Duke Energy Roxboro Pilot Test Work Plan FINAL

DUKE
ENERGY®
June 24, 2020
State of North Carolina Department of Environmental Quality
Division of Water Resources
Raleigh Regional Office
Attn: Mr. Eric Rice
3800 Barrett Drive
Raleigh, NC 27609
Subject: Roxboro Pilot Test Workplan
Dear Mr. Rice:
Environmental, Health & Safety
526 S. Church Street
Mail Code: EC13K
Charlotte, NC 28202
On December 31, 2019, Duke Energy submitted a Corrective Action Plan Update (CAP) to
address the Roxboro Steam Station East Ash Basin. The CAP update included a robust
groundwater remediation system with extraction and clean water injection wells and associated
treatment.
On February 10, 2020, Duke Energy received a letter from the North Carolina Department of
Environmental Quality (NCDEQ) approving the commencement of a pilot test for six facilities,
including Marshall Steam Station. The letter included a request for the submittal of a Pilot Test
Work Plan for review. Attached is the Pilot Test Work Plan for the Roxboro Steam Station
Corrective Action Plan Remediation System.
Per the NCDEQ's suggestion, Duke Energy plans to set up a follow-up meeting to address any
questions or comments. If you have any immediate questions, please contact Andrew Shull at
Andrew.Shul I(a)-duke-energy.com.
Respectfully Submitted,
Andrew W. Shull, P.E.
Environmental Services
Cc: Steve Lanter, NCDEQ Central Office
Eric Smith, NCDEQ Central Office
Scott Davies, Duke Energy
Kimberlee Witt, Duke Energy
John Toepfer, Duke Energy
Brian Wilson, ERM
Enclosure: Roxboro Groundwater Corrective Action Pilot Test Work Plan

DUKE Groundwater Corrective
ENERGY. Action Pilot Test Work Plan
Roxboro Steam Electric Plant
June 23, 2020
Project No.: 0550525
The business of sustainability E RM

Signature Page
June 23, 2020
Groundwater Corrective Action Pilot Test
Work Plan
Roxboro Steam Electric Plant
y4/
Denice Nelson, Ph.D., P.E. (MN)
Partner
Jennifer Bryd, P.E.
Technical Director/Engineer-of-Record
ERM NC, Inc.
4140 Parklake Avenue
Suite 110
Raleigh, NC 27612
Brian Wilson, P.G.
Principal Geologist/Program Manager
Wesley May, P.E. (WI)
Technical Director
www.erm.com Project No.: 0550525 Client: Duke Energy Progress, LLC June 23, 2020

GROUNDWATER CORRECTIVE ACTION PILOT TEST WORK PLAN
Roxboro Steam Electric Plant
CONTENTS
CONTENTS
1. INTRODUCTION................................................................................................................................1
1.1 Regulatory Framework..........................................................................................................................1
1.2 Work Plan Objectives...........................................................................................................................1
2. PROJECT DESCRIPTION.................................................................................................................
3
2.1 Conceptual Site Model..........................................................................................................................4
2.2 Corrective Action Plan..........................................................................................................................6
2.3 Selected Remedy Design Overview.....................................................................................................6
3. PILOT TEST DATA COLLECTION OBJECTIVES............................................................................8
4. PILOT TEST IMPLEMENTATION ACTIVITIES.................................................................................9
4.1 Pilot Test Basis of Design.....................................................................................................................9
4.1.1 Extraction Wells and Subsurface Infrastructure...................................................................9
4.1.2 Node Buildings...................................................................................................................11
4.1.3 Ancillary Systems...............................................................................................................12
4.2 Pilot Test Implementation...................................................................................................................12
4.2.1 Design Activities.................................................................................................................12
4.2.2 Permitting Activities............................................................................................................12
4.2.3 Installation Activities...........................................................................................................13
4.2.4 Construction Quality Assurance.........................................................................................15
4.2.5 Data Collection Activities...................................................................................................15
4.2.6 Scale -Up Activities.............................................................................................................16
4.3 Pilot Test Implementation Schedule...................................................................................................16
5. REFERENCES.................................................................................................................................17
List of Attached Tables
Table 1: Pilot Test Data Quality Objectives
Table 2: Basis of Design Summary
Table 3: Proposed Well Construction Details
Table 4: Effectiveness Monitoring Plan Summary
www.erm.com Project No.: 0550525 Client: Duke Energy Progress, LLC June 23, 2020 Page i

GROUNDWATER CORRECTIVE ACTION PILOT TEST WORK PLAN
Roxboro Steam Electric Plant
CONTENTS
List of Attached Figures
Figure 1: Source Area Overview Map
Figure 2: Full -Scale Design Layout
Figure 3: Pilot Scale Remedy and Monitoring Layout
Figure 4: Process Flow Diagram
Figure 5: Groundwater Extraction Well Schematic
Acronyms and Abbreviations
Name
Description
bgs
below ground surface
CAP
Corrective Action Plan
COI
constituent of interest
CSA
Comprehensive Site Assessment
CSM
Conceptual Site Model
DFAHA
Dry Fly Ash Handling Area
EAB
Eastern Ash Basin
EMP
Effectiveness Monitoring Plan
ft
feet
gpm
gallons per minute
G.S.
North Carolina General Statutes
GSA
Gypsum Storage Area
HASP
Health and Safety Plan
HDPE
high -density polyethylene
LCID
land -clearing and inert debris
LRB
Lined Retention Basin
NCAC
North Carolina Administrative Code
NCDEQ
North Carolina Department of Environmental Quality
NPDES
National Pollution Discharge Elimination System
O&M
operation and maintenance
OSHA
Occupational Safety and Health Administration
psi
pounds per square inch
V
volt
WAB
Western Ash Basin
www.erm.com Project No.: 0550525 Client: Duke Energy Progress, LLC June 23, 2020 Page ii

GROUNDWATER CORRECTIVE ACTION PILOT TEST WORK PLAN
Roxboro Steam Electric Plant
INTRODUCTION
INTRODUCTION
ERM NC, Inc. (ERM) prepared this Pilot Test Work Plan (Work Plan) on behalf of Duke Energy Progress,
LLC (Duke Energy) for the Roxboro Steam Electric Plant (the "site") in Person County, North Carolina
(Figure 1). This Work Plan provides the details of the proposed Source Area 1 groundwater extraction
pilot test for remediation of groundwater as described in the Corrective Action Plan (CAP) Update
prepared by SynTerra Corporation and dated December 31, 2019 (SynTerra 2019). Submission of this
Work Plan fulfills the North Carolina Department of Environmental Quality (NCDEQ) approved pilot test
approach included in their letter to Duke Energy dated February 10, 2020.
1.1 Regulatory Framework
Duke Energy has completed numerous environmental site assessments of site media associated with
combusted coal residuals (CCR), the detailed findings of which are presented in the CAP. These prior
site assessments, the CAP, and this Work Plan were prepared in accordance with the requirements of
Section 130A-309.21 1 (b) of the G.S., as amended by the 2014 North Carolina Coal Ash Management
Act, and consistent with the North Carolina Administrative Code (NCAC), Title 15A, Subchapter 02L
.0106 corrective action requirements and with the written guidance provided by NCDEQ.
At the request of NCDEQ, Duke Energy developed a constituents of interest (COI) management process
to support the understanding of COI behavior and distribution in groundwater and to aid in the selection of
the remedial approach. This COI management process is supported by multiple lines of technical
evidence and provides the basis for the selected remedial approach. The data and results of the process
are documented in detail in the CAP.
While no unacceptable environmental risk was identified, the focus of the CAP and this Work Plan is
conformance of groundwater with the requirements of G.S. Section 130A-309.211. The remedial actions
described herein pertain to the applicable North Carolina groundwater standards (NCAC, Title 15A,
Subchapter 02L, Groundwater Classification and Standards 02L; Interim Maximum Allowable
Concentrations; or background values, whichever is greater) at or beyond the Geographic Limitations
defined in the CAP. COI were detected above the applicable standards at or beyond the Geographic
Limitations of 2 ash basin source areas (East Ash Basin [EAB], and Gypsum Storage Area [GSA]/Dry Fly
Ash Handling Area [DFAHA]) at the site.
The CCR impoundments EAB and West Area Basin (WAB) are classified as low -risk (pursuant to N.0
General Statue Section 130A-309.213[d][1]) as documented by NCDEQ in a letter dated November 14,
2018. These areas are subject to the applicable closure standards (G.S. Section 130A-309A.214[a][3]),
which requires closure as soon as practicable, but no later than December 31, 2029. The selected
remedy is driven by this 02L groundwater standards compliance timeline.
In a NCDEQ determination letter dated April 1, 2019, the CCR surface impoundments must be closed.
Closure activities are documented separately.
1.2 Work Plan Objectives
The primary objectives of this Work Plan are to provide a general description of the project and the
proposed pilot test area, a summary of the data objectives for the pilot test, and a discussion of the
proposed pilot test design and implementation details. Data collected from the pilot test will be used to
inform the full-scale remedy. Parameters such as well capacity, area of hydraulic influence, and
concentration reductions will be evaluated during pilot test implementation. Design modifications will be
applied to the full-scale Corrective Action Design Work Plan as necessary to optimize system
performance based on pilot test data. The pilot test objectives are:
www.erm.com Project No.: 0550525 Client: Duke Energy Progress, LLC June 23, 2020 Page 1

GROUNDWATER CORRECTIVE ACTION PILOT TEST WORK PLAN INTRODUCTION
Roxboro Steam Electric Plant
■ Accelerate the corrective action process to meet the Consent Order obligation of meeting applicable
groundwater standards by December 31, 2029 at or beyond the Geographic Limitation,
■ Optimize full-scale system performance by using adaptive design methods based on data collected
during pilot test, and
■ Focus the pilot test on the most challenging areas at the Cliffside site and thereby make near -term
progress towards achieving the applicable standards
Additional details of pilot test objectives are presented in Section 3.
www.erm.com Project No.: 0550525 Client: Duke Energy Progress, LLC June 23, 2020 Page 2

