NC0003425_2020-04-16 Duke Energy Roxboro CAP Update Addendum_20200416

DUKE
ENERGY®
April 16, 2020
Ms. Sheila Holman
Assistant Secretary for Environment
North Carolina Department of Environmental Quality
1611 Mail Service Center
Raleigh, North Carolina 27699-1611
Paul Draovitch
Senior Vice President
Environmental, Health & Safety
526 S. Church Street
Mail Code: EC3XP
Charlotte, NC 28202
[phone]
Subject: Corrective Action Plan Update Addendum
Demonstration of 02L Compliance for the East Ash Basin by December 31, 2029
Roxboro Steam Electric Plant
Person County, North Carolina
Dear Ms. Holman:
The attached memorandum prepared by SynTerra Corporation on behalf of Duke Energy,
includes revisions to the Roxboro Steam Electric Plant (Roxboro) corrective action strategies
presented in Appendix G, "Updated Groundwater Flow and Transport Modeling Report," of the
Roxboro Corrective Action Plan (CAP) Update (SynTerra, 2019) submitted to the Department
on December 30, 2019.
The compliance boundary showing a buffer of 500-feet from waste and wastewater boundaries
was utilized in the CAP for flow and transport modeling and design of a corrective action system
able to remediate groundwater constituents of interest (COls) attributable to the East Ash Basin
(EAB) to concentrations less than the North Carolina Administrative Code (NCAC), Title 15A,
Subchapter 02L, Groundwater Classification and Standards (02L) standard by December 31,
2029.
A Consent Order (CO) that specifies obligations related to the closure of coal ash
impoundments and groundwater corrective action at six Duke Energy coal combustion sites in
North Carolina, including Roxboro was signed on February 5, 2020. The CO requires COls
attributable to the Roxboro ash basins be remediated to concentrations less than the 02L
standard by December 31, 2029 at or beyond the Geographic Limitation. The Geographic
Limitation is defined in the CO as 500 feet from the ash basin waste boundary, at the property
boundary, or the boundary of a water body, whichever is closer.
The boundary for flow and transport modeling and design of the corrective action system for the
EAB was revised such that the eastern discharge canal 500-foot buffer is no longer used for
future 02L compliance. Modeling with the Geographical Limitation boundary indicated the need
for nine additional extraction wells northwest of the EAB to remediate groundwater constituents
of interest (COls) attributable to the EAB to concentrations less than the 02L standard by
December 31, 2029.

Ms. Sheila Holman
April 13, 2020
Corrective Action Plan Update Addendum
Roxboro Steam Electric Plant
Page 2
Corrective action modeling for this Roxboro CAP Update addendum assumes that groundwater
remediation activities will begin in 2021 and compliance will be achieved by December 31,
2029.
This submittal is only being sent electronically. Please contact Kimberlee Witt at (336) 215-
4576 or [e-mail] if you have any questions or need additional
information.
Sincerely,
Paul Draovitch
Senior Vice President
Environmental, Health & Safety
Enclosure:
Corrective Action Plan Addendum - Demonstration of 02L Compliance for the Roxboro
East Ash Basin by December 31, 2029 (SynTerra Corporation, April 13, 2020)
[910
NCDEQ
- Rick Bolich
NCDEQ
- Steve Lanter
NCDEQ
- Eric Smith
NCDEQ
- Eric Rice
NCDEQ - Ted Campbell (MODFLOW Data Files)
NCDEQ
- Elizabeth Werner (MODFLOW Data Files)

