3619_DukeAllen_NSLF_GWInfo_FID1755961_20221216

DUKE
ENERGY
December 16, 2022
North Carolina Department of Environmental Quality
Division of Waste Management
Solid Waste Section
2090 U.S. 70 Highway
Swannanoa, NC 28778-8211
Attn: Ms. Sarah Moutos
526 S. Church Street
EC13K
Charlotte, NC 28202
Re: Groundwater Information to Demonstrate Vertical Separation REQUEST FOR APPROVAL— North Starter
Landfill
Reference No.: 3619-INDUS
Allen Steam Station
Gaston County, North Carolina
Dear Ms. Moutos,
In order to stay on track with the overall ash basin closure schedule, and in light of significant rainfall received at
the Allen Steam Station (Allen) site throughout the month of November 2022 and thus far in December 2022,
Duke Energy Carolinas, LLC (Duke Energy) has decided to revise the North Starter Landfill (NSLF) base grades.
The proposed revisions are detailed in a companion submittal as a Permit to Construct (PTC) Modification
Request submitted concurrently under separate cover to Mr. Jordan Russ of the North Carolina Department of
Environmental Quality Division of Waste Management, Solid Waste Section (Section). The proposed revisions to the
NSLF base grades are minor and primarily in the location of the leachate collection sump and southeastern corner of
the NSLF. No change in horizontal limits of the NSLF are proposed. The groundwater information provided herein is
intended to supplement the PTC Modification Request to relocate the NSLF sump.
Table 1 of this submittal includes a summary of water level measurements for the NSLF footprint and
surrounding vicinity from October 29, 2021 through December 9, 2022. The last page of Table 1 denotes the
"target elevation" for groundwater surface (5-feet below top of CSL elevation; 4-feet below the bottom of the
liner system), as well as, the variance between target elevation and most recent groundwater elevation at
piezometers located within the footprint of the NSLF. Note that only the target elevations for NSLF-PZ-04 and
NSLF-PZ-05 were affected by the proposed revisions to the NSLF base grades. The target elevations included in
Table 1 and Figure 1 of this submittal represent those applicable to the revised NSLF base grades per the
companion submittal mentioned above. Figure 1 includes hydrographs depicting precipitation and groundwater
elevation trends at select shallow wells and piezometers in and around the NSLF.
As indicated by Table 1 and Figure 1, the piezometers located within the NSLF footprint (NSLF-PZ-01, NSLF-PZ-
02, NSLF-PZ-04, and NSLF-PZ-05) have achieved their respective target groundwater elevations.
• NSLF-PZ-01 achieved and has continued to meet its target elevation since prior to water level
measurements collected as part of this scope, so prior to October 29, 2021.
Page 1 of 2

Groundwater Information to Demonstrate Vertical Separation
Allen Steam Station — NSLF 3619-INDUS December 16, 2022
• NSLF-PZ-02 achieved and has continued to meet its target elevation since the April 1, 2022 water level
measurement.
NSLF-PZ-04 achieved and has continued to meet its target elevation (per revised NSLF sump location)
since the July 8, 2022 water level measurement.
• NSLF-PZ-05 achieved and has continued to meet its target elevation (per revised NSLF sump location)
since the September 28, 2022 water level measurement.
Upon the Section's review of the enclosed information, Duke Energy respectfully requests approval to
continue construction, including components of the liner system for the Allen NSLF and abandon NSLF-PZ-04
and NSLF-PZ-05 once CSL placement progression warrants such.
If you have any questions or comments regarding this submittal, please contact me at Courtney.Murphy@duke-
energy.com or [phone].
Respectfully submitted,
Courtney W. Murphy, P.G.
Environmental Services
Enclosures (2): Table 1— Groundwater Elevations —Allen Steam Station — NSLF
Figure 1— Allen Steam Station — NSLF Select Well/Piezometer Hydrographs
Cc: Jordan Russ — NCDEQ
Claire Osborn — NCDEQ
Ed Sullivan — Duke Energy
Tyler Hardin — Duke Energy
Kim Witt — Duke Energy
Kyle Baucom — Duke Energy
Henry Duperier — Duke Energy
Jay Mokotoff—AECOM
Chris Suttell - SynTerra
Page 2 of 2

TABLE 1 - GROUNDWATER ELEVATIONS
ALLEN STEAM STATION - NSLF
Well ID
Location Description Relative to NSLF
Monitoring
Flow
Zone
Top of Well
Casing
(ft-NAVD 88)*
Screened
Interval
(Ft-BGS)
10/29/2021
11/5/2021
11/11/2021
11/18/2021
Depth to
Water
(Ft BTOC)
Groundwater
Elevation
(Ft-NAVD 88)
Depth to
Water
(Ft-BTOC)
Groundwater
Elevation
(Ft-NAVD 88)
Depth
(Ft-BTOC) Water
Groundwater
Elevation
(Ft-NAVD 88)
Water
Depth (Ft-BTOC)
Groundwater
Elevation
(Ft-NAVD 88)
NSLF-PZ-01
Within NSLF Footprint - North End
Shallow
631.11
3.00
13.00
9.95
621.16
10.30
620.81
10.61
620.50
10.73
620.38
NSLF-PZ-02
Within NSLF Footprint - Central
Shallow
626.76
3.00
13.00
5.40
621.36
6.35
620.41
6.95
619.81
7.22
619.54
NSLF-PZ-03
East of central NSLF in RAB
Shallow
640.47
13.00
38.00
20.89
619.58
21.17
619.30
21.43
619.04
21.70
618.77
NSLF-PZ-04
Within NSLF footprint -135' Northeast of sump
Shallow
624.57
10.00
20.00
6.55
618.02
7.08
617.49
7.81
616.76
8.05
616.52
NSLF-PZ-05
Within Revised NSLF Sump Area
Shallow
614.13
5.00
20.00
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
AB-1R
Northwest of NSLF outside RAB
Shallow
675.86
51.00
71.00
49.32
626.54
49.80
626.06
49.97
625.89
49.93
625.93
AB-2
South of NSLF just outside RAB
Shallow
638.74
4.00
19.00
21.83
616.91
22.04
616.70
BTP
BTP
22.05
616.69
AB-2D
South of NSLF just outside RAB
Deep
638.33
65.00
70.00
NM
NM
22.65
615.68
23.40
614.93
24.10
614.23
AB-34S
East of central NSLF in RAB
Shallow
632.88
20.00
35.00
NM
NM
21.18
611.70
21.31
611.57
21.42
611.46
AB-34D
East of central NSLF in RAB
Deep
632.93
138.00
143.00
NM
NM
22.20
610.73
22.27
610.66
22.43
610.50
AB-35D
East of NSLF in DORS
Deep
664.55
116.00
121.00
NM
NM
46.24
618.31
46.38
618.17
46.60
617.95
AB-35S
East of NSLF in DORS
Ash Pore Water
664.47
35.00
50.00
NM
NM
45.94
618.53
46.05
618.42
46.15
618.32
AB-35PWS
East of NSLF in DORS
Shallow
663.47
89.00
99.00
45.32
618.15
45.59
617.88
45.80
617.67
45.98
617.49
AB-39D
East of NSLF in DORS
Deep
637.46
83.00
88.00
NM
NM
19.58
617.88
19.74
617.72
19.92
617.54
AB-39S
East of NSLF in DORS
Ash Pore Water
637.47
30.00
45.00
19.60
617.87
19.89
617.58
20.00
617.47
20.20
617.27
CCR-BG-IDA
West of NSLF outside RAB
Deep
661.17
122.38
127.38
NM
NM
32.28
628.89
32.37
628.80
32.55
628.62
CCR-BG-1S
West of NSLF outside RAB
Shallow
660.37
39.98
54.98
32.55
627.82
32.90
627.47
BTP
BTP
33.23
627.14
GWA-15D
Southwest of NSLF outside RAB
Deep
633.27
84.50
89.50
NM
NM
9.22
624.05
9.35
623.92
9.40
623.87
GWA-15S
Southwest of NSLF outside RAB
Shallow
632.71
17.00
32.00
8.21
624.50
8.52
624.19
8.63
624.08
8.69
624.02
Notes:
Summary table originally developed by SynTerra and modified by Duke Energy for this submittal.
negative variance between top of CSL elevation and most recent water level elevation; denotes water level meets vertical separation criteria
= positive variance between top of CSL elevation and most recent water level elevation; denotes water level still needs to decrease by respective value to meet vertical separation criteria
*Top of PVC well casing for NSLF-PZ-04 was cut down to 616.54 in mid -April 2022
^ - target elevation for a minimum of 5 feet of vertical separation from future top of CSL based on revised NSLF sump location (see AECOM PTC Modification Request dated 12/14/2022)
NSLF-PZ-01 through NSLF-PZ-04 installed October 2021. NSLF-PZ-05 installed August 2022. Other well locations shown were previously installed under CAMA and/or CCR programs.
BTP - well is fitted with a dedicated bladder pump and water level occurs below top of the pump, preventing a water level measurement without disturbing the water column.
BGS - below ground surface
BTOC - below top of casing
CSL - compacted soil liner
DORS - distribution of residual solids
Dry - well was dry at time of water level sweep.
Ft - feet
N/A - not applicable
NA - not available
NAVD 88 - North American Vertical Datum of 1988.
NM - not measured
RAB - retired ash basin
Page 1 of 14

