RBSS Assessment Work Plan_Final_092514

Riverbend Steam Station Ash Basin
Proposed Groundwater
Assessment Work Plan
NPDES Permit NC0004961

September 25, 2014

Duke Energy Carolinas, LLC | Proposed Groundwater Assessment Work Plan
Riverbend Steam Station Ash Basin
TABLE OF CONTENTS

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Table of Contents
Page
Table of Contents ......................................................................................................................... i
Executive Summary .............................................................................................................. ES-1
1.0 Introduction ..................................................................................................................... 1
2.0 Site History ...................................................................................................................... 2
2.1 Plant Description .......................................................................................................... 2
2.2 Ash Basin Description .................................................................................................. 2
2.3 Regulatory Requirements ............................................................................................ 3
3.0 Receptor Information ....................................................................................................... 5
4.0 Regional Geology and Hydrogeology .............................................................................. 6
5.0 Site Geology and Hydrogeology ...................................................................................... 7
6.0 Groundwater Monitoring Results ..................................................................................... 8
7.0 Assessment Work Plan ................................................................................................... 9
7.1 Ash and Soil Sampling Plan ......................................................................................... 9
7.2 Groundwater Sampling Plan .......................................................................................11
7.3 Surface Water Sampling Plan .....................................................................................14
7.4 Site Hydrogeologic Conceptual Model ........................................................................14
7.5 Site-Specific Background Concentrations ...................................................................14
7.6 Groundwater Model ....................................................................................................14
8.0 Proposed Schedule ........................................................................................................16
9.0 References .....................................................................................................................17

Appendix A – Notice of Regulatory Requirements Letter from John E. Skvarla, III, Secretary,
State of North Carolina, To Paul Newton, Duke Energy, dated August 13, 2014.

Duke Energy Carolinas, LLC | Proposed Groundwater Assessment Work Plan
Riverbend Steam Station Ash Basin
TABLE OF CONTENTS

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List of Figures
1. Site Location Map
2. Site Layout Map
3. Proposed Well and Sample Locations

List of Tables
1. Groundwater Monitoring Requirements
2. Monitoring Well Locations
3. Exceedances of 2L Standards June 15, 2011 – June 3, 2014
4. Proposed Additional Exploration and Sampling Plan
5. Soil and Ash Parameters and Analytical Methods
6. Groundwater, Surface Water, and Seep Parameters and Analytical Methods

Duke Energy Carolinas, LLC | Proposed Groundwater Assessment Work Plan
Riverbend Steam Station Ash Basin
EXECUTIVE SUMMARY

ES-1
Executive Summary
Duke Energy Carolinas, LLC (Duke Energy), owns and formerly operated the Riverbend Steam
Station (RBSS), located near Mt. Holly, in Gaston County, North Carolina (see Figure 1). The
coal ash residue from RBSS’s coal combustion process was historically disposed of in the
station’s ash basin located adjacent to the station and Mountain Island Lake. The discharge
from the ash basin is permitted by the North Carolina Department of Environment and Natural
Resources (NCDENR) Division of Water Resources (DWR) under the National Pollutant
Discharge Elimination System (NPDES) Permit NC0004961.
On August 13, 2014, NCDENR issued a Notice of Regulatory Requirements (NORR) letter to
Duke Energy, pursuant to Title 15A North Carolina Administrative Code Chapter (15A NCAC)
02L.0106. The NORR stipulates that for each coal-fueled plant owned, Duke Energy will
conduct a comprehensive site assessment (CSA) that includes a Groundwater Assessment
Work Plan (Work Plan) and a receptor survey. In accordance with the requirements of the
NORR, HDR is in the process of completing a receptor survey to identify all receptors within a
0.5-mile radius (2,640 feet) of the RBSS ash basin compliance boundary. This receptor survey
will also address the requirements of the General Assembly of North Carolina Session 2013
Senate Bill 729 Ratified Bill (SB 729).
Soil and groundwater sampling will be performed to provide information pertaining to the
horizontal and vertical extent of potential soil and groundwater contamination. This will be
performed by sampling existing wells, installing and sampling approximately 26 nested
monitoring well pairs (shallow and deep) and three shallow (only) wells, and collecting soil and
ash samples. In addition, two observation wells will be installed to characterize groundwater
flow in the region between the ash basin and the background monitoring wells. This work will
provide information on the chemical and physical characteristics of site soils and ash, as well as
the geological and hydrogeological features of the site that influence groundwater flow and
direction and transport of constituents from the ash basin and ash storage areas. Samples of
ash basin water will be collected and used to evaluate potential impacts to groundwater and
surface water. In addition, seep samples will be collected from locations identified in May 2014
(as part of Duke Energy’s NPDES permit renewal application) to evaluate potential impacts to
surface water.
The information obtained through implementation of this W ork Plan will be utilized to prepare a
CSA report in accordance with the requirements of the NORR. If it is determined that additional
investigations are required during the review of existing data or data developed from this
assessment, Duke Energy and HDR will notify the NCDENR regional office prior to initiating
additional sampling or investigations.
HDR will also perform an assessment of risks to human health or safety and to the
environment. This assessment will include the preparation of a conceptual site model
illustrating potential pathways from the source to possible receptors.

