1812_DukeMarshall_ILF_Q1_2022 Groundwater Conditions Report_20220501

(� DUKE
ENERGY
May 1, 2022
North Carolina Department of Environmental Quality
Division of Waste Management
Solid Waste Section
1646 Mail Service Center
Raleigh, North Carolina 28778
Attn: Ms. Sarah Moutos (submitted electronically)
Re: Groundwater Condition Quarterly Report — January 2022 through March 2022
Industrial Landfill No.1
Permit No.: 1812-INDUS-2008
Marshall Steam Station
Terrell, North Carolina 28682
Dear Ms. Moutos:
526 South Church St.
Charlotte, NC 28202
Mailing Address
P.O. Box 1006
Mail Code EC 13K.
Charlotte, NC 28201-1006
717-982-0986
In accordance with the NCDEQ DWR September 17, 2021, Phase 2 Permit Modification Approval letter, Duke Energy is
providing the quarterly report describing groundwater conditions in the area of the Marshall Steam Station Industrial
Landfill No.1 (ILF, 1812-INDUS-2008) Phases 2, 3, and 4. The report was prepared by SynTerra on behalf of Duke
Energy. The report is for the quarterly period of January 2022 through March 2022 (Q1 2022).
The quarterly report includes an analysis of groundwater levels and dewatering pump flowrates within Phases 2, 3 and 4,
with updated water level maps, hydrographs, pump flowrate plots, and well construction and water level data tables. An
evaluation of groundwater levels and pump flowrates to determine whether model predictions are being met is included.
All groundwater transducer data, groundwater model trend data, and dewatering pump data are provided in an excel file
format as the report Appendices.
Groundwater conditions in the vicinity of Marshall Steam Station's Industrial Landfill No.1 continue to be monitored and
evaluated. The next quarterly report (Q2 2022) will be submitted by August 1, 2022.
If you need additional information regarding this submittal do not hesitate to email or call me at Ashley. Healy@duke-
energy.com or [phone].
Respectfully submitted,
j4VAi
Ashley Healy, P.G.
Environmental Services
Attachments: Industrial Landfill No.1 (1812-INDUS-2008) Groundwater Conditions Quarterly Report — January 2022
through March 2022 (SynTerra; May 2022)
Appendices in excel format:
1) Appendix A Water Level Monitoring Data Files
2) Appendix B Groundwater Model Predicted Trend Files
3) Appendix C Dewatering/Underdrain Pumping Data Files
cc (via e-mail): Claire Osborn, NCDEQ
Elizabeth Werner, NCDEQ
Ed Mussler, NCDEQ
Kyle Baucom, Duke Energy
Chris Varner, Duke Energy
www.duke-energy.com Page 1 of 2

Jim Malloy, Duke Energy
Tyler Hardin, Duke Energy
Ed Sullivan, Duke Energy
Thomas Colton, SynTerra
Craig Eady, SynTerra
www.duke-energy.com Page 2 of 2

Terra Science &Engineering Consultants
synsynterracorp.com
INDUSTRIAL LANDFILL NO. 1
(1812-INDUS-2008)
GROUNDWATER CONDITIONS QUARTERLY REPORT -
JANUARY 2022 TO MARCH 2O22
FOR
MARSHALL STEAM STATION
8320 EAST CAROLINA HIGHWAY 150
TERRELL, NC 28682
MAY 1, 2022
PREPARED FOR
('DUKE
ENERGY
DUKE ENERGY CAROLINAS, LLC `A I
Ka hryn W. Webb, LG
Senior Peer Reviewer
Thomas Colton
Project Manager
`fit{t{1[fill /
� O
Z o •DENS p•�'L
17
1599 .t�
*y •. F GAS
UG ,P
Craig Eady, NC LG #1599
Senior Project Manager

Groundwater Conditions Quarterly Report —January 2022 to March 2022
Duke Energy Carolinas, LLC - Marshall Steam Station - Industrial Landfill No. 1
Terrell, North Carolina
If-ituxe1Alice] ZIll hLIII M
PAGE
1.0 INTRODUCTION........................................................................................................1-1
1.1 Objectives and Purpose...............................................................................................1-1
1.2 Key Findings.................................................................................................................1-1
2.0 QUARTERLY MONITORING RESULTS......................................................................... 2-1
2.1 Current Groundwater Conditions................................................................................2-1
2.2 Groundwater Trends.................................................................................................... 2-1
2.2.1 Water -Level Hydrographs......................................................................................2-3
2.2.2 Dewatering and Underdrain Pump Performance..................................................2-5
3.0 QUARTERLY WATER -LEVEL REDUCTION ACTIVITIES ................................................... 3-1
4.0 REFERENCES.............................................................................................................4-1
May 2022 Page 1-1
Project: 00.0083.46.05

Groundwater Conditions Quarterly Report -January 2022 to March 2022
Duke Energy Carolinas, LLC - Marshall Steam Station - Industrial Landfill No. 1
Terrell, North Carolina
LIST OF FIGURES
Figure 1
Monitoring Location Map
Figure 2A
Sitewide Water Level Map - Upper Flow Zone (February 2022)
Figure 2B
Area of Focus Water Level Map - Upper Flow Zone (February 2022)
Figure 3A
Background Monitoring Well Hydrographs (GWA-04S/D, MW-04D)
Figure 3B
Perimeter Hydrographs (MW-07 (013-3), ILF-02S/D)
Figure 3C
Northwest of Cell 5 Hydrographs (CLF21-10, CLF21-11)
Figure 3D
CLF-UD and Southwest of Cell 5 Hydrographs (CLF-UD, CLF21-12)
Figure 3E
East of Cell 6 Hydrographs (CLF21-14, CLF21-15)
Figure 3F
Future Phase III and IV Hydrographs (CLF-301, CLF-402)
Figure 3H
Future Phase V (CLF21-13/R, CLF-401)
Figure 3G
South of Future Phase III Hydrographs (CLF-303, CLF-304)
Figure 4A
Cell 5 Pumping Flow Rate Vs. Simulated Flow Rate
Figure 4B
Cell 6 Pumping Flow Rate
Figure 4C
Phase III-V Pumping Flow Rate Vs. Simulated Flow Rate
LIST OF TABLES
Table 1 Groundwater Monitoring Network Well Information and Water Levels
Table 2 Site -Wide Water Level Elevation Data Table
LIST OF APPENDICES
Appendix A Water Level Monitoring Data Files
1. Submittal Data - Locations CLF-301, CLF-303, CLF-304,
CLF-401, CLF-402
2. Submittal Data - Locations CLF21-10, CLF21-11, CLF21-12, CLF21-13/R,
CLF21-14, CLF21-15
3. Submittal Data - Locations GWA-4D, GWA-4S, MW-7(OB-3), ILF-2D, ILF-2S,
MW-4, and CLF-UD
Appendix B Groundwater Model Predicted Trend Files
1. Submittal Data - Locations CLF-301, CLF-302, CLF-303, CLF-304,
CLF-401, CLF-402, CLF-403, CLF-404
2. Submittal Data - Locations CLF21-10, CLF21-11, CLF21-12, CLF21-13/R,
CLF21-14, and CLF21-15
3. Submittal Data - Locations GWA-4D, GWA-4S, MW-7(OB-3), ILF-2D, ILF-2S,
MW-4, and MW-4D
Appendix C Dewatering/Underdrain Pumping Data Files
May 2022 Page 1-2
Project: 00.0083.46.05

Groundwater Conditions Quarterly Report —January 2022 to March 2022
Duke Energy Carolinas, LLC - Marshall Steam Station - Industrial Landfill No. 1
Terrell, North Carolina
LIST OF ACRONYMS
CCR
Coal Combustion Residuals
Cy
cubic yards
Duke Energy
Duke Energy Carolinas, LLC
DWR
Division of Water Resources
Future Phases
ILF Phases III, IV, and V expansion
GPM
gallons per minute
ILF
Industrial Landfill 1812-INDUS-2008
NCDEQ
Report
reporting period
Site
May 2022
North Carolina Department of Environmental Quality
Groundwater Conditions Quarterly Report
First quarter 2022 (January 2022 to March 2022)
Marshall Steam Station
Page 1-3
Project: 00.0083.46.05

Groundwater Conditions Quarterly Report —January 2022 to March 2022
Duke Energy Carolinas, LLC - Marshall Steam Station - Industrial Landfill No. 1
Terrell, North Carolina
1.0 INTRODUCTION
1.1 Objectives and Purpose
SynTerra prepared this Groundwater Conditions Quarterly Report (Report) on behalf of Duke
Energy Carolinas, LLC (Duke Energy) to document the water -level monitoring data and
dewatering/underdrain pumping records in the vicinity of the Industrial Landfill No.1 (Permit
No. 1812-INDUS-2008) at the Marshall Steam Station (Site). This Report is prepared in response
to condition #3 in the North Carolina Department of Environmental Quality (NCDEQ) Division of
Waste Management (DWM) September 17, 2021, Phase II Permit Modification Approval letter.
Data collected during the first quarter of 2022 (January 2021 to March 2022) were used to
evaluate groundwater conditions for the Industrial Landfill No.1 (ILF) Phase II expansion
(includes Cell 5 and Cell 6) and Future Phases. Specifically, this Report evaluates the
groundwater levels, dewatering/underdrain pumping flow rates, and efforts to expedite the
reduction of and maintain groundwater levels near the ILF during the reporting period.
1.2 Key Findings
Key findings of the evaluation conducted during this reporting period include:
• Ash basin coal combustion residual (CCR) excavation activities related to construction of
the ILF Phases III, IV, and V expansion (Future Phases) have generally slowed down for
the landfill expansion. This slowdown is primarily due to:
1) winter weather, where increased precipitation and lower temperatures have
slowed the process of conditioning excavated CCR material prior to disposal in
the active ILF Phase I, and
2) limited air space within the ILF Phase I and reservation of space for plant
production ash.
As a result of the CCR excavation slowdown, dewatering pumps have not been lowered.
• Water levels have been maintained less than or approximately equal to modeled
predictions in most locations. Only 4 locations (ILF-21), CLF21-12, CLF21-13R, and CLF-
401) have water levels greater than the modeled predicted water levels. These locations
(other than ILF-2D, a deep flow zone well upgradient of the ILF) are located within or
near Future Phase V. These observations in CLF21-12, CLF21-13R, and CLF-401 are due
to a slowdown in excavation and increased precipitation.
• Groundwater level data collected during the reporting period were evaluated using
Mann -Kendall analysis to determine water level trends. Findings of the evaluation
include:
o 39% (7 out of 18 monitoring locations) have statistically significant decreasing
groundwater level trends.
May 2022
Page 1-1
Project: 00.0083.46.05

Groundwater Conditions Quarterly Report —January 2022 to March 2022
Duke Energy Carolinas, LLC - Marshall Steam Station - Industrial Landfill No. 1
Terrell, North Carolina
The locations with decreasing trends include: CLF-301, CLF21-15, GWA-
4S, GWA-41D, MW-4, MW-41D, and MW-7(OB-3).
■ These locations, with the exception of CLF-301, are upgradient of or
along the eastern perimeter of the ILF. CLF-301 is located within Future
Phase III.
■ Most of these wells and piezometers are relatively remote from the Cell 5
Underdrain and the Cell 6 and Future Phases dewatering operations.
Therefore, the groundwater level decreases are a delayed response to
previous excavation and dewatering. The decrease of groundwater levels
at CLF-301 are likely a result of the excavation that took place during the
reporting period.
o 39% (7 out of 18 monitoring locations) have statistically significant increasing
groundwater level trends.
■ The locations with increasing trends include: CLF-303, CLF-304, CLF21-10,
CLF21-11, CLF21-12, CLF21-13R, and ILF-21).
ILF-21) is a deep flow zone monitoring well upgradient of the ILF. CLF-303
and CLF-304 are downgradient of the Future Phases. The remaining
locations with increasing trends are located on the western perimeter of
the ILF.
■ The groundwater levels in these locations increased as a result of the
slowdown in excavation and increased precipitation.
o 22% (4 out of 18 monitoring locations) have stable conditions with no significant
groundwater level trends.
■ The locations with stable conditions include CLF-401, CLF-402, CLF21-14,
and ILF-2S.
■ CLF-401 and CLF-402 are located in Future Phases IV and V. CLF21-14 is
located on the eastern perimeter of the ILF. ILF-2S is a shallow flow zone
monitoring well upgradient of the ILF.
• Dewatering in ILF Phase II, Cell 5 and Cell 6, and the ILF Future Phases area removed
approximately 17.1 million gallons of water in Quarter 12022. This is more than the
volume of water removed during the previous quarter.
• Pumping flow rate from the Cell 5 sump has stabilized. The pumping in Cell 6 was not
modeled, but pumping flow rates continue to be relatively stable. The Future Phases
dewatering pumping flow rate continues to increase, especially following precipitation.
• Although the ash basin excavation progress slowed due to winter weather and limited
air space within the ILF Phase I, excavation of CCR and dewatering within the ILF Future
Phases continues to lower groundwater levels in the area.
May 2022 Page 1-2
Project: 00.0083.46.05