410
synTerra TECHNICAL MEMORANDUM
Date: April 13, 2020 File: 1026.600.12
To: Scott Davies (Duke Energy)
Kimberly Witt (Duke Energy)
From: Rong Yu, Ph.D. (SynTerra) R Y
Johnathan Ebenhack (SynTerra)
Craig D. Eady, LG (SynTerra)
Subject: Corrective Action Plan Addendum - Demonstration of 02L Compliance for
the Roxboro East Ash Basin by December 31, 2029
SynTerra prepared this technical memorandum for Duke Energy to demonstrate that
groundwater constituents of interest (COIs) associated with the East Ash Basin (EAB) at
the Roxboro Steam Electric Plant (Roxboro, Site) can be remediated beyond the ash
basin Geographic Limitation to concentrations less than North Carolina Administrative
Code (NCAC), Title 15A, Subchapter 02L, Groundwater Classification and Standards (02L)
by December 31, 2029.
This memorandum includes revisions to the corrective action strategies presented in
Appendix G, "Updated Groundwater Flow and Transport Modeling Report," of the
Roxboro Corrective Action Plan (CAP) Update (SynTerra, 2019).
Background
Duke Energy, the North Carolina Department of Environmental Quality (NCDEQ), and
11 community groups entered into a Settlement Agreement (SA) on December 31, 2019.
A Consent Order (CO) to address the SA was finalized on February 5, 2020. The CO
specifies obligations related to the closure of coal ash impoundments at six Duke
Energy coal combustion sites in North Carolina, including the Roxboro site in Semora,
Person County. The CO further describes obligations related to groundwater corrective
action plans that apply to those six sites. A specified obligation at Roxboro is that COIs
attributable to the ash basins be remediated at or beyond the Geographic Limitation to
concentrations less than the 02L standard by December 31, 2029. The Geographic
Limitation is defined in the CO as 500 feet from the ash basin waste boundary, at the
property boundary, or the boundary of a water body, whichever is closer.
The compliance boundary used in the flow and transport report (Appendix G) and
presented in the CAP Update submitted to the NCDEQ on December 31, 2019 included
a 500-foot buffer zone for the EAB eastern discharge canal based on Duke Energy's legal
interpretation of the compliance boundary in this area. Under the CO, the compliance
boundary was replaced with a Geographic Limitation, which was based on a 500-foot
Page 1

Demonstration of 02L Compliance for the
Roxboro East Ash Basin by December 31, 2029 April 13, 2020
Roxboro Steam Electric Plant
distance from the ash basin waste boundary. Figure 1 attached provides a comparison
of the compliance boundary presented in the CAP Update and the Geographic
Limitation stipulated by the CO.
The revised corrective action approach presented in this memorandum assumes a
Geographic Limitation consistent with the CO and does not include a 500-foot buffer
around the EAB discharge canal. The corrective action demonstration follows the same
format as Appendix G in the CAP Update and is consistent with the methodology used
to evaluate remedial options. Corrective action modeling for this demonstration
assumes that remediation activities will begin in February 2021 and compliance will be
achieved by December 31, 2029.
Revised Corrective Action Plan Design
A revised groundwater corrective action approach to achieve compliance with the
respective 02L standards for boron, sulfate, and total dissolved solids (TDS) by
approximately December 31, 2029, has been simulated based on the new Geographic
Limitation. The simulation uses COI distributions estimated for February 2021 as initial
conditions. The revised corrective action occurs northeast of the EAB (Figure 2). The
corrective action methodology for the EAB includes groundwater extraction methods to
capture COI that have migrated from CAMA-regulated sources (i.e., EAB) beyond the
Geographic Limitation.
The CAP Update also included designs to create a hydraulic barrier to prevent the
migration of COIs from sources not regulated by CAMA (Figure 3). The design for this
area is not affected by the new Geographic Limitation for the EAB.
The revised CAP design includes up to nine additional vertical groundwater extraction
wells at the northeast corner of the EAB resulting from the Geographic Limitation
change (Figure 2). The actual number and location of extraction wells installed may be
adjusted based on field data collected in the area during the pilot testing phase. The
proposed vertical extraction wells will have depths that range from approximately 470
feet below ground surface (bgs) to 510 feet bgs. The extraction wells will target COIs
that might be present in the deeper bedrock fractures in that area.
The revised combined groundwater remediation system for CAMA-regulated and
sources not regulated by CAMA consists of up to 59 groundwater extraction wells and
27 clean water infiltration wells. The extraction wells are modelled at an average
extraction rate of 1.7 gallons per minute (gpm) and the clean water infiltration wells are
modelled with an average flow rate of 2.8 gpm (Table 1 and Figure 2). As discussed in
Appendix G, the extraction wells are simulated using vertical arrays of drain points in
Page 2