Duke Energy Carolinas, LLC | Proposed Groundwater Assessment Work Plan
Riverbend Steam Station Ash Basin
INTRODUCTION

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1.0 Introduction
Duke Energy Carolinas, LLC (Duke Energy), owns and formerly operated the Riverbend Steam
Station (RBSS), located near Mt. Holly, in Gaston County, North Carolina (see Figure 1). The
steam station generated electricity by burning coal. The coal ash residue from RBSS’s coal
combustion process was historically disposed of in the station’s ash basin located adjacent to
the station and Mountain Island Lake. The discharge from the ash basin is permitted by the
North Carolina Department of Environment and Natural Resources (NCDENR) Division of Water
Resources (DW R) under the National Pollutant Discharge Elimination System (NPDES) Permit
NC0004961.
On August 13, 2014, NCDENR issued a Notice of Regulatory Requirements (NORR) letter to
Duke Energy, pursuant to Title 15A North Carolina Administrative Code (15A NCAC) Chapter
02L.0106. The NORR stipulates that for each coal-fueled plant owned, Duke Energy will
conduct a comprehensive site assessment (CSA) that includes a Groundwater Assessment
Work Plan (Work Plan) and a receptor survey. In accordance with the requirements of the
NORR, HDR is in the process of completing a receptor survey to identify all receptors within a
0.5-mile radius (2,640 feet) of the RBSS ash basin compliance boundary. The NORR letter is
included as Appendix A.
On behalf of Duke Energy, HDR has prepared this proposed Work Plan for performing the
groundwater assessment as prescribed in the NORR. If it is determined that additional
investigations are required during the review of existing data or data developed from this
assessment, Duke Energy and HDR will notify the NCDENR regional office prior to initiating
additional sampling or investigations.
HDR will also perform an assessment of risks to human health or safety and to the
environment. This assessment will include the preparation of a conceptual site model
illustrating potential pathways from the source to possible receptors.

Duke Energy Carolinas, LLC | Proposed Groundwater Assessment Work Plan
Riverbend Steam Station Ash Basin
SITE HISTORY