Groundwater Conditions Quarterly Report — January 2022 to March 2022
Duke Energy Carolinas, LLC - Marshall Steam Station - Industrial Landfill No. 1
Terrell, North Carolina
2.0 QUARTERLY MONITORING RESULTS
The established network of temporary and long-term piezometers and groundwater wells for
monitoring groundwater conditions in the ILF Phase II expansion area is depicted on Figure 1.
Piezometer and groundwater well construction information, with water level and groundwater
elevations, for the monitoring network is included on Table 1. Note three additional
piezometers were installed in March 2022 and water level data from the new piezometers are
not included in the evaluation.
2.1 Current Groundwater Conditions
Site -wide water levels collected on February 14, 2022 for the upper (shallow) flow zone were
used to generate groundwater level maps (Figure 2A and 2113). Water level data and
groundwater elevations are included on Table 2.Observed groundwater levels during this
reporting period indicate:
• Groundwater is generally flowing north to south through the ILF area
(Figure 2A and 213).
Some groundwater levels within and near the ILF have decreased slightly, relative to
groundwater levels from Quarter 4 2021. However, most of the groundwater levels near
the ILF remain relatively the same as in Quarter 4 2021.
• Underdrain operations in Cell 5 have maintained a cone of groundwater depression
around the Cell 5 blanket underdrain sump (CLF-UD, Figure 213).
The excavation that took place during the reporting period focused on the Future Phases area,
as shown on Figures 2A and 2B.
2.2 Groundwater Trends
A series of groundwater monitoring wells, piezometers, and the Cell 5 underdrain pump
transducer monitor water level trends (Figures 3A through 3H). The following are key
observations of overall trend data:
• Groundwater level data collected between July 2021, when close monitoring started,
and the end of March 2022 were evaluated using Mann -Kendall analysis to determine
water level trends. Statistically significant decreasing trends were observed in 17 of 18
locations. A statistically significant increasing trend was observed at one location (ILF-
2S); since July 2021, a small water level increase (0.2 feet) has been observed in ILF-2S.
• Groundwater level data for the reporting period (January through March 2022) were
also evaluated using Mann -Kendall analysis. Findings of the evaluation include:
May 2022
o 39% (7 out of 18 monitoring locations) have statistically significant decreasing
groundwater level trends.
Page 2-1
Project: 00.0083.46.05

Groundwater Conditions Quarterly Report — January 2022 to March 2022
Duke Energy Carolinas, LLC - Marshall Steam Station - Industrial Landfill No. 1
Terrell, North Carolina
■ The locations with decreasing trends include: CLF-301, CLF21-15, GWA-
4S, GWA-41D, MW-4, MW-41D, and MW-7(OB-3).
These locations, with the exception of CLF-301, are located upgradient of
or along the eastern perimeter of the ILF. CLF-301 is located within
Future Phase III.
■ These wells and piezometers are relatively remote from the Cell 5
Underdrain and the Cell 6 and Future Phases dewatering operations.
Therefore the data reflect a delayed response to previous excavation and
dewatering. The continued decrease of groundwater levels at CLF-301
are likely a result of the excavation that took place in the Future Phases
area during the reporting period.
o 39% (7 out of 18 monitoring locations) have statistically significant increasing
groundwater level trends.
■ The locations with increasing trends include: CLF-303, CLF-304, CLF21-10,
CLF21-11, CLF21-12, CLF21-13R, and ILF-21).
ILF-21) is a deep flow zone monitoring well upgradient of the ILF. CLF-303
and CLF-304 are downgradient of the Future Phases. The remaining
locations with increasing trends are located on the western perimeter of
the ILF.
■ The groundwater levels in these locations increased as a result of the
slowdown in excavation and increased precipitation.
o 22% (4 out of 18 monitoring locations) have stable conditions with no significant
groundwater level trends.
■ The locations with stable conditions include: CLF-401, CLF-402, CLF21-14,
and ILF-2S.
■ CLF-401 and CLF-402 are located in Future Phases IV and V. CLF21-14 is
located on the eastern perimeter of the ILF. ILF-2S is a shallow flow zone
monitoring well upgradient of the ILF.
Since July 2021, when close monitoring of groundwater conditions started, the greatest
reduction in groundwater levels has occurred at the following locations, CLF21-14 (-3.7
feet), CLF21-15 (-3.7 feet), CLF21-11 (-3.2 feet), GWA-41) (-3.0 feet), MW-4 (-2.9 feet),
GWA-4S (-2.8 feet), CLF21-12 (-2.7 feet), and MW-4D (-2.7 feet). The reduction in
groundwater levels in the piezometers within and adjacent to Cell 5 (CLF21-11 and
CLF21-12) occurred during the initial Cell 5 underdrain construction and operations. The
reduction in groundwater levels in piezometers CLF21-14 and CLF21-15 occurred as a
result of focused excavation of CCR from the ash basin finger associated with ILF Phase II
Cell 6 and Future Phase III. Slowed excavation progress and increased precipitation has
led to stabilized water levels in that area during the reporting period (Figure 3E).
May 2022 Page 2-2
Project: 00.0083.46.05

Groundwater Conditions Quarterly Report — January 2022 to March 2022
Duke Energy Carolinas, LLC - Marshall Steam Station - Industrial Landfill No. 1
Terrell, North Carolina
Continued operation of the Cell 5 underdrain has maintained reduced water levels in
that area. GWA-4S/D and MW-4/D are monitoring wells upgradient and outside of the
ILF have had steady water level decreases since July 2021 (Figure 3A).
The observed groundwater trends were compared to model predictions. The following
observations were made:
o Groundwater level trends at 3 of 18 locations (ILF-2S, CLF21-10, and CLF21-15)
are consistent with model predictions.
■ ILF-2S and CLF21-10 were relatively consistent with the model
predictions throughout the reporting period. CLF21-15 became
consistent with model predictions late in the reporting period.
Water Levels in ILF-2S and CLF21-10 are similar to predicted water levels.
Water Levels in CLF21-15 are less than predicted water levels.
o Groundwater level trends at 5 of 18 locations (GWA-4S, GWA-4D, MW-4, MW-
4D, and MW-7(OB-3)) are decreasing faster than model predictions.
■ Water Levels in these locations are less than predicted water levels.
o Groundwater level trends at 4 of 18 locations (CLF21-14, CLF-301, CLF-401, and
CLF-402) are decreasing slower than model predictions or are stable compared
to the model predictions of decreasing trends.
■ Water levels in CLF-301 and CLF-402 are similar to predicted water levels.
Water levels in CLF21-14 are less than predicted water levels. Water
levels in CLF-401 are greater than predicted water levels.
■ The stable groundwater conditions in these locations are likely a result of
the slowdown in excavation and increased precipitation.
o Groundwater level trends at 6 of 18 locations (CLF-303, CLF-304, CLF21-10,
CLF21-11, CLF21-12, CLF21-13R, and ILF-2D) are increasing.
Water levels CLF-303, CLF-304, and CLF21-11 are similar or less than
predicted water levels. Water levels in CLF21-14 are below predicted
water levels. Water levels in CLF-401 are above predicted water levels.
■ The groundwater levels in these locations increased as a result of the
slowdown in excavation and increased precipitation.
2.2.1 Water -Level Hydrographs
At the beginning of the reporting period, 7 monitoring wells and 11 piezometers in and
around the ILF area existed and were monitored using pressure transducers (Figure 1).
An additional water level monitoring location within the Cell 5 underdrain sump (CLF-
UD) was added during late 2021. During this reporting period, three piezometers
(CLF22-305, CLF22-306, and CLF22-307) were installed. Duke Energy provided well
May 2022 Page 2-3
Project: 00.0083.46.05

Groundwater Conditions Quarterly Report — January 2022 to March 2022
Duke Energy Carolinas, LLC - Marshall Steam Station - Industrial Landfill No. 1
Terrell, North Carolina
May 2022
construction records (GW-1 Forms) and boring logs for each piezometer to DWM under
separate submittals.
No water level data from the newly installed piezometers was collected during the
reporting period. The piezometers were installed on March 21 and 22, 2022, and
transducers were installed in early April 2022. The new piezometers were installed after
the quarterly water level sweep was completed.
Pressure transducers are used to record high resolution groundwater elevation data for
evaluation of groundwater conditions resulting from dewatering and excavation.
Transducer data in Excel spreadsheets is included in Appendix A. Manual water level
measurements and transducer records were used to generate hydrographs. Predicted
groundwater level trends from the transient groundwater models are included in the
hydrographs to compare the model results with observed groundwater level trends
(Figures 3A through 3H). Appendix B contains Excel spreadsheets with the predicted
transient groundwater level trends exported from the models.
Upgradient of the Phase II Expansion:
• Monitoring locations GWA-4S/D and CLF21-10 are located west of the ILF
Phase II expansion (Figure 1). Water levels are decreasing at GWA-4S and
GWA-41D (Figure 3A). Water levels are slightly increasing in CLF21-10 (Figure
3C). Shallow and deep water levels at GWA-4S/D decreased but at a slower
rate. Measured groundwater levels in GWA-4S and GWA-41D are lower than
water levels predicted by the model. The groundwater level at CLF21-10 is
relatively stable and consistent with model predictions.
• ILF-2S/D are located north of the ILF (Figure 1). The deep water level at ILF-
2D increased slightly during the reporting period. The shallow water level at
ILF-2S was generally stable (Figure 313).
• MW-4/D are located east of the ILF Phase II expansion (Figure 1). Water
levels in both the shallow and bedrock wells continue to decrease and are
lower than the model predicted (Figure 3A).
Within the Phase II Expansion:
• A transducer, identified as CLF-UD, was installed to monitor the Cell 5
underdrain sump water level (Figure 1). The water levels within the sump
demonstrate that the underdrain continues to operate as intended,
maintaining a steady water level controlled by the pump settings (Figure 313).
Note the increases in the sump's water levels are related to temporary
testing for adjustments to the pump's settings and cycling.
Page 2-4
Project: 00.0083.46.05

Groundwater Conditions Quarterly Report — January 2022 to March 2022
Duke Energy Carolinas, LLC - Marshall Steam Station - Industrial Landfill No. 1
Terrell, North Carolina
May 2022
Perimeter of the Phase II Expansion:
Monitoring locations CLF21-11, CLF21-12, and CLF21-13R are located east
and south of Cell 5. The water levels trends for CLF21-11, CLF21-12, CLF21-
13R were stable or increased (Figures 3C, 313, and 3H).
Monitoring locations CLF21-14 and CLF21-15 are located west of Cell 6
(Figure 1). Water levels in CLF21-14 were stable. Water levels in CLF21-15 are
decreasing but the rate of decrease has slowed (Figure 3E). CLF21-14 is
located near the ash basin finger where CCR excavation is occurring and
CLF21-15 is upgradient of CLF21-14.
Downgradient of the Phase II Expansion (Future Phases area):
• Monitoring location MW-7 (013-3) is located downgradient of the ILF Phase II
expansion (Figure 1). Shallow water levels at MW-7 (013-3) continue to
decrease (Figure 313). The water level in MW-7 (013-3) is less than model
predictions.
• Monitoring locations CLF-301 is located within the Future Phase III
expansion, while CLF-303 and CLF-304 are located downgradient of the
Future Phase III expansion (Figure 1). Water levels in CLF-301 were
decreasing to stable (Figure 3F). Water levels in CLF-303 and CLF-304
increased slightly (Figure 3G). For CLF-301, water levels continue to decrease.
For CLF-303 and CLF-304, water levels continue to remain lower than the
model predicted elevations even with the recent increasing trends.
• Monitoring locations CLF-401 and CLF-402 are located within the Future
Phase IV expansion (Figure 1). Water levels were decreased or stabilized
(Figure 3F and 3H). Water levels in CLF-401 intercepted the model predicted
trend line toward the end of the reporting period. Water levels in CLF-402
are similar to model results with the decreasing trend being slower than the
model predictions.
2.2.2 Dewatering and Underdrain Pump Performance
Two excavation and construction dewatering pumps are installed within or
downgradient of ILF Phase II, Cell 6, and the ILF Future Phases (Figure 1). An underdrain
pump is installed within the Cell 5 underdrain (CLF-UD). The pumps remove
groundwater and, for Cell 6 and the Future Phases areas, precipitation runoff.
The Cell 5 underdrain pump does not receive precipitation runoff; the underdrain is
enclosed. The pump in Cell 5 is intended to maintain groundwater levels at elevation
811.04 feet. The pump in Cell 6 is intended to remove groundwater seepage flow and
precipitation runoff. The Future Phases pump is intended to remove water from the
active excavation area for the ILF expansions, and is periodically lowered during
Page 2-5
Project: 00.0083.46.05

