20231101 Ver 1_More Info Received_20230912

September 12, 2023
Delivered via email to.' Brooke.A.Davis&usace.army..mil
Ms. Brooke Davis
Regulatory Project Manager
USACE Wilmington District -Asheville Regulatory Field Office
151 Patton Avenue, Room 208
Asheville, North Carolina 28801-5006
Re: Response to Reauest for Additional Information
Joint 404/401 Individual Permit Application
Duke Energy Unit 5 Inactive Ash Basin Dam Decommissioning Project, Cliffside
Steam Station
Cleveland and Rutherford Counties, North Carolina
USACE Action ID 2015-01426
Ms. Davis:
WSP USA Environment & Infrastructure, Inc. (WSP), on behalf of Duke Energy Carolinas, LLC
(Duke Energy), submitted a Joint Individual Permit (IP) application (package with USACE
EN4345 form and other documents) to the US Army Corps of Engineers (USACE) on August 7,
2023, for Duke Energy's Unit 5 Inactive Ash Basin (USIAB) Dam Decommissioning project
located at the Cliffside Steam Station in Cleveland and Rutherford Counties, North Carolina.
The submittal package and supporting documents for the IP application were also provided
to the North Carolina Department of Environmental Quality (NCDEQ) Division of Water
Resources (DWR) for Section 401 Individual Water Quality Certification.
Subsequently, on August 9, 2023, the USACE inquired via electronic mail to Mr. James Cutler
(WSP) and Ms. Lori Tollie (Duke Energy) if a pre -application meeting with the USACE had been
performed for the project. As a pre -application meeting had not been conducted for the
project, Mr. Sean Wallace (WSP) scheduled a pre -application meeting with you for August 18,
2023, to discuss the IP application with staff from WSP (Daniel Atkinson, Jan Gay, and Pam
Ferral), NCDEQ (Sue Homewood and Joey Winston), and Duke Energy (Lori Tollie, Preston
McCloud, and Shahid Rahu). During the pre -application meeting, the USACE and NCDEQ staff
requested additional information (RAI) on the project/proposed action to facilitate the USACE
and the NCDEQ review of the IP application. The agency comments/RAIs are recounted below,
along with the Duke Energy/WSP responses.
Item Number 1
Please provide additional details, figures, or information on the design of the proposed outfall
channel impacting Wetland C. Specifically, please provide responses to the following related
items:
• Provide a figure showing the five stormwater channels to be constructed for the
USIAB Dam Decommissioning project.

A description and/or figures of how the stormwater channels will be constructed (e.g.,
riprap, geotextile, size of riprap, etc.).
A figure showing Stream 7 and Stream 8 being reconnected to the Broad River with a
new channel design.
A discussion if natural stream design was evaluated for stormwater channels. Include
any constraints about the current channel design versus a natural channel design
such as costs, topography, soil substrate, structures, transmission lines, etc.
Item Number 1. Response:
The WSP engineering drawings titled: MAIN DAM (RUTHE-070, SCOPE 8) AND SADDLE DAM
(RUTHE-072, SCOPE 3) DECOMMISSIONING PLAN ROGERS ENERGYCOMPLEX- CLIFFSIDE
STEAM STATION PROPOSED FINAL GRADES (Stage 6) (Drawing No.'s CLS_C999.011.007,
CLS_C999.011.017, and CLS_C999.011.201) are attached and show the locations/extents of the
five proposed stormwater channels. Channels 1 through 4 are located within the USIAB
footprint and are designed to convey stormwater to the outlet channel, Channel 5. The outlet
Channel 5 is the downstream stormwater drainage feature that conveys stormwater to the
Broad River, after the Main Dam is removed. A riprap gabion outlet will be constructed at the
end of Channel 5 to convey stormwater down the riverbank and into the Broad River.