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2.0 Site History
2.1 Plant Description
RBSS is a former coal-fired electricity generating facility which had a capacity of 454 megawatts
located in Gaston County, North Carolina, near the town of Mt. Holly. As of April 1, 2013, all of
the coal-fired units have been retired. The site is located between the south bank of the
Catawba River on Mountain Island Lake and the north side of Horseshoe Bend Beach Road.
The surrounding area generally consists of residential properties, undeveloped land, and
Mountain Island Lake. Horseshoe Bend Beach Road runs generally west to east and is located
along a local topographic divide. The topography at the site generally slopes downward from
that divide to Mountain Island Lake.
The seven-unit station began commercial operation in 1929 with two units and then expanded to
seven by 1954. During its final years of operation, RBSS was considered a cycling station and
was brought online to supplement energy supply when electricity demand was at its highest.
2.2 Ash Basin Description
The ash basin system consists of a Primary Cell and a Secondary Cell, separated by an
intermediate dike. The ash basin at RBSS originally consisted of a single-cell basin
commissioned in 1957 and was expanded in 1979. The single basin was divided by
constructing a divider dike to form two separate cells in 1986.
The ash basin is located approximately 2,400 feet to the northeast of the power plant, adjacent
to Mountain Island Lake, as shown on Figure 2. The Primary Cell is impounded by an earthen
embankment dike, referred to as Dam #1 (Primary), located on the west side of the Primary
Cell. The Secondary Cell is impounded by an earthen embankment dike, referred to as Dam #2
(Secondary), located along the northeast side of the Secondary Cell. The toe areas for both
dikes are in close proximity to Mountain Island Lake.
The surface area of the Primary Cell is approximately 41 acres with an approximate maximum
pond elevation of 724 feet. The surface area of the Secondary Cell is approximately 28 acres
with an approximate maximum pond elevation of 714 feet. The full pond elevation of Mountain
Island Lake is approximately 646.8 feet.
The ash basin system was an integral part of the station’s wastewater treatment system which
predominantly received inflows from the ash removal system, station yard drain sump, and
stormwater flows. During station operations, inflows to the ash basin were highly variable due
to the cyclical nature of station operations. The inflows from the ash removal system and the
station yard drain sump are discharged through sluice lines into the Primary Cell. The
discharge from the Primary Cell to the Secondary Cell is through a concrete discharge tower
located near the divider dike.
Although the station is retired, wastewater effluent from other non-ash-related station
discharges to the ash basin is discharged from the Secondary Cell, through a concrete
discharge tower, to Mountain Island Lake. The concrete discharge tower drains through a 30-
Duke Energy Carolinas, LLC | Proposed Groundwater Assessment Work Plan
Riverbend Steam Station Ash Basin
SITE HISTORY

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inch-diameter corrugated metal pipe (CMP) into a concrete-lined channel that discharges to
Mountain Island Lake. The ash basin pond elevation is controlled by the use of concrete stop
logs.
2.3 Regulatory Requirements
The NPDES program regulates wastewater discharges to surface waters to ensure that surface
water quality standards are maintained. RBSS is permitted to discharge wastewater under
NPDES Permit NC0004961, which authorizes discharge of cooling water (Outfall 001), ash
basin discharge (Outfall 002), and yard sump overflow (Outfall 002A) to the Catawba River in
accordance with effluent limitations, monitoring requirements, and other conditions set forth in
the permit.
The NPDES permitting program requires that permits be renewed every five years. The most
recent NPDES permit renewal for RBSS became effective on March 1, 2011, and expires
February 28, 2015.
In addition to surface water monitoring, the NPDES permit requires groundwater monitoring.
Groundwater monitoring has been performed in accordance with the permit conditions
beginning in December 2010. NPDES Permit Condition A (11), Version 1.1, dated June 15,
2011, lists the groundwater monitoring wells to be sampled, the parameters and constituents to
be measured and analyzed, and the requirements for sampling frequency and reporting results.
These requirements are provided in Table 1.
The compliance boundary for groundwater quality at the RBSS ash basin site is defined in
accordance with Title 15A NCAC 02L .0107(a) as being established at either 500 feet from the
waste boundary or at the property boundary, whichever is closer to the waste. The location of
the ash basin compliance monitoring wells, the ash basin waste boundary, and the compliance
boundary are shown on Figure 2.
The locations for the compliance groundwater monitoring wells were approved by the NCDENR
DWR Aquifer Protection Section (APS). All compliance monitoring wells included in Table 1 are
sampled three times per year (in February, June, and October). Analytical results are submitted
to the DWR before the last day of the month following the date of sampling for all compliance
monitoring wells except MW -9, MW-10, and MW -13.
The compliance groundwater monitoring system for the ash basin consists of the following
monitoring wells: MW -7SR, MW -7D, MW -8S, MW-8I, MW-8D, MW-9, MW-10, MW-11SR, MW-
11DR, MW -13, MW -14, MW -15 (shown on Figures 2 and 3). All the compliance wells were
installed in 2010.
One or more groundwater quality standards (2L Standards) have been exceeded in
groundwater samples collected at monitoring wells MW -7SR, MW -7D, MW-8S, MW -8I, MW -8D,
MW -9, MW -10, MW -11SR, MW -11DR, MW -13, MW-14, and MW -15. Exceedances have
occurred for pH, iron, and manganese. Note an exceedance of the interim maximum allowable
concentration (IMAC) groundwater quality standard for antimony has been measured at MW -
7D. Table 3 presents exceedances measured from December 2010 through June 2014.
Duke Energy Carolinas, LLC | Proposed Groundwater Assessment Work Plan
Riverbend Steam Station Ash Basin
SITE HISTORY