Groundwater Conditions Quarterly Report — January 2022 to March 2022
Duke Energy Carolinas, LLC - Marshall Steam Station - Industrial Landfill No. 1
Terrell, North Carolina
excavation to continue drawing down water levels. Water removed by each pump is
discharged to the lower portion of the ash basin.
Groundwater modeling was used to predict the flow rates of an operational Cell 5
underdrain sump and flow rates of the excavation dewatering in the Future Phases
footprint (Cell 6 dewatering was not included in the original transient model). The
predictive model assumes that the Cell 5 underdrain begins operating in January 2022
and that no dewatering was conducted during installation of the underdrain or prior to
completion of the underdrain. This assumption is a limitation of the model and results in
an initial conservative (high) predicted flow rate from the Cell 5 underdrain, since
dewatering did occur during construction for installation of the underdrain. Cell 5
construction dewatering operations transitioning into underdrain operations has
resulted in lower initial flow rates than predicted by the model due to this difference in
model assumptions and the actual field activities (Figure 4A).
The predicted start of pumping at the Cell 5 underdrain aligns with actual start of
pumping from the Cell 5 sump and the accelerated dewatering schedule (Figure 4A).
Flow rates downgradient of excavation and construction activities for Cell 6 continue to
be monitored and are shown in Figure 413.
Predicted and measured flow rates from the Future Phases excavation dewatering
pump are shown in Figure 4C. No temporal adjustments were made for flow rate data
because the model assumes dewatering is occurring during the entire predictive model
time period, which is consistent with field operations.
The Cell 5 underdrain pump has been operational for six months and the pumping rate
appears to be relatively stable at approximately 8.5 gallons per minute (gpm). The
measured flow rate reasonably matches the predicted steady state flow rate of 18 gpm
estimated using the steady state blanket underdrain model presented in Technical
Memorandum: Modeling Support for the ILF Phase 2 Permit to Construct Modifications
(SynTerra, 2021). The Cell 5 underdrain pump removes water in order to maintain the
groundwater levels in a localized area below the top of the blanket underdrain; the flow
rate is expected to slowly decrease over time as excavation and dewatering continue
downgradient. The Cell 6 dewatering pump remains stable with increases related to
precipitation. Precipitation during the reporting period has been more intense and
frequent than during Quarters 3 and 4 of 2021. The flow rate of the Future Phases
dewatering pump is increasing as the model predicted with temporary increases related
to precipitation.
ILF Cell 5, Cell 6, and Future Phases pumping data, including the calculated monthly total
volume pumped and monthly average flow rate, per location, is included in Appendix C.
Combined pumping operations for Cell 5, Cell 6, and the Future Phases area have
removed approximately 17.1 million gallons of water during the reporting period,
May 2022 Page 2-6
Project: 00.0083.46.05

Groundwater Conditions Quarterly Report — January 2022 to March 2022
Duke Energy Carolinas, LLC - Marshall Steam Station - Industrial Landfill No. 1
Terrell, North Carolina
resulting in approximately 9.6 million gallons more than during Q4 2021. Since initiating
flow rate monitoring (mid -September 2021 through March 2022), a total of
approximately 25.8 million gallons of water have been removed from the ILF Phase II
and Future Phases area.
For each pump, the average flow rates for the reporting period and each month are
listed below.
• The Cell 5 underdrain pump had an average flow rate of 8.5 gpm overall during
the reporting period, and monthly average flow rates of:
o 8.2 gpm during January 2022,
o 8.3 gpm during February 2022,
o 8.9 gpm during March 2022.
• The Cell 6 Pump had an average flow rate of 27.2 gpm overall during the
reporting period, and monthly average flow rates of:
o 33.3 gpm during January 2022,
o 6.3 gpm during February 2022,
o 42.1 gpm during March 2022.
• The Future Phases Pump had an average flow rate of 94.7 gpm overall during the
reporting period, and monthly average flow rates of:
o 98.7 gpm during January 2022,
o 77.5 gpm during February 2022,
o 108.0 gpm during March 2022.
May 2022
Page 2-7
Project: 00.0083.46.05

Groundwater Conditions Quarterly Report — January 2022 to March 2022
Duke Energy Carolinas, LLC - Marshall Steam Station - Industrial Landfill No. 1
Terrell, North Carolina
3.0 QUARTERLY WATER -LEVEL REDUCTION ACTIVITIES
Efforts made during the reporting period by Duke Energy to safely expedite the reduction of
groundwater levels within the ILF Phase II expansion and the Future Phases include:
Cell 5
Continued underdrain operations, with an average flow rate of approximately 8.5 gpm.
• Continued landfill construction, with completion of the compacted soil liner and ongoing
installation of the geosynthetics.
Cell 6
• Continued landfill construction, with installation of the subgrade; the majority of the
cell's subgrade is approaching the final grade.
• Dewatering downgradient of Cell 6 is being maintained, with an average flow rate of
approximately 27.2 gpm.
Future Phases
• Continued excavation of CCR.
• Dewatering of excavation rim ditches is being maintained, with an average flow rate of
May 2022
approximately 94.7 gpm.
Three piezometers (CLF22-305, CLF22-306, and CLF22-307) were installed within and
downgradient of the Future Phases footprint to monitor water levels within and around
the Future Phase III area as excavation and dewatering efforts continue.
Page 3-1
Project: 00.0083.46.05

Groundwater Conditions Quarterly Report — January 2022 to March 2022
Duke Energy Carolinas, LLC - Marshall Steam Station - Industrial Landfill No. 1
Terrell, North Carolina
4.0 REFERENCES
SynTerra (2021). Technical Memorandum: Modeling Support for the ILF Phase 2 Permit to
Construct Modification Marshall Steam Station. October 5, 2021.
May 2022
Page 4-1
Project: 00.0083.46.05

Groundwater Conditions Quarterly Report — January 2022 to March 2022
Duke Energy Carolinas, LLC - Marshall Steam Station - Industrial Landfill No. 1
Terrell, North Carolina
FIGURES
L7
synTerra
Science & Engineering Consultants

'
L GW<
_ y
STRUCTURAL FILL
CCB0031
♦' °o
♦.m.�.
910� 900��
E90_ —880—�
CLF21-18=� =850
CLF21-11
CLF-U D
c
CLF21-13
n CLF-3
CLF-401
•/ =�s10
�p
CLF-403 \l CLF-402
111777 �_
CLF22-305 0
0 4 0 0
rI F-Ana .
V '� r.FAIlliliza—m►_ r
CLF21-15
l
I ,
I �
`.
4.
' � I
I
I I v2
♦ o
J
LEGEND
LONG-TERM PIEZOMETER AND/OR
GROUNDWATER MONITORING WELL
ie TEMPORARY PIEZOMETER
e DEWATERING OR UNDERDRAIN PUMP
I� ABANDONED PIEZOMETER
ASH BASIN WASTE BOUNDARY
- - - - - GEOGRAPHIC LIMITATION
LANDFILL COMPLIANCE BOUNDARY
STRUCTURAL FILL BOUNDARY
LANDFILL BOUNDARY
LEACHATE BASIN
- - DUKE ENERGY CAROLINAS PROPERTY LINE
TOPOGRAPHIC CONTOUR (10' INTERVAL)
STREAM (MCKIM & CREED)
® WETLAND (MCKIM & CREED)
NOTES:
1. THE CLF-UD LOCATION WAS FORMERLY KNOWN AS CELL 5 PUMP.
2. ALL BOUNDARIES ARE APPROXIMATE.
\3. THE STREAMS AND WETLANDS JURISDICTIONAL DETERMINATION WAS APPROVED
BY THE US ARMY CORPS OF ENGINEERS ON OCTOBER 25, 2017 (SAW-2015-01412).
WETLANDS AND STREAMS BOUNDARIES WERE OBTAINED FROM AMEC FOSTER
WHEELER ENVIRONMENTAL AND INFRASTRUCTURE, INC. NATURAL RESOURCES
TECHNICAL REPORT (NRTR) DATED JUNE 2015.
4. PROPERTY BOUNDARY PROVIDED BY DUKE ENERGY CAROLINAS.
5. THE TOPOGRAPHY IS SHOWN FOR REFERENCE PURPOSES ONLYAND SHOULD
NOT BE USED FOR DESIGN OR ENGINEERING PURPOSES. TOPOGRAPHY PROVIDED
BY TRANSASH.
6. MAXAR SATELLITE IMAGERY OBTAINED FROM ESRI ONLINE, COLLECTED AUGUST
24, 2021.
7. DRAWING HAS BEEN SET WITH A PROJECTION OF NORTH CAROLINA STATE PLANE
COORDINATE SYSTEM RIPS 3200 (NAD83).
GRAPHIC SCALE
DUKE 200 0 200 400 FIGURE 1
ENERGY® MONITORING LOCATION MAP
.� CAROLINAS (IN FEET)
DRAWNBY:W.PRATER DATE:01/20/2022 GROUNDWATER CONDITIONS QUARTERLY REPORT
�• REVISED BY: R. KIEKHAEFER DATE: 04/28/2022 JANUARY 2022 THROUGH MARCH 2O22
CHECKED BY: T. COLTON DATE: 04/28/2022 MARSHALL STEAM STATION
APPROVED BY: T. COLTON DATE: 04/28/2022
synTerra PROJECT MANAGER: T. COLTON TERRELL, NORTH CAROLINA
www.synterracorp.com