The five channels were designed for capacity and stability as trapezoidal channels to convey
runoff from the 100-year, 24-hour storm event. The riprap gabions were analyzed for capacity
and stability as a rectangular channel and the discharge calculated from Channel S. The
analyses results showed that the proposed channels and riprap gabion outlet have capacity
and stability to convey runoff from the 100-year, 24-hour storm event. However, the
calculated flow velocities were above the permissible velocities for vegetative lined open
channels. Due to varying slopes in Channels 1 and 3, different riprap channel linings are
proposed to keep tractive force within acceptable limits and varying slopes. In select areas
where the tractive force exceeded maximum permissible tractive force for gabion
mattresses, grouted riprap was selected as the channel lining.
Drawing No. CLS_C999.011.201 shows detailed designs for channel stabilization and THE
gabion outlet at the Broad River (see DETAIL 1 and 3). Drawing No. CLS_C999.011.017 presents
the longitudinal profile and proposed channel lining of each of the five proposed stormwater
channels (see DETAILS -5).
Drawing No. CLS_C999.011.007 also shows the locations of Stream 7 and Stream 8 and how
they will connect with the southern finger lobes of the USIAB area. Specifically, as proposed
under the Main Dam and Saddle Dam Decommissioning Plan, hydrological connections will
be established between Stream 7 and Channel 4 and between Stream 8 and Channel 3.
Natural stream design was not considered a viable option to transport and discharge
stormwater into the Broad River. The predominant soil map unit within the Main Dam area is
Udorthents, loamy, 0 to 15 percent slopes. A stream conveyance constructed within the project
area would exhibit a loss of channel stability, including undercutting, scouring, and bank
destabilization. The channel would cut back through the soft sediments. Furthermore, using
natural channel design would require the placement of many structures to protect the stream
banks and to maintain channel stability. Normally, in low velocity systems, wood structures
would be used; however, because of the soft sediments at the project site, rock would be
required to armor the stream channel. As such, the functional lift of the stream would be
reduced. For comparison, the final closure design of Channels 1 through 4 shows steep slopes
Duke Energy U51AB Dam Decommissioning Project, Cliffside Steam Station WSP
Cleveland and Rutherford Counties, North Carolina September 2023
Duke Energy Progress, LLC

requiring riprap, gabion baskets, or grouted riprap lining to convey design flows which will
prevent sediments from entering the water column.
Finally, it is noted that the U51AB closure final grades are based on the estimated bottom
(elevation) of ash that coincides with the topography of the area before the ash basin was
constructed. As such, the engineering design basis is to restore (mimic) the pre-existing
topography and surface water flow conditions of the area.
Item Number 2•
Please provide additional information on wetland avoidance and minimization for the
project/proposed action.
• Provide additional information regarding the effort (assessments) to avoid or reduce
impacts to Wetland C.
• Provide an updated Purpose and Need statement for the project.
Item Number 2 Response:
The proposed construction of the stormwater outfall Channel 5 to the Broad River will result
in a 0.9-acre impact to Wetland C. Possible change or shift in the outfall channel location to
the west or east of Wetland C (to avoid or reduce the wetland impact) was problematic. The
following points of discussion are presented:
• Transmission line rights -of -way presently exist along the eastern boundary of the
wetland and in the vicinity of the western boundary of the wetland.
• To the west of Wetland C, the existing higher topographic elevation constrains
moving the channel in this direction because it would require additional earthwork,
possible rock excavation and potentially relocating multiple transmission lines all of
which would significantly increase the cost of the project.
• The U51AB footprint (bottom elevation) coincides with the proposed locations of the
stormwater channels; therefore, additional fill material would be required under
construction activities to achieve positive flow of the stormwater channels
downstream to the Broad River.
• To the east of Wetland C, the existing higher topographic elevation constrains moving
the channel in this direction because it would require additional earthwork, possible
rock excavation and potentially relocating a transmission line all of which would
significantly increase the cost of the project.
• It is noted that Wetland M would not be impacted under the proposed action. The
proposed impacts to WOTUS are limited to only Wetland C and no other wetlands or
stream features within or outside of the U51AB and Main Dam areas would be
impacted.
