends
5-16 Mercury 20 0 20 0 Yes 1.00E+00 - Stable,no significant trend
S-5 Mercury 11 3 8 27 Yes 5.82E-01 - Stable,no significant trend
S-16 Nickel 21 0 21 0 Yes 7.63E-05 -132 Statistically significant decreasing trend
S-5 Nickel 12 0 12 0 Yes 2.88E-05 -62 Statistically significant decreasing trend
S-16 Nitrate+Nitrite 19 0 19 0 Yes 3.97E-03 83 Statistically significant increasingtrend
5-5 Nitrate+Nitrite 11 1 10 9 Yes 2.73E-01 - Stable,no significant trend
5-16 Selenium 21 21 0 100 No - - Cannot analyze for trends
5-5 Selenium 12 10 2 83 No - - Cannot analyze for trends
-
5-16 Thallium 21 20 1 95 No - - Cannot analyze for trends
S-5 Thallium 12 11 1 92 No - - Cannot analyze for trends
5-16 Zinc 21 12 9 57 No - - Cannot analyze for trends
S-5 Zinc 12 10 2 83 No - - Cannot analyze for trends
S-16 Bromide 13 3 10 23 Yes 8.53E-01 - Stable,no significant trend
5-5 Bromide 6 0 6 0 Yes 6.03E-02 -11 Statistically significant decreasing trend
Page 1 of 2

APPENDIX B-TABLE 2
MANN-KENDALL TREND ANALYSIS RESULTS
SEEP MANAGEMENT PLAN AMENDEMENT TO THE CORRECTIVE ACTION PLAN
W.H.WEATHERSPOON POWER PLANT
DUKE ENERGY PROGRESS,LLC,LUMBERTON,NC
Number Percent Is Trend Two-Sided
Well ID Analyte S Value Trend Conclusion
of Samples Non-Detects Detects Non-Detects Analysis Applicable? P Value
5-16 Fluoride 113 16 0 100 No - - Cannot analyze for trends
S-5 Fluoride 1 2 2 s0 No - - Cannot analyze for trends
S-16 Hardness 19 0 19 0 Yes 5.29E-01 - Stable,no significant trend
5-5 Hardness !0 0 10 0 Yes 1.28E-03 -37 Statistically significant decreasing trend
S-16 Oil and grease 11 11 0 100 No - - Cannot analyze for trends
-
5-5 Oil and grease 7 7 0 100 No - - Cannot analyze for trends
S-16 Dissolved Arsenic 10 3 7 30 Yes 4.66E-01 - Stable,no significant trend
S-16 Dissolved Cadmium 10 10 0 100 No - - Cannot Analyze for Trends
S-16 Dissolved Chromium 10 10 0 l00 No - - Cannot Analyze for Trends
S-16 Dissolved Copper 5 3 2 60 No - - Cannot Analyze for Trends
S-16 Dissolved Lead 10 10 0 100 No - - Cannot Analyze for Trends
S-16 Dissolved Nickel 10 0 10 0 Yes 4.74E-01 - Stable,no significant trend
-
S-16 Dissolved Zinc 10 8 2 80 No - - Cannot Analyze for Trends
Notes: Prepared by:RSB Checked by:EMY
Detection limits were adjusted in accordance with USEPA guidelines
Page 2 of 2

Appendix B-Mann-Kendall Trend Test Analysis
W.H.Weatherspoon Power Plant, Duke Energy Progress, LLC
Lumberton, North Carolina
FIGURES
synTerra
Science & Engineering Consultants

S-5 S-16
75 75 Ix
J
01 [1b
50 !50
o .4
A 15
UU Space not used.
25 •4 25•
v112,
0, 0.
,,, :, u.Date „ .. .A a m Date G o - ,.
Space not used. Space not used. Space not used.
LEGEND NOTES elfal DUKE
DRAWN BY:R.BADUM DATE]DSr2022
-0-Non-detect • Data presented on concentration plots includes all sampling programs. ENERGY REVISED BY: DATE: FIGURE 1
Detect • Data presented may include lab-qualified results.Non-detect analytical results are plotted at the
PROGRESS CHECKED BY:E.YURKOVICH DATE: TIME VERSUS TOTAL ARSENIC CONCENTRATION
corresponding reporting limit. SEEP MANAGEMENT PLAN
• Time vs total arsenic plot for all locations with available data.Trends are denoted by the box color,if APPROVED BY:I.WYLIE DATE Bn9/2022 APPENDIX B
- there is no color the data could not be analyzed for trends
Stable,no trends MANN-KENDALL TREND ANALYSIS
• Hg/L-micrograms per liter PROJECT MANAGER,J.WYLIE-Statistically Significant Decreasing Trend �^� W.H.WEATHERSPOON POWER PLANT
-Statistically Significant Increasing Trend �r�Ter1[J LUMBERTON,NORTH CAROLINA
No Color-Cannot Analyze for Trends www.synterracorp.com

S-5 S-16
200 200 -
tso a tso
3 3
E
0
mtoo gtoo
o Space not used.