Demonstration of 02L Compliance for the
Roxboro East Ash Basin by December 31, 2029 April 13, 2020
Roxboro Steam Electric Plant
MODFLOW. The drain bottom elevations are set to the center of each grid block
containing the drain. This simulates a condition where the groundwater is being
pumped out of the well casing to maintain a water level near the bottom of the well.
The drain conductance values are estimated by considering radial flow to a well, based
on the Anderson and Woessner (1992) approach. For a horizontal hydraulic
conductivity of K, a well radius of rW, and horizontal and vertical grid spacing of Ax and
Az, the drain conductance ( C ) for a grid block is computed as:
C = E,,,
21-rKAz
In 0.208Ax
r
W
where EW is the well efficiency, which accounts for well skin effects. A well efficiency of
Ew = 0.5 was used for the extraction wells.
Results
The simulations indicate that the cluster of up to nine additional extraction wells create
a cone of depression marked by closed head contours to address COIs at or beyond the
Geographic Limitation as shown in Figure 3.
The analysis was conducted using two parallel scenarios, one where sources not
regulated by CAMA are absent and another where those sources are left in place
(Figure 4a). One scenario omits sources not regulated by CAMA from the simulation
and shows the COI concentrations greater than the 02L standard associated with the
EAB. The other scenario shows COI concentrations resulting from additional,
downgradient sources at the Site.
Results from the simulations show that the 41 extraction wells associated with the
CAMA-regulated EAB, including up to nine new wells, can achieve 02L compliance
along the EAB Geographic Limitation by December 31, 2029 (Figure 4b).
Detailed Cost Estimate
A detailed cost estimate for nine additional extraction wells is provided in the attached
table (Table 1) as part of Appendix K of the CAP Update. The cost estimate is based on
capital costs for design and implementation, the O&M cost, and monitoring costs,
including well redevelopment and replacement on an annual basis. The design costs
include work plans, design documents and reports necessary for implementation of the
alternative. Implementation costs include procurement and construction. O&M costs
are based on annual routine labor, materials and equipment to effectively conduct
Page 3

Demonstration of 02L Compliance for the
Roxboro East Ash Basin by December 31, 2029 April 13, 2020
Roxboro Steam Electric Plant
monitoring, routine annual and 5-year reporting, as applicable, and routine and non -
routine maintenance costs.
Conclusion
The following conclusions are based on the results of the revised corrective action
simulations:
• The revised corrective action approach is capable of reducing modeled COI
concentrations related to the EAB to less than 02L at the Geographic Limitation
by December 31, 2029.
• The proposed starting date of remediation activities is conceptual at this time.
The fully operational date depends on permitting and construction schedules.
References
SynTerra (2019). Corrective Action Plan (CAP) Update, Roxboro Steam Electric Plant, 1700
Dunnaway Road, Semora, North Carolina.
Anderson, M.P., & Woessner, W.W. (1992). Applied Groundwater Modeling, Simulation of
Flow and Advective Transport. (p. 381). New York City, NY: Academic Press, Inc.
Page 4

Demonstration of 02L Compliance for the
Roxboro East Ash Basin by December 31, 2029 April 13, 2020
Roxboro Steam Electric Plant
FIGURES

*.
OfiJ11Y�'
a
LEGEND
�' DUKE
340 GRAPHIC SCALE
0 340 680
� ENERGY
(IN FEET)
ASH BASIN WASTE BOUNDARY
PROGRESS
DRAWN Br. R.YU DATE: 02/04/2020
ASH BASIN COMPLIANCE BOUNDARY DEPICTED
IN CAP
REVISED BY: R.YU DATE: 04/03/2020
UPDATE REPORT (SYNTERRA, 2019)
CHECKED BY: C. EADY DATE: 04/03/2020
10
APPROVED BY: C. EADY DATE: 04/03/2020
GEOGRAPHIC LIMITATION
PROJECT MANAGER: C. EADY
— EFFLUENT DISCHARGE CANAL
synTerra
www.synterracorp.com
NOTES:
FIGURE 1
ALL BOUNDARIES ARE APPROXIMATE.
COMPARISON BETWEEN COMPLIANCE BOUNDARY
AERIAL PHOTOGRAPHY OBTAINED FROM ESRI ON DECEMBER 4,2019. AERIAL WAS
AND GEOGRAPHIC LIMITATION
COLLECTED ONFEBRUARY6,2017.
UPDATED GROUNDWATER FLOW AND TRANSPORT MODELING REPORT
CDRAWING HAS BEEN SET OORDINATE SYSTEM RIPS NORTH CAROLINA STATE PLANE
STEM FPS3200(NAD 3AND NAVD8
TECHNICAL MEMORANDUM
ROXBORO STEAM ELECTRIC PLANT