Purpose and Need statement (updated):
The purpose of the project (proposed action) at the Cliffside Steam Station U51AB, with respect
to the authorization of fill impacts to WOTUS and issuance of an Individual Permit by the
USACE, is to establish a pathway to route clean stormwater post -development (i.e., following
the removal of CCR materials from the U51AB and the removal of the Main Dam) to the Broad
River, via the construction of five stormwater channels and the reconnection of two existing
Duke Energy U51AB Dam Decommissioning Project, Cliffside Steam Station WSP
Cleveland and Rutherford Counties, North Carolina September 2023
Duke Energy Progress, LLC

stream features (Streams 7 and 8) to an Outlet Channel at the Broad River. It is noted that the
proposed action would entail breaching and removing State Dam RUTHE-070 (Main Dam)
and, if required, State Dam RUTHE-072 (Saddle Dam) from the state dam inventory. Finally, the
proposed action would require the placement of fill material into WOTUS (Wetland C).
The purpose of the project is based on the need to address the North Carolina CAMA-14
regulatory requirements related to ash basin closure (i.e., U51AB) at the Cliffside Steam Station
and the disposal of CCR materials in a safe and timely manner.
The principal action that has accelerated the excavation and removal of CCR materials from
coal ash storage ponds (i.e., ash basins) at Duke Energy power generating plants with coal-
fired facilities is the promulgation of CAMA-14. Enacted on August 20, 2014, the bill requires
Duke Energy to phase out wet ash handling. As such, all coal ash in the state will be covered
by North Carolina's solid waste laws. In conjunction with CAMA-14, the NCDEQ has amassed
comprehensive data about coal ash facilities statewide. The information has been essential in
NCDEQ's prioritization of closure plans for the Duke Energy facilities with coal ash storage
ponds, including the Cliffside Steam Station (NCDEQ 2016). With these considerations, the
proposed action will address North Carolina regulatory requirements as related to ash basin
closure and disposal of CCR materials at the Cliffside Steam Station.
Item Number 3•
Please provide additional information on Wetland C; specifically, please provide the results of
an onsite re-evaluation of Wetland C, to be conducted by the WSP Professional Wetland
Scientist (PWS).
Item Number Response:
A WSP senior scientist/professional wetland scientist (PWS) conducted a site visit on August
30, 2023, to review Wetland C and assess its current condition. A new drainage channel along
the riverbank and within the northern boundary of the wetland was observed. The drainage
channel originates from a head-cut/remnant beaver dam in wetland C and flows through a
breach in the levee that allows for a direct hydrologic connection to exist between the
wetland and the river. A photograph of the drainage channel is included herein. The drainage
channel is linear, approximately three feet wide, and allows concentrated flows to the river
from Wetland C.
Item Number 4
Please provide additional information regarding the ash basin (U51AB) Coal Combustion
Residuals (CCR) materials disposal on site.
Response
The following statement was provided in the WSP Environmental Report (Sections 3.1 and
3.2): "Ash from the U51AB is transported to the on -site lined landfill. The on -site landfill is
located to the south of the U51AB across the Duke Power Road. Ash from the basin is
transported to the landfill with articulated trucks. The excavation of ash from the basin will be
completed prior to breaching the Main Dam and, if required, the Saddle Dam. Soil from the
dam removal will be used for restoration grading within the U51AB area and used for on -site
landfill operations and closure. Soil will go directly to the landfill operations, closure, or be
Duke Energy U51AB Dam Decommissioning Project, Cliffside Steam Station WSP
Cleveland and Rutherford Counties, North Carolina September 2023
Duke Energy Progress, LLC

stockpiled adjacent to the landfill in approved stockpile locations covered by existing E&SC
Plans".
For the USIAB Dam Decommissioning project at the Cliffside Steam Station, no temporary or
permanent impacts to WOTUS (wetlands and streams) will be made within or outside the
project LOD, other than the proposed 0.9-acre impact to Wetland C at the Broad River for the
construction of Channel 5 (downstream outlet channel). In addition, Duke Energy/WSP verified
that there are no additional work areas and/or staging areas outside the projects' LOD.
Duke Energy/WSP appreciates your attention to this project. If you have any questions or
comments, or need additional information, please contact me at [phone], Mr. Sean
Wallace at [phone] and/or Ms. Lori Tollie (Duke Energy) at [phone].