I
UE 50 m 50
0 0 aa
Date Date
Space not used. Space not used. Space not used.
LEGEND DUKE
NOTES DRAWN BY:R.BADUM DATE:]/15/2012
- Non-detect • Data presented on concentration plots includes all sampling programs. ENERGY REVISED BY: DATE: FIGURE 2
- Detect • Datapresented mayinclude lab-qualified results.Non-detect analytical results areplotted at the PROGRESS CHECKED BY:E.YURKOVICH DATE: TIME VERSUS TOTAL BARIUM CONCENTRATION
inc qua SEEP MANAGEMENT PLAN
corresponding reporting limit.
II
• Time vs barium plot for all locations with available data.Trends are denoted by the box color,if
APPROVED BY:J.WYLIE DATE:Bn8/2022 APPENDIX B
-Stable,notrends there is totalno br the data could not bens with
rends PROJECT MANAGER:J.WYLIE MANN-KENDALL TREND ANALYSIS
-Statistically Significant Decreasing Trend • pgIl-micrograms per liter ' W.H.WEATHERSPOON POWER PLANT
-Statistically Significant Increasing Trend LUMBERTON,NORTH CAROLINA
No Color-Cannot Analyze for Trends synTerra www.synterracorp
.com

S-5 S-16
2500• 2500 w.
2000 2000
11:::
c
Space not used.
loon woo
o a
o
In m
500. 500
0 0
1
•
Date E..,Date
Space not used. Space not used. Space not used.
LEGEND NOTESeta* DUKE
DRAWN BY:R.BMUM DATE:7/15I2022
-C/-Non-detect • Data presented on concentration plots includes all sampling programs. ' ENERGY REVISED BY: DATE: FIGURE 3
—0—Detect • Data presented may include lab-qualified results.Non-detect analytical results are plotted at the PROGRESS CHECKED BY:E.YURKOVICH DATE:]ItB12Uz2 TIME VERSUS TOTAL BORON CONCENTRATION
SEEP MANAGEMENT PLAN
corresponding reporting limit.
• Time vs total boron plot for all locations with available data.Trends are denoted by the box color,if APPROVED BY:J.WYLIE DATE:B/19/2022 APPENDIX B
-Stable,no trends there is no color the data could not be analyzed for trends PROJECT MANAGER:J.WYLIE MANN-KENDALL TREND ANALYSIS
-Statistically Significant Decreasing Trend • pg/L-micrograms per liter ' W.H.WEATHERSPOON POWER PLANT
-Statistically Significant Increasing Trend LUMBERTON,NORTH CAROLINA
No Color-Cannot Analyze for Trends synTerra www.synterrecorp.com

S-5 S-16
9D0 800 --..
'''''''.1\
J
9 cm
t 400 \ ....
c 400
.4 4
5 m
c
S c
U
0 u
v 0 Space not used.
o
200 200
E L
Q o \\\v/\>iv./\ .
co co
0 0
o Date m V m Date
•
•
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LEGEND NOTES (�DUKE DRAWN BY:R.BADUM DATE:T/15/2022
-0-Non-detect • Data presented on concentration plots includes an sampling programs. ENERGY REVISED BY: DATE: FIGURE 4
AI-Detect • Data presented may include lab- lifted results.Non-detect analytical are plotted at TIME VERSUS BROMIDE CONCENTRATION
qua lytica PROGRESS CHECKED BY:E.YURKOVICH DATE:2/18/2022
corresponding reporting limb. SEEP MANAGEMENT PLAN
• Time vs bromide plot for all locations with available data.Trends are denoted by the box color,if there /// APPROVED BY:J.WYLIE DATE:B/1W2022 APPENDIX B
Stable,no trends is no color the data could not be analyzed for trends MANN-KE NDALL TREND ANALYSIS
PROJECT MANAGER:J.WYLIE
-Statistically Significant Decreasing Trend . Ngil-micrograms per liter ' W.H.WEATHERSPOON POWER PLANT
-Statistically Significant Increasing Trend LUMBERTON,NORTH CAROLINA
No Color-Cannot Analyze for Trends synTerra www.synterracorp.com

S-5 S-16
J 4. J.1
o, pl
.1
C
p o
b 3 m 3,
8
`o o Space not used.