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Monitoring wells MW -9, MW -10, and MW-13 are located inside of the compliance boundary as it
was not possible to access the compliance boundary at these three locations. Therefore, these
monitoring wells are installed inside of the 500-foot compliance boundary. These monitoring
wells are also sampled three times per year, and compliance with 2L Standards is determined
by using predictive calculations or a groundwater model to demonstrate compliance. For these
three monitoring wells, Duke Energy previously used a groundwater model to predict the
concentrations at the compliance boundary.
Monitoring wells MW -7SR and MW -7D are considered to represent background water quality.
Monitoring wells MW -8S, MW -8I, and MW-8D are located to the south of an ash storage area
and to the north of Horseshoe Bend Beach Road. Monitoring well MW -9 is located to the north
of a cinder storage area. MW -10 is located downgradient of the Primary Cell. Monitoring wells
MW -11SR and MW -11DR are located northwest of the dike dividing the Primary Cell and the
Secondary Cell. Monitoring wells MW -13, MW-14, and MW -15 are located downgradient of the
Secondary Cell.
With the exception of monitoring wells MW -9, MW-10, and MW-13, the ash basin compliance
monitoring wells were installed at or near the compliance boundary.
Note that monitoring wells MW -1S, MW-1D, MW -2S, MW-2D, MW-3S, MW-3D, MW -4S, MW-
4D, MW -5S, MW -5D, MW -6S, and MW -6D were installed by Duke Energy in 2006 as part of a
voluntary monitoring system. Samples are currently being collected from monitoring wells
MW -4S, MW -4D, MW -5S, and MW -5D as part of groundwater assessment efforts. No samples
are currently being collected from the other voluntary wells. The voluntary wells are shown on
Figure 3.

Duke Energy Carolinas, LLC | Proposed Groundwater Assessment Work Plan
Riverbend Steam Station Ash Basin
RECEPTOR INFORMATION