Sincerely,
WSP USA Environment & Infrastructure Inc.
James D. Cutler, PWS
Senior Scientist
Sean R. Wallace, PMP, PWS
Associate Scientist
Attachments: USACE RAI Response —Attach ments_9-12-23
Cc: Sue Homewood (NC Division of Water Resources)
Joey Winston (INC Division of Water Resources)
Lori Tollie (Duke Energy)
Preston McCloud (Duke Energy)
Shahid Rahu (Duke Energy)
Ken Daly (WSP)
Basak Gulec-Dincer (WSP)
Jan Gay (WSP)
Duke Energy U51AB Dam Decommissioning Project, Cliffside Steam Station WSP
Cleveland and Rutherford Counties, North Carolina September 2023
Duke Energy Progress, LLC

5
REV.
Is
M
o
o
F
o r /C
NOTE THAT GRADING OF OUTLET CHANNEL j aMw
(CHANNEL 5) AND BROAD RIVER TIE IN ARE // Mw
SUBJECT TO CHANGE BASED ON USACE AND
/ NCDEQ WETLANDS PERMITTING. /
BROAD RIVER
% _ - ----
3 \
.........................
v _ _ sassoo _
...............�� ' / \ \ \\\\ \ 014 �f. I / 1 �/ 730
— FOR BASIN OUTLET AREA, SEE DRAWING
CLS_C999.011.013 FOR MORE DETAIL
Z"Q\
CHANNEL 5
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STREAM 8 IIII
/ \�
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1 08/28/2023 7818220026 DAM DECOMMISSIONING TJK SLS TJK BIG KRD
0 04/17/2023 7818220026 DAM DECOMMISSIONING BAM BAM TJK BIG KRD
REV DATE JOB NO. PROJECT TYPE DES DFTR CHKD ENGR APPD
INCHES 1 2 3 TENTHS 10 20 30 4 5 6
N
150 0 150 300 FT
A
NOTE:
1. THE "APPROXIMATE LIMITS OF ASH BASIN FACILITY BOUNDARY"
AND THE "APPROXIMATE LIMITS OF CCR BOUNDARY" ARE
BASED ON AERIAL PHOTOGRAPHY, TOPOGRAPHIC MAPPING,
AND OTHER HISTORICAL DRAWINGS AND INFORMATION AND
SHOULD BE CONSIDERED APPROXIMATE. THE "APPROXIMATE
LIMITS OF ASH BASIN FACILITY BOUNDARY" INCLUDES THE
CONTAINMENT DAMS AND DIKES WHILE THE "APPROXIMATE
LIMITS OF CCR BOUNDARY" EXCLUDES THOSE STRUCTURES
AND IS BASED ON UPDATED TOPOGRAPHIC MAPPING,
REPORTED OPERATIONAL LEVELS, AND SUBSURFACE DATA
COLLECTED WITHIN THE BASIN. IT SHOULD BE NOTED THAT
THE DETERMINATION OF THE ACTUAL LATERAL EXTENT OF THE
CCR MATERIALS WILL TAKE PLACE PRIOR TO, AND/OR DURING,
IMPLEMENTATION.
2. THE PROPOSED FINAL GRADES WERE OBTAINED FROM CCR
SURFACE IMPOUNDMENT CLOSURE PLAN PREPARED FOR THE
INACTIVE UNIT 5 ASH BASIN, DRAWING CLS_C9XX.OXX.010
DATED MARCH 18 2021 PREPARED BY WOOD (WSP).
REFERENCES:
1. ASH BASIN FACILITY BOUNDARIES PROVIDED BY DUKE
ENERGY.