TABLE 1 - GROUNDWATER ELEVATIONS
ALLEN STEAM STATION - NSLF
Well ID
Location Description Relative to NSLF
Monitoring
Flow
Zone
Top of Well
Casing
(ft-NAVD 88)*
Screened
Interval
(Ft-BGS)
12/02/2021
12/08/2021
12/16/2021
Depth Water
(Ft-BTOC)
Groundwater
Elevation
(Ft-NAVD 88)
Depth (Ft-BTOC) to Water
Groundwater
Elevation
(Ft-NAVD 88)
Depth (Ft-BTOC) to Water
Groundwater
Elevation
(Ft-NAVD 88)
NSLF-PZ-01
Within NSLF Footprint - North End
Shallow
631.11
3.00
13.00
11.18
619.93
11.30
619.81
11.05
620.06
NSLF-PZ-02
Within NSLF Footprint - Central
Shallow
626.76
3.00
13.00
7.88
618.88
7.30
619.46
7.49
619.27
NSLF-PZ-03
East of central NSLF in RAB
Shallow
640.47
13.00
38.00
22.26
618.21
22.47
618.00
22.75
617.72
NSLF-PZ-04
Within NSLF footprint -135' Northeast of sump
Shallow
624.57
10.00
20.00
8.81
615.76
8.97
615.60
9.23
615.34
NSLF-PZ-05
Within Revised NSLF Sump Area
Shallow
614.13
5.00
20.00
N/A
N/A
N/A
N/A
N/A
N/A
AB-1R
Northwest of NSLF outside RAB
Shallow
675.86
51.00
71.00
50.15
625.71
50.55
625.31
50.38
625.48
AB-2
South of NSLF just outside RAB
Shallow
638.74
4.00
19.00
NM
NM
22.05
616.69
22.05
616.69
AB-2D
South of NSLF just outside RAB
Deep
638.33
65.00
70.00
24.63
613.70
24.66
613.67
25.07
613.26
AB-34S
East of central NSLF in RAB
Shallow
632.88
20.00
35.00
21.68
611.20
21.90
610.98
21.91
610.97
AB-34D
East of central NSLF in RAB
Deep
632.93
138.00
143.00
22.64
610.29
22.88
610.05
22.88
610.05
AB-35D
East of NSLF in DORS
Deep
664.55
116.00
121.00
46.98
617.57
46.92
617.63
47.21
617.34
AB-35S
East of NSLF in DORS
Ash Pore Water
664.47
35.00
50.00
46.52
617.95
46.44
618.03
46.61
617.86
AB-35PWS
East of NSLF in DORS
Shallow
663.47
89.00
99.00
46.33
617.14
46.41
617.06
46.65
616.82
AB-39D
East of NSLF in DORS
Deep
637.46
83.00
88.00
20.36
617.10
20.50
616.96
20.65
616.81
AB-39S
East of NSLF in DORS
Ash Pore Water
637.47
30.00
45.00
20.62
616.85
20.75
616.72
20.92
616.55
CCR-BG-IDA
West of NSLF outside RAB
Deep
661.17
122.38
127.38
32.94
628.23
33.00
628.17
33.14
628.03
CCR-BG-1S
West of NSLF outside RAB
Shallow
660.37
39.98
1 54.98
1 33.67
626.70
33.80
626.57
34.33
626.04
GWA-15D
Southwest of NSLF outside RAB
Deep
633.27
84.50
89.50
NM
NM
9.55
623.72
9.61
623.66
GWA-15S
Southwest of NSLF outside RAB
Shallow
632.71
17.00
32.00
NM
NM
8.85
623.86
8.90
623.81
Notes:
Summary table originally developed by SynTerra and modified by Duke Energy for this submittal.
negative variance between top of CSL elevation and most recent water level elevation; denotes water level meets vertical separation criteria
= positive variance between top of CSL elevation and most recent water level elevation; denotes water level still needs to decrease by respective value to meet vertical separation criteria
*Top of PVC well casing for NSLF-PZ-04 was cut down to 616.54 in mid -April 2022
^ - target elevation for a minimum of 5 feet of vertical separation from future top of CSL based on revised NSLF sump location (see AECOM PTC Modification Request dated 12/14/2022)
NSLF-PZ-01 through NSLF-PZ-04 installed October 2021. NSLF-PZ-05 installed August 2022. Other well locations shown were previously installed under CAMA and/or CCR programs.
BTP - well is fitted with a dedicated bladder pump and water level occurs below top of the pump, preventing a water level measurement without disturbing the water column.
BGS - below ground surface
BTOC - below top of casing
CSL - compacted soil liner
DORS - distribution of residual solids
Dry - well was dry at time of water level sweep.
Ft - feet
N/A - not applicable
NA - not available
NAVD 88 - North American Vertical Datum of 1988.
NM - not measured
RAB - retired ash basin
Page 2 of 14

TABLE 1 - GROUNDWATER ELEVATIONS
ALLEN STEAM STATION - NSLF
Well ID
Location Description Relative to NSLF
Monitoring
Flow
Zone
Top of Well
Casing
(ft-NAVD 88)*
Screened
Interval
(Ft-BGS)
12/28/2021
01/07/2022
01/14/2022
01/27/2022
Depth to Water
(Ft-BTOC)
Groundwater
Elevation
(Ft-NAVD 88)
Depth to Water
(Ft-BTOC)
Groundwater
Elevation
(Ft-NAVD 88)
Depth to Water
(Ft-BTOC)
Groundwater
Elevation
(Ft-NAVD 88)
Depth to Water
(Ft-BTOC)
Groundwater
Elevation
(Ft-NAVD 88)
NSLF-PZ-01
Within NSLF Footprint - North End
Shallow
631.11
3.00
13.00
10.83
620.28
10.23
620.88
10.55
620.56
9.97
621.14
NSLF-PZ-02
Within NSLF Footprint - Central
Shallow
626.76
3.00
13.00
7.34
619.42
6.35
620.41
7.19
619.57
6.51
620.25
NSLF-PZ-03
East of central NSLF in RAB
Shallow
640.47
13.00
38.00
23.03
617.44
22.94
617.53
23.19
617.28
23.12
617.35
NSLF-PZ-04
Within NSLF footprint -135' Northeast of sump
Shallow
624.57
10.00
20.00
9.39
615.18
9.78
614.79
9.62
614.95
9.83
614.74
NSLF-PZ-05
Within Revised NSLF Sump Area
Shallow
614.13
5.00
20.00
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
AB-1R
Northwest of NSLF outside RAB
Shallow
675.86
51.00
71.00
50.62
625.24
50.90
624.96
50.76
625.10
51.14
624.72
A13-2
South of NSLF just outside RAB
Shallow
638.74
4.00
19.00
21.96
616.78
22.06
616.68
22.18
616.56
Dry
Dry
AB-2D
South of NSLF just outside RAB
Deep
638.33
65.00
70.00
25.35
612.98
25.07
613.26
25.60
612.73
25.45
612.88
AB-34S
East of central NSLF in RAB
Shallow
632.88
20.00
35.00
20.98
611.90
22.12
610.76
23.45
609.43
23.45
609.43
AB-34D
East of central NSLF in RAB
Deep
632.93
138.00
143.00
22.86
610.07
23.25
609.68
23.31
609.62
22.52
610.41
AB-35D
East of NSLF in DORS
Deep
664.55
116.00
121.00
47.42
617.13
47.46
617.09
47.45
617.10
47.49
617.06
AB-35S
East of NSLF in DORS
Ash Pore Water
664.47
35.00
50.00
BTP
BTP
46.80
617.67
46.86
617.61
46.83
617.64
AB-35PWS
East of NSLF in DORS
Shallow
663.47
89.00
99.00
46.79
616.68
46.72
616.75
46.80
616.67
46.85
616.62
AB-39D
East of NSLF in DORS
Deep
637.46
83.00
88.00
20.96
616.50
21.10
616.36
21.10
616.36
21.26
616.20
AB-39S
East of NSLF in DORS
Ash Pore Water
637.47
30.00
45.00
21.24
616.23
21.46
616.01
21.45
616.02
21.70
615.77
CCR-BG-IDA
West of NSLF outside RAB
Deep
661.17
122.38
127.38
33.13
628.04
33.29
627.88
33.20
627.97
33.23
627.94
CCR-BG-1S
West of NSLF outside RAB
Shallow
660.37
39.98
54.98
33.94
626.43
34.00
626.37
33.85
626.52
33.68
626.69
GWA-15D
Southwest of NSLF outside RAB
Deep
633.27
84.50
89.50
9.57
623.70
9.42
623.85
9.55
623.72
9.40
623.87
GWA-15S
Southwest of NSLF outside RAB
Shallow
632.71
17.00
32.00
8.70
624.01
8.68
624.03
8.76
623.95
8.69
624.02
Notes:
Summary table originally developed by SynTerra and modified by Duke Energy for this submittal.
negative variance between top of CSL elevation and most recent water level elevation; denotes water level meets vertical separation criteria
= positive variance between top of CSL elevation and most recent water level elevation; denotes water level still needs to decrease by respective value to meet vertical separation criteria
*Top of PVC well casing for NSLF-PZ-04 was cut down to 616.54 in mid -April 2022
^ - target elevation for a minimum of 5 feet of vertical separation from future top of CSL based on revised NSLF sump location (see AECOM PTC Modification Request dated 12/14/2022)
NSLF-PZ-01 through NSLF-PZ-04 installed October 2021. NSLF-PZ-05 installed August 2022. Other well locations shown were previously installed under CAMA and/or CCR programs.
BTP - well is fitted with a dedicated bladder pump and water level occurs below top of the pump, preventing a water level measurement without disturbing the water column.
BGS - below ground surface
BTOC - below top of casing
CSL - compacted soil liner
DORS - distribution of residual solids
Dry - well was dry at time of water level sweep.
Ft - feet
N/A - not applicable
NA - not available
NAVD 88 - North American Vertical Datum of 1988.
NM - not measured
RAB - retired ash basin
Page 3 of 14