U z U 2
E £
E E
m m
U t. U 1• 0 00 O O
p.
.:, .,, _ - -
Date Date
Space not used. Space not used. Space not used.
LEGEND .s DUKE NOTES r` DRAWN BY:R.WHIM DATE:'//t 512p12
- Non-detect • Data presented on concentration plots includes all sampling programs. IC'ENERGY REVISED BY: DATE: FIGURE 5
- Detect TIME VERSUS TOTAL CADMIUM CONCENTRATION
• Data presented may include lab-qualified results.Non-detect analytical results are plotted at the PROGRESS CHECKED BY:E.YURKOVICH DATE:UM/2On SEEP MANAGEMENT PLAN
corresponding reporting limit.
Time total cadmium plot for all locations with available data.Trends are denoted by the box color,if APPROVED BY:I.WYLIE DATE:I/19/2oz2 APPENDIX B
Stablei no yrSigns there Is no color the data could not be analyzed for trends MANN-KENDALL TREND ANALYSIS
Statistically Significant Decreasing Trend y PROJECT MANAGER:J.WVLIE W.H.WEATHERSPOON POWER PLANT
•
• pg/t-micrograms per liter
P-Statistically Significant Increasing Trend LUMBERTON,NORTH CAROLINA
No Color-Cannot Analyze for Trends synTerra www.synterrecorp.com

S-5 S-16
45— 45
t g
30 30
o
aJ A
C C
a C
s . Space not used.
a 15 0 15.
0 _
U U
0
,. �, ' Date N a m Date e
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LEGEND DUKE NOTES l/ DRAWN BY:R.BADUM DATE 7I1 L2022 •
- Non-Detect • Data presented on concentration plots includes all sampling programs. ENERGY REVISED BY: DATE: FIGURE 6
+Detect TIME VERSUS CHLORIDE CONCENTRATION
— • Data presented may include lab-qualified results.Non-detect analytical results are plotted at the PROGRESS CHECKED BY:E.YURKOVIGH DATE:2n11/2022 SEEP MANAGEMENT PLAN
corresponding reporting limit.
• Tinoe vs chloride plot for all locations with available data.Trends are denoted by the box color,if there APPROVED BY:J.WVLIE DATE:analzo22 APPENDIX B
II-Stable,no trends color the data could not be analyzed for trends MANN-KENDALL TREND ANALYSIS
-Statistically Significant Decreasing Trend PROJECT MANAGER:J.WYLIE
-StatisticallSignificant IncreasingTrend mg/L-milligrams per liter W.H.WEATHERSPOON POWER PLANT
g synTerra LUMBERTON,NORTH CAROLINA
No Color-Cannot Analyze for Trends
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S-5 S-16
J J
m tT
a - 0 2.
6
y yCy
U
C
I
g Space not used.
,• 0 0 0 0 0 0 0 00000 E t.
G o
L
U U
0 0
Date ., . Date ...
Space not used. Space not used. Space not used.
LEGEND NOTES eta.,DUKE DRAWN BY:R.BADUM DATE:7/ts/z02z
- NOD-detect • Data presented on concentration plots Indudes all sampling programs. ' ENERGY REVISED BY: DATE: FIGURE 7
- Detect TIME VERSUS TOTAL CHROMIUM CONCENTRATION
• Data presented may include lab-qualified results.Non-detect analytical results are plotted at the PROGRESS CHECNED BYTE.YUREOVICH DATE:7/la/ton
corresponding reporting limit. SEEP MANAGEMENT PLAN
I
• Time vs total chromium plot for all locations with available data.Trends are denoted by the box color, APPROVED BYJ.WYLIE DATE ana/2022 APPENDIX B
-Stable,no trends
if there is no color the data could not be analyzed for trends PROJECT MANAGER:J.WYLIE MANN-KENDALL TREND ANALYSIS
-Statistically Significant Decreasing Trend • pg/t-micrograms per liter W.H.WEATHERSPOON POWER PLANT
-Statistically Significant Increasing Trend synTerra LUMBERTON,NORTH CAROLINA
No Color-Can not Analyze for Trends www.synterracorp.com

S-5 S-16 -
5000 5000
t 4000 1::
c
m m
a
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'Cl 2000 c 2000
U U
t
u 1000
cna 1000
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0 0
Date m Date
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LEGEND •�DUKE
NOTE (` DRAWN BY.R.BADUM DATE:1/15/2022
- Non-detect • Data presented on concentration plots includes all sampling programs. C ENERGY REVISED BY: DATE: FIGURE 8
- Detect TIME VERSUS SPECIFIC CONDUCTANCE
• Data presented may include lab-qualified results.Non-detect analytical results are plotted at the PROGRESS CHECKED BY:E.YURKOVCH DATE:7/1B/2022 SEEP MANAGEMENT PLAN
corresponding reporting limit.
