Marshall Pumping Test Work Plan - Rev1_05 24 18

PUMPING TEST
WORK PLAN
FOR
MARSHALL STEAM STATION
8320 EAST CAROLINA HIGHWAY 150
TERRELL, NORTH CAROLINA 28682

SUBMITTED: MAY 2018

REVISION 1

PREPARED FOR

DUKE ENERGY CAROLINAS, LLC

Christopher H. Bruce, NC LG 2246
Sr. Geologist

Brian Wilker, NC LG 2546
Project Manager
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TABLE OF CONTENTS
SECTION PAGE
INTRODUCTION ......................................................................................................... 1-1 1.0
Site History, Operations, and Coal Ash Management ........................................ 1-1 1.1
Planned Pumping Tests ........................................................................................... 1-2 1.2
SITE CONCEPTUAL MODEL ................................................................................... 2-1 2.0
Site Geology and Hydrogeology ............................................................................ 2-1 2.1
2.1.1 Site Geology ......................................................................................................... 2-1
2.1.2 Site Hydrogeology .............................................................................................. 2-1
WELL INSTALLATION .............................................................................................. 3-1 3.0
Installation of Pumping and Observation Wells .................................................. 3-1 3.1
3.1.1 Ash Pumping Well Installation ......................................................................... 3-1
3.1.2 Saprolite Pumping Well Installation ................................................................ 3-2
3.1.3 Ash Observation Well Installation ................................................................... 3-2
3.1.4 Saprolite Observation Well Installation ........................................................... 3-3
Well Development .................................................................................................... 3-4 3.2
PUMPING TESTS ......................................................................................................... 4-1 4.0
Static Water Level Collection .................................................................................. 4-1 4.1
Pumping System Installation .................................................................................. 4-1 4.2
Step-Drawdown Tests .............................................................................................. 4-2 4.3
Step-Drawdown Test Recovery .............................................................................. 4-3 4.4
Constant-Rate Pumping Test .................................................................................. 4-3 4.5
WATER QUALITY MEASUREMENTS AND SAMPLING ................................. 5-1 5.0
ANALYSIS OF WATER LEVEL DATA .................................................................... 6-1 6.0
Baseline Analysis....................................................................................................... 6-1 6.1
Step-Drawdown Test Analysis ............................................................................... 6-1 6.2
Constant Discharge Rate Test Analysis ................................................................. 6-1 6.3
REFERENCES ................................................................................................................ 7-1 7.0
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LIST OF FIGURES
Figure 1 Site Location Map
Figure 2 Marshall Plant Vicinity Map
Figure 3 Location for AB-12 Well Cluster Pumping Test
Figure 4 Location for AB-15 Well Cluster Pumping Test
Figure 5 Location for AB-18 Well Cluster Pumping Test
Figure 6 Typical Flow Meter Configuration
Figure 7 Typical Step Test Drawdown Curve

LIST OF TABLES
Table 1 Well Construction Details
Table 2 Summary of Pumping and Observation Wells