GROUNDWATER CORRECTIVE ACTION PILOT TEST WORK PLAN
Roxboro Steam Electric Plant
PROJECT DESCRIPTION
2. PROJECT DESCRIPTION
The purpose of this pilot test is to inform the design of the full-scale remedial system at the site. The
following section provides a brief description of the site and a summary of work completed to date and
presented in full in the CAP.
Site Background
The CAP identifies three source areas at the site. These areas, as well as the respective Geographic
Limitations, are shown on Figure 1 and are described in further detail below.
■ Source Area 1: The East Ash Basin (EAB) and unlined areas of the industrial landfill (halo area),
which happens to include the land -clearing and inert debris (LCID) landfill. Proposed pilot test
activities will be conducted in this area.
■ Source Area 2: This source area consists of the West Ash Basin (WAB). Monitoring only as
groundwater currently does not exceed applicable 02L groundwater quality standards; therefore,
groundwater corrective action is not required at this time (under 15A NCAC 02L.0106).
■ Source Area 3: The Gypsum Storage Area (GSA) and Dry Fly Ash Handling Area (DFAHA).
The constituents of interest (COls) in groundwater at the site are boron, selenium, strontium, sulfate, and
total dissolved solids. A summary of the source area remedial goals and selected remedies is presented
below.
Source Area
Remedial Goal
Selected Remedy
Area 1
Reduce COI concentrations to below
applicable North Carolina Standards at or
Groundwater extraction
beyond Geographic Limitation.
Monitoring only as groundwater currently
Maintain groundwater quality at or below
does not exceed applicable 02L
Area 2
applicable North Carolina Standards at or
groundwater quality standards; therefore,
beyond Geographic Limitation.
groundwater corrective action is not
required at this time (under 15A NCAC
02L.0106).
Area 3
Reduce COI concentrations to below
Groundwater extraction with clean water
applicable North Carolina Standards at or
infiltration
beyond Geographic Limitation.
The following sections provide additional source area groundwater remedy details for the areas where
groundwater corrective action is required (Source Areas 1 and 3).
Source Area 1
Source Area 1 consists of the EAB and halo area and is generally located east and north of Dunnaway
Road, west of McGhees Mill Road, and is bounded to the north by the Unit 3 cooling tower pond and the
Unit 3 hot water pond.
www.erm.com Project No.: 0550525 Client: Duke Energy Progress, LLC June 23, 2020 Page 3

GROUNDWATER CORRECTIVE ACTION PILOT TEST WORK PLAN
Roxboro Steam Electric Plant
PROJECT DESCRIPTION
Remediation design in the CAP estimated the following extraction well networks in order to meet
regulatory groundwater requirements. The extraction wells identified below are included for installation in
this Work Plan. The Remediation Areas are shown on Figure 3.
■ Remediation Area C: 12 extraction wells north of the EAB Geographic Limitation adjacent to the
DFAHA;
■ Remediation Area B: 5 extraction wells in the area of the unnamed pond north of the EAB
Geographic Limitation;
■ Remediation Area A: 15 extraction wells on the northeast side of the EAB Geographic Limitation; and
■ 9 extraction wells northeast of the halo area.
This pilot test phase will include the installation of 41 groundwater extraction wells, 32 wells as specified
in the CAP, and nine additional wells located near the halo area. Locations of the proposed wells are
shown on Figure 2. The selected pilot test area is discussed in more detail in Section 2.4.
Source Area 3
Source Area 3 (the GSA and the DFAHA) is north and downgradient of the EAB.
Remediation design in the CAP estimated the following extraction and injection wells in order to meet
regulatory groundwater requirements. The extraction and injection wells identified below will not be
included for installation in this Work Plan.
■ 18 extraction wells downgradient of the GSA and DFAHA.
■ 27 infiltration wells downgradient of the GSA and DFAHA.
Installation of these extraction wells and clean water infiltration wells will be a part of the full-scale design
and will not be completed as a part of this pilot test. The location of these wells are shown on Figure 2.
Full-scale design will be informed by the results of the pilot testing activities performed in Source Area 1.
2.1 Conceptual Site Model
A robust Conceptual Site Model (CSM) was developed for the site that was detailed and presented
graphically in the referenced CAP (SynTerra 2019). The key elements of the CSM are summarized below.
The site is located in the Piedmont Physiographic Province, which conforms with the general
hydrogeologic framework for the Blue Ridge/Piedmont area, characterized by perennial flow in a slope -
aquifer system within a local drainage basin with a perennial stream (LeGrand 2004). The groundwater
system associated with the EAB and WAB is divided into the following three distinct hydrostratigraphic
zones to distinguish the interconnected groundwater system:
Shallow (surficial) flow zone is characterized by residual silty sands or clayey soils, fill and reworked
soils, alluvium, regolith, and saprolite.
■ Deep (transition) flow zone consists of a relatively transmissive zone of partially weathered rock
encountered below the shallow zone. The transition zone is generally continuous throughout the site
and ranges under saturated and unsaturated conditions in thicknesses from less than 1 to 45 feet (ft).
■ Bedrock flow zone is characterized as lithified slightly weathered to unweathered solid rock fractured
to varying degrees. Bedrock in the area includes volcanic and sedimentary rocks that have been
metamorphosed, intruded by coarse -grained granitic rocks, and subjected to regional structural
deformation. The dominant rock type consists of biotite gneiss, felsic gneiss, or granitic gneiss.
www.erm.com Project No.: 0550525 Client: Duke Energy Progress, LLC June 23, 2020 Page 4

GROUNDWATER CORRECTIVE ACTION PILOT TEST WORK PLAN PROJECT DESCRIPTION
Roxboro Steam Electric Plant
The groundwater system in the natural materials (shallow/transition/bedrock flow zones) is consistent with
the regolith-fractured rock system and is characterized as an unconfined, interconnected groundwater
flow system indicative of the Piedmont Physiographic Province. A conceptual model of groundwater flow
in the Piedmont, which is applicable to Roxboro, was developed by LeGrand (1988, 1989) and Harned
and Daniel (1992). In accordance with the model, groundwater is recharged by drainage and rainfall
infiltration in the upland areas followed by discharge to the perennial stream. Flow in the unconfined
regolith (shallow and deep aquifer zones) follows porous media principals, while flow in bedrock occurs in
joints and fractures. The groundwater flow direction for the transition/bedrock flow zone associated with
each ash basin is generally from south to north-northwest toward the NPDES-permitted wastewater
ponds. Groundwater flow associated with the GSA and DFAHA is north toward the Intake Canal. Based
on the orientations of lineaments and open bedrock fractures at Roxboro, horizontal groundwater flow
within the bedrock primarily occurs approximately parallel to the hydraulic gradient, with no preferential
flow direction.
Calculated horizontal groundwater flow velocities for the transition zone are approximately 35.8 and
35.2 ft per year in the vicinity of the EAB and WAB, respectively using the April 2019 groundwater
elevation data. Calculated horizontal flow velocities for the bedrock zone are approximately 42.9 and
42.2 ft per year for the EAB and WAB, respectively. Horizontal distribution of COls in groundwater
proximate to the ash basins is limited spatially to the north. The physical extent of constituent migration is
controlled by hydrologic divides to the west, south, and east of the ash basins; dilution from unaffected
groundwater; and the discharge of groundwater to surface water. The groundwater discharges to
NPDES-permitted wastewater ponds. Geochemical processes stabilize and limit certain constituent
migration along the flow path. COls in groundwater are contained within Duke Energy's property. COI
distribution extends from the ash basins toward NPDES-permitted wastewater ponds and, in the case of
the EAB, toward downgradient additional source areas. The plumes associated with the ash basins have
been characterized and are stable. It is expected that information obtained during the implementation of
the pilot test may be used to revise the CSM in the future if deemed appropriate.
A brief summary of the key conclusions of the CSM include:
■ No indication of completed exposure pathways that would contribute to an increase in risk to
human health;
■ No indication of increased risk to ecological receptors;
■ Cessation of sluicing and active decanting at WAB will reduce hydraulic head and reduce rate of
COI transport, proving source control prior to closure;
■ Ash basin and underlying groundwater system is primarily a horizontal flow system with limited
downward COI migration;
■ Horizontal COI distribution at or beyond the Geographic Limitations is spatially limited due to
presence of hydrologic divides, dilution, and groundwater -to -surface water discharge zones; and
■ Geochemical processes contributing to migration stability of COls is variable by COI and
geochemical conditions.
The corrective actions presented in the CAP and this Work Plan are based on the above findings.
Specifically, the selected corrective actions enhance the current conditions by lowering the groundwater
hydraulic head in selected areas. Additional information obtained during pilot test implementation will be
used to confirm and possibly further refine the CSM in the future as appropriate.
www.erm.com Project No.: 0550525 Client: Duke Energy Progress, LLC June 23, 2020 Page 5

GROUNDWATER CORRECTIVE ACTION PILOT TEST WORK PLAN
Roxboro Steam Electric Plant
PROJECT DESCRIPTION
2.2 Corrective Action Plan
At the request of NCDEQ, Duke Energy developed a specific process to gain an understanding of the
COI behavior and distribution in groundwater and to aid in identification of COls related to the ash basins
that may require corrective action. This constituent management process consists of three steps:
1. Perform a detailed review of the applicable regulatory requirements under NCAC, Title 15A,
Subchapter 02L.
2. Understand the potential mobility of site -related COls in groundwater based on site hydrogeology and
geochemical conditions.
3. Determine the COI distribution related to the ash basins and downgradient source areas under
current or predicted future conditions.
Multiple lines of evidence, including empirical data, geochemical modeling, and groundwater flow and
transport modeling, support this constituent management process. This approach has been used to
understand and predict COI behavior in the subsurface related to the ash basins and downgradient
sources, or constituents that are naturally occurring. COls in groundwater that have migrated beyond the
Geographic Limitation at concentrations greater than 2L Standards, Interim Maximum Allowable
Concentrations and background values that are related to the ash basins and downgradient source areas
are subject to corrective action. COls that are naturally occurring at concentrations greater than the 2L
Standard do not require corrective action.
The installation of a groundwater extraction system, including groundwater extraction with clean water
infiltration in combination, and/or compliance monitoring was determined to be the most effective remedial
strategy for the three source areas. This strategy was compared against alternatives such as a low -
permeability barrier, a permeable reactive barrier, and encapsulation. The CAP evaluated the pros and
cons of these different methods. Groundwater extraction was selected as the method of choice due to the
site geology, properties of the COIs, and results of groundwater modeling studies.
The CAP outlines the corrective actions for groundwater remediation COls associated with the three
source areas at the site. The CAP outlines a multi -component solution that includes implementation of:
■ Source control (i.e., ash basin decanting and/or closure);
■ Groundwater remediation;
■ An Effectiveness Monitoring Plan (EMP); and
■ A Confirmatory Monitoring Plan.
While the CAP evaluates multiple remedial actions related to source control, groundwater remediation,
and monitoring, this Work Plan pertains specifically to groundwater remediation at the site.
2.3 Selected Remedy Design Overview
The pilot test extraction well network is positioned near the Geographic Limitation of Source Area 1 based
on the results of the model simulations conducted as part of the CAP. The pilot test well placement
provides COI mass removal and prevents migration of groundwater containing COls beyond the
Geographic Limitation. The extraction of groundwater from the targeted zones has been predicted to yield
sufficient control for COls at the site. Control will be achieved by the creation of a capture zone by
manipulation of the hydraulic gradient through pumping wells.
The pilot test will consist of a network of 41 vertical extraction wells. Buried piping will convey extracted
groundwater from the extraction well network to several collection points or "nodes." Each node building
www.erm.com Project No.: 0550525 Client: Duke Energy Progress, LLC June 23, 2020 Page 6