Time vs specific conductance plot for all locations with available data.Trends are denoted by the box APPROVED BY:J.WYLIE DATE:B11912022 APPENDIX B
Stable,no trendsll
0MANN-KENDALL TREND ANALYSIS
color,if there is no color the data could not be analyzed for trends PROTECT MANAGER:J.WriIE
•
-Statistically Significant Decreasing Trend • Hmhos/cm-micromhos per centimeter W.H.WEATHERSPOON POWER PLANT
-Statistically Significant Increasing Trend LUMBERTON,NORTH CAROLINA
No Color-Cannot Analyze for Trends synTerra wwwsynterracorp.com

S-5 S-16
5
1, 1'
J J
.i C
3• p 3
c ct
u
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0
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U 2 U 2'
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8' n
a O
U U
1 t.
n 0
Date .. Date
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O- DUKE f10TE5 DRAWN BY:P.BADDM DATE:)n512022
Non-detect • Data presented on concentration lots includes all sampling �C ENERGY FIGURE 9
�- P programs. REVISED BY: DATE
TIME VERSUS TOTAL COPPER CONCENTRATION
• Data presented may include lab-qualified results.Non-detect analytical results are plotted at the PROGRESS CHECKED BY:E.WRKOVICH DATE:7n8l2022 SEEP MANAGEMENT PLAN
corresponding total
ng reporting limit. APPROVED BY:J.WYLIE DATE:811012022 APPENDIX B
- • Time vs total copper plot for all locations with available data.Trends are denoted by the box color,if
Stable,no trends MANN-KENDALL TREND ANALYSIS
there is no color the data could not be analyzed for trends PROJECT MANAGER:J.WYLIE
-Statistically Significant Decreasing Trend • P0�t-micro ' W.H.WEATHERSPOON POWER PLANT
grams per liter
-Statistically Significant Increasing Trend LUMBERTON,NORTH CAROLINA
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.com

S-5 S-16
: —I
E E
c
0 a
m m
c
0 o Space not used.
a, v
a
`o 0
t if
•
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•
LEGEND DUKE
NOTES DRAWN BY:R.BADUM DATE:111512022
Non-detect ' ENERGY FIGURE 10
—ID—Detect • Data presented on concentration lots includes all sampling REVISED eV. DATE:
p p gprograms. PROGRESS CHECKED Br E.VURKOVICH DATE W18/2022 TIME VERSUS FLUORIDE CONCENTRATION
• Data presented may include lab-qualified results.Non-detect analytical results are plotted at the SEEP MANAGEMENT PLAN
I
corresponding reporting limit. / APPROVED MANAGER:
WYLIE DATE'.BI19/2022 APPENDIX B
-Sable,no trends • Time vs fluoride plot for all locations with available data.Trends are denoted by the box color,if there / MANN-KENDALL TREND ANALYSIS
`I PROJECT MANAGER:LI WYLIE
-Statistically Significant Decreasing Trend color the data could not be analy2ed for trends W.H.WEATHERSPOON POWER PLANT
-Statistically Significant Increasing Trend mg/L-milligramsper liter LUMBERTON,NORTH CAROLINA
No Color-Cannot Analyze for Trends synTerra www.synterracorp
.com

r
S-5 S-16
400 400
J
E 300 0 300
E
o B
S
1 :oil
c 1 :::
Space not used.
o. o •
Date m m Date
Space not used. Space not used. Space not used.
LE END NOTES tke.,DUKE
DRAWN BY:R.BADUM GATE:7n5/2022
Non-detect • Data presented on concentration plots indudes all sampling programs. ENERGY REVISED BY: DATE: FIGURE 11
Detect • Data presented may include lab-qualified results.Non-detect analytical results are plotted at the TIME VERSUS HARDNESS
corresponding reporting limit. PROGRESS CHECKED BY:E.VURKOVICH DOTE:]nalzozz SEEP MANAGEMENT PLAN
• Time vs hardness plot for all locations with available data.Trends are denoted by the box color,if there / PROJECT MANAGER:J.WYLIE
APPROVED BY:J.WYLIE DATE:Wt9/2022 APPENDIX B
111 Stable,no trends no color the data could not be analyzed for trends MANN-KENDALL TREND ANALYSIS
-Statistically Significant Decreasing Trend mg/L-milligrams per liter ' W.H.WEATHERSPOON POWER PLANT
-Statistically Significant Increasing Trend LUMBERTON,NORTH CAROLINA
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.com t

S-5 S-16
20 -
1 5 ^1.5•
o am
co 0
f
c 10 L 1.0 0 oo 0 0
Space not used.