TABLE 1 - GROUNDWATER ELEVATIONS
ALLEN STEAM STATION - NSLF
Well ID
Location Description Relative to NSLF
Monitoring
Flow
Zone
Top of Well
Casing
(ft-NAVD 88)*
Screened
Interval
(Ft-BGS)
02/02/2022
02/10/2022
02/18/2022
Depth to Water
(Ft-BTOC)
Groundwater
Elevation
(Ft-NAVD 88)
Depth to Water
(Ft-BTOC)
Groundwater
Elevation
(Ft-NAVD 88)
Depth to Water
(Ft-BTOC)
Groundwater
Elevation
(Ft-NAVD 88)
NSLF-PZ-01
Within NSLF Footprint - North End
Shallow
631.11
3.00
13.00
10.40
620.71
10.05
621.06
10.80
620.31
NSLF-PZ-02
Within NSLF Footprint - Central
Shallow
626.76
3.00
13.00
7.69
619.07
6.60
620.16
7.50
619.26
NSLF-PZ-03
East of central NSLF in RAB
Shallow
640.47
13.00
38.00
23.25
617.22
23.33
617.14
23.45
617.02
NSLF-PZ-04
Within NSLF footprint -135' Northeast of sump
Shallow
624.57
10.00
20.00
10.04
614.53
10.10
614.47
10.50
614.07
NSLF-PZ-05
Within Revised NSLF Sump Area
Shallow
614.13
5.00
20.00
N/A
N/A
N/A
N/A
N/A
N/A
AB-1R
Northwest of NSLF outside RAB
Shallow
675.86
51.00
71.00
51.08
624.78
51.05
624.81
51.14
624.72
AB-2
South of NSLF just outside RAB
Shallow
638.74
4.00
19.00
22.08
616.66
22.08
616.66
22.10
616.64
AB-2D
South of NSLF just outside RAB
Deep
638.33
65.00
70.00
25.78
612.55
25.82
612.51
25.91
612.42
AB-34S
East of central NSLF in RAB
Shallow
632.88
20.00
35.00
23.47
609.41
22.54
610.34
22.62
610.26
AB-34D
East of central NSLF in RAB
Deep
632.93
138.00
143.00
22.50
610.43
23.51
609.42
23.51
609.42
AB-35D
East of NSLF in DORS
Deep
664.55
116.00
121.00
47.55
617.00
47.54
617.01
47.55
617.00
AB-35S
East of NSLF in DORS
Ash Pore Water
664.47
35.00
50.00
1 46.82
617.65
46.82
617.65
BTP
BTP
AB-35PWS
East of NSLF in DORS
Shallow
663.47
89.00
99.00
46.90
616.57
46.90
616.57
46.90
616.57
AB-39D
East of NSLF in DORS
Deep
637.46
83.00
88.00
21.32
616.14
21.38
616.08
21.52
615.94
AB-39S
East of NSLF in DORS
Ash Pore Water
637.47
30.00
45.00
21.73
615.74
21.83
615.64
22.00
615.47
CCR-BG-IDA
West of NSLF outside RAB
Deep
661.17
122.38
127.38
33.21
627.96
33.20
627.97
33.23
627.94
CCR-BG-1S
West of NSLF outside RAB
Shallow
660.37
39.98
54.98
33.65
626.72
33.56
626.81
33.72
626.65
GWA-15D
Southwest of NSLF outside RAB
Deep
633.27
84.50
89.50
9.54
623.73
9.33
623.94
9.40
623.87
GWA-15S
Southwest of NSLF outside RAB
Shallow
632.71
17.00
32.00
8.80
623.91
8.62
624.09
8.62
624.09
Notes:
Summary table originally developed by SynTerra and modified by Duke Energy for this submittal.
negative variance between top of CSL elevation and most recent water level elevation; denotes water level meets vertical separation criteria
= positive variance between top of CSL elevation and most recent water level elevation; denotes water level still needs to decrease by respective value to meet vertical separation criteria
*Top of PVC well casing for NSLF-PZ-04 was cut down to 616.54 in mid -April 2022
^ - target elevation for a minimum of 5 feet of vertical separation from future top of CSL based on revised NSLF sump location (see AECOM PTC Modification Request dated 12/14/2022)
NSLF-PZ-01 through NSLF-PZ-04 installed October 2021. NSLF-PZ-05 installed August 2022. Other well locations shown were previously installed under CAMA and/or CCR programs.
BTP - well is fitted with a dedicated bladder pump and water level occurs below top of the pump, preventing a water level measurement without disturbing the water column.
BGS - below ground surface
BTOC - below top of casing
CSL - compacted soil liner
DORS - distribution of residual solids
Dry - well was dry at time of water level sweep.
Ft - feet
N/A - not applicable
NA - not available
NAVD 88 - North American Vertical Datum of 1988.
NM - not measured
RAB - retired ash basin
Page 4 of 14

TABLE 1 - GROUNDWATER ELEVATIONS
ALLEN STEAM STATION - NSLF
Well ID
Location Description Relative to NSLF
Monitoring
Flow
Zone
Top of Well
Casing
(ft-NAVD 88)*
Screened
Interval
(Ft-BGS)
02/25/2022
03/04/2022
03/11/2022
03/18/2022
Depth to Water
(Ft-BTOC)
Groundwater
Elevation
(Ft-NAVD 88)
Depth to Water
(Ft-BTOC)
Groundwater
Elevation
(Ft-NAVD 88)
Depth to Water
(Ft-BTOC)
Groundwater
Elevation
(Ft-NAVD 88)
Depth to Water
(Ft-BTOC)
Groundwater
Elevation
(Ft-NAVD 88)
NSLF-PZ-01
Within NSLF Footprint - North End
Shallow
631.11
3.00
13.00
10.90
620.21
11.15
619.96
10.92
620.19
10.70
620.41
NSLF-PZ-02
Within NSLF Footprint - Central
Shallow
626.76
3.00
13.00
7.48
619.28
8.54
618.22
7.09
619.67
6.56
620.20
NSLF-PZ-03
East of central NSLF in RAB
Shallow
640.47
13.00
38.00
23.55
616.92
23.62
616.85
23.55
616.92
23.22
617.25
NSLF-PZ-04
Within NSLF footprint -135' Northeast of sump
Shallow
624.57
10.00
20.00
10.68
613.89
11.13
613.44
10.40
614.17
10.30
614.27
NSLF-PZ-05
Within Revised NSLF Sump Area
Shallow
614.13
5.00
20.00
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
AB-1R
Northwest of NSLF outside RAB
Shallow
675.86
51.00
71.00
51.35
624.51
51.72
624.14
51.44
624.42
51.58
624.28
AB-2
South of NSLF just outside RAB
Shallow
638.74
4.00
19.00
22.11
616.63
22.14
616.60
21.45
617.29
20.55
618.19
AB-2D
South of NSLF just outside RAB
Deep
638.33
65.00
70.00
26.08
612.25
26.39
611.94
24.75
613.58
24.10
614.23
AB-34S
East of central NSLF in RAB
Shallow
632.88
20.00
35.00
NM
NM
22.84
610.04
22.75
610.13
NM
NM
AB-34D
East of central NSLF in RAB
Deep
632.93
138.00
143.00
NM
NM
23.77
609.16
23.70
609.23
NM
NM
AB-35D
East of NSLF in DORS
Deep
664.55
116.00
121.00
47.65
616.90
47.80
616.75
47.48
617.07
47.15
617.40
AB-35S
East of NSLF in DORS
Ash Pore Water
664.47
35.00
50.00
BTP
BTP
BTP
BTP
46.80
617.67
46.69
617.78
AB-35PWS
East of NSLF in DORS
Shallow
663.47
89.00
99.00
47.00
616.47
47.20
616.27
46.85
616.62
46.57
616.90
AB-39D
East of NSLF in DORS
Deep
637.46
83.00
88.00
21.59
615.87
21.74
615.72
21.67
615.79
21.46
616.00
AB-39S
East of NSLF in DORS
Ash Pore Water
637.47
30.00
45.00
22.05
615.42
22.20
615.27
22.10
615.37
22.11
615.36
CCR-BG-IDA
West of NSLF outside RAB
Deep
661.17
122.38
127.38
33.33
627.84
33.50
627.67
33.29
627.88
33.13
628.04
CCR-BG-1S
West of NSLF outside RAB
Shallow
660.37
39.98
54.98
33.89
626.48
33.95
626.42
33.90
626.47
33.65
626.72
GWA-15D
Southwest of NSLF outside RAB
Deep
633.27
84.50
89.50
9.30
623.97
9.45
623.82
9.00
624.27
9.00
624.27
GWA-15S
Southwest of NSLF outside RAB
Shallow
632.71
17.00
1 32.00
8.63
624.08
8.70
624.01
8.22
624.49
8.20
624.51
Notes:
Summary table originally developed by SynTerra and modified by Duke Energy for this submittal.
negative variance between top of CSL elevation and most recent water level elevation; denotes water level meets vertical separation criteria
= positive variance between top of CSL elevation and most recent water level elevation; denotes water level still needs to decrease by respective value to meet vertical separation criteria
*Top of PVC well casing for NSLF-PZ-04 was cut down to 616.54 in mid -April 2022
^ - target elevation for a minimum of 5 feet of vertical separation from future top of CSL based on revised NSLF sump location (see AECOM PTC Modification Request dated 12/14/2022)
NSLF-PZ-01 through NSLF-PZ-04 installed October 2021. NSLF-PZ-05 installed August 2022. Other well locations shown were previously installed under CAMA and/or CCR programs.
BTP - well is fitted with a dedicated bladder pump and water level occurs below top of the pump, preventing a water level measurement without disturbing the water column.
BGS - below ground surface
BTOC - below top of casing
CSL - compacted soil liner
DORS - distribution of residual solids
Dry - well was dry at time of water level sweep.
Ft - feet
N/A - not applicable
NA - not available
NAVD 88 - North American Vertical Datum of 1988.
NM - not measured
RAB - retired ash basin
Page 5 of 14