GROUNDWATER CORRECTIVE ACTION PILOT TEST WORK PLAN PROJECT DESCRIPTION
Roxboro Steam Electric Plant
will provide a location for power, controls, communication, and subsequent water transfer. Discharge from
each node building will converge to a single header pipe and discharge to existing facility wastewater
infrastructure, ultimately discharging to the existing Lined Retention Basin (LRB). Figures 2 and 3
present the layout of the pilot test extraction wells and conveyance systems.
Extraction well arrangement and spacing has been determined by the groundwater modeling/simulations
presented in the CAP. Overall, the optimized well network spacing is approximately 45 to 75 ft between
wells. The total depths of the extraction wells range from 200 to 560 ft below the ground surface (bgs),
and will primarily consist of open boreholes.
The total anticipated groundwater extraction rate from the pilot test extraction wells is approximately
50 gallons per minute (gpm). The anticipated individual well groundwater extraction rates range from
approximately 0.1 to 6.2 gpm. Each extraction well will be equipped with flow metering instrumentation.
Pumps will be controlled individually based on water level instrumentation. Figure 5 presents the
extraction well schematic.
The full-scale system design is expected to include an additional 18 vertical extraction wells to target the
transition/bedrock flow zone and 27 vertical infiltration wells to target the shallow/transition/bedrock zone.
www.erm.com Project No.: 0550525 Client: Duke Energy Progress, LLC June 23, 2020 Page 7

GROUNDWATER CORRECTIVE ACTION PILOT TEST WORK PLAN PILOT TEST DATA COLLECTION OBJECTIVES
Roxboro Steam Electric Plant
3. PILOT TEST DATA COLLECTION OBJECTIVES
Data collected during the pilot test will be used to support the following objectives:
■ Accelerate the corrective action process to meet the Consent Order obligation of meeting
applicable groundwater standards by December 31, 2029 at or beyond the Geographic Limitation.
■ Optimize full-scale system performance by using adaptive design methods based on data
collected during pilot test
■ Focus the pilot test on the most challenging areas at the Roxboro site and thereby make near -
term progress towards achieving the above -referenced standards
Data collected during the pilot test will be used to optimize the pilot test system operations, evaluate the
effectiveness of the pilot test system in reducing COI concentrations beyond the Geographic Limitation,
and to inform the full-scale system design. Pilot test data objectives have been defined and are presented
in Table 1. The data objectives include evaluation of well capacities, the area of hydraulic influence, the
hydraulic connectivity and reductions in groundwater COI concentration. Hydrogeologic testing of
extraction wells will assess well performance, and will also advance the understanding of site hydraulic
influence as part of ongoing groundwater remediation activities. Hydrogeologic testing is discussed in
more detail in Section 4.2.5.1.
Operational data will be collected from the system during the pilot test to assess performance. Extraction
well flowrates, groundwater elevations, and other operational parameters will be collected to provide
feedback for system optimization and performance. Collection of operational data is discussed in more
detail in Section 4.2.5.2.
In addition to the hydrogeologic testing and collection of operational data, Duke Energy has prepared an
EMP as discussed and presented in Appendix O of the CAP. The EMP includes an optimized
groundwater monitoring network for the EAB, GSA, and DFAHA source areas based on site -specific COI
mobility and distribution. The EMP is designed to be adaptable and targets key areas where changes to
groundwater conditions are most likely to occur during corrective action implementation and basin closure
activities. The EMP includes provisions for a post -closure monitoring program in accordance with G.S.
Section 130A-309.214(a)(4)k.2 upon completion of EAB closure activities. A summary of the EMP is
presented in Table 4.
The results of the pilot test will be used to evaluate the effectiveness of the selected remedy and
potentially provide refinement of the CSM and groundwater model. The results may also determine the
hydrogeologic design parameters for expansion and/or optimization of the extraction well network during
subsequent phases of the remedy. A more detailed site -specific pilot test monitoring plan will be
submitted to the NCDEQ prior to pilot test implementation. This monitoring plan will include details
regarding such items as sampling frequency, parameter list, and well locations that will be used to
determine the effectiveness of the pilot test program.
www.erm.com Project No.: 0550525 Client: Duke Energy Progress, LLC June 23, 2020 Page 8

GROUNDWATER CORRECTIVE ACTION PILOT TEST WORK PLAN PILOT TEST IMPLEMENTATION ACTIVITIES
Roxboro Steam Electric Plant
4. PILOT TEST IMPLEMENTATION ACTIVITIES
The following sections provide general design details of the pilot test activities and associated tasks
required for its implementation.
4.1 Pilot Test Basis of Design
This section provides an overview of the pilot test groundwater extraction system and equipment
specification. The basis of design elements for the pilot test system are summarized in Table 2.
4.1.1 Extraction Wells and Subsurface Infrastructure
The pilot test system will consist of 41 vertical extraction wells, EX-19 through EX-59, installed across
three separate well areas (Areas A through C) in the vicinity of the EAB and DFAHA. This layout is shown
on Figures 2 and 3. Each well area will contain the specified number of extraction wells, conveyance
piping, electrical and control conduit, and a control building (i.e., "node" building). The three separate
areas will be interlinked through a communication system and will operate as a single system. All
extracted groundwater will be conveyed to the existing sump located within the DFAHA for conveyance to
the existing LRB. A process flow diagram is presented as Figure 4.
The planned extraction well zones are divided as follows:
■ Area A: Consists of 24 bedrock extraction wells, EX-24 through EX-38 and EX-51 through EX-59,
located northeast of the EAB. Wells installed to depths ranging from approximately 240 to 520 ft bgs
and estimated extraction rates ranging from 0.1 to 6.2 gpm (approximately 35 gpm combined flow);
Area B: Consists of five bedrock extraction wells, EX-19 through EX-23, located around the
unnamed pond north of the EAB. Wells installed to an approximate depth of 180 ft bgs and estimated
extraction rates from 0.5 to 0.6 gpm (approximately 3 gpm combined flow); and
Area C: Consists of 12 bedrock extraction wells, EX-39 through EX-50, located north of the EAB near
the DFAHA. Wells installed to an approximate depth of 180 ft bgs and estimated extraction rates from
0.1 to 2.4 gpm (approximately 12 gpm combined).
4.1.1.1 Extraction Wells
The 41 extraction wells will be advanced to the approximate depths specified above and on Table 3.
Extraction well boreholes will be a minimum of 12 inches in diameter and may be installed using air -rotary
and/or rotosonic drilling methods. The extraction wells will be constructed of a minimum 12-inch diameter
steel casing through the unconsolidated material and an open borehole in bedrock below the casing. The
estimated depth of the casing is presented in Table 3. A 2-to-3-ft layer of hydrated bentonite chips will be
placed at the bottom of the annulus between the borehole and the casing to seal it prior to placing grout.
The remainder of the well annulus will be grouted with a cement-bentonite slurry. Following the required
minimum grout curing time, the well boring will be advanced to its terminal depth. Adjustments to casing
and total well depths may be made based on observed field conditions. All wells will be installed and
sealed in accordance with the NCAC, Title 15A, Subchapter 2C.100 Well Construction Standards and
with construction overseen by a North Carolina —licensed Professional Geologist.
At the time of installation, all wells will be temporarily completed with a 12-inch diameter monitoring well
vault. Well construction details for the groundwater extraction wells are shown on Figure 5.
www.erm.com Project No.: 0550525 Client: Duke Energy Progress, LLC June 23, 2020 Page 9

GROUNDWATER CORRECTIVE ACTION PILOT TEST WORK PLAN PILOT TEST IMPLEMENTATION ACTIVITIES
Roxboro Steam Electric Plant
4.1.1.2 Groundwater Extraction Pumps
Extraction pumps will be approximately 0.5 to 3 horsepower electric submersible well pumps (e.g.,
Grundfos Redi Flo). The pumps will be a 230-volt (V) single-phase or 480-V three-phase electric multi-
stage submersible type and will discharge through a 1- to 1.25-inch-diameter steel riser pipe.
Each pump will be installed with an in -well level controls (e.g., high and low level switches) in order to
control and protect the pump against run dry running conditions. Pump savers will also be installed to
protect the pump from dry well, over and under voltage, rapid cycling, and jammed pump conditions.
Upon system startup, extraction well performance will be evaluated to determine groundwater drawdown
shut-off points based on operating conditions to develop an operational strategy that achieves the desired
hydraulic capture. Upon refinement of the operational strategy, pumps will be operated continuously if
sufficient groundwater flow can be achieved or, if continuous flow cannot be maintained, intermittently
based on the well level switches.
4.1.1.3 Extraction Well Vaults
A concrete vault will be placed over the wellhead of each extraction for protection. The vault will be
equipped with an H-20-rated steel or aluminum access hatch. The size of the well vault will be determined
during completion of the pilot test detailed design. The bottom of the vault will be concrete to provide
containment if a leak were to occur within the vault. A float switch will be placed into each well vault to
shutdown the extraction pump and alert the operators if water is present in the vault above the set point of
the level switch.
The vault will contain the transition from the riser piping to the below -grade conveyance piping. An
isolation valve and pressure gauge will be installed within the vault. In addition to the piping, electrical
junction boxes will be installed in each vault for termination of the power lead from the pump and control
wiring from the down -well level switches. Penetrations through the wall or base of the vault will be sealed.
4.1.1.4 Conveyance Piping
Each extraction well will have a dedicated conveyance pipe running from the wellhead to the designated
node building. This will allow for metering (both mechanical and digital) and well performance monitoring
in a central location and will minimize disturbance to each facility's operations during operation and
maintenance (OW) visits. Extraction well conveyance piping will be a minimum of 2-inch nominal
diameter high -density polyethylene (HDPE) to allow for cleaning, if necessary.
Flow from each node building will be combined into a common header that will originate at Node Building
A and terminate at the discharge location (DFAHA sump). The header pipe will be constructed of HDPE
and will include isolation valves and other appurtenances where appropriate. Pipe -sizing will be
determined during detailed pilot test system design and will include an allowance for future expansion
capacity.
The conveyance and header piping will be installed within a common trench at a minimum depth of
30 inches. The trench will be backfilled with the soil excavated from the trench. If the excavated soil is
determined to be unsuitable for use as backfill, soil from other on -site location or imported fill will be used
as backfill. Backfill material will be compacted during placement.
The design will include a number of spare conveyance pipes to support potential future expansion
requirements and repair in the case of pipe failure/fouling. The spare conveyance pipes will be
strategically located and stubbed up at the ground surface as determined during the design.
www.erm.com Project No.: 0550525 Client: Duke Energy Progress, LLC June 23, 2020 Page 10