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INTRODUCTION 1.0
Duke Energy Carolinas, LLC (Duke Energy) owns and operates the Marshall Steam
Station (MSS, the Plant, or the Site), located at 8320 NC Highway 150 East in Terrell,
Catawba County, North Carolina (Figure 1). Operations, as a coal-fired generating
station, began at MSS in 1965. Four coal-fired units presently are in operation. Coal
combustion residuals (CCR) consisting of bottom and fly ash material from MSS have
historically been managed in the Site ash basin, located north of the station adjacent to
Lake Norman.
Site History, Operations, and Coal Ash Management 1.1
Marshall Steam Station (MSS) is a four-unit, coal-fired electricity-generating facility
located on the west bank of Lake Norman near the town of Terrell, Catawba County,
North Carolina. The entire Site, approximately 1,446 acres in area, is owned by Duke
Energy. The Site is thought to have been largely undeveloped prior to Duke Energy
ownership.
Coal is delivered to the station by a railroad line. Operation of Unit 1 began in 1965, and
operation of Unit 2 began in 1966, with each generating 350 megawatts. Operation of
Unit 3 began in 1969, and operation of Unit 4 began in 1970, with each generating 648
megawatts. Improvements to the Plant since 1970 have increased the electric generating
capacity to 2,090 megawatts.
The MSS ash basin, which contains ash generated from the historic and active coal
combustion at the Plant, is situated with MSS to the south, topographic divides located
along Sherrills Ford Road to the west, Island Point Road to the north, and Duke Energy
property to the east (Figure 1). The ash basin, approximately 394 acres in size, was
constructed with an earthen dike. A 500-foot compliance boundary for the National
Pollutant Discharge Elimination System (NPDES) groundwater monitoring well
network encircles the ash basin, co-located with the property boundary on the western
edge of the Site and extending to Lake Norman on the eastern edge of the Site (Figure
2). Fly ash and bottom ash from MSS was managed in the ash basin from approximately
1965 until 1984. Fly ash precipitated from flue gas and bottom ash collected in the
bottom of the boilers was sluiced to the ash basin using conveyance water withdrawn
from Lake Norman. Since 1984, fly ash has been disposed of in the on-site landfills and
bottom ash has continued to be sluiced to the ash basin.
Detailed descriptions of the Site operational history, the Site conceptual model, physical
setting and features, geology/hydrogeology, and results of the findings of the
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Comprehensive Site Assessment (CSA) and other Coal Ash Management Act (CAMA)-
related work are documented in full in the following documents:
Comprehensive Site Assessment Report - Marshall Steam Station Ash Basin (HDR,
September 8, 2015a).
Corrective Action Plan Part 1 - Marshall Steam Station Ash Basin (HDR, December 7,
2015b)
Corrective Action Plan Part 2(included CSA Supplement 1 as Appendix A) – Marshall
Steam Station Ash Basin (HDR, March 3, 2016a).
Comprehensive Site Assessment Supplement 2 - Marshall Steam Station Ash Basin
(HDR, August 4, 2016b).
2018 Comprehensive Site Assessment Update – Marshall Steam Station (SynTerra,
January 31, 2018)
Planned Pumping Tests 1.2
Ash basin pumping tests are planned to collect site specific data to further refine the
groundwater flow and transport model to be used for closure planning and potential
groundwater corrective action evaluation. The pumping tests would focus on
evaluation of field scale horizontal and vertical variability of the hydrologic
characteristics for the saturated media. Each test would provide estimates of media
properties including transmissivity (T), hydraulic conductivity (K), and storativity (S).
The following major tasks are anticipated for conducting ash basin pumping tests at the
Marshall Steam Station:
1. Well Installation and Development
2. Static Water Level (Baseline Data) Collection
3. Pumping System Installation
4. Step-Drawdown Tests
5. Step Drawdown Test Recovery
6. Constant Rate Pumping Tests
7. Water Quality Sampling
8. Data Analysis
As a portion of this scope of work, both pumping wells and observation wells have
been installed at the Site (Table 1). A total of three ash pumping wells and one saprolite
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pumping well have been installed at selected locations (Figures 3-5). Each pumping
well was screened either wholly within ash or the underlying soil. A total of 10 new
observation wells have also been installed. Additionally, 23 existing wells would be
utilized as observation points during the ash pumping tests (Table 2). Distance
measurements from pumping wells are approximate and will vary based on site-
specific factors (i.e., limited space for wells). The newly installed well locations have not
been surveyed.
Newly Installed Wells:
AB-12 Well Cluster
AB-12 PWA (ash pumping well), AB-12 OWAU (upper ash observation well 15 feet
from pumping well), AB-12 OWAM (medium ash observation well 15 feet from
pumping well), AB-12 OWAL (lower ash observation well 15 feet from pumping well),
AB-12 OWAM(30) (medium ash observation well 30 feet from pumping well)
AB-15 Well Cluster
AB-15 PWA (ash pumping well), AB-15 OWAU (upper ash observation well 15 feet
from pumping well), AB-15 OWAL (lower ash observation well 15 feet from pumping
well)
AB-18 Well Cluster
AB-18 PWA (ash pumping well), AB-18 PWS (saprolite pumping well), AB-18 OWAU
(upper ash observation well 15 feet from pumping well), AB-18 OWAL (lower ash
observation well 15 feet from pumping well), AB-18 OWAL(30) (lower ash observation
well 30 feet from pumping well), AB-18DU (saprolite observation well 30 feet from
pumping well)
Existing Wells (at pumping test well clusters):
AB-12 Well Cluster
AB-12S (upper ash observation well 30 feet from pumping well), AB-18SL (lower ash
observation well 30 feet from pumping well), AB-12D (transition zone observation well
30 feet from pumping well), AB-12BR (bedrock observation well 30 feet from pumping
well)
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AB-15 Well Cluster
AB-15S (upper ash observation well 30 feet from pumping well), AB-15SL (lower ash
observation well 30 feet from pumping well), AB-15D (transition zone observation well
30 feet from pumping well), AB-15BR (bedrock observation well 30 feet from pumping
well)
AB-18 Well Cluster
AB-18S (upper ash observation well 30 feet from pumping well), AB-18D (transition
zone observation well 30 feet from pumping well)
Additional observation wells located beyond the pumping test well clusters are
proposed to be manually gauged for water levels during the constant rate pumping
tests. Please refer to Table 1 and Table 2 for the list of these wells and for which tests
they will be monitored.
One pumping test is estimated to take eight (8) days (72 hours for static conditions, 24
hours for step test/recovery, 72 hours for constant rate discharge test, 24 hours
recovery). During this time, water levels would be monitored in selected wells using
pressure transducers and manual water level readings. Groundwater samples would
also be collected daily throughout the 72-hour constant rate pumping test for laboratory
analysis, as well as one initial sample collected prior to the step test.
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SITE CONCEPTUAL MODEL 2.0
Site Geology and Hydrogeology 2.1
This section provides a brief summary of the Site geology and hydrogeology. A
detailed description of the Site geology and hydrogeology can be found in the
documents listed in Section 1.
2.1.1 Site Geology
The subsurface at MSS is comprised of a surficial unit (soil, fill and reworked
soil, alluvium, and saprolite), a transition zone, and fractured bedrock. The
transition zone is comprised of partially weathered rock that is gradational
between saprolite and competent bedrock. The bedrock is dominantly mica
gneiss, meta-granite, and quartz-sericite schist. Shallow bedrock is fractured;
however, only mildly productive fractures (providing water to wells) were
observed within the top 50 – 75 feet of bedrock in previous investigations.
Typically, the majority of fractures are relatively small (e.g., close and tight) and
appear to be limited in connectivity between borings. Yields from pumping or
packer testing are generally low. Groundwater exists under unconfined or water
table conditions throughout the Site. Generally, groundwater is contained within
fractures (secondary porosity) of the underlying bedrock.
The fractured bedrock is overlain by a mantle of unconsolidated material known
as regolith. The regolith includes residual soil and saprolite zones and, where
present, alluvial deposits. Saprolite, the product of chemical weathering of the
underlying bedrock, is typically composed of clay and coarser granular material
and reflects the texture and structure of the rock from which it was formed. The
weathering products of granitic rocks are quartz-rich and sandy textured. Rocks
poor in quartz and rich in feldspar and ferro-magnesium minerals form a more
clayey saprolite.
2.1.2 Site Hydrogeology
The soil/saprolite regolith and the underlying fractured bedrock represent a
composite water-table aquifer system. The regolith provides the majority of
water storage. Based on previous investigations, the groundwater system in
natural materials (soil, soil/saprolite, and bedrock) at the MSS site is consistent
with the regolith-fractured rock system and is an unconfined, connected aquifer
system. Regolith is underlain by a transition zone (TZ) of weathered rock that
transitions to competent bedrock. The groundwater system at the MSS site is
divided into three flow layers referred to in this report as the shallow, deep (TZ),
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and bedrock layers, so as to distinguish unique characteristics of the connected
aquifer system.
The hydrogeologic characteristics of the ash basin environment are the primary
control mechanisms on groundwater flow and constituent transport. The stream
valley in which the ash basin was constructed is a distinct slope-aquifer system
in which flow of groundwater into the ash basin and out of the ash basin is
restricted to the local flow regime. Localized topographic relief results in
adjacent groundwater divides associated with the natural ridges separating
historic draws. Groundwater flows generally from the northwest to southeast
across the Site. Active sluicing contributes to free-standing water within the ash
basin and is controlled downgradient by the ash basin dam and the NPDES
outfall/discharge to Lake Norman (east side of ash basin).
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WELL INSTALLATION 3.0