SEE FIGURE 2B FOR DETAILED WATER LEVEL BG-1 S
f CONTOURS AND ADDITIONAL WATER LEVEL
• y�yy "' !� �!"'^' �o MEASUREMENTS TAKEN IN THE AREA OF FOCUS 811.4
} "r +_ r -_sso g3 GWA-8S
ILF-2S Sao s1_
822.97 '
� T y
/ ,, t ,' , •� GWA-4S p° ° 430 9zo I a1 y o
A�yT
MW-4 848.56 829.87 �o
�.' / ,>/--_ye
e ., GWA-5S LEGEND
p ago
CLF-UD �t BP, BELOW 806.88 .
• ° rr� j $ / .aON 811.04 e°° �� �- BG-2S MW-ss WELL ID
,�� / �• 815 809.54 765.80 WATER LEVEL (NAND 88, FEET)
GWA-14S r r �r /. I� CLF-301 r y- ��y MONITORING WELL
870.97 CLF-401 �.� ' - t I PIEZOMETER
814.90
GWA-3S g2y 813.65 I sb° 05.97 OV7 50
836.83 _ BACKGROUND MONITORING WELL
♦ � n/ CELL 6 PUMP
♦ �, a° 3 StioU ��Zo« y7t'``CLF-402 l% 813.01' sa° ABANDONED MONITORING WELL
PVSF-o' Jet j �� 809.18 /
)\`; 7 MW-7 AL-3S % ABANDONDED PIEZOMETER
` ' s3 CLF-403 �i� CLF-302 8's (OB-g) 808.95 -� DEWATERING OR UNDERDRAIN PUMP
° 1 1 If CLF-303 816.42 ` - INFERRED WATER LEVEL CONTOUR (5' INTERVAL)
MW-13S 1 I eoy 799.41 110 r/� GROUNDWATER FLOW DIRECTION
845.50 { �j 1 , .• PVSF-2S CLF-404 �, 5S
9�o AL-2S ' \ AREA OF EXCAVATION, QUARTER 1 2022
A � i AB-1/SL �
/i ASH BASIN WASTE BOUNDARY
FUTURE PHASES 802.90
PUMP" CCR-16S GWA-7S r�( - - GEOGRAPHIC LIMITATION
+ � ` ` N ` AB- 03 BP, BELOW 795.62 799.27 d 3 �^ LANDFILL COMPLIANCE BOUNDARY
` , _
1 ,u , STRUCTURAL FILL BOUNDARY
` CLF-304 MW-2 s__, . CCR-15S
798 70 785.93 BP, BELOW 783.25 MW-14S 0 - LANDFILL BOUNDARY
AB-14S
' ♦, 81195 CCR-15D . BP, BELOW 761.36 1 ( LANDFILL CELL 5 AND 6 BOUNDARY
�,: AB-12SL 'AB-10SL AB-10S 788.09 LEACHATE BASIN
` I .r Y
GWA-13S i pVSF-4S , ` 3` ear AB-14DU No Access 783.76 _
867.63 848.66 ` 812.59 p .�L A�� 784.90 $°° \ GWA 10S
` F DRY, BELOW 755.32 -DUKE ENERGY CAROLINAS PROPERTY LINE
No Access �. 9 TOPOGRAPHIC CONTOUR (10' INTERVAL)
` AL-1 S
-)l STREAM (MCKIM & CREED)
DRY, BELOW GWA-15S
1 , ` A�B28 � AB-9S 768.43 °~. 749.34 -T WETLAND (MCKIM & CREED)
;., o PVSF-1S ii� 783.39 Noyes:
831.34 T11A.
AB-8DU 41 MV�/_1 GWA-11 S 1. WATER LEVELS WERE COLLECTED ON FEBRUARY 14, 2022.
o I I 791.68 • BP, BELOW BP, BELOW744.10 2. ' - DEWATERING OR UNDERDRAIN PUMP ELEVATION. WATER LEVEL CONTROL
GWA-12S J l .. MW-6S POINT.
M842. S / s DRY, BELOW 762.58 3. "- FUTURE PHASES PUMP LOCATION IS FOR REFERENCE ONLY. NOTA WATER
870.37 I I 842.13 / �` _ 820 y 87p AB-21 S / ° 9 o LEVEL CONTROL POINT.
f 784.69 '$' CCR-9S ♦ ' 4. WATER LEVEL CONTOURS WERE DERIVED USING DATA COLLECTED FROM
' /''•� .o 'yj 761.03 . � MONITORING WELLS AT THE SITE ON FEBRUARY 14, 2022. ADDITIONAL
_ /rf
v-nPIEZOMETERS WERE USED TO INTERPRET CONTOURS IN THE AREA OF FOCUS,
S-8 ' j1 ! di/+ WHICH ARE SHOWN IN FIGURE 2B.
829.37 �� / � i 1 ��\� � , \� e il�. A6 .18 ♦ S.W.E.-WATER ELEVATION (APPROXIMATE).
MS-9 I ' I iii l \ MW-7S / s. BP -BELOW BLADDER PUMP.
q�y 827.42 ~„I/ 1 AB-4S -` \ DRY, BELOW 752.50 • MW-10S I/, 7. ELEVATIONS ARE REFERENCED TO THE NORTH AMERICAN VERTICAL DATUM OF
/{ 786.50 1988 (NAVD 88).
755.73
AB-5S =' 1• AB-4SL $ o . �� 8. THE STREAMS AND WETLANDS JURISDICTIONAL DETERMINATION WAS
j MW 8S ♦ APPROVED BY THE US ARMY CORPS OF ENGINEERS ON OCTOBER 25, 2017 SAW-
1 795.39 785.36 •;. AB-3S `� ♦ 756.95 ♦ 2015-01412). WETLANDS AND STREAMS BOUNDARIES WERE OBTAINED FROMAMEC
Qo % DRY, BELOW 785.91 AB-2S I 1 FOSTER WHEELER ENVIRONMENTAL AND INFRASTRUCTURE, INC. NATURAL
AB-5DU 1 �•� ` RESOURCES TECHNICAL REPORT (NRTR) DATED JUNE 2015.
Mh �. MS-15 795.92 p x' 759.35
r� i � � � MW-9S ♦♦ 9. THE TOPOGRAPHY IS SHOWN FOR REFERENCE PURPOSES ONLY AND SHOULD
818.55 ' 757.84 NOT BE USED FOR DESIGN OR ENGINEERING PURPOSES. TOPOGRAPHY PROVIDED
MS 11 CCR-2S CP-1S ® BYTRANSASH.
o ° /:.. c BP, BELOW ��
e� •, 825.44 ' ;'✓ \ f 783.02 783.47 CCR-5S • 10. PROPERTY BOUNDARY PROVIDED BY DUKE ENERGY CAROLINAS.
758.29 i
MS-13 '� 4_ ` 8 �. 11. ALL BOUNDARIES ARE APPROXIMATE.
811.05 s MS-14 CCR-1 S ��I �� �/ s 12. MAXAR IMAGERY OBTAINED FROM ESRI ONLINE ON MARCH 17, 2022. AERIAL
es 807.78 t '91.35 758A5cc M S • 7 WAS COLLECTED ON OCTOBER 19, 2021.
° CP-2S GWA-1 "S ���.fi� - ♦ 13. DRAWING HAS BEEN SET WITH A PROJECTION OF NORTH CAROLINA STATE
r A • PLANE COORDINATE SYSTEM FIPS 3200 (NAD83).
ti ,., :-•t MS-12 GP-2S 794.12 759.43
♦ !• '�y # �r 812.46 • 804.15 GRAPHIC SCALE
CCR-3S 500 0 500 1,000 FIGURE2A
• _ ' . �� ,('jam GWA-2S 756.64 DUKE SITEWIDE WATER LEVEL MAP
^/ iii 801.64 4 ENERGY®
r ray 820 CAROLINAS (IN FEET)
UPPER FLOW ZONE (FEBRUARY 2022)
DRAWN BY: W.PRATER DAT E: 02/25/2022 GROUNDWATER CONDITIONS QUARTERLY REPORT
` 800.41 802 59 stove e CP-3S /�^ REVISED BY: R. KIEKHAEFER DATE:04/28/2022 JANUARY 2022 THROUGH FEBRUARY 2022
.� BP, BELOW CHECKED BY: T. COLTON DATE: 04/28/2022
784.81 r'. APPROVED BY: T.COLTON DATE:04/28/2022 MARSHALL STEAM STATION
synTerra PROJECT MAww .sT. ent rr TERRELL, NORTH CAROLINA
r www.svnterracoro.com

�''�• r p�FlM r'+rii ILF-2Sn . , [
e, a• ��.� _ ,f.a< r �0e �M 842.17
I
000e
Ll
.000
vel
0.0 �100010 1/'�/i CLF21-10 Q //
• / 840.61
LEGEND
/ / _ `soo Mw-6s WELL ID
880 �s5.ao WATER LEVEL (NAVD 88, FEET)
/ / /� gso►w 1 Ie MONITORING WELL
•GWA-4S ` CLF21-18 850 C PIEZOMETER
1-1848.56 CLF21-11 ��
�� MW-�.•,.
000 ' / 82525 CLF21-19 829.87 4 - y BACKGROUND MONITORING WELL
-. / / • / / °' ��' ABANDONED MONITORING WELL
001,
$A�. / CLF21-16 ABANDONED PIEZOMETER
'oo825 aep lie DEWATERING OR UNDERDRAIN PUMP
$p2 / / ,w♦/` 2 LF LID�` ` CLF21-20 INFERRED WATER LEVEL CONTOUR (2.5' INTERVAL)
sue„ '®/ o-lb I / C811 044 �� - -► GROUNDWATER FLOW DIRECTION
000 .'` ® . ��5 ! 1+�`-- e CLF21-15 AREA OF EXCAVATION, QUARTER 1 2022
�t / 81s / 822.75
/# .� I .v. h• CLF21-12 3o L�- CLF21-17 / ASH BASIN WASTE BOUNDARY
// / Asti 818.52 �� CLF21-14 h
/ . / LF21-13 �� 817.91 4 820 GEOGRAPHIC LIMITATION
CLF21-13R
���jjj/// � ro � y $so -�� c 4 LANDFILL COMPLIANCE BOUNDARY
GWA 3S BASIN�\ 817.98 Q �� _ STRUCTURAL FILL BOUNDARY
5 ( _----��► CLF-301 �,
Xl0 836.83 �ti 40 CLF-401 �= 814.90 / LANDFILL BOUNDARY
�.r / /y� f �( 813.65 ` `�= �� 8 �f t • "' • - - LANDFILL CELL 5 AND 6 BOUNDARY
, CELL 6 PUMP
\\ I \1 1 / LEACHATE BASIN
-813.01*
DUKE ENERGY CAROLINAS PROPERTY LINE
/'' TOPOGRAPHIC CONTOUR (10' INTERVAL)
/ N� a CLF-402 - f 0; ' / > - STREAM (MCKIM & CREED)
p v A, 809.18 I n A\ .�
WETLAND MCKIM & CREED
�e MW-7 (OB-3) NOTES:
616.42
1. WATER LEVELS WERE COLLECTED ON FEBRUARY 14, 2022.
2. * - DEWATERING PUMP ELEVATION. WATER LEVEL CONTROL POINT.
ti / ; 10 3. ** - FUTURE PHASES PUMP LOCATION IS FOR REFERENCE ONLY. NOT WATER
Lk ' 8 LEVEL CONTROL POINT.
r-_ �` 4. ELEVATIONS ARE REFERENCED TO THE NORTH AMERICAN VERTICAL DATUM
/IN�:l.
805 OF 1988 (NAVD 88).
A o t. JC �,yr� •
00i / � \ 4"• 5. THE STREAMS AND WETLANDS JURISDICTIONAL DETERMINATION WAS
r / .- �• APPROVED BY THE US ARMY CORPS OF ENGINEERS ON OCTOBER 25, 2017 (SAW-
2015-01412). WETLANDS AND STREAMS BOUNDARIES WERE OBTAINED FROM
-�:r ♦ a,. �,, ;,,� CLF-303 '� T AMEC FOSTER WHEELER ENVIRONMENTAL AND INFRASTRUCTURE, INC.
/•� _ a.• �' NATURAL RESOURCES TECHNICAL REPORT (NRTR) DATED JUNE 2015.
799.41
• � . - �y g0 6. THE TOPOGRAPHY IS SHOWN FOR REFERENCE PURPOSES ONLY AND SHOULD
1 ` s ^ t w o �• O / / o NOT BE USED FOR DESIGN OR ENGINEERING PURPOSES. TOPOGRAPHY
Bag PROVIDED PROVIDED BYTRANSASH.
I /. '►' ° •/`• FUTURE PHASES �'"' \ a1 5 7. PROPERTY BOUNDARY PROVIDED BY DUKE ENERGY CAROLINAS.
PUMP**
S.ALLBOUNDARIES ARE APPROXIMATE.
9. MAXAR IMAGERY OBTAINED FROM ESRI ONLINE ON MARCH 17, 2022. AERIAL
WAS COLLECTED ON OCTOBER 19, 2021.
�'.
10. DRAWING HAS BEEN SET WITH A PROJECTION OF NORTH CAROLINA STATE
1 / roo GRAPHIC SCALE PLANE COORDINATE SYSTEM FIPS 3200 (NAD83).
DUKE 8Ao zoo o zoo 400 FIGURE 2B
AREA OF FOCUS WATER LEVEL MAP
ENERGY® (IN FEET)
o u CAROLINAS UPPER FLOW ZONE (FEBRUARY 2022)
CLF-304 DRAWN BY: W.PRATER DATE:02/25/2022 GROUNDWATER CONDITIONS QUARTERLY REPORT
798.70 REVISED BY: R. KIEKHAEFER DATE: 04/28/2022
c CHECKED BY: T. COLTON DATE: 04/28/2022 JANUARY 2022 THROUGH MARCH 2O22
APPROVED BY:T. COLTON DATE: 04/28/2022 MARSHALL STEAM STATION
synTerra PROJECT MANAGER: T. rr TERRELL, NORTH CAROLINA
- www.synterracorp.com .com