tj U
m
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0 0 0.0
CO Date m Date +
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LE END DUKE
NOTES DRAWN BY:R.BADUM DATE 7/15/2022
— —net detect • Datapresented on concentration includes all samplingprograms. ENERGY REVISED BY: DATE: FIGURE 12
—�—Detect plots Pr H TIME VERSUS TOTAL LEAD CONCENTRATION
• Data presented may include lab-qualified results.Non-detect analytical results are plotted at the PROGRESS CHECKED BY:E.YURKOVICH DATE)/18R022 SEEP MANAGEMENT PLAN
corresponding reporting limit.
I
• Time vs total lead plot for all locations with available data.Trends are denoted by the box color,It APPROVED BY:J.WYLIE DATE:8/19/2022 APPENDIX B
-Stable,no trSigi there is no color the data could not be analyzed for trends• tIg/L-micrograms per liter PROJECT MANAGER:J. MANN-KENDALL TREND ANALYSIS
-Statistically Significant Decreasing Trend .WYLIE W.H.WEATHERSPOON POWER PLANT
-Statistically Analyze
Increasing Trend LUMBERTON,NORTH CAROLINA
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S-5 S-16
2e°00 2e+00 '
- 2e-01ea a 2e-01
3
g 4
8 2e-02. 8 2e-02
0 o Space not used.
U U
✓ r
'e g
l' 2e-03 2e-03
2e-04. 2e-04
m Data ' +Date
Space not used. Space not used. - Space not used.
LEGEND NOTES DUKE(`` DRAWN BOB: .BADIIM DATE:1/15/2021
- Non-detect • Data presented on concentration plots includes all sampling programs. ENERGY REVISED DV: DATE: FIGURE 13
- Detect • Data presented may include lab-qualified results.Non-detect analytical results areplotted at the TIME VERSUS TOTAL MERCURY CONCENTRATION
PROGRESS CHECKED BY:E.YIIRKOVICH DATE:Ine/202Z SEEP MANAGEMENT PLAN
corresponding reporting limit.
I
• Time vs total mercury plot for all locations with available data.Trends are denoted by the boo color,if APPROVED BV:J.WYLIE DATE:WI Bl2022 APPENDIX B
-Stable,no trends there Is no color the data could not be analyzed for trends PROJECT NUNAGER:J.WYIIE MAN N-KENDALL TREND ANALYSIS
-Statistically Significant Decreasing Trend - nib micrograms per liter ' H.
-Statistically Significant Increasing Trend W UM ERTON,NORTH COAROLINA PLANT
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S-5 S-16
20 20
C
g 10
Space not used.
0 0
U U
d v
2 5. 2 5
p 0
m -
Date Date
Space not used. Space not used. Space not used.
LEGEND F�DUKE
NOTESDRAWN BY:R.BADUM DATE:]n 512a22
-O-Non-detect • Data presented on concentration plots includes all sampling programs. ENERGY REVISED BY: DATE: FIGURE 14
AI-Detect • Data presented may include lab-qualified results.Non-detect analytical results are plotted at the PROGRESS CHECKED BY:E.YURKOVICH DATE:]nermzz TIME VERSUS TOTAL NICKEL CONCENTRATION
corresponding reporting limit. SEEP MANAGEMENT PLAN
• Time vs total nickel plot for all locations with available data.Trends are denoted by the box color,if APPROVED BY:J.WYLIE DATE:Bn112022 APPENDIX B
Ill
- y s MANN-KENDALL TREND ANALYSIS
there is no color the data could not be analyzed for trends• PROJECT MANAGER:J.WYLIE
-StatisticallyStableino Siggnnificant Decreasing Trend
Si pg�t-micrograms per literW.H.WEATHERSPOON POWER PLANT
-Statistically Significant Increasing Trend LUMBERTON,NORTH CAROLINA
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S-5 S-16
0.5 0.51.
J J
0.4 0.4
co
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c
a o
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m 3
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do.2 do.2.
z z
m v
0.1 E 0.1.
Z Z
0.0 0 r, 0 IL 0 0 .0
Date a Oats
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LEGEND NOTES . REVISED-BY:
DATE:DUKE DRAWN BY:R.DATUM DATE:)/15/2022
-0-Non-deter[ `C ENERGY FIGURE 15
• Data presented on concentration plots includes all sampling programs.