2. EXISTING TOPOGRAPHIC INFORMATION WAS PRODUCED FROM
PHOTOGRAMMETRIC METHODS FROM AERIAL PHOTOGRAPHY
OBTAINED ON JULY 31, 2015 BY WSP. MAIN DAM DOWNSTREAM
AREA EXISTING CONDITIONS TOPOGRAPHIC SURVEY WAS
DONE BY FLEMING ENGINEERING INC. (FEI) ON FEBRUARY 16
AND 17, 2023.
m
\ \c
TIT'�AIN DAM (RUTHE-070, SCOPE 8) AND SADDLE DAM
(RUTHE-072, SCOPE 3) DECOMMISSIONING PLAN
ROGERS ENERGY COMPLEX - CLIFFSIDE STEAM STATION F
WSP USA ENVIRONMENT ROAD, UITE10UREINC. PROPOSED FINAL GRADES (STAGE 6)
2801 YORKMONT ROAD, SUITE 100
CHARLOTTE, NC 28208
TEL. [phone]
FOR
N.C. ENG. LICENSURE: F-1253 ISSUED FOR REVIEW
j %///%flllll o SEAL SCALE: AS SHOWN DES: BAM
DUKE DWG TYPE: DWG DFTR: BAM
JOB NO: 7818220026 CHKD: TJK
III 1 II III IIII I ISSUED FOR ENE RGY DATE: 8/28/2023 ENGR: BG
o/I
FILENAME: CLS_C999.011.007 PROPOSED FINAL GRADES (STAGE 5) APPD: KRD
REVIEW DWG SIZE DRAWING NO. REVISION
ISSUED FOR REVIEW ANSI D C LS C999.011.007 1
ISSUED FOR PERMITTING 22'�X34��
DESCRIPTION
7 8 9 110

I
7
REV. 1
L
IV
E
F
755
750
745
740
735
730
725
720
715
710
705
700
695
690
685
680
675
670
668
755
750
745
740
735
730
725
720
715
710
705
700
695
690
685
680
675
670
668
3+00 3+50 4+00 4+50 5+00 5+50 6+00 6+50 7+00 7+50 8+00 8+50 9+00 9+50 10+00 10+50 11+00 11+50 12+00 12+50 13+00 13+50 14+00 14+50 15+00 15+50 16+00 16+50 17+00
680
675
670
668
22+00 22+50 23+00 23+50 24+00 24+50 25+00 25+50 26+00 26+50 27+00 27+50
MAXIMUM SLOPE:-15.89%
(STA 15+18.99 - 5+20.36)
I7 M f-%rif-%or!r% CIAIAI flMAnC
CHANNEL 1
�17HORIZONTAL SCALE: 1" = 100'
VERTICAL SCALE: I = 30'
770
765
760
755
750
745
740
735
730
725
720
715
710
705
700
695
690
685
680
675
672
2 CHANNEL 2
�17HORIZONTAL SCALE: 1" = 100'
VERTICAL SCALE: 1" = 30'
'tttb.
MAXIMUM SLOPE:
-14.44% BETWEEN
STA 1 +92.33 - 1 +97.32
I
PROPOSED FINAL
GRADE BOTTOM OF
CHANNEL EXTENSION
680
675
670
668
0+00 0+50 1+00 1+50 2+00 2+50 3+00 3+50 4+00 4+50 5+00 5+50 6+00 6+50 7+00 7+50 8+00 8+50 9+00
800
795
790
785
780
775
770
768
800
795
790
785
780
775
770
768
0+00 0+50 1+00 1+50 2+00 2+50 3+00
4 CHANNEL 4
�17HORIZONTAL SCALE: 1" = 100'
VERTICAL SCALE: 1" = 30'
PROPOSED FINAL GRADE BOTTOM OF
CHANNEL (GRADES TO BE DETERMINED)
GABION BASKETS AT OUTER EDGE
27+50 28+00 28+50 29+00 29+50 30+00
5 CHANNEL 5
�17HORIZONTAL SCALE: 1" = 100'
VERTICAL SCALE: 1" = 30'
INCHES 1 2 3 ITENTHS 10 20
Channel ID
Channel Lining
Maximum Allowable
Slope
113
Grouted Riprap
N/A
1R
Gabion Mattress
7.91%
1R
Class 2 Riprap
2.87%
1R
Class 1 Riprap
1.93%
1R
Class B Riprap
1.48%
1R
class Riprap
0.60%
770
765
760
755
750
745
740
735
730
PROPOSED FINAL 725
GRADE BOTTOM OF 720
CHANNEL
715
710
705
700
695
690
685
680
675
672
9+50 10+00 10+50 11+00 11+50 12+00 12+50 13+00 13+50 14+00 14+50 15+00 15+50 16+00 16+50 17+00 17+50 18+00 18+50 19+00 19+50 20+00 20+50 21+00 21+5C21+86
3 CHANNEL 3
�17HORIZONTAL SCALE: 1" = 100'
VERTICAL SCALE: 1" = 30'
--1 4
30
Channel ID
Channel Lining
Maximum Allowable
Slope
311
Grouted Riprap
N/A
3R
Gabion Mattress
13.19%
3R
Class 2 Riprap
4.43%
311
Class 1 Riprap
2.95%
3R
Class B Riprap
2.25%
3R
Class A Riprap
0.85%
CHANNEL LINING LEGEND
GROUTED RIPRAP
GABION MATTRESS
CLASS 2 RIPRAP
CLASS 1 RIPRAP
CLASS B RIPRAP
CLASS A RIPRAP
REFERENCES:
1. STORMWATER CHANNEL CAPACITY AND STABILITY CALCULATIONS FOUND IN CALCULATION PACKAGE
TITLED 'CHANNEL AND DAM BREACH CALCULATION' DATED AUGUST 28, 2023.