GWA-04S/D
MW-04/D
0-% 834
4
01-% 853
4
000
0
000
0
G
p
Q 852
Q 833
♦
Z
3
Z
3
LL 851
o
LL 832
O
O
=1
v
O ppDO
C
850
O
♦
2 _
831 O
2 _
O
♦
♦
Ol
_
W
♦
C
W ♦
_
849
830
; ♦
J
1
J
1
L
4) 848
I
�
L
0) 829
tLjiL
I
828
0
847 0
8/1 /2021 10/1 /2021 12/1 /2021 2/1 /2022
8/1 /2021 10/1 /2021 12/1 /2021 2/1 /2022
Date
GWA-04S - Total water level change from transducer installation on 07/30/2021 to 03/31/2022 is -2.8 feet.
MW-04 - Total water level change from transducer installation on 07/30/2021 to 03/31/2022
is -2.9 feet.
GWA-04D - Total water level change from transducer installation on 07/30/2021 to 03/31/2022 is -3.0 feet.
MW-04D - Total water level change from transducer installation on 07/30/2021 to 03/31/2022
is -2.7 feet.
GWA-04S/D
MW-04/D
858
01,14 837
01%
00
00
0000
Q
855
Q
Z
Z 834
LL
LL.
--
C 852
p
%_0
_
♦
171
O
7-0 =
O
♦
C
'
R
�•••----------
—
831
— — — — — — — — — —
>
O O
O
4-07
>
.s
M
W 849
O
0 0
LY
p O O
C
@
fC
O
07 828
L 846
L
07
y
843
825
6/1 /2021 12/1 /2021 6/1 /2022 12/1 /2022
6/1
/2021 12/1 /2021 6/1 /2022 12/1 /2022
Date
LEGEND Notes:
' DUKE
DRAWN BY: D.AVARD DATE:07/21/2021
FIGURE 3A
Cell 5 construction start (05/31/2021) NAVD 88 - North American
ENERGY
REVISED BY: D.AVARD DATE:04/11/2022
BACKGROUND MONTIORING WELL HYDROGRAPHS -
Future Phases 3 through 5 CCR excavation start (06/18/2021) Vertical Datum 1988
CAROLINAS
INDUSTRIAL LANDFILL NO 1.
Cell 5 Blanket Underdrain construction start (9/20/2021) Ft - Feet
CHECKED BY: T. COLTON DATE: 04/11/2022
(1812-INDUS) PHASE 2 EXPANSION
Cell 5 Blanket Underdrain construction completion (10/22/2021)
in -inches
APPROVED BY: DATE:04/11/2022
GROUNDWATER CONDITIONS QUARTERLY REPORT
Shallow Groundwater Flow Zone (Transducer Data)
'
PROJECT MANAGER:T.COLTON
JANUARY 2022 THROUGH MARCH 2O22
Deep Groundwater Flow Zone (Transducer Data) Manual Water Level Measurement
Terra
MARSHALL STEAM STATION
- - - Transient Groundwater Model Water Level Predicted Trend Daily Total Rainfall (inches)
TERRELL, NORTH CAROLINA
www.synterracorp.com

�i
i
MW-07 (OB-3)
820
819
818
817
816
815
814
4
3
C
2
w
C
fY
1
0
8/1 /2021 10/1 /2021 12/1 /2021 2/1 /2022
Date
MW-07 (013-3) - Total water level change from transducer installation on 07/30/2021 to 03/31/2022 is -1.9 feet
MW-07 (OB-3)
822
819
816
813
810
6/1/2021 12/1/2021 Date 6/1/2022 12/1/2022
0-1
00
00
G
Q
Z
4j
LL
C
O
I
R
07
W
07
>
Q)
J
L
846
845
844
843
842
841
840
ILF-02S/D
4
3
C
2
M
C
.M
OG
- 1
0
8/1 /2021 10/1 /2021 12/1 /2021 2/1 /2022
Date
ILF-02S - Total water level change from transducer installation on 07/30/2021 to 03/31/2022 is +0.2 feet.
ILF-02D - Total water level change from transducer installation on 07/30/2021 to 03/31/2022 is +0.7 feet.
ILF-02S/D
849
ONE
1101ME
Mlin
846
O
843
840
837
6/1 /2021
0 0000 0 0 0 ��
0
12/1 /2021 6/1 /2022 12/1 /2022
Date
LEGEND Notes:
' DUKE
DRAWN BY: D.AVARD DATE:07/21/2021
FIGURE 3113
Cell 5 construction start (05/31/2021) NAVD 88 — North American
ENERGY
REVISED BY: D.AVARD DATE:04/11/2022
PERIMETER HYDROGRAPHS — INDUSTRIAL LANDFILL NO 1.
Future Phases 3 through 5 CCR excavation start (06/18/2021) Vertical Datum 1988
CAROLINAS
(1812-INDUS) PHASE 2 EXPANSION
Cell 5 Blanket Underdrain construction start (9/20/2021) Ft- Feet
CHECKED BY: T.COLTON DATE:04/11/2022
GROUNDWATER CONDITIONS QUARTERLY REPORT
Cell 5 Blanket Underdrain construction completion (10/22/2021) in -inches
APPROVED BY: T.COLTON DATE:04/11/2022
JANUARY 2022 THROUGH MARCH 2O22
Shallow Groundwater Flow Zone (Transducer Data)
PROJECT MANAGER: T. COLTON
MARSHALL STEAM STATION
Deep Groundwater Flow Zone (Transducer Data) Manual Water Level Measurement
Terra
TERRELL, NORTH CAROLINA
— — - Transient Groundwater Model Water Level Predicted Trend Daily Total Rainfall (inches)
www.synterracorp.com

CLF21-10
011%
00
843
00
C
Q
842
Z
a-7
W
841
C
O
Z
M
840
07
W
5
839
>
07
J
L
07
838
R
4
3
C
2
N
C
.M
OC
1
0
9/1 /2021 1 1 /1 /2021 1 /1 /2022 3/1 /2022
Date
CLF21-10 - Total water level change from transducer installation on 08/10/2021 to 03/31/2022 is +0.1 feet.
CLF21-10
RAA
0-1
00
00
G
Q
Z
++
W
N
07
W
07
a�
J
L
M
►-
837
843 -
840
837 -
834
6/1 /2021
12/1 /2021 6/1 /2022
Date
0000940-146
0-%
00
00
G
Q
Z
++
W
C
O
I
R
07
W
07
07
J
L
07
�i
i
CLF21-11
830
829
828
827
826
825
824
4
3
C
2
N
C
.M
OC
1
0
9/1 /2021 1 1 /1 /2021 1 /1 /2022 3/1 /2022
Date
— CLF21-11 - Total water level change from transducer installation on 08/09/2021 to 03/31/2022 is -3.2 feet.
CLF21-11
834
831
828 -
825
822
6/1 /2021
12/1 /2021 6/1 /2022
Date
WWAFK19Y>ra
.zo
w
C
Ce
LEGEND Notes:
�' DUKE
DRAWN BY: D.AVARD DATE:07/21/2021
3C
Cell 5 construction start (05/31/2021) NAVD 88 — North American
ENERGY.
REVISED BY: D.AVARD DATE:04/11/2022
NORTHWEST OF CELL 5IGURE
HYDROGRAPHS —INDUSTRIAL
Future phases 3 through 5 CCR excavation start (06/18/2021) Vertical Datum 1988
CAROLINAS
LANDFILL NO 1.
Cell 5 Blanket Underdrain construction start (9/20/2021) Ft - Feet
CHECKED BY: T. COLTON DATE: 04/11/2022
(1812-INDUS) PHASE 2 EXPANSION
6T
Cell 5 Blanket Underdrain construction completion (10/22/2021)
in -inches
APPROVED BY: DATE:04/11/2022
GROUNDWATER CONDITIONS QUARTERLY REPORT
Shallow Groundwater Flow Zone Transducer Data
( )
PROJECT MANAGER: T. COLTON
JANUARY 2022 THROUGH MARCH 2O22 MARSHALL STEAM
— — - Transient Groundwater Model water level predicted trend Manual Water Level Measurement
Terra
STATION
Daily Total Rainfall (inches)
TERRELL, NORTH CAROLINA
www.synterracorp.com

CLF-UD
CLF21-12
0-% 818
00
00
G
Z 816
4j
LL
G 814
Z
N
G7
W 812
>
Q
J
L 810
O
4
3
C
2
M
C
1
0
11 /1 /2021 12/1 /2021 1 /1 /2022 2/1 /2022 3/1 /2022
Date
CLF-UD- Increases in the sump's water levels at times is related to temporary testing of the pump for
optimization of the pump's settings and cycling.
CLF-UD
0.% 819
00
00
G
Q
Z 816
4;
LL
%_0
C
O
R 813
07
W
808
07
>
J 810
L
�1
R
r
807 T-
6/1 /2021
12/1 /2021
Date
6/1 /2022
12/1 /2022
c
M
C
01.
00
00
G
Q
Z
+j
LL
O
M
>
0)
W
0)
>
0)
J
L
M
824
823
822
821
820
819
J14
IV I
.Li
-4
-3
1
818 0
9/1 /2021 11 /1 /2021 1 /1 /2022 3/1 /2022
Date
CLF21-12 - Total water level change from transducer installation on 08/09/2021 to 03/31/2022 is -2.7 feet.
CLF21-12
825 Tr—
*01
815
810
805 '1
6/1 /2021
12/1 /2021 6/1 /2022 12/1 /2022
Date
LEGEND Notes:
�' DUKE
DRAWN BY: D.AVARD DATE:07/21/2021
FIGURE 3D
Cell 5 construction start (05/31/2021) NAVD 88 - North American
ENERGY.
REVISED BY: D.AVARD DATE:04/11/2022
CLF-UD AND SOUTHWEST OF CELL 5 HYDROGRAPHS -
Future phases 3 through 5 CCR excavation start (06/18/2021) Vertical Datum 1988
CAROLINAS
INDUSTRIAL LANDFILL NO 1.
Cell 5 Blanket Underdrain construction start (9/20/2021) Ft - Feet
CHECKED BY: T. COLTON DATE: 04/11/2022
(1812-INDUS) PHASE 2 EXPANSION
6T
Cell 5 Blanket Underdrain construction completion (10/22/2021)
in -inches
APPROVED BY: DATE:04/11/2022
GROUNDWATER CONDITIONS QUARTERLY REPORT
Shallow Groundwater Flow Zone Transducer Data
( )
PROJECT MANAGER: T. COLTON
JANUARY 2022 THROUGH MARCH 2O22 MARSHALL STEAM
- - - Transient Groundwater Model water level predicted trend Manual Water Level Measurement
Terra
STATION
Daily Total Rainfall (inches)
TERRELL, NORTH CAROLINA
www.synterracorp.com

00
00
C
Q
Z
++
LL
O
M
a�
W
07
>
07
J
L
M
►-
823
822
821
820
819
818
817
CLF21-14
LLW
4
3
_
2
M
_
.M
W
1
0
9/1 /2021 1 1 /1 /2021 1 /1 /2022 3/1 /2022
Date
— CLF21-14 - Total water level change from transducer installation on 08/10/2021 to 03/31/2022 is -3.7 feet.
CLF21-14
830
825
820
815
810 T-
6/1 /2021
12/1 /2021 6/1 /2022 12/1 /2022
Date
�i
i
CLF21-15
827
4
826
O
3
825
g
O
O
^
O
=_
824
2
O
823
-1
822
821
0
9/1 /2021 1 1 /1 /2021 1 /1 /2022
3/1 /2022
Date
— CLF21-15
- Total water level change from transducer installation on 08/13/2021 to 03/31/2022 is -3.7 feet.
CLF21-15
828
825
822 -
819
816
6/1 /2021
12/1 /2021 6/1 /2022
Date
WWAFK19Y>ra
LEGEND Notes:
' DUKE
DRAWN BY: D.AVARD DATE:07/21/2021
FIGURE 3E
Cell 5 construction start 05/31/2021 () NAVD 88 - North American
� ENERGY
REVISED BY: D.AVARD DATE:04/11/2022
EAST OF CELL 6 HYDROGRAPHS - INDUSTRIAL LANDFILL
Future phases 3 through 5 CCR excavation start (06/18/2021) Vertical Datum 1988
CAROLINAS
NO 1.
Cell 5 Blanket Underdrain construction start (9/20/2021) Ft - Feet
CHECKED BY: T. COLTON DATE: 04/11/2022
(1812-INDUS) PHASE 2 EXPANSION
6T
Cell 5 Blanket Underdrain construction completion (10/22/2021)
in -inches
APPROVED BY: DATE:04/11/2022
GROUNDWATER CONDITIONS QUARTERLY REPORT
Shallow Groundwater Flow Zone Transducer Data
( )
PROJECT MANAGER: T. COLTON
JANUARY 2022 THROUGH MARCH 2O22 MARSHALL STEAM
- - - Transient Groundwater Model water level predicted trend Manual Water Level Measurement
Terra
STATION
Daily Total Rainfall (inches)
TERRELL, NORTH CAROLINA
www.synterracorp.com