TABLE 1 - GROUNDWATER ELEVATIONS
ALLEN STEAM STATION - NSLF
Well ID
Location Description Relative to NSLF
Monitoring
Flow
Zone
Top of Well
Casing
(ft-NAVD 88)*
Screened
Interval
(Ft-BGS)
04/01/2022
04/15/2022
04/29/2022
06/03/2022
Depth to Water
(Ft-BTOC)
Groundwater
Elevation
(Ft-NAVD 88)
Depth to Water
(Ft-BTOC)
Groundwater
Elevation
(Ft-NAVD 88)
Depth to Water
(Ft-BTOC)
Groundwater
Elevation
(Ft-NAVD 88)
Depth to Water
(Ft-BTOC)
Groundwater
Elevation
(Ft-NAVD 88)
NSLF-PZ-01
Within NSLF Footprint - North End
Shallow
631.11
3.00
13.00
11.65
619.46
12.22
618.89
12.90
618.21
13.89
617.22
NSLF-PZ-02
Within NSLF Footprint - Central
Shallow
626.76
3.00
13.00
8.65
618.11
10.23
616.53
10.62
616.14
12.15
614.61
NSLF-PZ-03
East of central NSLF in RAB
Shallow
640.47
13.00
38.00
23.62
616.85
23.78
616.69
24.08
616.39
25.50
614.97
NSLF-PZ-04
Within NSLF footprint -135' Northeast of sump
Shallow
624.57
10.00
20.00
11.30
613.27
4.05
612.49
4.40
612.14
7.40
609.14
NSLF-PZ-05
Within Revised NSLF Sump Area
Shallow
614.13
5.00
20.00
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
AB-1R
Northwest of NSLF outside RAB
Shallow
675.86
51.00
71.00
1 51.84
624.02
52.03
623.83
52.81
623.05
52.46
623.40
AB-2
South of NSLF just outside RAB
Shallow
638.74
4.00
19.00
21.30
617.44
21.05
617.69
21.50
617.24
22.15
616.59
AB-2D
South of NSLF just outside RAB
Deep
638.33
65.00
70.00
24.58
613.75
24.66
613.67
24.83
613.50
26.50
611.83
AB-34S
East of central NSLF in RAB
Shallow
632.88
20.00
35.00
NM
NM
22.54
610.34
22.33
610.55
22.83
610.05
AB-34D
East of central NSLF in RAB
Deep
632.93
138.00
143.00
NM
NM
23.57
609.36
23.54
609.39
23.85
609.08
AB-35D
East of NSLF in DORS
Deep
664.55
116.00
121.00
47.12
617.43
47.08
617.47
47.12
617.43
48.42
616.13
AB-35S
East of NSLF in DORS
Ash Pore Water
664.47
35.00
50.00
46.58
617.89
46.35
618.12
46.33
618.14
BTP
BTP
AB-35PWS
East of NSLF in DORS
Shallow
663.47
89.00
99.00
46.50
616.97
46.45
617.02
46.45
617.02
47.69
615.78
AB-39D
East of NSLF in DORS
Deep
637.46
83.00
88.00
21.55
615.91
21.60
615.86
21.76
615.70
22.43
615.03
AB-39S
East of NSLF in DORS
Ash Pore Water
637.47
30.00
45.00
22.16
615.31
22.16
615.31
22.24
615.23
22.64
614.83
CCR-BG-IDA
West of NSLF outside RAB
Deep
661.17
122.38
127.38
33.15
628.02
33.23
627.94
33.26
627.91
33.80
627.37
CCR-BG-1S
West of NSLF outside RAB
Shallow
660.37
39.98
54.98
33.65
626.72
33.87
626.50
34.00
626.37
34.90
625.47
GWA-15D
Southwest of NSLF outside RAB
Deep
633.27
84.50
89.50
9.10
624.17
9.24
624.03
9.30
623.97
9.74
623.53
GWA-15S
Southwest of NSLF outside RAB
Shallow
632.71
17.00
32.00
8.20
624.51
8.45
624.26
8.48
624.23
8.98
623.73
Notes:
Summary table originally developed by SynTerra and modified by Duke Energy for this submittal.
negative variance between top of CSL elevation and most recent water level elevation; denotes water level meets vertical separation criteria
= positive variance between top of CSL elevation and most recent water level elevation; denotes water level still needs to decrease by respective value to meet vertical separation criteria
*Top of PVC well casing for NSLF-PZ-04 was cut down to 616.54 in mid -April 2022
^ - target elevation for a minimum of 5 feet of vertical separation from future top of CSL based on revised NSLF sump location (see AECOM PTC Modification Request dated 12/14/2022)
NSLF-PZ-01 through NSLF-PZ-04 installed October 2021. NSLF-PZ-05 installed August 2022. Other well locations shown were previously installed under CAMA and/or CCR programs.
BTP - well is fitted with a dedicated bladder pump and water level occurs below top of the pump, preventing a water level measurement without disturbing the water column.
BGS - below ground surface
BTOC - below top of casing
CSL - compacted soil liner
DORS - distribution of residual solids
Dry - well was dry at time of water level sweep.
Ft - feet
N/A - not applicable
NA - not available
NAVD 88 - North American Vertical Datum of 1988.
NM - not measured
RAB - retired ash basin
Page 6 of 14

TABLE 1 - GROUNDWATER ELEVATIONS
ALLEN STEAM STATION - NSLF
Well ID
Location Description Relative to NSLF
Monitoring
Flow
Zone
Top of Well
Casing
(ft-NAVD 88)*
Screened
Interval
(Ft-BGS)
06/13/2022
06/20/2022
06/24/2022
07/01/2022
Depth to Water
(Ft-BTOC)
Groundwater
Elevation
(Ft-NAVD 88)
Depth to Water
(Ft-BTOC)
Groundwater
Elevation
(Ft-NAVD 88)
Depth to Water
(Ft-BTOC)
Groundwater
Elevation
(Ft-NAVD 88)
Depth to Water
(Ft-BTOC)
Groundwater
Elevation
(Ft-NAVD 88)
NSLF-PZ-01
Within NSLF Footprint - North End
Shallow
631.11
3.00
13.00
14.04
617.07
13.98
617.13
14.12
616.99
14.15
616.96
NSLF-PZ-02
Within NSLF Footprint - Central
Shallow
626.76
3.00
13.00
12.74
614.02
12.96
613.80
13.05
613.71
12.70
614.06
NSLF-PZ-03
East of central NSLF in RAB
Shallow
640.47
13.00
38.00
25.94
614.53
26.15
614.32
26.24
614.23
24.67
615.80
NSLF-PZ-04
Within NSLF footprint -135' Northeast of sump
Shallow
624.57
10.00
20.00
7.54
609.00
7.75
608.79
7.80
608.74
7.66
608.88
NSLF-PZ-05
Within Revised NSLF Sump Area
Shallow
614.13
5.00
20.00
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
AB-1R
Northwest of NSLF outside RAB
Shallow
675.86
51.00
71.00
52.78
623.08
52.84
623.02
52.82
623.04
52.88
622.98
A13-2
South of NSLF just outside RAB
Shallow
638.74
4.00
19.00
BTP
BTP
22.15
616.59
Dry
Dry
Dry
Dry
A13-2D
South of NSLF just outside RAB
Deep
638.33
65.00
70.00
27.08
611.25
27.61
610.72
27.78
610.55
27.85
610.48
AB-34S
East of central NSLF in RAB
Shallow
632.88
20.00
35.00
1 23.05
609.83
22.92
609.96
22.90
609.98
23.25
609.63
AB-34D
East of central NSLF in RAB
Deep
632.93
138.00
143.00
24.05
608.88
24.11
608.82
24.16
608.77
24.85
608.08
AB-35D
East of NSLF in DORS
Deep
664.55
116.00
121.00
48.83
615.72
49.02
615.53
49.11
615.44
49.28
615.27
AB-35S
East of NSLF in DORS
Ash Pore Water
664.47
35.00
50.00
BTP
BTP
BTP
BTP
BTP
BTP
BTP
BTP
AB-35PWS
East of NSLF in DORS
Shallow
663.47
89.00
99.00
48.07
615.40
48.33
615.14
48.36
615.11
48.55
614.92
AB-39D
East of NSLF in DORS
Deep
637.46
83.00
88.00
22.65
614.81
22.76
614.70
22.82
614.64
22.90
614.56
AB-39S
East of NSLF in DORS
Ash Pore Water
637.47
30.00
45.00
22.84
614.63
22.86
614.61
22.92
614.55
23.00
614.47
CCR-BG-IDA
West of NSLF outside RAB
Deep
661.17
122.38
127.38
34.12
627.05
34.20
626.97
34.38
626.79
34.50
626.67
CCR-BG-IS
West of NSLF outside RAB
Shallow
660.37
39.98
54.98
BTP
BTP
BTP
BTP
BTP
BTP
BTP
BTP
GWA-15D
Southwest of NSLF outside RAB
Deep
633.27
84.50
89.50
9.95
623.32
9.98
623.29
10.08
623.19
10.10
623.17
GWA-15S
Southwest of NSLF outside RAB
Shallow
632.71
17.00
32.00
9.22
623.49
9.25
623.46
9.38
623.33
9.40
623.31
Notes:
Summary table originally developed by SynTerra and modified by Duke Energy for this submittal.
negative variance between top of CSL elevation and most recent water level elevation; denotes water level meets vertical separation criteria
= positive variance between top of CSL elevation and most recent water level elevation; denotes water level still needs to decrease by respective value to meet vertical separation criteria
*Top of PVC well casing for NSLF-PZ-04 was cut down to 616.54 in mid -April 2022
^ - target elevation for a minimum of 5 feet of vertical separation from future top of CSL based on revised NSLF sump location (see AECOM PTC Modification Request dated 12/14/2022)
NSLF-PZ-01 through NSLF-PZ-04 installed October 2021. NSLF-PZ-05 installed August 2022. Other well locations shown were previously installed under CAMA and/or CCR programs.
BTP - well is fitted with a dedicated bladder pump and water level occurs below top of the pump, preventing a water level measurement without disturbing the water column.
BGS - below ground surface
BTOC - below top of casing
CSL - compacted soil liner
DORS - distribution of residual solids
Dry - well was dry at time of water level sweep.
Ft - feet
N/A - not applicable
NA - not available
NAVD 88 - North American Vertical Datum of 1988.
NM - not measured
RAB - retired ash basin
Page 7 of 14