GROUNDWATER CORRECTIVE ACTION PILOT TEST WORK PLAN PILOT TEST IMPLEMENTATION ACTIVITIES
Roxboro Steam Electric Plant
4.1.1.5 Electrical and Control Conduit
Conduit will be installed from the control building to each extraction well vault. The conduit will carry the
electrical conductors to power the submersible pumps as well as the control wiring for the controls located
in the vault and within the well. Buried conduit will be constructed of either polyvinyl chloride or HDPE.
Handholds will be placed as necessary to facilitate installation of the power and control wiring.
The conduit will be installed in a common trench with the conveyance and header piping. The trench will
be backfilled with the soil excavated from the trench. If the excavated soil is determined to be unsuitable
for use as backfill, soil from other on -site location or imported fill will be used as backfill. Backfill material
will be compacted during placement.
4.1.2 Node Buildings
Node Buildings A and B will consist of a manifold, flow meters, valves and gauges, sampling ports, a 500-
to-1,000 gallon HDPE equalization/holding tank, transfer pump(s), and a system controls cabinet with a
PLC/HMI. All extracted groundwater will be pumped through a manifold where it will be combined and
then directed to the holding tank located at each node building. Level switches in the holding tank will
control a transfer pump, which will pump the accumulated groundwater for conveyance to the DFAHA
sump via the header piping shown on Figures 2 and 3. A high -high level switch will be installed in each
holding tank to shut down the extraction wells in the event the transfer pump fails.
Node Building C will include similar instrumentation and controls to the other compounds. However, it will
not contain a holding tank and transfer pump. Due to its close proximity to the dry fly ash sump, extraction
well flows will instead be combined via a well manifold and conveyed directly to the final discharge
location in a common header.
4.1.2.1 Groundwater Manifold
Each leg of the groundwater manifold will convey flow from individual wells before combining. The legs
will be fitted with various components such as a pressure indicator, sample port valve, manual flow
control/isolation valve, flow meter, and check valve. Sample port valves will be placed in the manifold legs
to allow for water sample collection for observation and sampling. Flow control and isolation valves will be
utilized for preventing backflow, allowing manual throttling of flow, and isolation during service intervals.
The instantaneous flow rate and total volume of extracted groundwater for each extraction well will be
measured using a flow meter contained within each node building. The flow meters will transmit flow rate
and flow total to the PLC/HMI where it will be continuously logged, stored, and reported daily/weekly to
the system operator(s). The mechanical flow totalizers will provide redundant data in the event of data
loss or flow meter failure.
4.1.2.2 Holding Tank and Transfer Pump
All node buildings will discharge to a common collection header or holding tank prior to discharge to the
DFAHA sump discharge location. The discharge location is shown on Figure 2. The size of the header
pipe or capacity of the holding tank will be determined in the design. The instantaneous flow rate and total
flow will be measured with a paddle wheel or similar flow meter. The total flow rate will also be measured
using a mechanical flow totalizer. The mechanical flow totalizer will provide redundant data in the event of
data loss or flow meter failure. The discharge from the groundwater extraction system will be interlocked
with any controls for the DFAHA sump pump as needed for safe operation.
www.erm.com Project No.: 0550525 Client: Duke Energy Progress, LLC June 23, 2020 Page 11

GROUNDWATER CORRECTIVE ACTION PILOT TEST WORK PLAN PILOT TEST IMPLEMENTATION ACTIVITIES
Roxboro Steam Electric Plant
4.1.3 Ancillary Systems
4.1.3.1 Electrical Service and Distribution
Main supply will be a 480/277 VAC, three-phase, 400 ampere service. All extraction pumps, transfer
pumps, PLCs, and other equipment will be operated on a single- or three-phase 120/240/480-V service at
60 hertz. Where possible, connections will be made to existing facility electrical distribution and will be
regulated down from a higher voltage, 3-phase service using a transformer where necessary. If
connection to existing facility distribution is not possible, a new power drop will be installed. Each node
building will include one or more 120-V power outlets and industrial -style ceiling lights.
4.1.3.2 Communications
Each pump controller will be connected to the central PLC/HMI, which will provide data logging functions.
Individual extraction well flow rates and total flows will be accessible via remote telemetry and supervisory
control and data acquisition system, minimizing the need for regular O&M visits.
The main control panel will include a PLC/HMI used to control all system operations. The PLCs from each
node building will have remote communication capabilities to facilitate intercommunication, alarms and
interlock callouts, and site -wide operational control. The system operator will be able to access the
system and data remotely through a personal computer, tablet, or smartphone interface that has the
same view, functionality, and levels of permissions as the on -site HMI touchscreen display.
4.2 Pilot Test Implementation
The following sections provide brief descriptions of the activities anticipated to implement the pilot test
phase.
4.2.1 Design Activities
Section 4.1 and associated figures represent an overview of the pilot test design. Prior to implementation
of the pilot test, additional design activities will be completed to provide construction level details including
drawings, specifications, and contracting documents. The following provides a general list of the
anticipated additional design activities:
■ Evaluation of total dynamic head within extraction well conveyance pipe, node building piping and
header piping to select system components (pumps, pipe materials and diameters, etc.);
■ Development of a piping and instrumentation diagram detailing extraction well network
instrumentation and controls;
■ Establishment of a long-term O&M program, controls, and monitoring strategy for the groundwater
extraction system;
■ Drafting of plan view and cross -sectional construction drawings detailing site -wide grading, trenching,
and associated remedial activities; and
■ Finalization of the contractor bid package outlining project scope and contractor requirements and
conditions for implementation.
4.2.2 Permitting Activities
Duke Energy will obtain permits or equivalencies for applicable permits prior to initiating work related to
the pilot test. As part of well installation planning activities and final design/contracting, Duke Energy
www.erm.com Project No.: 0550525 Client: Duke Energy Progress, LLC June 23, 2020 Page 12

GROUNDWATER CORRECTIVE ACTION PILOT TEST WORK PLAN PILOT TEST IMPLEMENTATION ACTIVITIES
Roxboro Steam Electric Plant
anticipates evaluating need and potentially preparing plans for or obtaining the following permits (or
equivalents):
■ Extraction/Recovery Well Permit
■ Erosion and Sediment Control (E&SC) Plan
■ NCDEQ Construction Stormwater General Permit / e-NOI
■ NPDES Modification
■ Local and County Permits
A preliminary review of required permitting under 15A NCAC 02C .0105 (4), extraction well permits for the
recovery of impacted groundwater are anticipated to be required. A detailed permit requirement review
will be completed during the final design and contracting activities. The schedule for each permit will be
determined during final design and will be determined by the implementation schedule.
4.2.3 Installation Activities
The following sections provide brief descriptions of the anticipated activities required to implement the
pilot test. An adaptive strategy will be used to ensure flexibility in design and implementation schedule. To
that end, the following sections should be considered as anticipated actions and pending final design,
and, thus, are subject to improvement.
4.2.3.1 Extraction Well Installation and Development
Prior to mobilization for any subsurface disturbance activity (i.e., drilling, trenching, or substantial
grading), a thorough evaluation of underground utilities in the vicinity of the proposed activities will be
completed. Proposed well construction details are provided in Table 3. Wells will be installed by a North
Carolina licensed driller and in accordance with applicable regulations. Detailed geologic and construction
logs will be prepared in the field during installation by an experienced field scientist or geologist.
No sooner than 48 hours following installation, the well will be developed using surging, jetting, and/or
pumping techniques and shall include removal of formation materials, drilling fluids and additives.
Development progress will continue until the water contains a target of no more than: (1) 5 milliliters per
liter of settleable solids; and (2) 10 Nephelometric turbidity units of turbidity as suspended solids.
Additionally, during development, pH, specific conductivity, temperature and turbidity should be monitored
frequently to establish natural conditions and evaluate whether the well has been completely developed
based on parameter stabilization. Following installation, the new well will be surveyed by a North Carolina
state -licensed surveyor as described in Section 4.2.3.5.
4.2.3.2 Waste Management Plan
Wastes generated during the remedy implementation will include concrete, asphalt, soils, drill cuttings,
groundwater, and purge water. Wastes will be managed on -site or recycled off -site. If a waste cannot be
managed on -site or recycled, the waste will be profiled according to the requirements of the approved
disposal facility prior to transportation off -site.
Excavation and drilling derived solid waste, which may consist of soil, concrete and asphalt, will be
managed by the facility consistent with ongoing applicable waste management practices. Wastes deemed
not appropriate for on -site management will be stored on -site in stockpiles, 55-gallon drums, or other
Department of Transportation —regulated containers and disposed at an appropriately licensed off -site
disposal facility at the direction of Duke Energy and in accordance with local, state, and federal
regulations.
www.erm.com Project No.: 0550525 Client: Duke Energy Progress, LLC June 23, 2020 Page 13