SynTerra conducted field oversight of drilling operations and well installations at the
proposed pumping test locations. SynTerra’s oversight included documentation of field
observations and activities associated with boring advancement, well installation and
well development activities conducted by a licensed North Carolina driller and support
crew contracted by Duke Energy. Pumping well and observation well locations, a
conceptual well layout, and cross-sectional view are provided on Figures 3 through 5.
A summary of well construction details for the pumping wells and observation wells is
included in Table 1.
Installation of Pumping and Observation Wells 3.1
The pumping and observation wells were installed in April 2018 by a licensed North
Carolina driller using rotary sonic drilling techniques. Continuous cores were obtained
at each boring location for lithologic description. All newly installed wells were
completed with concrete well pads, protective surface casings, well tags and locking
caps in accordance with 15A NCAC 02C requirements. Approximate well construction
details are summarized on Table 1. At the time this work plan was written, the newly
installed wells had not yet been surveyed for horizontal and vertical control. Boring
logs and well construction records will be included as part of a technical memorandum
on the results of pumping tests, as referenced in Section 6.
3.1.1 Ash Pumping Well Installation
Ash pumping wells were installed using sonic drilling techniques utilizing a
nominal 13-inch core barrel. Ash pumping wells were installed approximately 30
feet away from existing well clusters AB-12, AB-15 and AB-18. Ash pumping
wells at AB-12, AB-15 and AB-18 well clusters were drilled to approximately 45
feet below ground surface (bgs), 50 feet bgs and 35 feet bgs, respectively (Table
1). All three ash pumping wells were installed with screens located wholly
within the ash layer with no borehole connectivity to the underlying soil.
The wells were constructed of 6-inch ID, National Sanitation Foundation (NSF)
grade polyvinyl chloride (PVC) (ASTM D-1785-12) schedule 40 flush-joint
threaded casing terminating in a 10 foot long 0.010-inch machine-slotted wire-
wrapped PVC screen, hung approximately one foot off the bottom of the boring
(to allow filter material below the well screen).
Packed well screens for each well were filled with clean, well-rounded, washed
high grade No. 1 silica sand. The filter pack extended approximately 2-3 feet
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above the top of the screen. An approximate 2-3 foot pelletized bentonite seal
was placed above the filter pack. The pellets were allowed to hydrate in
accordance with manufactures specifications before grouting the remainder of
the annular space was filled with Agua Guard cement grout from the top of the
upper bentonite seal to near ground surface.
Well construction details are summarized on Table 1. These ash pumping wells
are planned to be abandoned at the conclusion of the pumping test activities.
3.1.2 Saprolite Pumping Well Installation
One saprolite pumping well was installed at the AB-18 well cluster location
adjacent to the ash pumping well. This well was installed using temporary steel
outer drill-string casing as a precautionary measure to prevent potential
migration from overlying material along annular space of the borehole and
beneath the ash-soil interface. Multiple drill string rods/casings were used to
construct the saprolite pumping well. The largest diameter casing was a nominal
13-inch casing that was advanced a few feet into saprolite beyond the base of the
ash. This casing was left in-place for the remainder of well construction
activities. After removing material within the 13-inch casing, drilling resumed to
the targeted depth using smaller diameter casing (nominal 10-inch diameter) to
install the well into saprolite.
Once at targeted depth, the well was constructed similar to the ash pumping
wells, but with the bentonite seal extending from the top of the filter pack up into
13-inch casing and above the approximate depth of the ash/soil interface. After
the bentonite seal was hydrated, the remainder of the annular space was filled
with Agua Guard cement grout from the top of the upper bentonite seal to near
ground surface and the 13-inch steel casing was removed.
Well construction details are summarized on Table 1. The saprolite pumping
well was screened wholly within the soil beneath the ash basin and is planned to
be abandoned at the conclusion of the pumping test activities.
3.1.3 Ash Observation Well Installation
Nine (9) ash observation wells were installed at the site. Four ash observation
wells were installed at the AB-12 well cluster location (Figure 3); two were
installed at the AB-15 well cluster (Figure 4); and three were installed at the AB-
18 well cluster (Figure 5). These wells are located at approximately either 15 or 30
feet away from the pumping well. Approximate distance from the pumping well
for each observation well is provided on Table 1.
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Ash observation wells were installed utilizing a nominal 6-inch core barrel. The
wells were constructed of 2-inch ID, NSF-grade PVC schedule 40 flush-joint
threaded casing terminating in a 5-foot long 0.010-inch machine-slotted pre-
packed PVC screen, hung approximately one foot off the bottom of the boring (to
allow filter material below the well screen).
Packed well screens for each well were filled with clean, well-rounded, washed
high grade No. 1 silica sand. The filter pack extended approximately 2-3 feet
above the top of the screen. An approximate 2-3 foot pelletized bentonite seal
was placed above the filter pack. The pellets were allowed to hydrate in
accordance with manufactures specifications before grouting the remainder of
the annular space was filled with Agua Guard cement grout from the top of the
upper bentonite seal to near ground surface.
Well construction details are summarized on Table 1. These ash observation
wells are planned to be abandoned at the conclusion of the pumping test
activities.
3.1.4 Saprolite Observation Well Installation
One saprolite observation well was installed at the AB-18 well cluster. This well
was installed similar to the saprolite pumping well, using temporary steel drill-
string casing as a precautionary measure to prevent potential migration from
overlying material along annular space of the borehole and beneath the ash-soil
interface. Multiple drill string rods/casings were used to construct the saprolite
observation well.
The largest diameter casing was a nominal 8-inch casing that was advanced a
few feet into saprolite, beyond the base of the ash. This casing was left in-place
for the remainder of well construction activities. After removing material within
the 8-inch casing, drilling resumed to the targeted depth using smaller diameter
casing (nominal 6-inch) to install the well into saprolite. A 2-inch diameter PVC
well was then installed in a similar approach as ash observation wells as
described above. After the bentonite seal was hydrated, the remainder of the
annular space was filled with Agua Guard cement grout from the top of the
upper bentonite seal to near ground surface and the 8-inch steel casing was
removed.
Well construction details are summarized on Table 1.
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Well Development 3.2
The newly installed wells were developed until discharge was clear and stable. The
main objective of the well development was to improve near-well permeability and
stability. Removal of the fine particles from the near-well area would help create a
more permeable zone and minimize the effect of well smear or caking. Improper well
development can cause significant impact to the results of both the step test and the
constant rate pumping test. This could result in the need to stop the test (step test or
constant rate test) and redevelop the wells (primarily pumping wells).
Development included surging and high volume water removal. Completion of
development was determined when turbidity remained below 10 Nephelometric
Turbidity Units (NTUs) after surging the well or at least 10 borehole volumes were
purged.
Turbidity remained greater than 100 NTUs throughout development at several
observation wells, even after several tens of well volumes were removed and extensive
hours of pumping/surging efforts. Observation of cores from these wells indicated the
material was primarily fine-grained (silt), characteristic of fly ash. Well yield was
reasonable, similar to other wells installed in ash, indicating the hydraulic
interconnectivity of these wells may be uninhibited. Therefore, development was
considered complete at these locations.
After development (if any additional development is necessary), the wells would be
allowed to equilibrate for at least five days prior to the collection of baseline water level
data.
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PUMPING TESTS 4.0
Static Water Level Collection 4.1
Static water level (baseline data) collection may commence once the pumping wells and
observation wells have been installed, developed, and allowed to equilibrate (for
approximately five days). Baseline water-level readings would be used to determine
long-term data trends or potential interferences from other pumping/discharge
source(s). Water levels would be monitored in selected wells using pressure
transducers. A summary of the wells to be monitored for each test is included as Table
2.
Prior to the installation of transducers, an initial round of water levels would be
manually collected from the wells listed in Table 2. Transducers would then be
installed and programmed to collect water level data every minute for a minimum of 72
hours before the start of any active pumping (step test). At the end of the 72-hour
period, baseline measurements would be stopped and downloaded for review. Manual
water level measurements will be collected (during certain 72-hour constant rate tests
only) from AB-12BR, AB-15BR, AB-18D, AB-10D/BR, AB-9S/D/BR, AB-8S/D, AB-13D
and AB-16S/D (Table 2).
Pumping System Installation 4.2
Once baseline conditions have been established, a submersible pump would be installed
in the selected pumping well by the Duke well installation contractor. Two pumping
test would be conducted simultaneously. The initial test would be conducted in the
saprolite pumping well at the AB-18 cluster and the ash pumping well at the AB-12 well
cluster. The second test group would be conducted in the ash pumping well at the AB-
15 cluster and the ash pumping well at the AB-18 cluster.
The Duke well installation contractor would provide and install a flow meter capable of