Detect TIME VERSUS NITRATE+NITRITE CONCENTRATION
• Data presented may Include lab-qualified results.Non-detect analytical results are plotted at the PROGRESS CHECKED BY:E.WIRKOVICH DATE:7/18/2022 SEEP MANAGEMENT PLAN
corresponding Nitrate
reporting limit - APPROVED DV:J.WYLIE DATE 8I19/2022 APPENDIX B
- • Time vs Nitrate+Nitrite plot for all locations with available data.Trends are denoted by the box color,
Stable,s no trends MANN-KENDALL TREND ANALYSIS
I If there-milligrams
color the data n could not be analyzed for[rends PROJECT MANAGER:J.WYLIE-Statistically Significant Decreasing Trend • mg-N/L—milligramsnitrogen per liter r-� W.H.WEATHERSPOON POWER PLANT
-Statistically Significant Increasing Trend �r1Ter1 G LUMBERTONI NORTH CAROLINA
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S-5 S-16
6 F
11 0 O O O 0 0 0 J 0 0 O 0 0 O O O O 0
EEEd
c
o m J.
cyy U
5,
C C
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i
Lz z
0
O V
c c
tom
O O
e
.. Date Date
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LEGEND as DUKE
NOTES r` DRAWN BY:R.BADDM DATE:]OSI2022
I�-Non-detect • Data presented on concentration plots includes all sampling programs. ` ENERGY REVISED BY: DATE: FIGURE 16
+Detect TIME VERSUS OIL AND GREASE
• Data presented may include lab-qualified results.Non-detect analytical results are plotted at the PROGRESS CHECKED BY:E.YURKOVICH DATE:2n1/2022 SEEP MANAGEMENT PLAN
corresponding reporting limit.
• Time vs total oil and grease far all locations with available data.Trends are denoted by the boa color,if APPROVED BY:J.WYLIE DATE:,c1&2022 APPENDIX B
MANN-KENDALL TREND ANALYSIS
there Is no color the data could not be analyzed for trends PROJECT MANAGER:J.WYLIE
111
-StatisticallyStableinoyrSigns Significant Decreasing
Trend • mg/L-milligrams per liter ' W.H.WEATHERSPOON POWER PLANT
-Statistically Significant Increasing Trend S)/C'1TeRa LUMBERTON,NORTH CAROLINA
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12— 12.,= •,--..-. ..
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n I
c c
n 8. D 8•
V 9
v, e• a Space not used.
x x
n n
4• 4•
2+ 2 I
3
N Date c zA v m Date
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LEGEND NOTES r .e DUKE
` DRAWN BY:R.BADDM DATE 1I1512t122
Non-detect • Data presented on concentration plots includes all sampling programs. ` ENERGY REVISED BY: DATE: FIGURE S7
-�--Detect TIME VERSUS pH
• • Data presented may include lab-qualified results.Non-detect analytical results are plotted at the PROGRESS CHECKED BY:E.YURNOVICH DATE:7/18/2022 SEEP MANAGEMENT PLAN
corresponding reporting limit.
IIs no vs total pH plot for all locations with available data.Trends are denoted by the boo color,if there APPROVED ev:J.wvuE nunE:anw20n APPENDIX B
-Stable,no trends color the data could not be analyzed for trends 0MANN-KENDALL TREND ANALYSIS
•
-Statistically Significant Decreasing Trend y PROJECT MANAGER:J.WYLIE
-Statistically Significant Increasing Trend W.H.WEATHERSPOON POWER PLANT
LUMBERTO N,NORTH CAROLINA
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2.0 2.0
d 1.5. rn 1.5•
s s
s
3 to ! to
0 0 Space not used.
- o.s- + o.s
to
oo o.o•
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Date u, a m Date _.
Space not used. Space not used. Space not used.
•
LEGEND .DUKE DRAWN BY:R.BADUM DATE:7/15/2022
NOTES ENERGYIGURE 18
-O-Non-detect • Data presented on concentration plots includes all sampling programs. REVISED Be:BY: DATE:
-�lhtect • Data presented may include lab-qualified results.Non-detect analytical results are plotted at the PROGRESS CHECKED BY:E.YURKOVICH DATE:7/18/2021
TIME VERSUS TOTAL SELENIUM CONCENTRATION
corresponding reporting limit. SEEP MANAGEMENT PLAN
U-Stable,no trendsTime
vs total selenium plot for all locations with available data.Trends are denoted by the boo color,if / APPROVED BY:J.WYLIE DATE:8/19/2022 APPENDIX B
there is no color the data could not be analyzed for trends PROJECT MANAGER:J.WYLIE MANN-KENDALL TREND ANALYSIS
•
-Statistically Significant Decreasing Trend • pg/L-mKrograms per liter W.H.WEATHERSPOON POWER PLANT
-Statistically Significant Increasing Trend � LUMBERTON,NORTH CAROLINA
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p.com

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450 450
J J
• 300 -300
4 22
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= Space not used.