GROUNDWATER CORRECTIVE ACTION PILOT TEST WORK PLAN PILOT TEST IMPLEMENTATION ACTIVITIES
Roxboro Steam Electric Plant
Personal protective equipment, drilling expendables (e.g., packaging, sand/cement bags, and general
refuse), plastic, and related consumable material will be disposed as municipal waste.
Liquid waste, which will consist of decontamination fluids and well development water, will be managed at
through the on -site LRB. Wastes deemed not appropriate for on -site management will be stored on -site in
properly labelled drums or other Department of Transporation—regulated containers and disposed off -site.
4.2.3.3 Surveying
A North Carolina —licensed surveyor will survey the locations and elevations of the new extraction wells.
The locations and elevations will be referenced to the horizontal and vertical benchmarks established for
the site (i.e. State Plane Coordinates). The survey results will be accurate to ±0.01 ft vertically and ±0.1 ft
horizontally using vertical control datum NAVD 88.
Locations of the vaults, trenches, node buildings, spare pipe/conduit end points, and other key buried
infrastructure will be measured in the field to develop "as -built" drawings of the pilot scale system. Survey
data will be generated for these locations if deemed necessary and feasible. An "as -built' set of drawings
will be developed based on the measurements taken in the field during construction.
4.2.3.4 Extraction and Node Building Installation
Node building construction details will be determined during final design of the pilot test system. Modular
elements of the system that can be fabricated off -site will be utilized to the extent practical. This may
include the use of 8 ft wide by 40 ft long intermodal shipping containers (e.g., seabox). Node buildings will
house process equipment and provide a secure and climate -controlled environment. Node building
equipment (i.e., control panels, piping headers, tank connections, etc.) can be fabricated off -site, installed
within a pre -fabricated enclosure, and delivered to the site in a semi -complete condition and the final
assembling can be completed on -site.
Buried infrastructure includes all conveyance pipe (including spares), well electrical and instrumentation
conduit, extraction well vaults, clean -out vaults, electrical handholds other non -specified access vaults,
and the discharge tie-in location. Details of the trenching will be prepared during final design of the pilot
test system.
Site preparation such as grading or foundation construction may be required prior to placement of the
node buildings to provide adequate structural support.
.A generalized construction sequence follows:
■ Marking of utilities;
■ E&SC measures installation;
■ Site clearing and grubbing;
■ Well installation and development;
■ Trenching/buried infrastructure installation;
■ Node building site preparation;
■ Node building placement;
■ Field pipe and conduit connections to node building;
■ Wire installation;
■ Down well equipment installation;
www.erm.com Project No.: 0550525 Client: Duke Energy Progress, LLC June 23, 2020 Page 14

GROUNDWATER CORRECTIVE ACTION PILOT TEST WORK PLAN PILOT TEST IMPLEMENTATION ACTIVITIES
Roxboro Steam Electric Plant
■ Electric service installation;
■ Quality control testing; and
■ Shakedown and system startup.
All work will be performed in strict compliance with all applicable local and county codes. In addition, all
work will be performed in accordance with the latest editions of U.S. National Electrical Code of the
National Fire Protection Association, the National Electrical Safety Code, the American Institute of Steel
Construction, OSHA, and Electrical Licensing Board.
4.2.4 Construction Quality Assurance
4.2.4.1 Inspection and Testing of Conveyance Piping
Quality assurance testing of installed piping will involve visual inspection for construction defects and
quantitative hydrostatic pressure testing following standardized practices (e.g., ASTM E1003) and Duke
Energy requirements. Any failed inspections or tests will result in repair and retesting.
4.2.4.2 Startup Testing
Startup testing and troubleshooting will occur following completion of construction activities and is
estimated to last approximately 2 to 4 weeks. Startup testing will consist of operational testing of all
installed equipment and controls to confirm operation within the design parameters. Additionally, all alarm
and telemetry systems will be functionally tested to verify that data is properly recorded and
communicated. Sampling will conducted to establish baseline COI concentrations for the system. Startup
testing results will be documented in a construction completion report.
4.2.5 Data Collection Activities
4.2.5.1 Hydraulic Testing Data Collection
A subset of the extraction wells will be hydraulically stress -tested to assess individual well performance
respective of expected pumping rate. Hydraulic testing will advance the data quality objectives discussed
in Table 1 such as well capacity and area of hydraulic influence. The hydraulic testing Standard
Operating Procedure is briefly summarized as follows:
■ Install a pump and transducer within a pilot test extraction well for hydraulic testing, plus transducers
in nearby extraction and/or observation wells where feasible for monitoring during hydraulic testing.
■ Conduct a step-down and recovery test (up to 8 hours).
■ Conduct a long-term (up to 48 hours), constant -rate pumping test.
The resulting data will be analyzed to inform decision -making for both individual well and overall system
operations.
4.2.5.2 System Performance Data Collection
Following system startup, operational data will be logged on a set interval. The data will support the
criteria of Table 1. System data collection will likely consist of:
■ Instantaneous extraction flow rate for each well;
■ Total flow extracted from each well;
www.erm.com Project No.: 0550525 Client: Duke Energy Progress, LLC June 23, 2020 Page 15

GROUNDWATER CORRECTIVE ACTION PILOT TEST WORK PLAN PILOT TEST IMPLEMENTATION ACTIVITIES
Roxboro Steam Electric Plant
■ Operational run-time; and
■ Groundwater elevation (i.e., draw -down) at selected extraction wells.
This data will be accessible through direct -read instrumentation, PLC data logging files, and remote
telemetry. The data will be used to evaluate the operational performance of the system against the design
parameters.
4.2.5.3 Effectiveness Monitoring Plan Data Collection
In addition to the hydraulic testing of the extraction wells, and system operational performance data
evaluation, the EMP, included in Table 4, will be followed to provide comprehensive data collection,
evaluation, and reporting on the overall effectiveness of the selected remedy. While the EMP's
applicability goes beyond the pilot test, it will provide key data to inform the requirements of the data
quality objectives included in Table 1. The EMP will be implemented 30 days after CAP approval and will
replace the Interim Monitoring Plan. The EMP program includes:
■ Semi-annual groundwater monitoring of the EMP Groundwater Monitoring Network and analysis of
selected field and laboratory parameters; and
■ Annual effectiveness evaluation and reporting.
4.2.6 Scale -Up Activities
Data collected as part of the hydraulic testing, system performance data collection, and EMP data
collection, will collectively inform decisions about scale -up of the of the groundwater remedy to full-scale,
as outlined on the Data Quality Objectives (Table 1).
4.3 Pilot Test Implementation Schedule
The following provides the anticipated estimated schedule to complete the key milestones of this Work
Plan.
■ Permit Applications (June - July 2020)
■ Contracting (October 2020)
■ Extraction well network Installation (October 2020)
■ Extraction well hydraulic testing (December 2020)
■ Construction (March 2021)
■ Pilot test system startup (March 2021)
■ EMP implementation (ongoing following start-up)
■ Scale -up activities (to -be -determined)
www.erm.com Project No.: 0550525 Client: Duke Energy Progress, LLC June 23, 2020 Page 16

GROUNDWATER CORRECTIVE ACTION PILOT TEST WORK PLAN
Roxboro Steam Electric Plant
REFERENCES
5. REFERENCES
Harned, D., and C. Daniel. 1992. The Transition Zone Between Bedrock and Regolith: Conduit for
Contamination. In Daniel, C.C., White, R., and Stone, P., eds., Groundwater in the Piedmont,
Proceedings of a Conference on Ground Water in the Piedmont of the Eastern United States,
Charlotte, N.C., Oct. 16-18, 1989. Clemson, SC: Clemson University (336-348).
LeGrand, H. 1988. Region 21, Piedmont and Blue Ridge. In: J. Black, J. Rosenshein, P. Seaber, ed.
Geological Society of America, 0-2, pp 201-207.
LeGrand, H. 1989. A conceptual model of ground water settings in the Piedmont region, in groundwater in
the Piedmont. In: Daniel C., White, R., Stone, P., ed. Ground Water in the Piedmont of the
Eastern United States. Clemson, SC: Clemson University, pp 317-327.
LeGrand, H. 2004. A master conceptual model for hydrogeological site characterization in the Piedmont
and Mountain Region of North Carolina: A guidance manual. North Carolina Department of
Environment and Natural Resources, Division of Water Quality, Groundwater Section Raleigh,
NC, 55.
SynTerra (SynTerra Corporation). 2019. Corrective Action Plan (CAP) Update. Prepared by SynTerra
Corporation in December 2019.
www.erm.com Project No.: 0550525 Client: Duke Energy Progress, LLC June 23, 2020 Page 17

TABLES
www.erm.com Project No.: 0550525 Client: Duke Energy Progress, LLC June 23, 2020

Table 1 - Pilot Test Data Quality Objectives
Pilot Test Work Plan
Roxboro Steam Electric Plant
Semora, North Carolina
Table
1 - Pilot Test Data Quality Objectives
Restore groundwater at or beyond the geographic limitation affected by the ash
State the Problem
impoundments to the applicable standards or as close to the standards as is
economically feasible in accordance with 15A NCAC 02L. 0106.
Decision Statements
Is the number of wells, well configuration, and system capacity sufficient to
achieve the design objective outlined in the problem statement?
Study Area Boundaries
Source Area 1 (EAB) and Source Area 3 (DFAHA and GSA)
Inputs to the Decision
Decision Rules*
Compare well capacity with design.
Well capacity: calculated via flowmeters
If well capacity is less than design and determined to be insufficient in
and transducers outfitted on injection
conjunction with other inputs, potentially increase the number of wells.
and extraction wells
If well capacity is greater than design and determined to be more than
sufficient in conjunction with other inputs, potentially decrease the number of
wells.
If the observed hydraulic influence is less than anticipated and other
Area of hydraulic influence: estimated via
inputs and updated modeling indicate insufficient influence to meet the
water level change measured in monitoring
problem statement, adjust the flowrates (if capacity is available). If the flowrate
wells in conjunction with operating flowrates
adjustment is insufficient, reconfigure or add to the remedial well network.
at injection and extraction wells, water level
maps, gradient analysis and modeling
results
If hydraulic influence is greater than anticipated, evaluate reducing the
number of wells and/or increasing the well spacing.
Concentration Reductions: measured
via sampling of monitoring wells in key
If the anticipated COI concentration trends are not achieved, first adjust
areas where changes/reductions in
flowrates (if capacity is available). If the flowrate adjustment is insufficient, use
concentration is anticipated. May be of
other inputs to inform reconfiguration and/or additions to the remedial well
limited use during short duration of pilot
network.
test.
Updated groundwater modeling:
revisit groundwater modeling only if data
Update modeling if calculated hydraulic conductivity or other
collected from the pilot study is outside
groundwater parameters significantly deviate from input parameters in existing
of a reasonable variation range from the
numerical models.
inputs used in the existing modeling per
decision rules.
For the proposed hydraulic remedies at the sites, the data inputs, although listed separately here, will be used in conjunction with one another to evaluate
effectiveness of the remedy.