continuously-logging discharge rates and total flow in-line with the pump discharge
line. The flow meter would need to be installed in such a way as to allow it to be full of
water at all times. This can be done by the installation of a six-inch drop in the
discharge line prior to the flow meter and a subsequent 6 inch rise in the discharge line
past the flow meter. A minimum of one foot of straight piping would also need to be
installed after the drop and before the rise to ensure laminar flow through the
transducer. Two ball valves should be installed in the discharge line. One should be
located prior to the drop and one should be located post rise. A photograph showing
the general proposed configuration for the flow meter is presented on Figure 6. A small
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diameter sampling port should also be installed somewhere near the flow meter to
allow for taking field water quality measurements and samples.
The discharge line from AB-12 APW will attempt to be run to the canal east/northeast of
the AB-12 cluster location (Figure 3). However, it may not be physical feasible or safe to
run the line out to this area. The discharge will be placed as close as feasibly possible to
this canal. The discharge from AB-15 APW will be discharged in frac tanks for
temporary storage (assumes three - 21,000 gallon tanks). At the end of the aquifer
testing the water will be discharged to the ground surface (Figure 4). The discharge
from the AB-18 location will be discharged into an area of ponded water approximately
300 feet to the northeast of the well cluster location (Figure 5).
After the completion of the initial set of 72-hour pumping tests, the pump at both
locations would be decontaminated and moved to the second set of test locations (AB-
18 ash pumping well and AB-15 ash pumping well).
Step-Drawdown Tests 4.3
After the pumping system has been installed the well would be allowed to fully recover
(assumed to be 12 hours). Once the pumping wells have fully recovered, SynTerra in
conjunction with the drilling contractor, would conduct a step-drawdown test (initial
test in AB-18 saprolite pumping well and AB-12 ash pumping well).
A step-drawdown test (or step test) is a single-well pumping test designed to
investigate the performance of a pumping well under controlled variable discharge
conditions. During the step-drawdown test, an initial rate of one gallon per minute
(gpm) would be used. The discharge rate would be increased approximately 0.5 gpm
per step period (subject to change based on field observations). Each step would be
approximately 2 hours (subject to change based on field observations). This duration
should allow wellbore storage effects to dissipate. This process would continue until the
well can no longer sustain the selected flow rate (curve does not flatten out) or a
maximum of 20 gpm flow rate is reached. A typical step test drawdown curve is
presented in Figure 7. After completion of the step test, the pumping well would be
allowed to return to static conditions (recovery tests).
Data from the step test would be used to determine an appropriately conservative
initial pumping rate (Qmax) for the constant rate pumping tests. A Qmax should be
calculated that would result in a drawdown after 72 hours that is approximately 25
percent of the water column. At the end of the test the flow would be adjusted to the
selected Qmax using one of the ball valves prior to shutting down the pump. As the
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pump is shut down the remaining ball valve would be closed to prevent the discharge
line from draining into the well (which would affect recovery data).
After the completion of the initial set of 72-hour pumping tests and recoveries, the
pump at both locations would be decontaminated and moved to the second set of test
locations (AB-18 ash pumping well and AB-15 ash pumping well). A second set of step
test would be conducted at these new locations following the same procedure.
Step-Drawdown Test Recovery 4.4
Once the step test is complete, the pump would be shut off and the flow meter would
be isolated (using ball valves upstream and downstream of the flow meter). The well
would be allowed to fully recover prior to the start of the constant discharge test. It is
anticipated that recovery would take less than 12 hours. Water levels would continue
to be monitored at the same frequency during recovery.
Once recovery is complete, the transducers water-level readings would be stopped and
the data downloaded and analyzed.
Constant-Rate Pumping Test 4.5
Once the step-drawdown test has been completed and water levels in the pumping well
and affected observation wells have returned to static conditions and transducers have
been stopped and reprogramed, a constant-rate pumping test would be conducted at
each location (initial two locations AB-18 saprolite pumping well and AB-12 ash
pumping followed by AB-18 ash pumping well and AB-15 ash pumping well). Prior to
the start of any active pumping a round of manual water levels would be collected in
the monitored wells for each test location (Table 2).
A constant-rate pumping test involves a control well that is pumped at a constant rate
while water-level response (drawdown) is measured in one or more surrounding
observation wells and in the pumping well. The goals of a constant-rate pumping test
are to estimate hydraulic properties of a saturated porous media such as T, K, and S and
to identify potential boundary conditions that may exist.
Discharge rates would be measured approximately every 15 minutes during the initial
portion of the test (first four hours). If discharge rate is stable, flow readings may be
conducted at longer intervals (based on field observations). Water level transducers
would be set to record measurements every minute for the duration of the 72-hour test
and recovery period.
Pumping Test Work Plan Revision 1 May 2018
Duke Energy Carolinas, LLC, Marshall Steam Station SynTerra
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Once pumping has started, the test would run uninterrupted for up to 72 hours.
During that period, water-levels would be continuously monitored with data logging
pressure transducers and flow measurements continuously recorded (24 hours per day)
with an electronic flow meter that averages measurements at five minute intervals.
Manual water-level readings would be collected every two hours at each selected well
during active pumping to provide automated data backup (Table 2). Manual flow
measurements may be conducted based on field observations, as described earlier in
this section. Ground water quality field readings and laboratory samples would be
collected from the discharge at selected intervals during active pumping (see Section
4.0).
Pumping Test Work Plan Revision 1 May 2018
Duke Energy Carolinas, LLC, Marshall Steam Station SynTerra
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P:\Duke Energy Carolinas\18. MARSHALL\08.CCP Ash Basin Pumping Test\Work Plan\Marshall Pumping Test Work
Plan_REV1.docx
WATER QUALITY MEASUREMENTS AND SAMPLING 5.0
In order to help identify the potential geochemical changes that may accrue in the water
during the active pumping, water quality data would be collected during each pumping
test. Water quality data would include the collection of both field reading and
laboratory samples. Particular emphasis would be placed on collection of conductivity
and pH data. Changes in water chemistry (conductivity and pH) may indicate contact
with a recharge boundary. Groundwater samples would be collected from the
pumping well discharge and analyzed for IMP constituent list.
Water quality measurements would be collected from the discharge throughout the
constant rate discharge test. Readings of pH, specific conductance, temperature,
dissolved oxygen, oxidation-reduction potential, Eh, and turbidity would be collected
once every hour during the test. To facilitate this, a YSI Pro Plus water-quality meter
would be plumbed into the discharge line. Flow through the meter would be regulated
with both upstream and downstream valves.
Water quality samples for laboratory analysis would be collected prior to the step-
drawdown test and once per day during the constant rate pumping test from each of
the pumping wells. Each sample would be collected from a sampling port plumbed
into the discharge line. Water would be collected in laboratory-prepared sample bottles
and immediately placed on ice under strict chain-of-custody.
Pumping Test Work Plan Revision 1 May 2018
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ANALYSIS OF WATER LEVEL DATA 6.0
Analysis of water level fluctuations in monitoring wells would be initially conducted
using Aqtesolv® Version 4.5. Baseline data, step-drawdown test data, constant rate
discharge data (pumping test), drawdown data, and analytical results would be
summarized and included as part of a technical memorandum on the results of
pumping tests.
Baseline Analysis 6.1
Baseline data would be evaluated to determine whether any long-term trends or
interference from nearby production wells are observable. If long-term data trends are
observed, the baseline data would be used to adjust the pumping test drawdown data
to compensate for the observed trend.
Step-Drawdown Test Analysis 6.2
Step-drawdown test analysis would be conducted in the field. The Theis (1935) step-
drawdown procedure would be used to analyze data. Additional analytical methods
(Dougherty-Badu, 1984; Hantush-Jacob, 1955; Theis, 1935; and Hantush, 1961) may be
used depending on results of the step test drawdown data.
Step test results would be used to calculate a flow rate that would result in a drawdown
of approximately 25 percent of the saturated thickness after 72 hours (and excel spread
sheet would be provided for making these calculations).
Constant Discharge Rate Test Analysis 6.3
Final analysis methods of drawdown data are dependent on actual results of the tests.
Initially, it is assumed that the proposed ash pumping wells are unconfined and the
saprolite pumping well may be unconfined, semi-confined or confined. Additionally,
drawdown may be observed only in the pumping well. This will result in analysis of
the data as a single-well pumping test. If data indicates drawdown in one or more
observation wells, the test will be analyzed as a multiple-well pump test. Suggested
analytical methodologies for data analysis of both single-well and multiple-well pump
tests are outlined in the Technical Guidance Manual for Hydrogeologic Investigations
and Groundwater Monitoring, Chapter 4, Slug and Pumping Test, Table 4.2 (single-well
pump test) and Table 4.7 (multiple-well pump test) (Clemson, February 1995) at:
http://www.clemson.edu/ces/hydro/murdoch/PDF%20
Files/Pumping%20tests,%20EPA%20guidance.pdf