TABLE 1 - GROUNDWATER ELEVATIONS
ALLEN STEAM STATION - NSLF
Well ID
Location Description Relative to NSLF
Monitoring
Flow
Zone
Top of Well
Casing
(ft-NAVD 88)*
Screened
Interval
(Ft-BGS)
07/08/2022
07/15/2022
07/19/2022
07/22/2022
Depth to Water
(Ft-BTOC)
Groundwater
Elevation
(Ft-NAVD 88)
Depth to Water
(Ft-BTOC)
Groundwater
Elevation
(Ft-NAVD 88)
Depth to Water
(Ft-BTOC)
Groundwater
Elevation
(Ft-NAVD 88)
Depth to Water
(Ft-BTOC)
Groundwater
Elevation
(Ft-NAVD 88)
NSLF-PZ-01
Within NSLF Footprint - North End
Shallow
631.11
3.00
13.00
14.26
616.85
14.37
616.74
14.38
616.73
14.44
616.67
NSLF-PZ-02
Within NSLF Footprint - Central
Shallow
626.76
3.00
13.00
12.18
614.58
12.01
614.75
12.34
614.42
12.36
614.40
NSLF-PZ-03
East of central NSLF in RAB
Shallow
640.47
13.00
38.00
26.65
613.82
26.82
613.65
26.94
613.53
27.08
613.39
NSLF-PZ-04
Within NSLF footprint -135' Northeast of sump
Shallow
624.57
10.00
20.00
7.89
608.65
7.88
608.66
7.95
608.59
7.99
608.55
NSLF-PZ-05
Within Revised NSLF Sump Area
Shallow
614.13
5.00
20.00
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
AB-1R
Northwest of NSLF outside RAB
Shallow
675.86
51.00
71.00
53.05
622.81
53.22
622.64
NM
NM
53.27
622.59
A13-2
South of NSLF just outside RAB
Shallow
638.74
4.00
19.00
Dry
Dry
Dry
Dry
NM
NM
Dry
Dry
AB-2D
South of NSLF just outside RAB
Deep
638.33
65.00
70.00
28.30
610.03
28.23
610.10
NM
NM
28.42
609.91
AB-34S
East of central NSLF in RAB
Shallow
632.88
20.00
35.00
1 23.41
609.47
22.94
609.94
NM
NM
23.53
609.35
AB-34D
East of central NSLF in RAB
Deep
632.93
138.00
143.00
25.09
607.84
23.98
608.95
NM
NM
24.60
608.33
AB-35D
East of NSLF in DORS
Deep
664.55
116.00
121.00
49.42
615.13
49.59
614.96
NM
NM
49.83
614.72
AB-35S
East of NSLF in DORS
Ash Pore Water
664.47
35.00
50.00
BTP
BTP
BTP
BTP
NM
NM
BTP
BTP
AB-35PWS
East of NSLF in DORS
Shallow
663.47
89.00
99.00
48.80
614.67
48.85
614.62
NM
NM
49.08
614.39
AB-39D
East of NSLF in DORS
Deep
637.46
83.00
88.00
23.04
614.42
23.20
614.26
NM
NM
23.42
614.04
AB-39S
East of NSLF in DORS
Ash Pore Water
637.47
30.00
45.00
23.15
614.32
23.24
614.23
NM
NM
23.43
614.04
CCR-BG-IDA
West of NSLF outside RAB
Deep
661.17
122.38
127.38
34.73
626.44
34.82
626.35
NM
NM
34.88
626.29
CCR-BG-IS
West of NSLF outside RAB
Shallow
660.37
39.98
54.98
BTP
BTP
BTP
BTP
NM
NM
BTP
BTP
GWA-15D
Southwest of NSLF outside RAB
Deep
633.27
84.50
89.50
10.22
623.05
10.30
622.97
NM
NM
10.40
622.87
GWA-15S
Southwest of NSLF outside RAB
Shallow
632.71
17.00
32.00
9.56
623.15
9.64
623.07
NM
NM
9.76
622.95
Notes:
Summary table originally developed by SynTerra and modified by Duke Energy for this submittal.
negative variance between top of CSL elevation and most recent water level elevation; denotes water level meets vertical separation criteria
= positive variance between top of CSL elevation and most recent water level elevation; denotes water level still needs to decrease by respective value to meet vertical separation criteria
*Top of PVC well casing for NSLF-PZ-04 was cut down to 616.54 in mid -April 2022
^ - target elevation for a minimum of 5 feet of vertical separation from future top of CSL based on revised NSLF sump location (see AECOM PTC Modification Request dated 12/14/2022)
NSLF-PZ-01 through NSLF-PZ-04 installed October 2021. NSLF-PZ-05 installed August 2022. Other well locations shown were previously installed under CAMA and/or CCR programs.
BTP - well is fitted with a dedicated bladder pump and water level occurs below top of the pump, preventing a water level measurement without disturbing the water column.
BGS - below ground surface
BTOC - below top of casing
CSL - compacted soil liner
DORS - distribution of residual solids
Dry - well was dry at time of water level sweep.
Ft - feet
N/A - not applicable
NA - not available
NAVD 88 - North American Vertical Datum of 1988.
NM - not measured
RAB - retired ash basin
Page 8 of 14

TABLE 1 - GROUNDWATER ELEVATIONS
ALLEN STEAM STATION - NSLF
Well ID
Location Description Relative to NSLF
Monitoring
Flow
Zone
Top of Well
Casing
(ft-NAVD 88)*
Screened
Interval
(Ft-BGS)
07/26/2022
07/29/2022
08/02/2022
08/05/2022
Depth to Water
(Ft-BTOC)
Groundwater
Elevation
(Ft-NAVD 88)
Depth to Water
(Ft-BTOC)
Groundwater
Elevation
(Ft-NAVD 88)
Depth to Water
(Ft-BTOC)
Groundwater
Elevation
(Ft-NAVD 88)
Depth to Water
(Ft-BTOC)
Groundwater
Elevation
(Ft-NAVD 88)
NSLF-PZ-01
Within NSLF Footprint - North End
Shallow
631.11
3.00
13.00
14.51
616.60
14.65
616.46
14.50
616.61
14.63
616.48
NSLF-PZ-02
Within NSLF Footprint - Central
Shallow
626.76
3.00
13.00
12.65
614.11
12.76
614.00
12.43
614.33
No Access
---
NSLF-PZ-03
East of central NSLF in RAB
Shallow
640.47
13.00
38.00
27.08
613.39
27.19
613.28
27.25
613.22
27.33
613.14
NSLF-PZ-04
Within NSLF footprint -135' Northeast of sump
Shallow
624.57
10.00
20.00
8.09
608.45
8.20
608.34
8.11
608.43
8.21
608.33
NSLF-PZ-05
Within Revised NSLF Sump Area
Shallow
614.13
5.00
20.00
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
AB-1R
Northwest of NSLF outside RAB
Shallow
675.86
51.00
71.00
53.35
622.51
53.45
622.41
53.45
622.41
53.54
622.32
A13-2
South of NSLF just outside RAB
Shallow
638.74
4.00
19.00
Dry
Dry
Dry
Dry
Dry
Dry
Dry
Dry
A13-21D
South of NSLF just outside RAB
Deep
638.33
65.00
70.00
28.52
609.81
28.80
609.53
28.74
609.59
28.76
609.57
AB-34S
East of central NSLF in RAB
Shallow
632.88
20.00
35.00
23.51
609.37
23.52
609.36
23.68
609.20
23.70
609.18
AB-34D
East of central NSLF in RAB
Deep
632.93
138.00
143.00
24.60
608.33
24.61
608.32
24.74
608.19
24.75
608.18
AB-35D
East of NSLF in DORS
Deep
664.55
116.00
121.00
49.90
614.65
49.98
614.57
49.96
614.59
49.97
614.58
AB-35S
East of NSLF in DORS
Ash Pore Water
664.47
35.00
50.00
BTP
BTP
BTP
BTP
BTP
BTP
BTP
BTP
AB-35PWS
East of NSLF in DORS
Shallow
663.47
89.00
99.00
49.18
614.29
49.25
614.22
49.26
614.21
49.28
614.19
AB-39D
East of NSLF in DORS
Deep
637.46
83.00
88.00
23.41
614.05
23.53
613.93
23.52
613.94
23.55
613.91
AB-39S
East of NSLF in DORS
Ash Pore Water
637.47
30.00
45.00
23.40
614.07
23.53
613.94
23.54
613.93
23.54
613.93
CCR-BG-IDA
West of NSLF outside RAB
Deep
661.17
122.38
127.38
35.08
626.09
35.23
625.94
35.20
625.97
35.31
625.86
CCR-BG-IS
West of NSLF outside RAB
Shallow
660.37
39.98
54.98
BTP
BTP
BTP
BTP
BTP
BTP
BTP
BTP
GWA-15D
Southwest of NSLF outside RAB
Deep
633.27
84.50
89.50
10.42
622.85
10.43
622.84
10.36
622.91
10.33
622.94
GWA-15S
Southwest of NSLF outside RAB
Shallow
632.71
17.00
32.00
9.80
622.91
9.56
623.15
9.74
622.97
9.59
623.12
Notes:
Summary table originally developed by SynTerra and modified by Duke Energy for this submittal.
negative variance between top of CSL elevation and most recent water level elevation; denotes water level meets vertical separation criteria
= positive variance between top of CSL elevation and most recent water level elevation; denotes water level still needs to decrease by respective value to meet vertical separation criteria
*Top of PVC well casing for NSLF-PZ-04 was cut down to 616.54 in mid -April 2022
^ - target elevation for a minimum of 5 feet of vertical separation from future top of CSL based on revised NSLF sump location (see AECOM PTC Modification Request dated 12/14/2022)
NSLF-PZ-01 through NSLF-PZ-04 installed October 2021. NSLF-PZ-05 installed August 2022. Other well locations shown were previously installed under CAMA and/or CCR programs.
BTP - well is fitted with a dedicated bladder pump and water level occurs below top of the pump, preventing a water level measurement without disturbing the water column.
BGS - below ground surface
BTOC - below top of casing
CSL - compacted soil liner
DORS - distribution of residual solids
Dry - well was dry at time of water level sweep.
Ft - feet
N/A - not applicable
NA - not available
NAVD 88 - North American Vertical Datum of 1988.
NM - not measured
RAB - retired ash basin
Page 9 of 14