Table 1- Basis of Design Summary
Pilot Test Work Plan
Roxboro Steam Electric Plant
Semora, North Carolina
Approximately 50 gpmpilot-scale 100 gpm total full-scale based on modeling.
Design Objectives Boron, Selenium, Strontium, Sulfate, TDS
• Wells EX-19 to EX-50: 230 to 319 ft AMSL (average = 267 ft AMSL)
Wells EX-51 to EX-59: average 13 ft AMSL
To -be -determined during pilot testing
Ranges from 45 to 75 feet on -center for pilot test wells.
No clean water injection within pilot test.
• Discharge to existing Silo 5 Sump which is then pumped to the Water Redirect Sump then the Lined Retention Basin.
Well water pumps within extraction well network dewater wells to targeted depth, inducing groundwater capture zone.
' • • Extracted water conveyed to existing central discharge point (Silo 5 Sump) for combined flow to the Lined Retention Pond.
Due to extended distances, collection points, referred to as "Node Buildings", will combine the flow from a localized group of extraction wells into a common header. Several collection points
will be located to minimize the length of total piping required and to maximize pumping efficiency. Node Building discharges will combine to form a single final discharge. All instrumentation
and controls will be at the Node Buildings.
Must be commonly available, serviceable, and universally compatible with system controls.
Extraction well pumps will cycle on/off within targeted draw -down depth range (target range set per well).
Flow rates will be controlled manually using a valve.
Pressure transducer with PLC pump control set points, data logging, and operator monitoring.
Instantaneous and totalizing flow measurement for individual wells and combined Node Building discharges prior to discharge to Silo 5 Sump.
All exterior conduit/pipe to be buried whenever possible. Minimize road crossing and overall trenching work. Oversize piping to allow for cleanouts (buried pipe size 2-inch diameter minimum)
Incorporate Node Buildings as common control, metering, and discharge collection centers. Size headers for full-scale ex ansior
Design to integrate discharge into existing systems, without impacting functionality of existing systems.
Not required for conveyance pipe, but required for holding/equalization tanks and leak detection/sump in collection buildings.
Secondary containment 110 % of the holding/equalization tank maximum capacity.
Include water storage, pump, conveyance, and electrical/controls capacity for future expansion in capacity and number of wells. Include spare pipe/conduit in buried installations.
Include spare conveyance pipe/conduit where appropriate for future expansion
• • Design for maximum automation and remote monitoring. Design for full serviceability of all major components (e.g., tru-union fittings, clean -outs, etc.)
Design for all -season operation, including electric heat tracing/insulation of conveyance pipes where required.
Minimize complexity, include fail -safes to prevent spills, to protect the operating equipment, and to allow for automated operation with minimal operator input.
Cellular -based remote monitoring capabilities, allow full remote operation of all systems by approved operator personnel, monitoring only available
• • No controls integration anticipated. Possible dry -contact interlock to existing Silo 5 Sump level instrumentation
Each Node Building to contain dedicated/independent control, but include inter -node communication if required for alarm interlock
41 pilot -scale (59 total full-scale)
Vertical Extraction Wells Minimum Flow Rate: 0.1 gpm pilot -scale (0.1 gpm full-scale)
Average Flow Rate: 0.7 gpm pilot -scale (1.4 gpm full-scale)
Maximum Flow Rate: 2.4 gpm pilot -scale (10.3 gpm full-scale)
' - 6 inches 12-inch diameter borehole
Wells EX-19 to EX-50: Carbon steel
Wells EX-51 to EX-59: Carbon steel
• • • See Table 3
1 /2 to 1 HP electric submersible well pump (e.g. Grundfos Redi-Flo or SQ/SQE or similar
Drillers to install with temporary well box to be modified during system equipment installation.
Precast square concrete vault box with lids (Duty -ratings to be determined during design). Shut-off valve at wellhead.
Carbon steel pipe. Riser pipe 1 to 1.25-inch diameter (sized to match pump outlet).
Groundwater extraction controlled by a PLC with HMI.
Modified intermodal container (a.k.a., CONEX box) or pre -fabricated structure installed on a concrete or stone pad/foundation with appropriate
sized berm for secondary containment if required
Sized to for future expansion capacity and optimized transfer pump cycle -duty. Location (inside or exterior to building) to -be -determined.
Page 1 of 2

Table 1- Basis of Design Summary
Pilot Test Work Plan
Roxboro Steam Electric Plant
Semora, North Carolina
Not required, all heating to be electrical -resistance
•I C.1 03 Not re wired
Not required
All systems protected by keyed locks andpasswords; no video surveillance or fencing required
Acronyms:
amsl = above mean sea level
bgs = below ground surface
CAP = Corrective Action Plan
ft = feet
gpm = gallons per minute
HMI = human -machine interface
HP = horsepower
HPDE = high density polyethylene
PLC = programable logic controller
PVC = polyvinyl chloride
SS = stainless steel
TDS = total dissolved solids
Page 2 of 2

Table 3 - Proposed Well Construction Details
Pilot Test Work Plan
Roxboro Steam Electric Plant
Semora, North Carolina
i aoie s - rroposea vveu t onstrucuon ueiaus
Surface Casing
Surface
Approximate
Borehole Open Borehole
Total
Fasting
Northing
Surface Casing
Borehole
Casing
Surface CasingDiameter
Depth
Depth
Additional Notes
(NAD 83)
(NAD 83)
Material
Diameter
Diameter
Depth
(inches)
(inches)
(ft bgs)
(inches)
(ft bgs)
(ft bgs)
EX-19
Extraction
Bedrock
South of Storm
1981697.60
994527.90
Steel
14 - 16
12 - 14
0 - 55
10 - 12
55 - 220
220
Addresses EAB Source Area
Water Pond
EX-20
Extraction
Bedrock
South of Storm
1981725.00
994495.40
Steel
14 - 16
12 - 14
0 - 55
10 - 12
55 - 220
220
Addresses EAB Source Area
Water Pond
EX-21
Extraction
Bedrock
South of Storm
1981844.80
994461.70
Steel
14 - 16
12 - 14
0 - 55
10 - 12
55 - 220
220
Addresses EAB Source Area
Water Pond
EX-22
Extraction
Bedrock
South of Storm
1981915.90
994483.00
Steel
14 - 16
12 - 14
0 - 55
10 - 12
55 - 220
220
Addresses EAB Source Area
Water Pond
EX-23
Extraction
Bedrock
South of Storm
1981969.50
994502.90
Steel
14 - 16
12 - 14
0 - 55
10 - 12
55 - 220
220
Addresses EAB Source Area
Water Pond
EX-24
Extraction
Bedrock
South of Active
1982709.12
994507.38
Steel
14 - 16
12 - 14
0 - 50
10 - 12
50 - 280
280
Addresses EAB Source Area
Borrowing Area
EX-25
Extraction
Bedrock
South of Active
1982776.43
994501.26
Steel
14 - 16
12 - 14
0 - 50
10 - 12
50 - 280
280
Addresses EAB Source Area
Borrowing Area
EX-26
Extraction
Bedrock
South of Active
1982844.98
994487.80
Steel
14 - 16
12 - 14
0 - 50
10 - 12
50 - 280
280
Addresses EAB Source Area
Borrowing Area
EX-27
Extraction
Bedrock
South of Active
1982562.37
994453.54
Steel
14 - 16
12 - 14
0 - 50
10 - 12
50 - 280
280
Addresses EAB Source Area
Borrowing Area
EX-28
Extraction
Bedrock
South of Active
1982626.70
994456.30
Steel
14 - 16
12 - 14
0 - 50
10 - 12
50 - 280
280
Addresses EAB Source Area
Borrowing Area
EX-29
Extraction
Bedrock
South of Active
1982694.60
994457.45
Steel
14 - 16
12 - 14
0 - 50
10 - 12
50 - 280
280
Addresses EAB Source Area
Borrowing Area
EX-30
Extraction
Bedrock
South of Active
1982741.31
994453.05
Steel
14 - 16
12 - 14
0 - 50
10 - 12
50 - 280
280
Addresses EAB Source Area
Borrowing Area
EX-31
Extraction
Bedrock
South of Active
1982799.48
994448.64
Steel
14 - 16
12 - 14
0 - 50
10 - 12
50 - 280
280
Addresses EAB Source Area
Borrowing Area
EX-32
Extraction
Bedrock
South of Active
1982848.84
994423.96
Steel
14 - 16
12 - 14
0 - 50
10 - 12
50 - 280
280
Addresses EAB Source Area
Borrowing Area
EX-33
Extraction
Bedrock
SE of Active
1982909.65
994408.98
Steel
14 - 16
12 - 14
0 - 50
10 - 12
50 - 280
280
Addresses EAB Source Area
Borrowing Area
EX-34
Extraction
Bedrock
South of Active
1982979.28
994363.15
Steel
14 - 16
12 - 14
0 - 50
10 - 12
50 - 280
280
Addresses EAB Source Area
Borrowing Area
EX-35
Extraction
Bedrock
SE of Active
1983022.98
994344.06
Steel
14 - 16
12 - 14
0 - 50
10 - 12
50 - 280
280
Addresses EAB Source Area
Borrowing Area
EX-36
Extraction
Bedrock
South of Active
1983123.83
994272.36
Steel
14 - 16
12 - 14
0 - 50
10 - 12
50 - 280
280
Addresses EAB Source Area
Borrowing Area
EX-37
Extraction
Bedrock
SE of Active
1983239.46
994259.92
Steel
14 - 16
12 - 14
0 - 50
10 - 12
50 - 280
280
Addresses EAB Source Area
Borrowing Area
EX-38
Extraction
Bedrock
South of Active
1983290.43
994277.67
Steel
14 - 16
12 - 14
0 - 50
10 - 12
50 - 280
280
Addresses EAB Source Area
Borrowing Area
EX-39
Extraction
Bedrock
South of DFA
1980731.30
994666.20
Steel
14 - 16
12 - 14
0 - 45
10 - 12
45 - 220
220
Addresses EAB Source Area
Handling Area
EX-40
Extraction
Bedrock
South of DFA
1980801.30
994675.50
Steel
14 - 16
12 - 14
0 - 45
10 - 12
45 - 220
220
Addresses EAB Source Area
Handling Area
EX-41
Extraction
Bedrock
South of DFA
1980861.90
994679.00
Steel
14 - 16
12 - 14
0 - 45
10 - 12
45 - 220
220
Addresses EAB Source Area
Handlin Area
Page 1 of 2