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REFERENCES 7.0
Theis, C.V., 1935. The relation between the lowering of the piezometric surface and the rate and
duration of discharge of a well using groundwater storage, Am. Geophys. Union Trans.,
vol. 16, pp. 519-524.
Dougherty, D.E and D.K. Babu, 1984. Flow to a partially penetrating well in a double
porosity reservoir, Water Resources Research, vol. 20, no. 8, pp. 1116-1122.
Hantush, M.S. and C.E. Jacob, 1955. Non-steady radial flow in an infinite leaky aquifer, Am.
Geophys. Union Trans., vol. 36, pp. 95-100.
Hantush, M.S., 1961b. Aquifer tests on partially penetrating wells, Jour. of the Hyd. Div.,
Proc. of the Am. Soc. of Civil Eng., vol. 87, no. HY5, pp. 171-194.

Pumping Test Work Plan Revision 1 May 2018
Duke Energy Carolinas, LLC, Marshall Steam Station SynTerra

FIGURES

01/18/2018 12:02 PM
P:\Duke Energy Carolinas\18. MARSHALL\CSA Update January 2018\DWG\DE MARSHALL FIG 1-1 (SITE LOC MAP).dwg
FIGURE 1
SITE LOCATION MAP
MARSHALL STEAM STATION
DUKE ENERGY CAROLINAS, LLC
8320 NC HIGHWAY 150 E
TERRELL, NORTH CAROLINA
LAKE NORMAN
SURFACE IMPOUNDMENT BOUNDARY
GRAPHIC SCALE
1000
IN FEET
0 1000 2000
MARSHALL STEAM
STATION PARCEL LINE
SOURCE:
USGS TOPOGRAPHIC MAP OBTAINED FROM THE USGS STORE AT
http://store.usgs.gov/b2c_usgs/b2c/start/%%%28xcm=r3standardpitrex_prd%%%29/.do
ASH BASIN
148 RIVER STREET, SUITE 220
GREENVILLE, SOUTH CAROLINA 29601
PHONE [phone]
www.synterracorp.com
DATE:DRAWN BY: JOHN CHASTAIN
PROJECT MANAGER: BRIAN WILKER
LAYOUT: FIG 1 SITE LOCATION
01/18/2018
MARSHALL
STEAM STATION
FGD LANDFILL
PERMIT NO. 1809
DRY ASH LANDFILL
(PHASE I)
PERMIT NO. 1804
DRY ASH LANDFILL
(PHASE II)
PERMIT NO. 1804
PV STRUCTURAL
FILL
INDUSTRIAL LANDFILL NO. 1
PERMIT NO. 1812
ASH BASIN
LAKE NORM AN
ASH BASIN
FGDRESIDUELANDFILL
PV STRUCTURALFILL
INDUSTRIALLANDFILL #1
C&DLANDFILL
ASH LANDFILL(PHASE II)
ASHLANDFILL(PHASE I)
ASBESTOSLANDFILL
ACCESS ROADSTRUCTURAL FILLBEATTY RDMARSHALL RD
GREENWOOD RD
S
H
E
R
R
IL
L
S F
O
R
D

R
D
NOT ES:
1. IT IS HERE IN NOTED THAT DUKE E NERGY IS NOT WAIVING THE RIGHT TO ACOMPLIANCE BOUNDARY(S ) TO T HE FUL L EXTENT SET OUT IN THE LAW OR ATTEMPTTO IMPAIR THE DEPARTMENT'S ABILITY TO CHANGE THE COMPLIANCE BOUNDARY(S)IN T HE FUT URE, IF CIRCUMSTANCES WARRANT.
2. PROPERTY BOUNDA RY PROVIDED BY DUKE ENERGY CAROLINAS.
3. AERIAL PHOTOGRAPHY OBTAINED FROM GOOGLE EARTH PRO ON SEPTEMBER 12,2017. AERIAL WAS COLLECTED ON OCTOBER 8, 2016.
4. DRAW ING HAS BEEN SET WITH A PROJECTION OF NORTH CAROLINA STATE PLANECOORDINATE SYSTEM FIPS 3200 (NAD83).