TABLE 1 - GROUNDWATER ELEVATIONS
ALLEN STEAM STATION - NSLF
Well ID
Location Description Relative to NSLF
Monitoring
Flow
Zone
Top of Well
Casing
(ft-NAVD 88)*
Screened
Interval
(Ft-BGS)
08/09/2022
08/17/2022
09/01/2022
09/08/2022
Depth to Water
(Ft-BTOC)
Groundwater
Elevation
(Ft-NAVD 88)
Depth to Water
(Ft-BTOC)
Groundwater
Elevation
(Ft-NAVD 88)
Depth to Water
(Ft-BTOC)
Groundwater
Elevation
(Ft-NAVD 88)
Depth to Water
(Ft-BTOC)
Groundwater
Elevation
(Ft-NAVD 88)
NSLF-PZ-01
Within NSLF Footprint - North End
Shallow
631.11
3.00
13.00
14.63
616.48
14.82
616.29
15.07
616.04
15.13
615.98
NSLF-PZ-02
Within NSLF Footprint - Central
Shallow
626.76
3.00
13.00
12.48
614.28
12.98
613.78
13.09
613.67
13.10
613.66
NSLF-PZ-03
East of central NSLF in RAB
Shallow
640.47
13.00
38.00
27.38
613.09
27.54
612.93
27.86
612.61
27.99
612.48
NSLF-PZ-04
Within NSLF footprint -135' Northeast of sump
Shallow
624.57
10.00
20.00
8.10
608.44
8.49
608.05
8.75
607.79
8.97
607.57
NSLF-PZ-05
Within Revised NSLF Sump Area
Shallow
614.13
5.00
20.00
N/A
N/A
N/A
N/A
7.50
606.63
7.91
606.22
AB-1R
Northwest of NSLF outside RAB
Shallow
675.86
51.00
71.00
53.53
622.33
53.68
622.18
53.97
621.89
53.99
621.87
A13-2
South of NSLF just outside RAB
Shallow
638.74
4.00
19.00
22.20
616.54
22.20
616.54
Dry
Dry
Dry
Dry
A13-21D
South of NSLF just outside RAB
Deep
638.33
65.00
70.00
29.33
609.00
29.38
608.95
30.35
607.98
30.40
607.93
AB-34S
East of central NSLF in RAB
Shallow
632.88
20.00
35.00
1 23.40
609.48
23.46
609.42
24.25
608.63
24.20
608.68
AB-34D
East of central NSLF in RAB
Deep
632.93
138.00
143.00
24.84
608.09
24.90
608.03
25.29
607.64
23.90
609.03
AB-35D
East of NSLF in DORS
Deep
664.55
116.00
121.00
51.10
613.45
51.17
613.38
50.71
613.84
50.82
613.73
AB-35S
East of NSLF in DORS
Ash Pore Water
664.47
35.00
50.00
BTP
BTP
BTP
BTP
BTP
BTP
BTP
BTP
AB-35PWS
East of NSLF in DORS
Shallow
663.47
89.00
99.00
49.40
614.07
49.61
613.86
49.90
613.57
50.05
613.42
AB-39D
East of NSLF in DORS
Deep
637.46
83.00
88.00
23.64
613.82
23.77
613.69
24.05
613.41
24.17
613.29
AB-39S
East of NSLF in DORS
Ash Pore Water
637.47
30.00
45.00
23.62
613.85
23.76
613.71
24.00
613.47
24.10
613.37
CCR-BG-IDA
West of NSLF outside RAB
Deep
661.17
122.38
127.38
35.34
625.83
35.50
625.67
35.88
625.29
35.98
625.19
CCR-BG-IS
West of NSLF outside RAB
Shallow
660.37
39.98
54.98
BTP
BTP
BTP
BTP
BTP
BTP
BTP
BTP
GWA-15D
Southwest of NSLF outside RAB
Deep
633.27
84.50
89.50
10.48
622.79
10.53
622.74
10.70
622.57
10.75
622.52
GWA-15S
Southwest of NSLF outside RAB
Shallow
632.71
17.00
32.00
9.83
622.88
9.92
622.79
10.11
622.60
10.15
622.56
Notes:
Summary table originally developed by SynTerra and modified by Duke Energy for this submittal.
negative variance between top of CSL elevation and most recent water level elevation; denotes water level meets vertical separation criteria
= positive variance between top of CSL elevation and most recent water level elevation; denotes water level still needs to decrease by respective value to meet vertical separation criteria
*Top of PVC well casing for NSLF-PZ-04 was cut down to 616.54 in mid -April 2022
^ - target elevation for a minimum of 5 feet of vertical separation from future top of CSL based on revised NSLF sump location (see AECOM PTC Modification Request dated 12/14/2022)
NSLF-PZ-01 through NSLF-PZ-04 installed October 2021. NSLF-PZ-05 installed August 2022. Other well locations shown were previously installed under CAMA and/or CCR programs.
BTP - well is fitted with a dedicated bladder pump and water level occurs below top of the pump, preventing a water level measurement without disturbing the water column.
BGS - below ground surface
BTOC - below top of casing
CSL - compacted soil liner
DORS - distribution of residual solids
Dry - well was dry at time of water level sweep.
Ft - feet
N/A - not applicable
NA - not available
NAVD 88 - North American Vertical Datum of 1988.
NM - not measured
RAB - retired ash basin
Page 10 of 14

TABLE 1 - GROUNDWATER ELEVATIONS
ALLEN STEAM STATION - NSLF
Well ID
Location Description Relative to NSLF
Monitoring
Flow
Zone
Top of Well
Casing
(ft-NAVD 88)*
Screened
Interval
(Ft-BGS)
09/16/2022
09/20/2022
09/28/2022
10/07/2022
Depth to Water
(Ft-BTOC)
Groundwater
Elevation
(Ft-NAVD 88)
Depth to Water
(Ft-BTOC)
Groundwater
Elevation
(Ft-NAVD 88)
Depth to Water
(Ft-BTOC)
Groundwater
Elevation
(Ft-NAVD 88)
Depth to Water
(Ft-BTOC)
Groundwater
Elevation
(Ft-NAVD 88)
NSLF-PZ-01
Within NSLF Footprint - North End
Shallow
631.11
3.00
13.00
14.98
616.13
15.18
615.93
15.37
615.74
15.23
615.88
NSLF-PZ-02
Within NSLF Footprint - Central
Shallow
626.76
3.00
13.00
12.83
613.93
13.21
613.55
13.31
613.45
12.91
613.85
NSLF-PZ-03
East of central NSLF in RAB
Shallow
640.47
13.00
38.00
28.14
612.33
28.20
612.27
28.35
612.12
28.46
612.01
NSLF-PZ-04
Within NSLF footprint -135' Northeast of sump
Shallow
624.57
10.00
20.00
8.98
607.56
9.09
607.45
9.49
607.05
9.43
607.11
NSLF-PZ-05
Within Revised NSLF Sump Area
Shallow
614.13
5.00
20.00
7.91
606.22
8.04
606.09
8.95
605.18
8.70
605.43
AB-1R
Northwest of NSLF outside RAB
Shallow
675.86
51.00
71.00
54.02
621.84
54.18
621.68
54.43
621.43
54.51
621.35
A13-2
South of NSLF just outside RAB
Shallow
638.74
4.00
19.00
Dry
Dry
Dry
Dry
Dry
Dry
Dry
Dry
A13-2D
South of NSLF just outside RAB
Deep
638.33
65.00
70.00
30.46
607.87
29.90
608.43
31.23
607.10
31.13
607.20
AB-34S
East of central NSLF in RAB
Shallow
632.88
20.00
35.00
24.40
608.48
24.20
608.68
24.42
608.46
24.66
608.22
AB-34D
East of central NSLF in RAB
Deep
632.93
138.00
143.00
25.16
607.77
25.34
607.59
25.54
607.39
25.61
607.32
AB-35D
East of NSLF in DORS
Deep
664.55
116.00
121.00
50.82
613.73
50.92
613.63
51.25
613.30
51.24
613.31
AB-35S
East of NSLF in DORS
Ash Pore Water
664.47
35.00
50.00
BTP
BTP
BTP
BTP
BTP
BTP
BTP
BTP
AB-35PWS
East of NSLF in DORS
Shallow
663.47
89.00
99.00
50.04
613.43
50.11
613.36
50.45
613.02
50.42
613.05
AB-39D
East of NSLF in DORS
Deep
637.46
83.00
88.00
24.30
613.16
24.37
613.09
24.50
612.96
24.60
612.86
AB-39S
East of NSLF in DORS
Ash Pore Water
637.47
30.00
45.00
24.18
613.29
24.27
613.20
24.42
613.05
24.48
612.99
CCR-BG-IDA
West of NSLF outside RAB
Deep
661.17
122.38
127.38
36.05
625.12
36.15
625.02
36.36
624.81
36.37
624.80
CCR-BG-IS
West of NSLF outside RAB
Shallow
660.37
39.98
54.98
BTP
BTP
BTP
BTP
BTP
BTP
BTP
BTP
GWA-15D
Southwest of NSLF outside RAB
Deep
633.27
84.50
89.50
10.62
622.65
10.80
622.47
10.93
622.34
10.74
622.53
GWA-15S
Southwest of NSLF outside RAB
Shallow
632.71
17.00
32.00
10.00
622.71
10.18
622.53
10.31
622.40
10.13
622.58
Notes:
Summary table originally developed by SynTerra and modified by Duke Energy for this submittal.
negative variance between top of CSL elevation and most recent water level elevation; denotes water level meets vertical separation criteria
= positive variance between top of CSL elevation and most recent water level elevation; denotes water level still needs to decrease by respective value to meet vertical separation criteria
*Top of PVC well casing for NSLF-PZ-04 was cut down to 616.54 in mid -April 2022
^ - target elevation for a minimum of 5 feet of vertical separation from future top of CSL based on revised NSLF sump location (see AECOM PTC Modification Request dated 12/14/2022)
NSLF-PZ-01 through NSLF-PZ-04 installed October 2021. NSLF-PZ-05 installed August 2022. Other well locations shown were previously installed under CAMA and/or CCR programs.
BTP - well is fitted with a dedicated bladder pump and water level occurs below top of the pump, preventing a water level measurement without disturbing the water column.
BGS - below ground surface
BTOC - below top of casing
CSL - compacted soil liner
DORS - distribution of residual solids
Dry - well was dry at time of water level sweep.
Ft - feet
N/A - not applicable
NA - not available
NAVD 88 - North American Vertical Datum of 1988.
NM - not measured
RAB - retired ash basin
Page 11 of 14