Table 3 - Proposed Well Construction Details
Pilot Test Work Plan
Roxboro Steam Electric Plant
Semora, North Carolina
i aoie s - vroposea well t onstrucuon ueiaus
Surface Casing
Surface
Approximate
Borehole Open Borehole
Total
Fasting
Northing
Surface Casing
Borehole
Casing
Surface CasingDiameter
Depth
Depth
Additional Notes
(NAD 83)
(NAD 83)
Material
Diameter
Diameter
Depth
(inches)
(inches)
(ft bgs)
(inches)
(ft bgs)
(ft bgs)
EX-42
Extraction
Bedrock
South of DFA
1980914.09
994668.87
Steel
14 - 16
12 - 14
0 - 45
10 - 12
45 - 220
220
Addresses EAB Source Area
Handling Area
EX-43
Extraction
Bedrock
South of DFA
1980948.96
994632.43
Steel
14 - 16
12 - 14
0 - 35
10 - 12
35 - 220
220
Addresses EAB Source Area
Handling Area
EX-44
Extraction
Bedrock
South of DFA
1980986.04
994605.55
Steel
14 - 16
12 - 14
0 - 35
10 - 12
35 - 220
220
Addresses EAB Source Area
Handling Area
EX-45
Extraction
Bedrock
South of DFA
1981023.07
994578.62
Steel
14 - 16
12 - 14
0 - 35
10 - 12
35 - 220
220
Addresses EAB Source Area
Handling Area
EX-46
Extraction
Bedrock
South of DFA
1981111.79
994561.65
Steel
14 - 16
12 - 14
0 - 35
10 - 12
35 - 220
220
Addresses EAB Source Area
Handling Area
EX-47
Extraction
Bedrock
South of DFA
1981165.10
994569.92
Steel
14 - 16
12 - 14
0 - 35
10 - 12
35 - 220
220
Addresses EAB Source Area
Handling Area
EX-48
Extraction
Bedrock
South of DFA
1981221.60
994590.86
Steel
14 - 16
12 - 14
0 - 35
10 - 12
35 - 220
220
Addresses EAB Source Area
Handling Area
EX-49
Extraction
Bedrock
In DFA Handling
1981080.60
994718.58
Steel
14 - 16
12 - 14
0 - 35
10 - 12
35 - 220
220
Addresses EAB Source Area
Area
EX-50
Extraction
Bedrock
In DFA Handling
1981050.45
994749.95
Steel
14 - 16
12 - 14
0 - 35
10 - 12
35 - 220
220
Addresses EAB Source Area
Area
EX-51
Extraction
Bedrock
SE of Active
1983344.46
994299.44
Steel
14 - 16
12 - 14
0 - 55
10 - 12
55 - 526
526
Addresses EAB Source Area
Borrowing Area
EX-52
Extraction
Bedrock
SE of Active
1983426.28
994280.71
Steel
14 - 16
12 - 14
0 - 55
10 - 12
55 - 517
517
Addresses EAB Source Area
Borrowing Area
EX-53
Extraction
Bedrock
SE of Active
1983496.84
994256.72
Steel
14 - 16
12 - 14
0 - 55
10 - 12
55 - 501
501
Addresses EAB Source Area
Borrowing Area
EX-54
Extraction
Bedrock
SE of Active
1983533.53
994215.80
Steel
14 - 16
12 - 14
0 - 55
10 - 12
55 - 509
509
Addresses EAB Source Area
Borrowing Area
EX-55
Extraction
Bedrock
SE of Active
1983556.11
994166.41
Steel
14 - 16
12 - 14
0 - 55
10 - 12
55 - 516
516
Addresses EAB Source Area
Borrowing Area
EX-56
Extraction
Bedrock
SE of Active
1983585.75
994109.96
Steel
14 - 16
12 - 14
0 - 55
10 - 12
55 - 522
522
Addresses EAB Source Area
Borrowing Area
EX-57
Extraction
Bedrock
SE of Active
1983566.96
994032.81
Steel
14 - 16
12 - 14
0 - 55
10 - 12
55 - 530
530
Addresses EAB Source Area
Borrowing Area
EX-58
Extraction
Bedrock
SE of Active
1983634.30
994015.60
Steel
14 - 16
12 - 14
0 - 55
10 - 12
55 - 531
531
Addresses EAB Source Area
Borrowing Area
EX-59
Extraction
Bedrock
SE of Activ
1983722.10
994007.70
Steel
14 - 16
12 - 14
0 - 55
10 - 12
55 - 536
536
Addresses EAB Source Area
BorrowArea
in e
Notes:
it bgs: Feet below ground surface
NAD: North American Datum
Page 2 of 2

Table 4 - Effectiveness Monitoring Plan Summary
Pilot Test Work Plan
Roxboro Steam Electric Plant
Semora, North Carolina
Table 4 -Effectiveness Monitoring Plan Summary
Source - Table 6-16 from CAP Update
Effectiveness Monitoring Plan (EMP) Post -Closure Monitoring Plan (PCMP)
Implemented 30 days after CAP Approval Implemented after completion of ash basin closure activities
EMP Groundwater Well Monitoring Network
(background, downgradient of source areas)
CCR-112BR-BG1 GMW-10 MW-27BR
Y
`o
MW-14BR1 GMW-11 MW-28BR
3
y
MW-198RL1 GPMW-SBR MW-346R
Z
MW-29BR1 GPMW-1D MW-34D
a
c
`o
MW-30BR1 GPMW-1S MW-35BR
•�
CCR-103BR GPMW-2BR MW-35D
i
CCR-104BR GPMW-2D MW-35S
d
CCR-105BR GPMW-3BR MW-36BR
CCR-106BR GPMW-3D MW-36D
a
c
0
CCR-107BR MW-1BR MW-37BR
CCR-108BR MW-1BRL MW-37D
t7
CW-1 MW-3BR MW-37S
GMW-2 MW-22BR MW-108BRL
GMW-6 MW-22D MW-108BRLL
T
w
or
w
U.
a
c
Or
H
`u
d
E
m
`m
a
a
c
.a
E
m
In
EMP Groundwater Qua Iitya' 4
(Semi -Annual Sampling Frequency)
Alkalinity Ferrous Iron Sodium
Aluminum Iron Strontium
Bicarbonate Alkalinity Magnesium Sulfate'
Boron Manganese Total Dissolved Solids'
Calcium Nitrate + Nitrite Total Organic Carbon
Selenium Potassium
PCMP Groundwater Well Monitoring Network
(background, downgradient of source areas)
A PCMP will be implemented at the Site in accordance with
G.S. 130A-309.214(a)(4)k.2 after completion of
ash basin closure activities.
PCMP Groundwater Quality
(Sampling frequency to be determined)
Parameters and sampling frequency to be included in the PCMP in accordance
with G.S. 130A-309.214(a)(4)k.2 when submitted.
EMP and PCMP Groundwater Field Parameters
Water Level Specific Conductivity Temperature
pH Oxidation Reduction Potential Dissolved Oxygen
EMP Review
Annual Effectiveness Monitoring Evaluation and Reporting
1) Summary of annual groundwater monitoring results
2) Evaluate statistical concentration trends
2) Comparison of observed concentrations to model predictions
3) Evaluation of compliance with applicable Standards
4) Evaluation of system performance and effectiveness
3) Recommend plan adjustments, if applicable, to optimize the remedial action
5-Year Performance Review Reporting
1) Update background analysis
2) Confirm Risk Assessment assumptions remain valid
3) Re-evaluate effectiveness of technology
4) Verify modeling results, update model if needed
5) Modify corrective action approach, as needed, to achieve compliance goal
established
EMP
E
a
ON 30 days after CAP approval, the EMP will be implemented at the Site and will
° c continue until there is a total of three years of data confirming COIs are below
a applicable Standards at or beyond the compliance boundar
y, at which time a
trequest for completion of active remediation will be filed with NCDEQ.
o O
.E If applicable standards are not met, the EMP will continue and transition to
o post -closure monitoring if necessary.
S
PCMP Review
Annual Evaluation and Reporting:
1) Summary of annual groundwater monitoring results
2) Evaluate statistical concentration trends
2) Comparison of observed concentrations to model predictions
3) Evaluation 02L compliance
4) Recommend plan adjustments, if applicable
At a freauencv no greater than 5 years:
1) Update background analysis
2) Confirm Risk Assessment assumptions remain valid
3) Verify model results, update if needed
After ash basin closure and following ash basin closure certification,
a PCMP will be implemented at the Site for a minimum of 30 years in
accordance with G. S. 130A-309.214(4)(k)(2).
Early termination:
If groundwater monitoring results are below applicable Standards at the
compliance boundary for three years, Duke Energy will request completion of
corrective action in accordance with G.S. 130A-309.214(a)(3)b. If
groundwater monitoring results are above applicable Standards, the PCMP will
continue.
' Approved background groundwater monitoring location
' Geochemically non -reactive constituent (i.e., conservative corrective action COI) that best depicts the areal extent of the plume; monitors plume stability and physical attenuation
' The number of monitoring wells and parameters may be adjusted based on additional data and the effects of corrective action.
4 Groundwater standards may be modified over time in accordance with 02L .0106(k)
s Proposed extraction well to be installed as part of the remedial alternative
Italicized parameters - parameters for general water quality to evaluate monitoring data quality
Wells indicated in red will have geochemical sondes placed to monitor geochemical conditions
EAB - East ash basin
LCID - land clearing and inert debris
GSA - gypsum storage area
DFAHA - dry fly ash silos, transport, and handling area
Page 1 of 1

FIGURES
www.erm.com Project No.: 0550525 Client: Duke Energy Progress, LLC June 23, 2020

-�' .�` �-,rr�S��"''�i.'j.r�r • • _��•-�, � � • tie, L � ! � ,�a .� � ` .11' . -
v�i L • S ,i
IN
M MOM
dof
4 !! 1 •I�:IJ, 1
.v��..It if .•:' f:• •� �s F•� �
"z P _iy 1A
NOTES:
4LA. ikc, 3u xi:` a ., a y 1. SAMPLE LOCATIONS WERE DERIVED FROM VARIOUS SOURCES AND AREA C
� 1 �L,r •• •y i•', _ •ti�..C.� �,. �•;
"'—.. AND APPROXIMATE LOCPSIONS. THEREFORF., SAMPLE LOCATIONS ARE TO BE DEEMED
"t ` APPROXIMATE. _
2. ALL BOUNDARIES ARE APPROXIMATE]
• '. y_ ' 3. DUKE ENERGY PROPERTY LINES ARE REPiRESENTED BASED ON DUKE ENERGY'
INTERPRETATION OF HISTORICAL DOCUMENTED PROPERTY BOUNDARIES AND CURR PERSON',
COUNTY GIS.
" 4. THE WATERS OR THE US DELINEATION HAS NOT BEEN APPROVED BY THE US ARMY CORPS `
ENGINEERS AT THE TIME OF MAP CREATION. THIS MAP IS A PRELIMINARY JURISDICTIONAL
DETERMINATION ONLY. THE PRELIMINARY WETLANDS AND STREAMS BOUNDARIES WERE
OBTAINED FROM AMEC FOSTER WHEELER ENVIROt4MENTAL & INFRASTRUCTURE, INC. NATURA
RESOURCE TECHNICAL REPORT (NRTR) FOR ROX`"BORO STEAM ELECTRIC PLANT DATED JUNE
2015.
5. AERIAL PHOTOGRAPHY OBTAINED FROM GOOGLE EARTH PRO ON OCTOBER 11, 2017. AERIA
1 111
,k WAS COLLECTED ON JUNE 13, 2016. 11 111 f- 1 r , • ,. � � �
4+ 6. DRAWING HAS BEEN SET WITH A PROJECTION OF NORTH CAROLINA STATE PLANE COORDI
_. - .- -n ' -' K '4 •'1l _ '1 - - T _ '� _ o o 7O�lC R Qj � D��pp ��epp }4gpIV�GLN�U AW Q6A OMAR,�—1. s