CLF-301
CLF-402
0-4 819
00
00
0
Q 818
Z
LL 817
C
O
816
0l
W
815
0l
J
L
4) 814
4j
N
3
813
-4
-3
1
0
8/1 /2021 10/1 /2021 12/1 /2021 2/1 /2022
Date
CLF-301 - Total water level change from transducer installation on 07/27/2021 to 03/31/2022 is -2.1 feet
CLF-301
819 Tr-
816
813
810
tE
�i
00
0
0
0
0
807
6/1 /2021 12/1 /2021 6/1 /2022 12/1 /2022
Date
LEGEND Notes:
Cell 5 construction start (05/31/2021) NAVD 88 — North American
Future phases 3 through 5 CCR excavation start (06/18/2021) Vertical Datum 1988
Cell 5 Blanket Underdrain construction start (9/20/2021) Ft - Feet
Cell 5 Blanket Underdrain construction completion (10/22/2021) in - Inches
Shallow Groundwater Flow Zone (Transducer Data)
- Transient Groundwater Model water level predicted trend Manual Water Level Measurement
Daily Total Rainfall (inches)
DUKE
ENERGY.
CAROLINAS
,0'
synTerra
0.1% 814
00
00
a
Q 813
Z
LL 812
C
O
m
> 811
07
W
810
07
J
L
W 809
M
00
00
Z
++
LL
C
O
I
N
07
W
07
>
07
J
L
M
4
3
C
2
N
C
.M
W
1
808 0
8/1 /2021 10/1 /2021 12/1 /2021 2/1 /2022
Date
CLF-402 - Total water level change from transducer installation on 07/27/2021 to 03/31/2022 is -2.7 feet.
CLF-402
815
810
805 -
:IG
795
6/1 /2021
DRAWN BY: D. AVARD
REVISED BY: D. AVARD
CHECKED BY: T. COLTON
APPROVED BY: T. COLTON
PROJECT MANAGER: T. COLTON
www.synterracorp.com
00
�
0
IFIR60211YAl
C:�fIP�i➢�►�
11KEFROW14
Date
DATE:07/21/2021 FIGURE 3F
DATE:04/11/2022 FUTURE PHASE III AND IV HYDROGRAPHS — INDUSTRIAL
LANDFILL NO 1.
DATE:04/11/2022 (1812-INDUS) PHASE 2 EXPANSION
DATE:04/11/2022 GROUNDWATER CONDITIONS QUARTERLY REPORT
JANUARY 2022 THROUGH MARCH 2O22 MARSHALL STEAM
STATION
TERRELL, NORTH CAROLINA

CLF21-13/R
CLF-401
00
00
G
Q
Z
4;
LL
>
_O
W
7
>
0)
J
L
M
00
00
G
Q
Z
4;
LL
4-10
O
>
_O
W
O
>
0)
J
L
822
821
820
819
818
817
CLF21-13 was abandoned and
replaced on November 4, 2021.
A ak i AALA10
4
3
2
R
C
1 �
816 0
9/1 /2021 11 /1 /2021 Date 1 /1 /2022 3/1 /2022
CLF21-13R - Total water level change from transducer installation on 11/08/2021 to 03/31/2022 is -0.1 feet.
CLF21-13 - Total water level change from transducer installation on 08/09/2021 to 10/01/2021 is -0.2 feet.
CLF21-13/R
825
820
E:3&'i
810
805 -L+--
6/1 /2021
0
12/1 /2021 6/1 /2022
Date
12/1 /2022
r1-4 818
00
00
ID
Q 817
Z
LL
816
m
> 815
07
W
3
812
iaa
C
4
3
1
0
8/1 /2021 9/1 /2021 10/1 /2021 11 /1 /2021 12/1 /2021 1 /1 /2022 2/1 /2022
Date
CLF-401 - Total water level change from transducer installation on 07/27/2021 to 03/31/2022 is -1.8 feet.
CLF-401
,% 820
00
00
Q 815
Z
LL
= 810
O
M
07
W 805
i
795 T
6/1 /2021
12/1 /2021 6/1 /2022 12/1 /2022
Date
LEGEND Notes:
'DUKE
DRAWN BY: D.AVARD DATE:07/21/2021
FIGURE
Cell 5 construction start (05/31/2021) NAVD 88 - North American
ENERGY.
REVISED BY: D.AVARD DATE:04/11/2022
FUTURE PHASE V HYDROGRAPHSH INDUSTRIAL LANDFILL
Future phases 3 through 5 CCR excavation start (06/18/2021) Vertical Datum 1988
CAROLINAS
NO 1.
Cell 5 Blanket Underdrain construction start (9/20/2021) Ft - Feet
CHECKED BY: T. COLTON DATE: 04/11/2022
(1812-INDUS) PHASE 2 EXPANSION
Cell 5 Blanket Underdrain construction completion (10/22/2021)
in -inches
APPROVED BY: DATE:04/11/2022
GROUNDWATER CONDITIONS QUARTERLY REPORT
Shallow Groundwater Flow Zone Transducer Data
( )
PROJECT MANAGER: T. COLTON
JANUARY 2022 THROUGH MARCH 2O22 MARSHALL STEAM
- Transient Groundwater Model water level predicted trend Manual Water Level Measurement
Terra
STATION
Daily Total Rainfall (inches)
TERRELL, NORTH CAROLINA
www.synterracorp.com

CLF-303
CLF-304
0-0 803
00
0
a 802
Z
4
LL 801
C
O
a=+
800
_O
W
799
>
Q)
J
L
0) 798
M
4
3
C
2
M
C
.M
W
1
797 0
8/1 /2021 10/1 /2021 12/1 /2021 2/1 /2022
Date
CLF-303 - Total water level change from transducer installation on 07/27/2021 to 03/31/2022 is -0.6 feet.
CLF-303
0.% 810
00
00
G
Q
Z 805
4
W
4-0
O
R 800
Q)
W
07
>
J 795
L
►-
790 T -
6/1 /2021
12/1 /2021
6/1 /2022
12/1 /2022
00
00
C
Q
Z
++
W
C
O
M
07
W
07
>
07
J
L
M
801 -
799 -
798 -
797 -
796 -
O
W
-3
C
2
M
C
.M
W
1
795 0
8/1 /2021 10/1 /2021 12/1 /2021 2/1 /2022
Date
CLF-304 - Total water level change from transducer installation on 07/27/2021 to 03/31/2022 is -0.1 feet.
CLF-304
807
804 -
801 -
798 -
795
6/1 /2021
�00
iWaAFKIYA
C:�fIP>"iYx�
iPJAFPZIY414
Date
IDate
LEGEND Notes:
'DUKE
DRAWN BY: D.AVARD DATE:07/21/2021
FIGURE 3G
Cell 5 construction start (05/31/2021) NAVD 88 - North American
ENERGY.
REVISED BY: D.AVARD DATE:04/11/2022
SOUTH OF FUTURE PHASE III HYDROGRAPHS -
Future phases 3 through 5 CCR excavation start (06/18/2021) Vertical Datum 1988
CAROLINAS
INDUSTRIAL LANDFILL NO 1.
Cell 5 Blanket Underdrain construction start (9/20/2021) Ft -Feet
CHECKED BY: T. COLTON DATE: 04/11/2022
(1812-INDUS) PHASE 2 EXPANSION
Cell 5 Blanket Underdrain construction completion (10/22/2021)
in -inches
APPROVED BY: DATE:04/11/2022
GROUNDWATER CONDITIONS QUARTERLY REPORT
Shallow Groundwater Flow Zone Transducer Data
( )
PROJECT MANAGER: T. COLTON
JANUARY 2022 THROUGH MARCH 2O22
- - - Transient Groundwater Model water level predicted trend Manual Water Level Measurement
Terra
MARSHALL STEAM STATION
Daily Total Rainfall (inches)
www.synterracorp.com
TERRELL, NORTH CAROLINA

Z
120
100 ❑
80
60 ■
Cl
20
M
■
�X
❑ Model Flow Rate (gpm)
Rainfall Daily Total (in)
X Actual Pumping Flow Rate (gpm)
Steady State Blanket Underdrain Model Flow
of 18 GPM as presented in Technical Memorandum:
Modeling Support for the ILF Phase 2 Permit to Construct Modifications
O
❑
❑
9/1/2021 3/1/2022 9/1/2022 3/1/2023
(votes: Years of Operation
1. gpm = gallons per minute.
2. Flow data from the first day following a period of no flow were not plotted.
3
vj
U
I& DUKE DRAWN BY: T. COLTON DATE: 10/13/2021 FIGURE 4A
*'ENERGY REVISED BY: K. FERRI DATE: 04/21/2022 CELL 5 (UNDERDRAIN) PUMPING FLOW RATE VS. SIMULATED FLOW RATE
CAROL( - CHECKED BY: T. COLTON DATE: 04/21/2022 GROUNDWATER CONDITIONS QUARTERLY REPORT
APPROVED BY: T. COLTON DATE: 04/21/2022
PROJECT MANAGER: T. COLTON JANUARY 2022 THROUGH MARCH 2O22
MARSHALL STEAM STATION
synTerra www.synterracorp.com TERRELL, NORTH CAROLINA

120
100
80
E
Q
wo
60
ca
DC
_O
'-
40
�o
v
U
20
X
is
0
1
X
►I
E2
X
X Actual Pumping Flow Rate (gpm)
Rainfall Daily Total (in)
9/1/2021 3/1/2022 9/1/2022 3/1/2023
Notes: Years of Operation
1. gpm = gallons per minute.
2. Flow data from the first day following a period of no flow were not plotted.
I' DUKE
DRAWN BY: T. COLTON
DATE: 10/13/2021
FIGURE 4B
*'ENERGY
REVISED BY: K. FERRI
DATE: 04/21/2022
CELL 6 PUMPING FLOW RATE
CAROLI+-
CHECKED BY: T. COLTON
DATE: 04/21/2022
GROUNDWATER CONDITIONS QUARTERLY REPORT
Oft
APPROVED BY: T. COLTON
PROJECT MANAGER: T. COLTON
DATE: 04/21/2022
JANUARY 2022 THROUGH MARCH 2O22
MARSHALL STEAM STATION
synTerra
www.synterracorp.com
TERRELL, NORTH CAROLINA
3
2
KE

CL
wo
a�
c6
O
ILL
Ln
a)
Ln
c6
v
a--+
U-
500
O x
400
300
200
x
x
100
3
❑
2
X Actual Pumping Flow Rate (gpm)
Xx U Model Flow Rate (gpm)
j .� Rainfall Daily Total (in)
0
9/1/2021 3/1/2022 9/1/2022
Notes: Years of Operation
1. gpm = gallons per minute.
2. Flow data from the first day following a period of no flow were not plotted.
3/1/2023
4! 0
9/1/2023
I& DUKE DRAWN BY: T. COLTON DATE: 10/13/2021 FIGURE 4C
*'ENERGY REVISED BY: K. FERRI DATE: 04/21/2022 PHASE III-V PUMPING FLOW RATE VS. SIMULATED FLOW RATE
CAROLI - CHECKED BY: T. COLTON DATE: 04/21/2022 GROUNDWATER CONDITIONS QUARTERLY REPORT
APPROVED BY: T. COLTON DATE: 04/21/2022
PROJECT MANAGER: T. COLTON JANUARY 2022 THROUGH MARCH 2O22
MARSHALL STEAM STATION
synTerra www.synterracorp.com TERRELL, NORTH CAROLINA