TABLE 1 - GROUNDWATER ELEVATIONS
ALLEN STEAM STATION - NSLF
Well ID
Location Description Relative to NSLF
Monitoring
Flow
Zone
Top of Well
Casing
(ft-NAVD 88)*
Screened
Interval
(Ft-BGS)
10/14/2022
10/20/2022
10/27/2022
11/4/2022
Depth to Water
(Ft-BTOC)
Groundwater
Elevation
(Ft-NAVD 88)
Depth to Water
(Ft-BTOC)
Groundwater
Elevation
(Ft-NAVD 88)
Depth to Water
(Ft-BTOC)
Groundwater
Elevation
(Ft-NAVD 88)
Depth to Water
(Ft-BTOC)
Groundwater
Elevation
(Ft-NAVD 88)
NSLF-PZ-01
Within NSLF Footprint - North End
Shallow
631.11
3.00
13.00
15.46
615.65
15.55
615.56
15.66
615.45
15.72
615.39
NSLF-PZ-02
Within NSLF Footprint - Central
Shallow
626.76
3.00
13.00
13.08
613.68
13.25
613.51
13.40
613.36
13.43
613.33
NSLF-PZ-03
East of central NSLF in RAB
Shallow
640.47
13.00
38.00
28.57
611.90
28.70
611.77
28.78
611.69
28.92
611.55
NSLF-PZ-04
Within NSLF footprint -135' Northeast of sump
Shallow
624.57
10.00
20.00
9.49
607.05
9.65
606.89
9.78
606.76
10.14
606.40
NSLF-PZ-05
Within Revised NSLF Sump Area
Shallow
614.13
5.00
20.00
8.82
605.31
9.10
605.03
9.26
604.87
9.91
604.22
AB-1R
Northwest of NSLF outside RAB
Shallow
675.86
51.00
71.00
54.62
621.24
54.70
621.16
54.85
621.01
54.95
620.91
A13-2
South of NSLF just outside RAB
Shallow
638.74
4.00
19.00
Dry
Dry
Dry
Dry
Dry
Dry
Dry
Dry
AB-2D
South of NSLF just outside RAB
Deep
638.33
65.00
70.00
31.58
606.75
32.76
605.57
33.11
605.22
33.60
604.73
AB-34S
East of central NSLF in RAB
Shallow
632.88
20.00
35.00
24.80
608.08
24.85
608.03
24.92
607.96
25.02
607.86
AB-34D
East of central NSLF in RAB
Deep
632.93
138.00
143.00
25.72
607.21
25.80
607.13
25.88
607.05
25.97
606.96
AB-35D
East of NSLF in DORS
Deep
664.55
116.00
121.00
51.45
613.10
51.75
612.80
51.98
612.57
52.15
612.40
AB-35S
East of NSLF in DORS
Ash Pore Water
664.47
35.00
50.00
BTP
BTP
BTP
BTP
BTP
BTP
BTP
BTP
AB-35PWS
East of NSLF in DORS
Shallow
663.47
89.00
99.00
50.60
612.87
50.89
612.58
51.03
612.44
51.23
612.24
AB-39D
East of NSLF in DORS
Deep
637.46
83.00
88.00
24.67
612.79
24.74
612.72
24.87
612.59
25.00
612.46
AB-39S
East of NSLF in DORS
Ash Pore Water
637.47
30.00
45.00
24.59
612.88
24.64
612.83
24.76
612.71
24.86
612.61
CCR-BG-IDA
West of NSLF outside RAB
Deep
661.17
122.38
127.38
36.48
624.69
36.68
624.49
36.71
624.46
36.86
624.31
CCR-BG-IS
West of NSLF outside RAB
Shallow
660.37
39.98
54.98
BTP
BTP
BTP
BTP
BTP
BTP
BTP
BTP
GWA-15D
Southwest of NSLF outside RAB
Deep
633.27
84.50
89.50
10.81
622.46
10.94
622.33
10.95
622.32
11.00
622.27
GWA-15S
Southwest of NSLF outside RAB
Shallow
632.71
17.00
32.00
10.23
622.48
10.33
622.38
10.37
622.34
10.40
622.31
Notes:
Summary table originally developed by SynTerra and modified by Duke Energy for this submittal.
negative variance between top of CSL elevation and most recent water level elevation; denotes water level meets vertical separation criteria
= positive variance between top of CSL elevation and most recent water level elevation; denotes water level still needs to decrease by respective value to meet vertical separation criteria
*Top of PVC well casing for NSLF-PZ-04 was cut down to 616.54 in mid -April 2022
^ - target elevation for a minimum of 5 feet of vertical separation from future top of CSL based on revised NSLF sump location (see AECOM PTC Modification Request dated 12/14/2022)
NSLF-PZ-01 through NSLF-PZ-04 installed October 2021. NSLF-PZ-05 installed August 2022. Other well locations shown were previously installed under CAMA and/or CCR programs.
BTP - well is fitted with a dedicated bladder pump and water level occurs below top of the pump, preventing a water level measurement without disturbing the water column.
BGS - below ground surface
BTOC - below top of casing
CSL - compacted soil liner
DORS - distribution of residual solids
Dry - well was dry at time of water level sweep.
Ft - feet
N/A - not applicable
NA - not available
NAVD 88 - North American Vertical Datum of 1988.
NM - not measured
RAB - retired ash basin
Page 12 of 14

TABLE 1 - GROUNDWATER ELEVATIONS
ALLEN STEAM STATION - NSLF
Well ID
Location Description Relative to NSLF
Monitoring
Flow
Zone
Top of Well
Casing
(ft-NAVD 88)*
Screened
Interval
(Ft-BGS)
11/10/2022
12/1/2022
12/9/2022
Depth to
Water
(Ft-BTOC)
Groundwater
Elevation
(Ft-NAVD 88)
Depth to
Water
(Ft-BTOC)
Groundwater
Elevation
(Ft-NAVD 88)
Depth to
Water
(Ft-BTOC)
Groundwater
Elevation
(Ft-NAVD 88)
NSLF-PZ-01
Within NSLF Footprint - North End
Shallow
631.11
3.00
13.00
15.50
615.61
15.12
615.99
NM
NM
NSLF-PZ-02
Within NSLF Footprint - Central
Shallow
626.76
3.00
13.00
13.07
613.69
12.41
614.35
NM
NM
NSLF-PZ-03
East of central NSLF in RAB
Shallow
640.47
13.00
38.00
29.02
611.45
29.20
611.27
NM
NM
NSLF-PZ-04
Within NSLF footprint -135' Northeast of sump
Shallow
624.57
10.00
20.00
10.17
606.37
9.75
606.79
9.55
606.99
NSLF-PZ-05
Within Revised NSLF Sump Area
Shallow
614.13
5.00
20.00
No Access
No Access
9.16
604.97
9.14
604.99
AB-1R
Northwest of NSLF outside RAB
Shallow
675.86
51.00
71.00
54.86
621.00
55.36
620.50
NM
NM
AB-2
South of NSLF just outside RAB
Shallow
638.74
4.00
19.00
Dry
Dry
Dry
Dry
NM
NM
AB-2D
South of NSLF just outside RAB
Deep
638.33
65.00
70.00
33.48
604.85
32.23
606.10
NM
NM
AB-34S
East of central NSLF in RAB
Shallow
632.88
20.00
35.00
24.94
607.94
24.72
608.16
NM
NM
AB-34D
East of central NSLF in RAB
Deep
632.93
138.00
143.00
26.00
606.93
25.79
607.14
NM
NM
AB-35D
East of NSLF in DORS
Deep
664.55
116.00
121.00
52.10
612.45
52.14
612.41
NM
NM
AB-35S
East of NSLF in DORS
Ash Pore Water
664.47
35.00
50.00
BTP
BTP
BTP
BTP
NM
NM
AB-35PWS
East of NSLF in DORS
Shallow
663.47
89.00
99.00
51.17
612.30
51.21
612.26
NM
NM
AB-39D
East of NSLF in DORS
Deep
637.46
83.00
88.00
25.00
612.46
25.23
612.23
NM
NM
AB-39S
East of NSLF in DORS
Ash Pore Water
637.47
30.00
45.00
24.84
612.63
25.11
612.36
NM
NM
CCR-BG-IDA
West of NSLF outside RAB
Deep
661.17
122.38
127.38
36.82
624.35
37.69
623.48
NM
NM
CCR-BG-1S
West of NSLF outside RAB
Shallow
660.37
39.98
54.98
BTP
BTP
BTP
BTP
NM
NM
GWA-15D
Southwest of NSLF outside RAB
Deep
633.27
84.50
89.50
10.81
622.46
10.20
623.07
NM
NM
GWA-15S
Southwest of NSLF outside RAB
Shallow
632.71
17.00
32.00
10.16
622.55
9.54
623.17
NM
NM
Notes:
Summary table originally developed by SynTerra and modified by Duke Energy for this submittal.
negative variance between top of CSL elevation and most recent water level elevation; denotes water level meets vertical separation criteria
= positive variance between top of CSL elevation and most recent water level elevation; denotes water level still needs to decrease by respective value to meet vertical separation criteria
*Top of PVC well casing for NSLF-PZ-04 was cut down to 616.54 in mid -April 2022
^ - target elevation for a minimum of 5 feet of vertical separation from future top of CSL based on revised NSLF sump location (see AECOM PTC Modification Request dated 12/14/2022)
NSLF-PZ-01 through NSLF-PZ-04 installed October 2021. NSLF-PZ-05 installed August 2022. Other well locations shown were previously installed under CAMA and/or CCR programs.
BTP - well is fitted with a dedicated bladder pump and water level occurs below top of the pump, preventing a water level measurement without disturbing the water column.
BGS - below ground surface
BTOC - below top of casing
CSL - compacted soil liner
DORS - distribution of residual solids
Dry - well was dry at time of water level sweep.
Ft - feet
N/A - not applicable
NA - not available
NAVD 88 - North American Vertical Datum of 1988.
NM - not measured
RAB - retired ash basin
Page 13 of 14