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m m
co c0
0 0
Date Date
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LEGEND NOTE 'DUKE DRAWN BY:R.BADUM DATE:7/15/2022
4 Non-detect • Data presented on concentration plots includes all sampling programs. ENERGY REVISEDBV DATE: FIGURE 19
-111-Detect TIME VERSUS TOTAL SULFATE CONCENTRATION
• Data presented may include lab-qualified results.Non-detect analytical results are plotted at the PROGRESS CHECKED Br E.YURKOWCH DATE:7/18/2022 SEEP MANAGEMENT PLAN
corresponding reporting limit.
® Time• vs total sulfate plot for all locations with available data.Trends are denoted by the boa color,if APPROVED BY:J.WYLIE DATE Bn&2022 APPENDIX B
-Stable,no trends there is no color the data could not be analyzed for trends PROJECT MANAGER:J.WYLIE MANN-KENDALL TREND ANALYSIS
-Statistically Significant Decreasing Trend • mg/t milligramsperlifer ' W.H.WEATHERSPOON POWER PLANT
-Statistically Significant Increasing Trend synTerra LUMBERTON,NORTH CAROLINA
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S-5 S-16
600 600
J
co E
c
0 0
o
c 400 c 400
U o
N
m
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U1
a 200 ? 200
1 o
N N
0 C,
O FO
H
J
Date Date
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LEGEND NOTES 4'DUKE DRAWN BY:R.BADUM DATE:1n5/2022
-0-Non_de[ett • Data presented on concentration plots indodes all sampling programs. ENERGY BEVISEDBV: DATE: FIGURE 20
--II-Detect TIME VERSUS TOTAL DISSOLVED SOLIDS CONCENTRATION
___ • Data presented may include lab-qualified results.Non-detect analytical results are plotted at the PROGRESS CHECKED BY:E.YURKOVICH DATE:7/1812 0 2 2 SEEP MANAGEMENT PLAN
corresponding reporting limit.
• Time vs total dissolved solids plot for all locations with available data.Trends are denoted by the boo APPROVED BY:J.WYLIE DATE:8nW2o22 APPENDIX B
I-Stable,no trends color,if there is nocolor the data could not be analyzed for trends PROJECT MANAGER:J.WYLIE MANN-KENDALL TREND ANALYSIS
-Statistically Significant Decreasing Trend • mg/t-milligrams per liter ' W.H.WEATHERSPOON POWER PLANT
Statistically Analyzecant Increasing Trend S\fr)1ef� LUMBERTON,NORTH CAROLINA
No Color-Cannot for Trends
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•
S-5 S-16
•
JD 40
30 30. i
i- tJ
d @
m 20 m 20
Space not used.
iT i-
10. 10
0 0
Date Date
Space not used. Space not used. Space not used.
LEGEND NOTES /,DUKE
DRAWN BY:R.&1DOM DATE:]n SrNgg
-0-Non-detect • Data presented on concentration plots indudes all sampling programs. FIGURE 21
ENERGY —stop- DATE:
If Detect • Data presented may include lab-qualified results.Non-detect analytical results are plotted at the TIME VERSUS TEMPERATURE
corresponding reporting limit. PROGRESS CHECKED BY:E.YURNOVWH DATE:]tlUZ0a3 SEEP MANAGEMENT PLAN
• Time vs temperature plot for all locations with available data.Trends are denoted by the boo color,if APPROVED BY:J.WYLIE DATE:8/19/2022 APPENDIX B
IIStable,no trends there is no color the data could not be analyzed for trends MANN-KENDALL TREND ANALYSIS
-Statistically Significant Decreasing Trend PROJECT MANAGER:J.WYLIE W.H.WEATHERSPOON POWER PLANT
-Statistically Significant Increasing Trend S)/�1T2f� LUMBERTON,NORTH CAROLINA
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S-5 S-16
•
0.5 0 5
OA 0.1
J J
mt m
I:: O>_
c m
~ 0.1 ~ 0.1-
0 0 0.0
Date Date
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LEGEND NOTES f.,DUKE DRAWN BY:R.BADUM DATE:L15/2022
-I}Non-detect • Data presented on concentration plots indudes all sampling programs. ENERGY REVISED BY: DATE: FIGURE 22
-0-Detect TIME VERSUS TOTAL THALLIUM CONCENTRATION
• Data presented may include lab-qualified results.Non-detect analytical results are plotted at the PROGRESS CHECKED BY:E.YURKOVICH DATE:7/18/2022
SEEP MANAGEMENT PLAN
corresponding reporting limit.