Groundwater Conditions Quarterly Report — January 2022 to March 2022
Duke Energy Carolinas, LLC - Marshall Steam Station - Industrial Landfill No. 1
Terrell, North Carolina
TABLES
L7
synTerra
Science & Engineering Consultants

TABLE 1
GROUNDWATER MONITORING NETWORK WELL INFORMATION AND WATER LEVELS
GROUNDWATER CONDITIONS QUARTERLY REPORT
JANUARY 2022 THROUGH MARCH 2O22
MARSHALL STEAM STATION
DUKE ENERGY CAROLINAS, LLC, TERRELL, NC
Well ID
Date Well/
Piezometer
Installed
Date
Transducer
Installed
Monitoring
Zone
Northing
(Ft-NAD 83)
Easting
(Ft-NAD 83)
Measuring Point
TOC Elevation
(Ft-NAVD 88)
Ground Surface
Elevation
(Ft-NAVD 88)
Total Well
2,3
Depth
(Ft-BGS)
Measured
i
Well Depth
(Ft-TOC)
Screened
a
Interval
(Ft TOC)
Top of Screen
Elevation
(Ft-NAVD 88)
Bottom of Screen
Elevation
(Ft-NAVD 88)
Water Level
Measurement
(Ft-TOC)
2/14/2022
Groundwater
Elevation
(Ft-NAVD 88)
2/14/2022
CLF-301
5/21/2021
7/27/2021
Shallow
685838.40
1413513.30
847.46
844.46
62.00
65.00
52.00
62.00
795.46
785.46
32.56
814.90
CLF-303
5/12/2021
7/27/2021
Shallow
684951.10
1413840.30
824.31
822.31
40.00
42.00
30.00
40.00
794.31
784.31
24.90
799.41
CLF-304
5/24/2021
7/27/2021
Shallow
684062.20
1413563.40
823.28
821.28
60.00
62.00
50.00
60.00
773.28
763.28
24.58
798.70
CLF-401
5/17/2021
7/27/2021
Shallow
685783.50
1412779.50
832.44
830.44
39.00
41.00
29.00
39.00
803.44
793.44
18.79
813.65
CLF-402
5/21/2021
7/27/2021
Shallow
685598.80
1413217.80
818.41
816.41
50.00
52.00
40.00
50.00
778.41
768.41
9.23
809.18
CLF21-10
8/6/2021
8/6/2021
Shallow
687020.10
1412353.40
857.75
857.75
32.00
32.00
22.00
32.00
835.75
825.75
17.14
840.61
CLF21-11
8/5/2021
8/5/2021
Shallow
686572.30
1412572.20
848.53
848.53
40.00
40.00
30.00
40.00
818.53
808.53
23.28
825.25
CLF21-12
8/5/2021
8/5/2021
Shallow
686217.40
1412518.20
837.84
835.84
40.00
42.00
30.00
40.00
807.84
797.84
19.32
818.52
CLF21-13R
11/4/2021
11/8/2021
Shallow
686085.92
1412818.66
835.75
835.5
35.00
37.00
25.00
35.00
810.75
800.75
17.77
817.98
CLF21-14
8/10/2021
8/10/2021
Shallow
686027.10
1414268.70
841.56
841.56
36.00
36.00
26.00
36.00
815.56
805.56
23.65
817.91
CLF21-15
8/10/2021
8/10/2021
Shallow
686307.70
1414410.00
864.37
864.37
55.00
55.00
45.00
55.00
819.37
809.37
41.62
822.75
CLF22-305
3/22/2022
Not Installed
Shallow
685228.95
1413445.92
819.21
816.94
16.00
16.00
6.00
16.00
813.21
803.21
Not Installed
Not Installed
CLF22-306
3/22/2022
Not Installed
Shallow
685033.00
1413752.34
816.36
813.57
25.00
25.00
15.00
25.00
801.36
791.36
Not Installed
Not Installed
CLF22-307
3/22/2022
Not Installed
Shallow
684539.89
1413247.50
825.96
823.40
40.00
40.00
30.00
40.00
795.96
785.96
Not Installed
Not Installed
GWA-4D
6/12/2015
7/30/2021
Deep
686783.39
1411776.91
902.45
899.38
90.07
93.14
84.07
89.07
818.38
813.38
53.03
849.42
GWA-4S
5/19/2015
7/30/2021
Shallow
686776.57
1411777.34
901.97
898.98
67.99
70.98
52.19
67.19
849.78
834.78
53.41
848.56
MW-4
6/30/1989
7/30/2021
Shallow
686723.00
1414467.00
866.42
863.75
50.20
52.87
42.87
52.87
823.55
813.55
37.28
829.14
MW-4D
10/12/2006
7/30/2021
Bedrock
686715.00
1414462.00
866.74
863.37
64.18
67.55
58.87
63.87
807.87
802.87
37.40
829.34
MW-7 (013-3)
12/16/2010
7/30/2021
Shallow
685380.10
1414418.00
859.16
856.56
51.40
54.00
39.00
54.00
820.16
805.16
42.74
816.42
ILF-21)
3/31/2019
7/30/2021
Deep
687699.24
1413205.78
885.14
885.57
107.00
106.57
91.57
101.57
793.57
783.57
39.89
845.25
ILF-2S
3/31/2019
1 7/30/2021
1 Shallow
687699.26
1413214.68
884.79
885.21
52.00
51.58
41.58
1 51.58
1 843.21
833.21
42.62
842.17
Notes:
(--) - Data not available
1 Well depths initially measured during well installation and updated as new wells are installed.
Z "Total Well Depth" is the depth to the bottom of the filter pack.
3 Values measured during well installation
BGS - Below ground surface
TOC - Top of casing
Ft - Feet
NA - Not applicable
NAD 83 - North American Datum of 1983
NAVD 88 - North American Vertical Datum of 1988
NM - Not measured
Prepared by: GTC Checked by: DAA
Page 1 of 1

TABLE 2
SITE -WIDE WATER LEVEL ELEVATION DATA TABLE
GROUNDWATER CONDITIONS QUARTERLY REPORT
JANUARY 2022 THROUGH MARCH 2O22
MARSHALL STEAM STATION
DUKE ENERGY CAROLINAS, LLC, TERRELL, NC
Well ID
Ground Surface Elevation
(Ft -NAND 88)
TOC Elevation
(Ft -NAND 88)
Quarter 12022
Monitoring
Zone
Water Level
Measurement
(Ft-TOC)
2/14/2021
Groundwater
Elevation
(Ft-NAVD 88)
2/14/2021
Groundwater Monitoring Wells
Within the Area of Interest
CLF-301
844.46
847.46
32.56
814.90
Shallow
CLF-302
830.1
832.10
Abandoned
Abandoned
Shallow
CLF-303
822.31
824.31
24.90
799.41
Shallow
CLF-304
821.28
823.28
24.58
798.70
Shallow
CLF-401
830.44
832.44
18.79
813.65
Shallow
CLF-402
816.41
818.41
9.23
809.18
Shallow
CLF-403
824.39
826.39
Abandoned
Abandoned
Shallow
CLF-404
826.14
828.14
Abandoned
Abandoned
Shallow
CLF21-10
857.75
857.75
17.14
840.61
Shallow
CLF21-11
848.53
848.53
23.28
825.25
Shallow
CLF21-12
835.84
837.84
19.32
818.52
Shallow
CLF21-13
827.76
836.76
Abandoned
Abandoned
Shallow
CLF21-13R
835.5
835.75
17.77
817.98
Shallow
CLF21-14
841.56
841.56
23.65
817.91
Shallow
CLF21-15
864.37
864.37
41.62
822.75
Shallow
CLF21-16
830.35
830.85
Abandoned
Abandoned
Shallow
CLF21-17
830.76
830.76
Abandoned
Abandoned
Shallow
CLF21-18
831.92
834.79
Abandoned
Abandoned
Shallow
CLF21-19
830.48
827.73
Abandoned
Abandoned
Shallow
CLF21-20
828.43
831.55
Abandoned
Abandoned
Shallow
GWA-41D
899.38
902.45
53.03
849.42
Deep
GWA-4S
898.98
901.97
53.41
848.56
Shallow
I LF-2D
885.57
885.14
39.89
845.25
Deep
ILF-2S
885.21
884.79
42.62
842.17
Shallow
M W-4
864.5
867.15
37.28
829.87
Shallow
MW-41D
863.37
866.74
37.40
829.34
Bedrock
MW-7 (013-3)
856.56
859.16
42.74
816.42
Shallow
Groundwater Monitoring Wells
Beyond the Area of Interest
AB-10BR
799.53
802.54
18.49
784.05
Bedrock
AB-10BRL
799.34
801.59
10.66
790.93
Bedrock
AB-10D
799.58
802.68
19.39
783.29
Bedrock
AB-10S
799.54
802.41
17.51
784.90
Shallow
AB-10SL
799.52
802.52
18.76
783.76
Shallow
AB-12BR
792.59
795.43
No Access
No Access
Bedrock
AB-12D
792.56
795.45
No Access
No Access
Bedrock
AB-12S
792.7
795.61
No Access
No Access
Shallow
AB-12SL
792.7
795.67
No Access
No Access
Shallow
AB-13D
821.59
824.55
25.82
798.73
Bedrock
AB-13S
821.21
823.73
24.70
799.03
Shallow
AB-14D
821.45
824.11
11.91
812.20
Deep
AB-14DU
822.01
824.83
11.94
812.89
Shallow
AB-14S
821.73
824.71
12.76
811.95
Shallow
AB-15BR
820.04
823.01
Abandoned
Abandoned
Bedrock
AB-15D
820.26
823.04
Abandoned
Abandoned
Bedrock
AB-15S
820.14
823.27
Abandoned
Abandoned
Shallow
AB-15SL
820.02
823.17
Abandoned
Abandoned
Shallow
AB-1BR
774.93
775.24
9.90
765.34
Bedrock
AB-1BRL
774.77
774.78
9.20
765.58
Bedrock
AB-1BRLL
774.79
774.54
8.93
765.61
Bedrock
AB-1BRLLL
775.7
775.45
9.02
766.43
Bedrock
AB-11D
774.93
774.76
10.82
763.94
Deep
AB-1S
774.75
774.53
12.35
762.18
Shallow
AB-21D
807.61
810.23
24.90
785.33
Deep
AB-21S
807.95
810.66
25.97
784.69
Shallow
AB-2BR
778.13
781.06
0.00
781.06
Bedrock
AB-21D
778.48
781.44
18.04
763.40
Deep
AB-2S
778.58
781.30
21.95
759.35
Shallow
AB-31D
812.14
815.03
31.20
783.83
Bedrock
AB-3S
812
815.08
Dry
Dry
Shallow
AB-41D
807.17
810.01
29.72
780.29
Deep
AB-4S
807.43
809.73
23.23
786.50
Shallow
AB-4SL
807.34
809.85
24.49
785.36
Shallow
AB-5BR
804.45
807.55
12.72
794.83
Bedrock
Page 1 of 4