TABLE 1 - GROUNDWATER ELEVATIONS
ALLEN STEAM STATION - NSLF
Well ID
Location Description Relative to NSLF
Monitoring
Flow
Zone
Top of Well
Casing
(ft-NAVD 88)*
Screened
Interval
(Ft-BGS)
Future Top
of CSL
Elevation
(Ft-NAVD
88)
Target
Elevation^
Variance
(Target
Elevation vs
Most Recent
Elevation)
Ft
NSLF-PZ-01
Within NSLF Footprint - North End
Shallow
631.11
3.00
13.00
628.20
623.20
NSLF-PZ-02
Within NSLF Footprint - Central
Shallow
626.76
3.00
13.00
623.70
618.70
NSLF-PZ-03
East of central NSLF in RAB
Shallow
640.47
13.00
38.00
N/A
N/A
N/A
NSLF-PZ-04
Within NSLF footprint -135' Northeast of sump
Shallow
624.57
10.00
20.00
613.70
608.70
NSLF-PZ-05
Within Revised NSLF Sump Area
Shallow
614.13
5.00
20.00
610.50
605.50
AB-1R
Northwest of NSLF outside RAB
Shallow
675.86
51.00
71.00
N/A
N/A
N/A
AB-2
South of NSLF just outside RAB
Shallow
638.74
4.00
19.00
N/A
N/A
N/A
AB-2D
South of NSLF just outside RAB
Deep
638.33
65.00
70.00
N/A
N/A
N/A
AB-34S
East of central NSLF in RAB
Shallow
632.88
20.00
35.00
N/A
N/A
N/A
AB-34D
East of central NSLF in RAB
Deep
632.93
138.00
143.00
N/A
N/A
N/A
AB-35D
East of NSLF in DORS
Deep
664.55
116.00
121.00
N/A
N/A
N/A
AB-35S
East of NSLF in DORS
Ash Pore Water
664.47
35.00
50.00
N/A
N/A
N/A
AB-35PWS
East of NSLF in DORS
Shallow
663.47
89.00
99.00
N/A
N/A
N/A
AB-39D
East of NSLF in DORS
Deep
637.46
83.00
88.00
N/A
N/A
N/A
AB-39S
East of NSLF in DORS
Ash Pore Water
637.47
30.00
45.00
N/A
N/A
N/A
CCR-BG-IDA
West of NSLF outside RAB
Deep
661.17
122.38
127.38
N/A
N/A
N/A
CCR-BG-IS
West of NSLF outside RAB
Shallow
660.37
39.98
54.98
N/A
N/A
N/A
GWA-15D
Southwest of NSLF outside RAB
Deep
633.27
84.50
89.50
N/A
N/A
N/A
GWA-15S
Southwest of NSLF outside RAB
Shallow
632.71
17.00
32.00
N/A
N/A
N/A
Notes:
Summary table originally developed by SynTerra and modified by Duke Energy for this submittal.
negative variance between top of CSL elevation and most recent water level elevation; denotes water level meets vertical separation criteria
= positive variance between top of CSL elevation and most recent water level elevation; denotes water level still needs to decrease by respective value to meet vertical separation criteria
*Top of PVC well casing for NSLF-PZ-04 was cut down to 616.54 in mid -April 2022
^ - target elevation for a minimum of 5 feet of vertical separation from future top of CSL based on revised NSLF sump location (see AECOM PTC Modification Request dated 12/14/2022)
NSLF-PZ-01 through NSLF-PZ-04 installed October 2021. NSLF-PZ-05 installed August 2022. Other well locations shown were previously installed under CAMA and/or CCR programs.
BTP - well is fitted with a dedicated bladder pump and water level occurs below top of the pump, preventing a water level measurement without disturbing the water column.
BGS - below ground surface
BTOC - below top of casing
CSL - compacted soil liner
DORS - distribution of residual solids
Dry - well was dry at time of water level sweep.
Ft - feet
N/A - not applicable
NA - not available
NAVD 88 - North American Vertical Datum of 1988.
NM - not measured
RAB - retired ash basin
Page 14 of 14

FIGURE 1: ALLEN STEAM STATION - NSLF
SELECT WELL/PIEZOMETER HYDROGRAPHS
NSLF-PZ-01
626
2.5
624
2
622
1.5
2
0
NSLF-PZ-01
620
m
d
—
Model Prediction
1
a
Target Elevation(623.2)
61R
—Rainfall (in)
0.5
616
614
dtlk
il
0
10/29/2021
12/18/2021
2/6/2022
3/28/2022
5/17/2022
7/6/2022 8/25/2022
10/14/2022
12/3/2022
Date
NSLF-PZ-02
626
2.5
624
—
—
2
622
620
—
1.5
C
C
_
NSLF-PZ-02
m 618 —
_
.a
f Model Prediction
W
616
1
a
♦Target Elevation (618-7)
—Rainfall (in)
614
O.5
612
A1610
L
11 dL
1"
1
0
10/29/2021
12/18/2021
216/Z022
3/28/2022
5/17/2022
7/6/2022 8/25/2022
10/14/ZOZZ
12/3/2022
Date
NSLF-PZ-03
(outside
NSLF footprint)
622
I
2.5
620
2
619
1.5
616
O
p
.� Model Prediction
LL' 614
—
1
.0 t NSLF-PZ-03
d — Rainfall (in)
612
I
0.5
610
608
(]
12/18/2C21
2/6/2022
3/28/2C22
5/17/2022
7/6/2C22 8/25/2022
10/14/2022
12/3/2022
10/29/2021
Date
NSLF-PZ-04
620
23
618
616
2
614
— —
1-5
i
0 612
c
a t NSLF-PZ-04
610
—
n f Model Prediction
1
a Target Elevation(608.7)
608
—
—Rainfall (in)
606
0.5
604
1ILLLAL
602
O
10/29/2021
12/18/2021
2/6/2022
3/28/2022
5/17/2022
7/6/2022 8/25/2022
10/14/2022
12/3/2022
Date
NSLF-PZ-05
610
2,5
NSLF-PZ-05
bog
2
installed after
modeling
606
C
1.5
w 604
1
t N5 LF- PZ-05
—Target Elevation (605.5)
602
0.5
—Rainfall (in)
600
L
A0
10/29/2021
12/18/2021
2/6/2022
3/28/2022
S/17/2022
7/6/2022 8/2S/2022
10/14/2022
12/3/2022
D ate
Hydrographs generated by SynTerra, then modified by Duke Energy. Target elevations are 4-ft below CSL subgrade (5-ft below top of CSL), and based on NSLF revised
sump location (AECOM PTC Modification Request dated 12/14/2022). Page 1 of 2

FIGURE 1: ALLEN STEAM STATION - NSLF
SELECT WELL/PIEZOMETER HYDROGRAPHS
AB-1R
630 2.5
628
2
626
15
o _
624 t Model Prediction
1 - CAB-1R
a 622 —Rainfall (in)
O.5
620
618 R1,110
3/1/2021 6/9/2021 9/17/2021 12/26/2021 4/5/2022 7/14/2022 10/22/2022
Date
AB-2D
630 2.5
625
2
620
1.5 F
C �
O p
a
615 --*---Model Prediction
n
w 1 - tAB-2D
610 ��� a —Rainfall (in)
605
0.5
—
600 0
3/1/2021 6/9/2021 9/17/2021 12/26/2021 4/5/2022 7/14/2022 10/22/2022
Date
GWA-15S
632 2.5
630 — —
2
628
Lb _
0 0
y 626 - i Model Prediction
w I n
1 .a tGWA-155
d
624 —Rainfall {in}
0.5
622
620 Ld W 0
3/1/2021 6/9/2021 9/17/2021 12/26/2021 4/5/2022 7/14/2022 10/22/2022
Date
AB-35PWS
625 2.5
620 2
615 1.5
o_ p
—*--Model Prediction
v 'a
w 610 1 �' +A6-35PWS
— Rainfall (in)
I
605 0.5
600 0
3/1/2021 6/9/2021 9/17/2021 12/26/2021 4/5/2022 7/14/2022 10/22/2022
Date
Hydrographs generated by SynTerra, then modified by Duke Energy. Target elevations are 4-ft below CSL subgrade (5-ft below top of CSL), and based on NSLF revised
sump location (AECOM PTC Modification Request dated 12/14/2022). Page 2 of 2