FIGURE 2MARSHALL PLANT VICINITY MAPMARSHALL STEAM STATIONDUKE ENERGY CAROLINAS LLC,TERRELL NORTH CAROLINA,
DRAWN BY: B. YOUNGPROJECT MANAGER: B. WILKER CHECKED BY: B. WILKER
DATE: 01/03/2018
148 R IVER STRE ET, SUITE 220GREENVILLE, S OUTH CAROLINA 29601PHONE [phone]www.synterracorp.com
P:\Du ke En erg y P ro g re ss.1026\0 0 GIS BA SE DATA\Ma rshall\Ma p d ocs\CSA_Supplement_2\Fig02-01 - Plant Vicinity Map.mxd
600 0 600 1,200300
GRAPHIC SCALE IN FEET
ASH BASIN WASTE BOUNDARY
ASH BASIN COMPLIANCE BOUNDARY
LANDFILL BOUNDARY
STRUCTURAL FILL BOUNDARY
LANDFILL COMPLIANCE BOUNDARY
DUKE ENERGY CAROLINAS MARSHALL PLANTSITE BO UNDARY
<STREAM (AMEC NRTR 2015)
WETLAND (MCKIM AN D CREED 2016)
LEGEND
CONCEPTUAL LAYOUT, ACTUAL LOCATIONS FOR
WELLS HAVE NOT BEEN SURVEYED
LEGEND
If PROPOSED OBSERVATION WELL (UPPER ASH PORE WATER)
PROPOSED OBSERVATION WELL (MEDIUM ASH PORE WATER)
PROPOSED OBSERVATION WELL (LOWER ASH PORE WATER)
PROPOSED OBSERVATION WELL (SAPROLITE)
PROPOSED PUMPING WELL (ASH PORE WATER)
® PROPOSED PUMPING WELL (SAPROLITE)
S AB-15BR
WELL IN BEDROCK
IS AB-15SL
WELL IN ASH PORE WATER
AB-15D
WELL IN TRANSITION ZONE
CCR-15S
WELL IN SAPROLITE
AQUIFER TEST DISCHARGE LINE AND DIRECTION OF FLOW
ASH BASIN WASTE BOUNDARY (APPROXIMATE)
BGS BELOW GROUND SURFACE
CONCEPTUAL PROPOSED PUMPING TEST
WELL SCHEMATIC
AB-12
AB-12 0
AB-12 OWA,
ERISIiNG AB 12S
EXISTING AB-12SL
GROUND GROUND
SURFACE SURFACE
10 BGS - ; 1' 10 BGS
20 BGS 20 BGS
30 BGS - 30 BGS
r-1
40 BGS 40 BGS
50 BGS - : '. _ •'. 's • ...; 50 BGS
— 1.;1 I-.rawslf��r+EI!l!I;I.I;
60 BGS - gacic = - 60 BGS
tioo �o0 300
1
1
1
1
1
1
1
1
1
1
1
I
I
I
I
I
I
/
/
/
/
A.
�� •�� � � � � ': \ice \\\ r � ,�
AB-10S
AB-10SL
DISCHARGE LINE I \\\
I
AB-12 OWAU I AB-12D AB-12S
I AB-12BR
- - AB-12SL
' n AB-12 OWAM(30)
AB-12 OWAM
I It frr Jar \\ \\
r
1 I
r GRAPHIC SCALE
DUKE 50 0 100 FIGURE 3
IN FEET
EPROPOSED LOCATIONS FOR
''r ' ENERGY GRRIVER STREET, ENVILSUITE
E,SOUTHSCARO INA29601 AB-12 WELL CLUSTER
I
/ r� PHONE [phone]
/ - CAROLINAS WWWsynterracorp.com PUMPING TEST
/f ���• S ���� MARSHALLSTEAMSTATION PROECTMANAGER:BRANWILKER DATE,02/19/18 MARSHALL STEAM STATION
/ 8320 NC HIGHWAY 150 E LAYOUT: AB-12 Cluster
f TERRELL, NORTH CAROLINA
Oa1ii/�18 d'ii P}d P:�d�kC ErMr C�rWIfNf 1R MM1RSHµL GAP If n1r 2017'r44u4fvr KdtWwr. felt kjMC.01E NIAA91L .V LL--1— Lrfr.,
J

CONCEPTUAL LAYOUT, ACTUAL LOCATIONS FOR
WELLS HAVE NOT BEEN SURVEYED
LEGEND
0
PROPOSED OBSERVATION WELL (UPPER ASH PORE WATER)
PROPOSED OBSERVATION WELL (MEDIUM ASH PORE WATER)
!
PROPOSED OBSERVATION WELL (LOWER ASH PORE WATER)
O
PROPOSED OBSERVATION WELL (SAPROLITE)
0
PROPOSED PUMPING WELL (ASH PORE WATER)
O
PROPOSED PUMPING WELL(SAPROLITE)
AB-15BR
WELL IN BEDROCK
t9 AB-15SL
WELL IN ASH PORE WATER
t9 'AB-15D
WELL IN TRANSITION ZONE
fa CCR-15S
WELL IN SAPROLITE
AQUIFER TEST DISCHARGE LINE AND DIRECTION OF FLOW
ASH BASIN WASTE BOUNDARY (APPROXIMATE)
BGS
BELOW GROUND SURFACE
/v"wL
vit
•� _'' TEMPORARY STORAGE TANKS 1
r (FRACTANKS) \\ \\ fr
* qw.-
1 I I
A.
/ I /
DISCHARGE LINE
CONCEPTUAL PROPOSED PUMPING TEST �� ,/flow F ; . " \\ \\
WELL SCHEMATIC
F ,
�� ' `. tk ��' \ \
AB OWALI� AB-1.5 OWAU � s � � � ;� �: � �
EXISTING AB-15S f� r�� ,+, '� f# �' r r • y \\ \
EXISTING A8-15SL • � V r• \
GROUND , GROPND i w \
SURFACE * . - r -; - SUR ACE ' •• ,•.,. _
10BGS - s 10BGS AB-15BR
20 BGS = •.: �, - 20 BGS tk
.,r . .
30BGS - - 30BGS1�..+Ara
• ,�:, i F. R' fir,. -- r, �r ,� � �`y '� r 3
40 BGS 40 BGS e�
50 BGS SRQROLRE 50 BGS
60 BGS Ii.ITroH.Z[7HE 11111l"I�I�fi - 60 BGS \ // i ,;;^� •. ; �` y{''
6
\ 1 _ ;<
.`-fir-� • ( ,f
1
16
� GRAPHIC SCALE
!�4 '\ DUKE 50 0 100 FIGURE 4
■ \\ IN FEET PROPOSED LOCATIONS FOR
f ' ' �'' - .S r• 7. l \\ GRE RIVER STREET,
CARD INA29601 AB-15 WELL CLUSTER
ENERGY PHONE [phone]
ti�7 \ CAROLINAS www.synterracorpcom PUMPING TEST
MARSHALL STEAM STATION
x MARSHALL STEAM STATION DRAWN BY: CHRIS BRUCE DATE: 02/19/18
�y� w Tero PROJECT MANAGER:BRIAN WILKER
r.11 8320 NC HIGHWAY 150 E LAYOUT: AB-15 Cluster
TERRELL, NORTH CAROLINA
• � 'I r ' __ ng�11+7ntK ;•J! PM %Duko Enn Gm4ru�s\18. R5,{R SIL4L111'.SP SIIninlc 21116\ uIlur i¢siV]WG'.OF MNK1{NL ia��L•e�ws. l.i k,'