e
GRAPHIC SCALE
F-
'ti
100 0 100 200
%' DUKE GRAPHIC SCALE
340 0 340 680
LEGEND
EXTRACTION WELLS
ENERGY
(IN FEET)
NINE (9)ADDITIONAL EXTRACTION WELLS
PROGRESS DRAWN BY: R.YU DATE:02/04/2020
CLEAN WATER INFILTRATION WELLS
REVISED BY: R. YU DATE: 04/11/2020
CHECKED BY. C. EADY DATE: 04/11/2020
'41�
ASH BASIN WASTE BOUNDARY
APPROVED BY: C. EADY DATE: 04/11/2020
PROJECT MANAGER: C. EADY
- — GEOGRAPHIC LIMITATION
synTerra
www.synterracorp.com
NOTES:
FIGURE 2
ALL BOUNDARIES ARE APPROXIMATE.
ACTIVE GROUNDWATER REMEDIATION SYSTEM
THE REMEDIATION SYSTEM SHOWN WAS DESIGNED FOR 02L COMPLIANCE BY 2029.
NORTHEAST AREA OF THE EAST ASH BASIN
AERIAL PHOTOGRAPHY OBTAINED FROM ESRI ON DECEMBER 4,2019. AERIAL WAS
UPDATED GROUNDWATER FLOW AND TRANSPORT MODELING REPORT
COLLECTED ONFEBRUARY6,2017.
TECHNICAL MEMORANDUM
DRAWING HAS BEEN SET WITH PROJECTION OF NORTH CAROLINA STATE PLANE
COORDINATE SYSTEM RIPS 3200(NAD83 AND NAVD88).
�/
ROXBORO STEAM ELECTRIC PLANT
SEMORA, NORTH CAROLINA

420
o g2o 420 420 �10 �10
420
410
ra•-.. ���
4�0
O
r
4y0 .
• 460 0
• p10 : A3� T v
I 'A
0
4g0 Lo A60 v
■
EAST ASH
M 490 48p
�• BASIN •
410 i
D 390 �w g .
480
Q 490
v v v a m boo 00 500 ✓ `� 1 , � .
O
A6'O O rj. �� S � • �
00
GRAPHIC SCALE y ��
100 0 100 200
460
LEGEND t
DUKE GRAPHIC SCALE
340 0 340 680
EXTRACTION WELLS ENERGY (IN FEET)
O NINE (9)ADDITIONAL EXTRACTION WELLS PROGRESS DRAWN BY: R.YU DATE: 02/04/2020
♦ CLEAN WATER INFILTRATION WELLS 111,1 REVISED BY: R.YU DATE: 04/11/2020
HYDRAULIC HEAD FEET CHECKED BY: C. EADY DATE: 04/11/2020
(FEET) APPROVED BY: C. EADY DATE: 04/11/2020
ASH BASIN WASTE BOUNDARY WnTerra PROJECT MANAGER: C. EADY
GEOGRAPHIC LIMITATION www.synterracorp.com
NOTES:
FIGURE 3
ALL BOUNDARIES ARE APPROXIMATE. SIMULATED HYDRAULIC HEADS IN UPPER FRACTURED BEDROCK ZONE
CONTOUR INTERVAL IS IO FEET. HEADS ARE SHOWN AFTER CLOSURE -IN -PLACE FOR MODEL LAVER 16. WITH ACTIVE GROUNDWATER REMEDIATION
THE REMEDIATION SYSTEM SHOWN WAS DESIGNED FOR 02L COMPLIANCE BY 2029. UPDATED GROUNDWATER FLOW AND TRANSPORT MODELING REPORT
AERIAL PHOTOGRAPHY OBTAINED FROM ESRI ON DECEMBER 4,2019. AERIAL WAS TECHNICAL MEMORANDUM
COLLECTED ONFEBRUARY6,2017. ROXBORO STEAM ELECTRIC PLANT
COORDINATEDRAWING HAS BEEN SET SYIC8)THCAROLINASTATE PLANE
SYSTEM RIPS 3200(NAD 3ANDNAVD8SEMORA, NORTH CAROLINA