MI • Time vs total thallium plot for all locations with available data.Trends are denoted by the box color,if APPROVED BY:J.WYLIE DATE:Bn9no22 APPENDIX B
-Stable,no trSigns there is no color the data could not be anal Zed for trends MANN-KENDALL TREND ANALYSIS
• W.H.WEATHERSPOON POWER PLANT
Y PROJECT MANAGER:J.WYLIE
-Statistically Significant Decreasing Trend pg�L-mmmgramsperlitor
-Statistically Significant Increasing Trend 1 LUMBERTON,NORTH CAROLINA
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S-5 S-16
40 40
J J
E
c
30a' 1 30
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U U
9 20. a 20
1 n -5 Space not used.
d v
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c c
a 10 n 10
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O <n
m m O
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0 0
-
•
. Date .a Date o
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LEGEND NOTES DUKE
DRAWN BY:R.BADUM DATE:7/1512022
Non-detect • Data presented on concentration plots indudes all sampling programs. ENERGY REVISED BY: DATE: FIGURE 23
'AI-Detect TIME VERSUS TOTAL SUSPENDED SOLIDS CONCENTRATION
• Data presented may include lab-qualified results.Non-doted analytical results are plotted at the PROGRESS CHECKED BY:E.YURKOVICH DATE:7/12/2022 SEEP MANAGEMENT PLAN
corresponding reporting limit. APPENDIX B
• Time vs total suspended solids plot for all locations with available data.Trends are denoted by the box APPROVED BY:J.WVLIE DATE:dt W2012
-Stable,no trends MANN-KENDALL TREND ANALYSIS
color,if there is no color the data could not be analyzed for trends PROJECT MANAGER:J.WYLIE
-Statistically Significant Decreasing Trend • mg/L-milli liter W.H.WEATHERSPOON POWER PLANT
grams per
-Statistically Significant Increasing Trend 1'1T2r� www LU MBERTON,NORTH CAROLINA
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•
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15 15.
i
1\)°-<:.111:1-
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Date Date
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LEGEND NOTES t.,DUKE DRAWN BY:R.BADUM DATE:7/15/2022
- -Non-detect • Data presented on concentration plots includes all sampling programs. ENERGY REVISED BY: DATE: FIGURE 24
+Detect TIME VERSUS TOTAL ZINC CONCENTRATION
• Data presented may include lab-qualified results.Non-detect analytical results are plotted at the PROGRESS CHECKED BY:E.YURKOVICH DATE:7/11U2021 SEEP MANAGEMENT PLAN
• Tiesponding reporting limit.
me vs total zinc for all locations with available data.Trends are denoted by the box color,if there is APPROVED BY:J.WYLIE DATE:0n11112022 APPENDIX B
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DRAWN BY:R.BADDM DATE:7I1S/2022
4 Non-detect • Datapresented on concentrationplots includes all sampling ENERGY REVISED BY: DATE: FIGURE ZS
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• Data presented may include lab-qualified results.Non-detect analytical results are plotted at the PROGRESS CHECKED BV:E.YURKOVICH DATE lireie022
TIME VERSUS DISSOLVED METALS CONCENTRATION
corresponding reporting limit SEEP MANAGEMENT PLAN
APPROVED BY:J.WYLIE DATE:8/19/2022 APPENDIX B
• Tiome us totalzinc for all locations with available data.Trends are denoted by the boo color,if there IS
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PROJECT MANAGER:J.WYLIE
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LEGEND NOTES t'DUKE DRAWN BY:R.BADUM DATE:1115I2021
-0-Non-detect • Data presented on concentration plots includes all sampling programs. ENERGY REVISED BY: DATE. FIGURE 25(cont.)
+Detect TIME VERSUS DISSOLVED METALS CONCENTRATION
. • Data presented may Include lab-qualified results.Non-detect analytical results are plotted at the PROGRESS CHECKED BY:E.YURKOVICH DATE:7l10l20z2
SEEP MANAGEMENT PLAN
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Time vs total zinc for all locations with available data.Trends are denoted by the hot color,if there is ! APPROVED BY:J.WYLIE DATE:Bn51201? APPENDIX B
Stable,no trendsI
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no color the data could not be analyzed for trends ` PROJECT MANAGER:1.W YLIE
•
-Statistically Significant Decreasing Trend • Pg�L-micrograms per liter ' W.H.WEATHERSPOON POWER PLANT
-Statistically Significant Increasing Trend LUMBERTON,NORTH CAROLINA
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