XIE
dli
Ice line-- -• - - +
�3�►• _
ode building
nveyance lines ,
-ge location independently r.
header.
acent to each other when ever possible..
Ic
FA
intake canal w
EX-8
EX-5r-
GPMW-01S EXp6
GPMW-01 D EX -
MI
GP01 BR
EX-3
EX-1,' �1 r
�" it
MW 34D e
a-
rc EX-49
MW-34BR
,EX-40 EXy41 MW-36D MW-22D MW-22BR p1 �■
I ► v ri *.i J ti� J EX-a2 .. .,i'}
EX39• • ♦,
11.i1 ����� �; � • MW-36113111 l 4 •. i'.K: • _
EX-43,'%•,.EX-48. ..�
' sr EX- EX-47 ,✓� .. '•�,
Ut
EX-45 MW-37S
EX-46 MW EX'25.♦
-37D EX-19 -.0 j. 'EX=24�•
_�
' MW-37BR EX-20 �,`•`,'.'•�• EX-28 - EX:?%.
! MW-35BR MW-35., D r EX-32 'MW-16RL
MW-35D EX-23
GMW-10 �� F EX-2 7 EX-29EX-30 EX-31 MW-01BR
F EX-21 EX22 PC in - EX-33
CCR-1056R 4 CW-01
J .MW-02 " Proposed Node Ex-3a �.
CCR-103BR Bu lding C - SEX-35-•
- � Proposed Node GMW-11 EX-36
Building B - - EX-37'
GMW-06
lit CCR-10413R� CCR-1076R
i
too
PZ-14 �J
ABMW-5 �R _
- ABMW-5D ,
0 125 250 500 ABMW-7
Feet ABMW-7BR
ABnnw-76RLL Source: E-sri, Di.gitalG�l be, GeoEye, Earths4ar G� - graphics, CNES%
n Legend
® Proposed Full Scale Injection Well
• Discharge to Silo 5 Waste Water
Proposed Node Building Disturbance
`u
Proposed Full Scale Extraction Wells
Sump
Area
Y
O Proposed Node Building
Qlndustrial Landfill Area with
y Proposed Pilot Test Extraction Well
Study Node Building
Engineered Liner System
s
Existing Monitoring Well
_Pilot
Conveyance Path
1; Geographic Limitation
a
m
i
—Extraction Well Conveyance Path
,Roxboro Steam Electric Plant
' Property Line
(' DUKE
ENERGY.
MW-29BR MW-29BR
EKED
I-E
TITLE
FIGURE NO.
Full -Scale Design Well Network
XX
6/5/2020
Pilot Test Work Plan
Duke Energy
Roxboro Steam Electric Plant
2
D,ECTMANADER
DA TE
ENVIRONMENTAL RESOURCES MANAGEMENT, INC.
ER �.
M
XX
6/5/2020
Semora, North Carolina
PPFROVED XX
DATE 6/5/2020
DRAWBY S. Vickery
6/5/2020
S IEN
1 " = 250 '
ERMPROJETND
0550525
EV
1

GPMW-02D
--N
GPMW-02BR
AREA
6 "
EX-
_
■Ff
r -
-
_ -=
D MW-22D
IF
MW-22BR-
a
EX-19
AII
�•�
EX-20
EX-22 EX-23
EX-21 AV
GMW-10
.OX PI
CCR-105BR
Proposed Node
_ _
_
Building B
GMW-11
rce: ri, Di.gitalGlobe -o e,
rGhsta
e' g aphics CHENIUThp DS, USDA, Uacc S,
Ae-r�GRID IGN andfihe. @User
mmunity
Legend
®
Proposed Full Scale Injection Well
Proposed Full Scale Extraction Wells
Pilot Test Node Building Conveyance Path
Extraction Well Conveyance Path
Proposed Pilot Test Extraction Well
® Proposed Node Building Disturbance Area
DUKE
Vw E N E RGY,
Existing Monitoring Well
r' �•
Geographic Limitation
Discharge to Silo 5 Waste Water Sump - - i Roxboro Steam Electric Plant Property
0
Proposed Node Building
, - - + Line
N
AREA A
it
MW-27BR e
k
i - — ' EX-24' ' E3('25'
- - - EX-28 EX-261%
. - ---=a
EX-32 `MW-1BRL
EX'27 EX-29 EX-30 EX-31 + MW-016R Proposed Node
�.� Building A
CCR-108BR r' EX-33 CW-01-4.-
EX-34 �• _ EX-51
• EX35 • EX-52
7E
MW-108BRL
,CCR-108BR
MW-108BRL
L
0 125 250 Source:9
Feet Gecgraphi
AeroGRID
CHECKED
DATE
TITLE
FIGURE NO.
RIB
6/5/2020
Pilot Test Remedy and Monitoring Layout
Duke Energy
ENVIRONMENTAL RESOURCES MANAGEMENT, INC.
ERM
Pilot Test Work Plan
Roxboro Steam Electric Plant
3
PROJECT MANAGER
BW
DATE
6/5/2020
APPROVED
WM
DATE
6/5/2020
DRAWNBV S. Vickery
DATE 6/5/2020
1 SCALE 1 " = 200 '
PRMPROJECTNO 0550525
REv 1

P-124 TO P-138 &
P-151 TO P-159
AREA A
EXTRACTION PUMPS
GW EXTRACTION WELLS
EW-24 TO -38 &
EW-51 TO -59
P-119 TO P-123
AREA B
EXTRACTION PUMPS
GW EXTRACTION WELLS
EW-19 TO -23
P-139 TO P-150
AREA C
EXTRACTION PUMPS
GW EXTRACTION WELLS
EW-39 TO -50
F- - - - - - - - - - - - - - - - -
T-201
AREA A
HOLDING P-201
TANK AREA A
TRANSFER PUMP
I— — — — — — — — — — — — — — — J
LIMITS OF AREA A NODE BUILDING
F— — — — — — — —
T-301
AREA B
HOLDING P-301
TANK AREA B
TRANSFER PUMP
I— — — — — — — — — — — — — — — J
LIMITS OF AREA B NODE BUILDING
F- — — — — — — — — — — — — — — — ---
— — — — — — — — — — — — — — — J
LIMITS OF AREA C NODE BUILDING
PROCESS STREAM CHARACTERISTICS
Stream
Description
Flow Conditions
A
Area A Wells (EX-24 to -38, EX-51 to -59)
0.1-6.2 gpm ea.
B
Area A Discharge
"35 gpm
C
Area B Wells (EX-19 to -23)
0.5-0.6 gpm ea.
D
Area B Discharge
"3 gpm
E
Area C Wells (EX-39 to -50)
0.1-2.4 gpm ea.
F
Area C Discharge
—12 gpm
G
Roxboro Pilot Discharge
—50 gpm
gpm - gallons per minute
ea. - each
ft - feet
DRY FLY © WATER
ASH SUMP REDIRECT
(EXISTING) SUMP
LEGEND
EXTRACTION PUMP
TRANSFER PUMP
HOLDING TANK
NOTE: ALL EXTRACTION WELL
INSTRUMENTATION AND CONTROLS,
INCLUDING FLOW METERS, FLOW
CONTROL VALVES, VALVES, AND
PRESSURE GAUGES, WILL BE CONTAINED
WITHIN EACH NODE BUILDING.
LINED INTERNAL
RETENTION NPDES
BASIN OUTFALL
012
Figure 4
Process Flow Diagram
Pilot Test Work Plan
Roxboro Steam Electric Plant
Semora, North Carolina
Environmental Resources Management
www.erm.com
ERM

LEVEL SWITCH —
CONTROL WIRING
OPEN BEDROCK
BOREHOLE
DEPTH VARIES
BENTONITE CHIPS
MIN. 2 FEET
OPEN BEDROCK
BOREHOLE
DEPTH VARIES
NOT TO SCALE
1-INCH TO 1.25-INCH
DROP PIPE (GALV. STEEL)
EXTRACTION PUMP
POWER LEAD
1.25-INCH TO 1.5 INCH
STILLING WELL
14-INCH OR 16-INCH
BOREHOLE
BENTONITE CEMENT GROUT
IN CASING ANNULUS
12-INCH OR 14-INCH CASING
(STEEL)
BENTONITE CHIP SEAL
AT BOTTOM OF CASING ANNULUS
HIGH LEVEL SWITCH
12-INCH TO 14-INCH OPEN
BEDROCK BOREHOLE
LOW LEVEL SWITCH
CHECK VALVE
ELECTRIC SUBMERSIBLE
WELL PUMP
Figure 5
Groundwater Extraction Well Schematic
Pilot Test Work Plan
Roxboro Steam Electric Plant
Semora, North Carolina
Environmental Resources Management
www.erm.com
ERM

ERM has over 160 offices across the following
countries and territories worldwide
Argentina
The Netherlands
ERM's North Carolina Office
Australia
New Zealand
4140 Parklake Avenue
Belgium
Norway
Suite 110
Brazil
Panama
Raleigh, NC 27612
Canada
Peru
Chile
Poland
T: 919.233.4501
China
Portugal
F: 919.578.9044
Colombia
Puerto Rico
France
Romania
www.erm.com
Germany
Russia
Ghana
Senegal
Guyana
Singapore
Hong Kong
South Africa
India
South Korea
Indonesia
Spain
Ireland
Sweden
Italy
Switzerland
Japan
Taiwan
Kazakhstan
Tanzania
Kenya
Thailand
Malaysia
UAE
Mexico
UK
Mozambique
US
Myanmar
Vietnam
The business of sustainability ERM