TABLE 2
SITE -WIDE WATER LEVEL ELEVATION DATA TABLE
GROUNDWATER CONDITIONS QUARTERLY REPORT
JANUARY 2022 THROUGH MARCH 2O22
MARSHALL STEAM STATION
DUKE ENERGY CAROLINAS, LLC, TERRELL, NC
Well ID
Ground Surface Elevation
(Ft -NAND 88)
TOC Elevation
(Ft -NAND 88)
Quarter 12022
Monitoring
Zone
Water Level
Measurement
(Ft-TOC)
2/14/2021
Groundwater
Elevation
(Ft-NAVD 88)
2/14/2021
Groundwater Monitoring Wells Beyond the Area of Interest (Continued)
AB-5 D
804.47
807.52
11.79
795.73
Deep
AB-5DU
804.92
807.58
11.66
795.92
Shallow
AB-5S
804.56
807.50
12.11
795.39
Shallow
AB-6BRA
833.77
836.70
Abandoned
Abandoned
Bedrock
AB-6BRL
834.14
836.76
Abandoned
Abandoned
Bedrock
AB-6D
832.9
835.36
Abandoned
Abandoned
Bedrock
AB-6S
832.77
835.38
Abandoned
Abandoned
Shallow
AB-7D
831.21
834.13
Abandoned
Abandoned
Deep
AB-7DU
831.62
834.08
Abandoned
Abandoned
Shallow
AB-7S
831.43
834.29
Abandoned
Abandoned
Shallow
AB-81D
797.50
800.50
8.88
791.62
Bedrock
AB-8DU
797.53
800.38
8.70
791.68
Shallow
AB-8S
797.42
800.33
8.13
792.20
Shallow
AB-9BR
794.94
797.64
13.15
784.49
Bedrock
AB-91D
794.76
797.26
13.60
783.66
Bedrock
AB-9S
795.38
797.78
14.39
783.39
Shallow
AL-1BR
815.02
818.07
81.72
736.35
Bedrock
AL-1BRL
815.41
813.29
53.70
759.59
Bedrock
AL-1D
815.05
817.94
79.35
738.59
Bedrock
AL-1S
814.93
817.97
Dry
Dry
Shallow
AL-2BR
912.78
915.10
108.97
806.13
Bedrock
AL-2BRL
912.67
915.39
116.50
798.89
Bedrock
AL-2BRLL
911.77
914.63
117.02
797.61
Bedrock
AL-2BRLLL
913.01
915.81
118.21
797.60
Bedrock
AL-2D
912.83
915.33
110.91
804.42
Deep
AL-2S
912.53
915.41
112.51
802.90
Shallow
AL-3BR
916.03
919.02
113.52
805.50
Bedrock
AL-3D
915.99
918.69
111.12
807.57
Deep
AL-3S
915.77
918.59
109.64
808.95
Shallow
AL-4BR
915.75
918.72
106.14
812.58
Bedrock
AL-4BRL
915.84
918.74
121.02
797.72
Bedrock
AL-4D
916.01
918.44
101.70
816.74
Deep
BG-1BRA
814.23
817.24
14.84
802.40
Bedrock
BG-1D
814.75
817.63
10.89
806.74
Deep
BG-1S
814.79
817.35
5.88
811.47
Shallow
BG-2BR
811.99
814.81
6.41
808.40
Bedrock
BG-2S
811.82
814.33
4.79
809.54
Shallow
BG-3BR
864.72
867.68
37.62
830.06
Bedrock
BG-3 D
861.56
864.18
29.53
834.65
Deep
BG-3S
860.75
863.03
30.10
832.93
Deep
CCR-15D
802.42
805.14
17.05
788.09
Shallow
CCR-15S
802.24
804.76
BTP
BTP
Shallow
CCR-16D
816.42
819.37
24.40
794.97
Deep
CCR-16S
816.15
819.32
BTP
BTP
Shallow
CCR-11D
807.42
809.32
11.83
797.49
Deep
CCR-1S
807.34
810.31
18.96
791.35
Shallow
CCR-21D
804.12
806.89
23.72
783.17
Deep
CCR-2S
804.24
806.56
23.54
783.02
Shallow
CCR-3 D
777.1
780.44
23.23
757.21
Deep
CCR-3S
777.39
780.28
23.64
756.64
Shallow
CCR-41D
780.94
783.82
24.96
758.86
Deep
CCR-4S
780.85
783.66
25.61
758.05
Shallow
CCR-51D
774.24
776.97
17.32
759.65
Deep
CCR-5S
774.23
777.25
18.96
758.29
Shallow
CCR-9DA
796.84
799.77
36.83
762.94
Deep
CCR-9S
796.91
799.88
38.85
761.03
Shallow
CP-1BR
803.45
806.32
23.82
782.50
Bedrock
CP-1D
803.66
806.40
24.12
782.28
Deep
CP-1S
803.47
806.32
BTP
BTP
Shallow
CP-2D
807.95
810.83
16.81
794.02
Deep
CP-2S
807.79
810.67
16.55
794.12
Shallow
CP-3D
807.69
810.58
18.27
792.31
Deep
CP-3S
807.81
810.47
BTP
BTP
Shallow
Page 2 of 4

TABLE 2
SITE -WIDE WATER LEVEL ELEVATION DATA TABLE
GROUNDWATER CONDITIONS QUARTERLY REPORT
JANUARY 2022 THROUGH MARCH 2O22
MARSHALL STEAM STATION
DUKE ENERGY CAROLINAS, LLC, TERRELL, NC
Well ID
Ground Surface Elevation
(Ft -NAND 88)
TOC Elevation
(Ft -NAND 88)
Quarter 12022
Monitoring
Zone
Water Level
Measurement
(Ft-TOC)
2/14/2021
Groundwater
Elevation
(Ft-NAVD 88)
2/14/2021
Groundwater Monitoring Wells Beyond the Area of Interest (Continued)
GP-1D
855
858.03
57.52
800.51
Deep
GP-1S
855.13
858.13
57.72
800.41
Shallow
GP-2D
830.73
833.68
29.78
803.90
Deep
GP-2S
830.52
833.45
29.30
804.15
Shallow
GP-3D
853.53
856.46
53.87
802.59
Deep
GP-3S
853.46
856.39
53.80
802.59
Shallow
GWA-10D
775.27
778.10
29.65
748.45
Deep
GWA-10S
775.32
777.65
Dry
Dry
Shallow
GWA-11BR
807
810.03
85.00
725.03
Bedrock
GWA-11D
808.24
811.24
83.43
727.81
Deep
GWA-11S
809.59
812.55
BTP
BTP
Shallow
GWA-12BR
876.02
875.65
19.08
856.57
Bedrock
GWA-12D
876.29
875.83
17.28
858.55
Bedrock
GWA-12S
888.01
887.87
17.50
870.37
Shallow
GWA-13DA
888.14
888.28
24.97
863.31
Deep
GWA-13S
888.01
887.87
20.24
867.63
Shallow
GWA-14D
911.48
911.41
40.64
870.77
Deep
GWA-14S
911.24
910.69
39.72
870.97
Shallow
GWA-15D
778.96
781.85
32.56
749.29
Deep
GWA-15S
778.53
781.39
32.05
749.34
Shallow
GWA-1BR
803.15
806.10
43.45
762.65
Bedrock
GWA-1D
803.27
806.05
45.67
760.38
Deep
GWA-IS
803.16
805.97
46.54
759.43
Shallow
GWA-2DA
823.79
826.59
25.64
800.95
Deep
GWA-2S
823.91
826.97
25.33
801.64
Shallow
GWA-3D
836.48
839.44
2.58
836.86
Deep
GWA-3S
836.42
839.24
2.41
836.83
Shallow
GWA-5D
844.36
847.17
34.35
812.82
Deep
GWA-5S
844.3
847.22
BTP
BTP
Shallow
GWA-6D
843.32
845.72
38.25
807.47
Bedrock
GWA-6S
842.99
845.37
37.87
807.50
Shallow
GWA-7D
809.55
812.50
9.07
803.43
Deep
GWA-7S
807.8
810.72
11.45
799.27
Shallow
GWA-8D
850.59
853.68
32.32
821.36
Bedrock
GWA-8S
849.75
852.90
29.93
822.97
Shallow
GWA-9BR
845.53
848.45
0.00
848.45
Bedrock
MS-10
848.29
851.29
17.85
833.44
Shallow
MS-11
856.87
859.78
34.34
825.44
Shallow
MS-12
832.7
835.66
23.20
812.46
Shallow
MS-13
839.19
841.90
30.85
811.05
Shallow
MS-14
841.27
844.07
36.29
807.78
Shallow
MS-15
858.42
861.47
42.92
818.55
Shallow
MS-16
834.25
836.98
25.70
811.28
Deep
MS-8
869.35
872.34
42.97
829.37
Shallow
MS-9
865.36
868.04
40.62
827.42
Shallow
M W-1
821.2
823.70
BTP
BTP
Shallow
MW-10D
770
772.04
16.29
755.75
Deep
M W-10S
769.74
772.05
16.32
755.73
Shallow
M W-11D
881.95
884.67
42.51
842.16
Deep
M W-11S
882.01
884.99
42.86
842.13
Shallow
M W-12D
869.01
871.88
17.02
854.86
Deep
MW-12S
869.02
871.86
15.66
856.20
Deep
M W-13D
844.44
847.05
0.39
846.66
Deep
M W-13S
844.9
847.49
1.99
845.50
Shallow
M W-14BR
807.65
810.49
49.14
761.35
Bedrock
MW-14BRL
809.05
811.77
41.08
770.69
Bedrock
MW-14D
808.67
811.43
45.88
765.55
Deep
MW-14S
808.23
811.29
Below Pump
BTP
Shallow
M W-2
794.9
797.21
11.28
785.93
Shallow
M W-3
811
813.07
7.10
805.97
Shallow
MW-61D
788.15
791.19
27.39
763.80
Deep
MW-6S
787.46
790.35
Dry
Dry
Shallow
MW-7D
772.9
776.85
12.96
763.89
Deep
Page 3 of 4

TABLE 2
SITE -WIDE WATER LEVEL ELEVATION DATA TABLE
GROUNDWATER CONDITIONS QUARTERLY REPORT
JANUARY 2022 THROUGH MARCH 2O22
MARSHALL STEAM STATION
DUKE ENERGY CAROLINAS, LLC, TERRELL, NC
Well ID
Ground Surface Elevation
(Ft -NAND 88)
TOC Elevation
(Ft -NAND 88)
Quarter 12022
Monitoring
Zone
Water Level
Measurement
(Ft-TOC)
2/14/2021
Groundwater
Elevation
(Ft-NAVD 88)
2/14/2021
Groundwater Monitoring Wells Beyond the Area of Interest (Continued)
MW-7S
773.1
775.99
Dry
Dry
Shallow
MW-81D
771.34
775.18
16.77
758.41
Bedrock
MW-8S
771.54
775.34
18.39
756.95
Shallow
MW-91D
774.34
777.38
19.75
757.63
Deep
MW-9S
774.22
777.34
19.50
757.84
Shallow
OB-1(CAMA)
847.59
825.85
Abandoned
Abandoned
Shallow
PVSF-1BR
877.36
880.17
52.50
827.67
Bedrock
PVSF-1D
877.55
880.28
49.63
830.65
Deep
PVSF-IS
877.62
880.27
48.93
831.34
Shallow
PVSF-2BR
830.48
833.36
Abandoned
Abandoned
Bedrock
PVSF-2BRL
830.03
832.84
Abandoned
Abandoned
Bedrock
PVSF-2D
830.44
833.20
Abandoned
Abandoned
Deep
PVSF-2S
830.44
833.15
Abandoned
Abandoned
Shallow
PVSF-3BR
835.38
838.22
Abandoned
Abandoned
Bedrock
PVSF-3D
835.44
838.02
Abandoned
Abandoned
Deep
PVSF-3S
835.17
838.18
Abandoned
Abandoned
Shallow
PVSF-4BR
858.66
858.45
12.41
846.04
Bedrock
PVSF-4D
858.78
858.58
10.68
847.90
Deep
PVSF-4S
858.74
858.57
9.91
848.66
Shallow
Notes:
1 Artesian conditions present
TOC - Below Top of Casing
BTP - Water Level below top of pump
Dry - Groundwater not measurable within well screen or riser at time of gauging event
Ft - feet
NAVD 88 - North American Vertical Datum of 1988.
NM - Not measured/available
Prepared by: GTC Checked by: DAA
Page 4 of 4

Groundwater Conditions Quarterly Report —January 2022 to March 2022
Duke Energy Carolinas, LLC - Marshall Steam Station - Industrial Landfill No. 1
Terrell, North Carolina
APPENDIX A
WATER LEVEL MONITORING DATA FILES
INCLUDED AS EXCEL FILE)
L7
synTerra
Science & Engineering Consultants

Groundwater Conditions Quarterly Report —January 2022 to March 2022
Duke Energy Carolinas, LLC - Marshall Steam Station - Industrial Landfill No. 1
Terrell, North Carolina
APPENDIX 6
GROUNDWATER MODEL PREDICTED TREND FILES
INCLUDED AS EXCEL FILE)
L7
synTerra
Science & Engineering Consultants

Groundwater Conditions Quarterly Report —January 2022 to March 2022
Duke Energy Carolinas, LLC - Marshall Steam Station - Industrial Landfill No. 1
Terrell, North Carolina
APPENDIX C
DEWATERING/UNDERDRAIN PUMPING DATA FILES
INCLUDED AS EXCEL FILE)
L7
synTerra
Science & Engineering Consultants