2. OTHER CHANNEL LININGS WITH EQUIVALENT PERFORMANCE CAN ALSO BE USED FOR THE PROPOSED
CHANNELS.
3. CHANNEL 5 ALIGNMENT IS SUBJECT TO CHANGE BASED ON USACE AND NCDEQ WETLANDS PERMITTING.
4. SEE DRAWING CLS_C999.011.201 FOR CHANNEL GEOMETRY AND STABILIZATION DETAILS.
W
7D
rF,
TITLE
MAIN DAM (RUTHE-070, SCOPE 8) AND SADDLE DAM
(RUTHE-072, SCOPE 3) DECOMMISSIONING PLAN
ROGERS ENERGY COMPLEX - CLIFFSIDE STEAM STATION F
WSP USA ENVIRONMENT & INFRASTRUCTURE INC.
2801 YORKMONT ROAD, SUITE 100
CHARLOTTE, NC 28208
TEL. [phone]
N.C. ENG. LICENSURE: F-1253
CHANNEL PROFILES
FOR
ISSUED FOR REVIEW
SEAL
ISSUED FOR
REVIEWFILENAME:
4�
DUKE
�' N E RGYF
SCALE: AS SHOWN
DES:
BAM
-DWG TYPE: DWG
DFTR:
BAM
NO: 7818220026
CHKD:
TJK
DATE 8/28/2023JOB
ENGR:
BG
CLS_C999.011.016 CHANNEL PROFILES APPD:
DWG SIZE DRAWING NO. REVISION
KRD
ANSI D
22"x34"
C L S C999.011.017
—
1
1
08/28/2023
7818220026
DAM DECOMMISSIONING
TJK
SLS
TJK
BG
KRD
ISSUED FOR REVIEW
0
04/17/2023
7818220026
DAM DECOMMISSIONING
BAM
BAM
TJK
BG
KRD
ISSUED FOR PERMITTING
REV
DATE
JOB NO.
PROJECT TYPE
DES
DFTR
CHKD
ENGR
APPD
DESCRIPTIONI
5 6 7
8
9
10
I

3
I
5 6 7
1 IREV1
E
F
T
Z2 L Z1
B
GROUTED RIPRAP/GABION MATTRESS/RIPRAP
VARIES
n�r�d
DMAX X 1.5
8 OZ/SY NON -WOVEN GEOTEXTILE
EXISTING GRADE
3-FT. X 3-FT. X 9-FT. LONG
GABION BASKET
PROJECTED TOP OF
GABION BASKETS
FLOW LINE OF
OUTLET DITCH
8 OZ/SY NONWOVEN GEOTEXTILE -`
18-IN. THICK GABION MATTRESS
6-IN. NCDOT NO. 57 STONE CUSHION LAYER
8 OZ/SY NONWOVEN GEOTEXTILE
Legend
T=
Top Width
B=
Bottom Width
D=
Depth
Z1=
Right Side Slope
Z2=
Left Side Slope
Channel Geometry
Channel
ID
Channel
Depth
{D) (ft)
Bottom
Width
{B) (ft)
Top
Width
{T) (ft)
Left Side
Slope
{Z,H:V)
Right Side
Slope
{ZZH:V)
1R
3
10
28
3
3
2R
3
10
28
3
3
3R
3
30
54
3
3
4R
2
5
17
3
3
5R
2
30
42
3
3
Riprap Size Gradation
Graded Rock Size
(inches)
Classor#
Maximum
D50
Minimum
A
6
4
2
B
12
8
5
1
17
10
5
2
23
14
9
CHANNEL STABILIZATION DETAIL
N.T.S.