CONCEPTUAL LAYOUT, ACTUAL LOCATIONS FOR
WELLS HAVE
NOT BEEN SURVEYED
LEGEND
®
PROPOSED OBSERVATION WELL (UPPER ASH PORE WATER)
4)
PROPOSED OBSERVATION WELL (MEDIUM ASH PORE WATER)
i
PROPOSED OBSERVATION WELL (LOWER ASH PORE WATER)
O
PROPOSED OBSERVATION WELL (SAPROLITE)
PROPOSED PUMPING WELL (ASH PORE WATER)
PROPOSED PUMPING WELL (SAPROLITE)
AB-15BR
WELL IN BEDROCK
AB;SSL
WELL IN ASH PORE WATER
AB-15D
WELL IN TRANSITION ZONE
{� CCR-15S
WELL IN SAPROLITE
AQUIFER TEST DISCHARGE LINE AND DIRECTION OF FLOW
ASH BASIN WASTE BOUNDARY (APPROXIMATE)
BGS
BELOW GROUND SURFACE
CONCEPTUAL PROPOSED PUMPING TEST
WELL SCHEMATIC
AB-18
AB-18 ow.
EMSTIING AEi-iSS I
AB-18 PWS
AB-18 DU GROUND
I1RFA = + SURFACE
_ r _
10 BGS — ;i T 10 BGS
20 BGS — ` ASH ' 20 BGS
30 BGS — . - 30 BGS
40 BGS SAPROLITE 40 BGS
50 BGS 50 BGS
f1 FTRA"NS"TIim esrnTm { }�
60 BGS III TRANSITION ZONE Vllllllljllllllll II — 60 BGS
ADO ��0 3�0
A TOTAL OF TWO PUMPING TEST WILL BE CONDUCTED AT THIS LOCATION.
ONE WILL BE IN THE ASH AND A SECOND WILL BE IN THE UNDERLYING
SAPROLITE.
I /
I /
I I
• { I I
- I /
I /
L
�
I
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1
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!
e
1
• F. � 1
• r ►► 1
1 �
/DUKE
VIP ENERGY
TerraCAROLINAS
MARSHALL STEAM STATION
8320 NC HIGHWAY 150 E
TERRELL, NORTH CAROLINA
ICI
Al
iELINE
GRAPHIC SCALE
50 0 100
IN FEET
148 RIVER STREET, SUITE 220
GREENVILLE, SOUTH CAROLINA 29601
PHONE [phone]
www.symerfacorp.com
DRAWN BY: CHRIS BRUCE DATE: 02/09/18
PROJECT MANAGER:BRIAN WILKER
LAYOUT: Figure 1
0512217OI82.4y PM r_TpuWc-Enggr Cara�nns�Ul 7TA
I /
1 �
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y
/
r
r
I
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I
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I
1
1
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I
r
,
!
r
\
1
FIGURE 5
PROPOSED LOCATIONS FOR
AB-18 WELL CLUSTER
PUMPING TESTS
MARSHALL STEAM STATION

FLOW METER CONFIGURATION
THIS SHOWS THE GENERAL CONFI GURATION OF THE DISCHARGE LINE AND FlLOW METER.
FLOW METER TYPE MAY VERY BUT SHOULD =oLLOW THIS GENERAL CONFIGUJRATION.
"' synTerra
148 RIVER STREET. SUITE 220 GREENVILLc, SOUTH CAROLIN/\ 29601
PHONE [phone]
www.synt.eracorp.com
DRAWN BY·CHRIS BRUCE DATE; 04/01/18
PROJECT MANAGER: BRIAN WILKER
LAYOUT: Flgul"8 3
FIGURE 6 TYPICAL FLOW METER CONFIGURATION MARSHALL STEAM STATIONDUKE ENERGY CAROLINAS, LLCTERRELL, NORTH CAROLINA
SOURCE:
25
20
£ 15
C: :-0 -0
10
s
0
0
' .
STEP DRAWDOWN TEST
•••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••• .......... , ........................ .
t t t
"STEP" PORTION OF CURVE-----····-············ ···············�·-·············· .•........ � ......•......•.....•.....
RECOVERY PORTION OF CURVE
"FLAT" PORTION OF CURVE
............. "' ........... :• ......... .·····t .................................... �-··············· .............. �·························
••...•...•.... . •
• • t ......................................................... �················ ··········�························· • • •
5 10 15
Time [h]
"'
20
148 RIVER STREET. SUITE 220 GREENVILLc, SOUTH CAROLIN/\ 29601
PHONE [phone]
www.synt.eracorp.com
MLU (Multi-Layer Unsteady state)
http://www.microfem.1tl/products/mlu.html synTerra DRAWN BY: CHRIS BRUCE
PROJECT MANAGER: BRIAN WILKER
LAYOl/T: Figure 4
CATE; 04/0'\,1 18
or;: 04/2018 1:29 PM � Duke E:ner
25
•
■
•
■
•
Pumping Period 1, Layer: 1
Pumping Period 2, Layer: 1
Pumping Period 3, Layer: 1
Pumping Period 4, Layer: 1
Pumping Period 5, Layer: 1
Pumping Period 6, Layer:
Pumping Period 7, Layer:
Pumping Period 1
Pumping Period 1
Pumping Period 1
Pumping Period 1
Pumping Period 1
Pumping Period 1
Recovery Period
FIGURE 7 TYPICAL STEP TEST DRAWDOWN CURVE MARSHALL STEAM STATIONDUKE ENERGY CAROLINAS, LLC TERRELL, NORTH CAROLINA
Pumping Test Work Plan Revision 1 May 2018
Duke Energy Carolinas, LLC, Marshall Steam Station SynTerra