IMULATED WITHOUT NON-CAMA CCR SOURCES
I^ JJJrJJJ JA
t �
EASTASH BASIN
MSIMULATED WITH NON-CAMA CCR SOURCES
Pq[
r
EAST ASH BASIN
LEGEND
■ REFERENCE LOCATION
NON-CAMA CCR SOURCE ZONES NOT SUBJECT TO THE
12/31/2029 02L COMPLIANCE DEADLINE. THESE AREAS WILL
OBE ADDRESSED BY THE PLANNED REMEDIATION SYSTEM IN
THE GYPSUM STORAGE AREAAND FUTURE EXCAVATION
BORON 700 - 4,000 Ng/L
BORON > 4,000 Ng/L
ASH BASIN WASTE BOUNDARY
GEOGRAPHIC LIMITATION
ALL BOUNDARIES ARE APPROXIMATE.
NON-CAMACCR SOURCES INCLUDE THE GSAIDFAHA SOURCES TO THE NORTH OF EAB.
AERIAL PHOTOGRAPHY OBTAINED FROM ESRI ON DECEMBER 4, 2019. AERIAL WAS COLLECTED ON FEBRUARY 6,
2017.
DRAWING HAS BEEN SET WITH PROJECTION OF NORTH CAROLINA STATE PLANE COORDINATE SYSTEM FI PS 3200
(NAD83).
�.�.�C.
1_
DUKE
tn
GRAPHIC SCALE
340 0 340 680
ENERGY
(IN FEET)
PROGRESS
DRAWN BY: R.YU
REVISED BY: R. YU
DATE: 02/04/2020
DATE: 03/30/2020
1��
CHECKED BY: C. EADY
DATE: 03/30/2020
APPROVED BY: C. EADY
DATE: 03/30/2020
PROJECT MANAGER: C. EADY
FIGURE 4a
SIMULATED APRIL 2019 MAXIMUM BORON CONCENTRATIONS
IN ALL NON -ASH LAYERS
DOWNGRADIENT OF THE EAST ASH BASIN
UPDATED GROUNDWATER FLOW AND TRANSPORT
MODELING REPORT
TECHNICAL MEMORANDUM
ROXBORO STEAM ELECTRIC PLANT
SEMORA, NORTH CAROLINA

IMULATED WITHOUT NON-CAMA CCR SOURCES
EAST ASH BASIN
SIMULATED WITH NON-CAMA CCR SOURCES
♦ }
�'11-001
a•
EAST ASH BASIN
LEGEND
EXTRACTION WELLS
0 NINE (9) ADDITIONAL EXTRACTION WELLS
♦ CLEAN WATER INFILTRATION WELLS
IN REFERENCE LOCATION
NON-CAMA CCR SOURCE ZONES NOT SUBJECT TO THE 12/31/2029 02L
COMPLIANCE DEADLINE. THESE AREAS WILL BE ADDRESSED BY THE
PLANNED REMEDIATION SYSTEM IN THE GYPSUM STORAGE AREAAND
FUTURE EXCAVATION
BORON 700 - 4,000 Ng/L
M BORON > 4,000 Ng/L
ASH BASIN WASTE BOUNDARY
-GEOGRAPHIC LIMITATION
ALL BOUNDARIES ARE APPROXIMATE.
CLOSURE -BY -EXCAVATION SCENARIO IS ESTIMATED TO BE COMPLETED IN YEAR 2037.
NON-CAMACCR SOURCES INCLUDE THE GSA/DFAHA SOURCES TO THE NORTH OF EAB.
AERIAL PHOTOGRAPHY OBTAINED FROM ESRI ON DECEMBER 4, 2019. AERIAL WAS COLLECTED ON FEBRUARY 6,
2017.
DRAWING HAS BEEN SET WITH PROJECTION OF NORTH CAROLINA STATE PLANE COORDINATE SYSTEM FI PS 3200
(NAD83).
„c.
4DUKE
' EN RGY
PROGRESS
d.
z
d.
A
GRAPHIC SCALE
340 0 340 680
(IN FEET)
DRAWN BY: R. YU DATE: 02/04/2020
REVISED BY: R. YU DATE: 04/11/2020
CHECKED BY: C. EADY DATE: 04/11/2020
APPROVED BY: C. EADY DATE: 04/11/2020
PROJECT MANAGER: C. EADY
FIGURE 4b
SIMULATED MAXIMUM BORON CONCENTRATIONS IN ALL
NON -ASH LAYERS DOWNGRADIENT OF THE EAST ASH BASIN
AFTER APPROXIMATELY 9 YEARS OF ACTIVE GROUNDWATER
REMEDIATION
UPDATED GROUNDWATER FLOW AND TRANSPORT
MODELING REPORT
TECHNICAL MEMORANDUM
ROXBORO STEAM ELECTRIC PLANT
SEMORA, NORTH CAROLINA