3.0'
1.5'
O 3.0'
_711-
18-IN. THICK GABION MATTRESS
6-IN. NCDOT NO. 57 STONE CUSHION LAYER
8 OZ/SY NONWOVEN GEOTEXTILE
42'
TYPICAL GABION OUTLET SECTION
3.0'
\
\
\
�O \
o \
O� v
o Oo \
TYPICAL GABION OUTLET PROFILE
3 GABION OUTLET DETAIL
.201 N.T.S.
INCHES 1 2 3 TENTHS 10 20 30 4
4' X 4' X 4' DEEP PRECAST CONCRETE
X DROP INLET (SEE NOTE 1)
4'
a
a
a
a
ad
d
�d
a
d
a
d�
a
a
a
a
a
d
d
a
a
a
d
�
X
BROAD RIVER WATER
SURFACE AT TIME OF
CONSTRUCTION
EXISTING GRADE
1 08/28/2023 7818220026 DAM DECOMMISSIONING TJK SLS TJK BG KRD
0 04/17/2023 7818220026 DAM DECOMMISSIONING BAM BAM TJK BG KRD
REV DATE JOB NO. PROJECT TYPE DES DFTR CHKD ENGR APPD
5 6
4'
q
^' " ^' V A' DEEP PRECAST CONCRETE
ILET (SEE NOTE 1)
30" DIA. DUAL WALL HDPE PIPES
(ADS N-12 WT OR APPROVED EQUIVALENT)
SECTION X-X
NOTES:
1. INSTALL PRECAST CONCRETE DROP INLET AND GRATES IN ACCORDANCE WITH NCDOT SPECIFICATIONS.
2. DROP INLET DIMENSIONS MAY BE OPTIMIZED FOR FIELD CONDITIONS.
30" DIA. DUAL WALL HDPE PIPES
(ADS N-12 WT OR APPROVED EQUIVALENT)
PRECAST CONCRETE DROP INLET
NOT TO SCALE
7"
rm
G
TITLE
MAIN DAM (RUTHE-070, SCOPE 8) AND SADDLE DAM
(RUTHE-072, SCOPE 3) DECOMMISSIONING PLAN
ROGERS ENERGY COMPLEX — CLIFFSIDE STEAM STATION
DETAILS 1
F
WSP USA ENVIRONMENT & INFRASTRUCTURE INC.
2801 YORKMONT ROAD, SUITE 100
CHARLOTTE, NC 28208
TEL. [phone]
N.C. ENG. LICENSURE: F-1253
FOR
ISSUED FOR REVIEW
SEAL
ISSUEDFOR
REVIEW
CfDUKE
.!�JOB
ENEnt"**%/F
SCALE: AS SHOWN
DES: BAM
DWG TYPE: DWG
DFTR: BAM
NO: 7818220026
CHKD: TJK
DATE: 8/28/2023
ENGR: BG
FILENAME: CLS_C999.011.201 DETAILS 1 APPD: KRD
DWG SIZE DRAWING NO. REVISION
ANSI D
22"X34"
C L S C999.011.201 1
ISSUED FOR REVIEW
ISSUED FOR PERMITTING
DESCRIPTION
7 8 9 10

Cliffside USIAB Dam Decommissioning Project September 6, 2023
Project No.7818230105 Rutherford and Cleveland Counties, NC
Prepared By: JDC
Checked By: PM "
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