TABLES
TABLE 1
WELL CONSTRUCTION DETAILS
FOR PUMPING TESTS
MARSHALL STEAM STATION
DUKE ENERGY CAROLINAS, LLC, TERRELL, NC
P:\Duke Energy Carolinas\18. MARSHALL\08.CCP Ash Basin Pumping Test\Work Plan\Tables\Table 1 Well Construction MODIFIED- Marshall Ash Basin Pumping Tests.xlsx Page 1 of 1
Identification Well Purpose
Approximate
Distance from
Pumping Well
(Feet)
Monitoring
Zone
Base of Ash
(Feet bgs)
Borehole
Diameter
(Inches)
Well
Diameter
(Inches)
Total Well Depth1
(Feet BGS)
Screen
Length
(Feet)
Top of Filter
Sand Pack
(Feet BGS)
Top of
Bentonite Seal
(Feet BGS)
AB-12 LOCATION
AB-12S (Existing)Observation 30 Upper Ash 49 NA 2 13 10 2 1
AB-12SL (Existing)Observation 30 Lower Ash 49 NA 2 50 10 38 36
AB-12D (Existing)Observation 30 Transition Zone 49 NA 2 73.69 5 60 58
AB-12BR (Existing)Observation 30 Bedrock 49 NA 2 105.50 5 98.5 62
AB-12 PWA Pumping NA Lower Ash 45 13
10 6 45 10 32 29
AB-12 OWAU Observation 15 Upper Ash 45 6 2 15 5 8 5
AB-12 OWAM Observation 15 Medium Ash 45 6 2 28 5 21 18
AB-12 OWAL Observation 15 Lower Ash 45 6 2 50 5 42.6 39.6
AB-12 OWAM(30)Observation 30 Medium Ash 49 6 2 27.5 5 20 18
AB-15S (Existing)Observation 30 Upper Ash 46 NA 2 20 10 37 35
AB-15SL (Existing)Observation 30 Lower Ash 46 NA 2 50 10 3 2
AB-15D (Existing)Observation 30 Transition Zone 46 NA 2 77.78 5 62 60
AB-15BR (Existing)Observation 30 Bedrock 46 NA 2 112 5 104 100
AB-15 PWA Pumping NA Lower Ash 50 13
10 6 50 10 37 34
AB-15 OWAU Observation 15 Upper Ash 50 6 2 25 5 17.5 14
AB-15 OWAL Observation 15 Lower Ash 50 6 2 48 5 41 36
AB-18S (Existing)Observation TBD Upper Ash 29.5 NA 2 14 10 2 1
AB-18D (Existing)Observation TBD Transition Zone 29.5 NA 2 77 5 70 68
AB-18 PWA Pumping NA Lower Ash 35 13
10 6 35 10 22 19
AB-18 OWAU Observation 15 Upper Ash 29.5 6 2 13 5 6 4
AB-18 OWAL Observation 15 Lower Ash 29.5 6 2 32.5 5 25 21
AB-18 OWAL(30)Observation 30 Lower Ash 35 6 2 36 5 25 22
AB-18 PWS Pumping NA Saprolite 35 13
10 6 53 10 40 35
AB-18DU Observation 30 Saprolite 34 6 2 53 10 41 38.6
AB-8S (Existing)Observation TBD Upper Ash 22 NA 2 13 10 2 1
AB-8D (Existing)Observation TBD Transition Zone 22 NA 2 100 5 93 91
AB-9S (Existing)Observation TBD Upper Ash NA NA 2 13 10 2 1
AB-9D (Existing)Observation TBD Transition Zone NA NA 2 53 5 46 44
AB-9BR (Existing)Observation TBD Bedrock NA NA 2 83 5 76 72
AB-10S (Existing)Observation TBD Upper Ash 51 NA 2 27.87 15 7 5
AB-10SL (Existing)Observation TBD Lower Ash 51 NA 2 56 10 38 36
AB-10D (Existing)Observation TBD Transition Zone 51 NA 2 76 5 69 66
AB-10BR (Existing)Observation TBD Transition Zone 51 NA 2 125 5 118 102
AB-13S (Existing)Observation TBD Upper Ash 62 NA 2 33.52 15 13 11
AB-13D (Existing)Observation TBD Transition Zone 62 NA 2 86 5 79 77
AB-16S (Existing)Observation TBD Upper Ash 4 NA 2 13.2 10 2.5 1.5
AB-16D (Existing)Observation TBD Transition Zone 4 NA 2 46 5 38 36
Prepared by: CHB Checked by: BDW
Notes:
Total depths and well construction details were determined based on field observations
Bold - Indicates recently installed wells
1 "Total Well Depth" is the depth to the bottom of the screened interval, as measured during well installation.
BGS - Below ground surface
NA - Not applicable
TBD - to be determined
AB-18 LOCATION
AB-15 LOCATION
OBSERVATION WELLS (BEYOND TEST LOCATION)
TABLE 2
SUMMARY OF PUMPING AND OBSERVATION WELLS
MARSHALL STEAM STATION
DUKE ENERGY CAROLINAS, LLC, TERRELL, NC
Step Test Pumping Test Step Test Pumping Test Step Test
(Ash)
Pumping Test
(Ash)
Step Test
(Saprolite)
Pumping Test
(Saprolite)
AB-12S X X 2 Hours
AB-12SL X X 2 Hours
AB-12D X 2 Hours
AB-12BR X 2 Hours
AB-12PWA X X X 2 Hours
AB-12 OWAU X X 2 Hours
AB-12 OWAM X X 2 Hours
AB-12 OWAL X X 2 Hours
AB-12 OWAM(30') X X 2 Hours
AB-15S X X 2 Hours
AB-15SL X X 2 Hours
AB-15D X 2 Hours
AB-15BR X 2 Hours
AB-15 PWA X X X 2 Hours
AB-15 OWAU X X X X 2 Hours
AB-15 OWAL X X X X 2 Hours
AB-18S X X X 2 Hours
AB-18D X X 2 Hours
AB-18 PWA X X X X 2 Hours
AB-18 OWAU X X X 2 Hours
AB-18 OWAL X X X 2 Hours
AB-18 OWAL(30')X X X 2 Hours
AB-18 PWS X X X X 2 Hours
AB-18DU X X X 2 Hours
AB-8S/D X 2 Hours
AB-9S/D/BR X 2 Hours
AB-10S/SL/D/BR X S, SL only 2 Hours
AB-13S/D X X X X S only 2 Hours
AB-16S/D X X X 2 Hours
Notes:Prepared by: CHB Checked by: BDW
Manual Water Levels will be collected during the 72 hour constant rate test only.
Well ID
AB-12 CLUSTER AB-15 CLUSTER AB-18 CLUSTER
Manual Water Level
Readings Frequency
Transducer
Installed
P:\Duke Energy Carolinas\18. MARSHALL\08.CCP Ash Basin Pumping Test\Work Plan\Tables\Table 2 MODTable 2 MOD Page 1 of 1