Demonstration of 02L Compliance for the
Roxboro East Ash Basin by December 31, 2029 April 13, 2020
Roxboro Steam Electric Plant
TABLES

Demonstration of 02L Compliance for the
Roxboro East Ash Basin by December 31, 2029 April 13, 2020
Roxboro Steam Electric Plant
TABLE 1
EAST ASH BASIN/GSA/DFAHA AREA ACTIVE REMEDIATION
APPROACH WELL SUMMARY
Number of
Location
Formation
Total Depth
Extraction Wells
(feet bgs)
18
GSA/DFAHA
Transition zone and
180
Bedrock
17
NW EAB/
Bedrock
200
GSA/DFAHA
15
N EAB
Bedrock
260
9
NE EAB
Bedrock
500
Number of Clean
Total Depth
Water Infiltration
Location
Formation
(feet bgs)
Wells
Saprolite,
27
GSA/DFAHA
Transition zone,
180
Bedrock
Prepared by: RY Checked by: CDE
Notes:
GSA - Gypsum Storage Area
DFAHA - Dry Fly Ash Silos, Transport and Handling Area
GPM - Gallon per minute
BGS - Below ground surface
The 59 extraction wells have an average modeled flow rate of 1.7 gpm. The 18 extraction wells next to the Intake
Canal are pumped so that the water levels are at 400 ft elevation, which is approximately 10 ft below the water
level in the Intake Canal. The remaining 41 extraction wells are pumped so that the water levels are near the
bottom of the wells.
The 27 clean water infiltration wells have an average flow rate of 2.8 gpm and the heads of the infiltration wells are
maintained at 20 feet above the ground surface.

Appendix K revised on April 3, 2020
Table 1: Summary of Capital and Annual Costs for the Nine Additional Extraction Wells
Source Area 1 - EAB/Industrial Landfill/LCID
Alternative 2 - Groundwater Extraction with 2L at EAB Geographic Limitation by 12/31/2029
Roxboro Steam Electric Plant
Semora, North Carolina
Capital Costs
TASK #
TASK
UNIT
QUANTITY
RATE
COST
1.0
Design/Engineering/Site Preparation
Pre -Design Field Planning
LUMP SUM
1
$136,000
$136,000
Design Document/Work Plan
LUMP SUM
1
$298,000
$298,000
Permitting
LUMP SUM
1
$33,000
$33,000
$467,000
2.0
11VIonitoring Well Installation
Monitoring Well Installation
EACH
0
$0
$0
$0
3.0
Remediation Wells Installation
Extraction Well Installation
EACH
9
$141,556
$i 274,000
Well Development
EACH
9
$14,222
$128,000
Conveyance Piping and Electrical
LUMP SUM
1
$417,000
$417,000
$1,819,000
4.0
Project Management
Project Management (10 % Capital Cost)
LUMP SUM
1
$229,000
$229,000
229,000
Total Capital Cost
$2,515,000
Operations, Maintenance & Monitoring Costs
TASK #
TASK
UNIT
QUANTITY
RATE
COST
1.0
Operations and Maintenance
Remediation Wells Operations and Maintenance
LUMP SUM
1
$344,000
$344,000
344,000
2.0
Groundwater Sampling
Groundwater Sampling Event
EACH
0
$0
$3.0 0
0
!Wellaintenance
Annual Well Maintenance and Replacement
EACH
1
$91,000
$91,000
91,000
4.0
Reporting
Annual Reporting
EACH
1
$90,000
$90,002
Five -Year Review Report
EACH
0.2
$88,000
$18,000
108,000
5.0
1 Project Management
Project Management (10 % Annual Cost)
LUMP SUM
1
$54,000
$54,000
$54,000
Total Annual Cost
$597,000
Present Worth Analysis
Year(s)
Cost Type
Total Cost
Discount
Factor
Present Value
0
Capital Costs
$2,515,000
1.000
$2,515,000
1-9
Annual Costs
$597,000
6.108
$3,646,000
10-12
1 Post -Remedy Monitoring
$218,000
1.755
$383,000
13
lWell Abandonment Costs
$36,000
0.530
$19,000
Total Life Cycle Cost $6,563,000
Note:
1. Life cycle represents net present value of expenditures with capital costs incurred in Year 0, annual costs incurred thereafter, and well abandonment in the last year. Discount Rate of 5
assumed.
2. Costs presented herein represent a best estimate at this time. Actual costs may change based on a variety of factors during implementation.
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