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3.0 Receptor Information
The August 13, 2014, NORR states:
No later than October 14th, 2014 as authorized pursuant to 15A NCAC 02L
.0106(g), the DWR is requesting that Duke perform a receptor survey at each of
the subject facilities and submitted to the DWR. The receptor survey is required
by 15A NCAC 02L .0106(g) and shall include identification of all receptors within
a radius of 2,640 feet (one-half mile) from the established compliance boundary
identified in the respective National Pollutant Discharge Elimination System
(NPDES) permits. Receptors shall include, but shall not be limited to, public and
private water supply wells (including irrigation wells and unused or abandoned
wells) and surface water features within one-half mile of the facility compliance
boundary. For those facilities for which Duke has already submitted a receptor
survey, please update your submittals to ensure they meet the requirements
stated in this letter and referenced attachments and submit them with the others.
If they do not meet these requirements, you must modify and resubmit the plans.
The results of the receptor survey shall be presented on a sufficiently scaled
map. The map shall show the coal ash facility location, the facility property
boundary, the waste and compliance boundaries, and all monitoring wells listed
in the respective NPDES permits. Any identified water supply wells shall be
located on the map and shall have the well owner's name and location address
listed on a separate table that can be matched to its location on the map.
In accordance with the requirements of the NORR, HDR is in the process of completing a
receptor survey for RBSS to identify all receptors within a 0.5-mile radius (2,640 feet) of the ash
basin compliance boundary to be submitted to NCDENR no later than October 1, 2014. This
receptor survey will also address the requirements of the General Assembly of North Carolina
Session 2013 Senate Bill 729 Ratified Bill (SB 729). The receptors include, but are not limited
to, public and private water supply wells (including irrigation wells and unused or abandoned
wells) and surface water features within a 0.5-mile radius of the RBSS ash basin compliance
boundary. The compliance boundary for groundwater quality, in relation to the ash basin, is
defined in accordance with Title 15A NCAC 02L .0107(a) as being established at either 500 feet
from the waste boundary or at the property boundary, whichever is closer to the source.
The receptor survey will include a map showing the coal ash facility location, the facility property
boundary, the waste and compliance boundaries, and all monitoring wells listed in the NPDES
permit. The identified water supply wells will be located on the map and the well owner's name
and location address listed on a separate table that can be matched to its location on the map.
During completion of the CSA, HDR will update the receptor information as necessary, in
general accordance with the CSA receptor survey requirements. If necessary, an updated
receptor survey will be submitted with the CSA report.
Duke Energy Carolinas, LLC | Proposed Groundwater Assessment Work Plan
Riverbend Steam Station Ash Basin
REGIONAL GEOLOGY AND HYDROGEOLOGY

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4.0 Regional Geology and Hydrogeology
North Carolina is divided into distinct regions by portions of three physiographic provinces: the
Atlantic Coastal Plain, Piedmont, and Blue Ridge (Fenneman, 1938). RBSS is located in the
Charlotte terrane within the Piedmont province. The Piedmont province is bounded to the east
and southeast by the Atlantic Coastal Plain and to the west by the escarpment of the Blue Ridge
Mountains, covering a distance of 150 to 225 miles (LeGrand, 2004). Piedmont bedrock
primarily consists of igneous and metamorphic bedrock. The fractured bedrock is overlain by a
mantle of unconsolidated material known as regolith. The regolith includes, where present, the
soil zone, a zone of weathered, decomposed bedrock known as saprolite, and where present,
alluvium. Saprolite, the product of chemical and mechanical weathering of the underlying
bedrock, is typically composed of clay and coarser granular material up to boulder size and may
reflect the texture of the rock from which it was formed. The weathering product of granitic
rocks may be quartz-rich and sandy-textured, whereas rocks poor in quartz and rich in feldspar
and other soluble minerals form a more clayey saprolite. The regolith serves as the principal
storage reservoir for the underlying bedrock (LeGrand 2004).
A transition zone may occur at the base of the regolith between the soil-saprolite and the
unweathered bedrock. This transition zone of partially weathered rock is a zone of relatively
high permeability compared to the overlying soil-saprolite and the underlying bedrock (LeGrand
2004).
RBSS is located in the Charlotte terrane of the Carolina Zone (Pippin and others, 2008), or in
the older belt terminology, the Charlotte Belt of the Piedmont physiographic province (Piedmont)
(North Carolina Geological Survey, 1985). The Charlotte terrane is characterized by mostly
felsic to mafic plutonic rocks which intrude a suite of mainly metaigneous rocks and minor
metasedimentary rocks (Pippin and others, 2008).
Based on the location of the site on the Geologic Map of the Charlotte 1º x 2º Quadrangle, North
and South Carolina, the underlying bedrock at the site is composed of metamorphosed quartz
diorite and tonalite (mqd). The mqd unit is described as gray, usually medium- to coarse-
grained, generally foliated rock composed dominantly of plagioclase, quartz biotite, hornblende,
and epidote. Biotite, hornblende, and epidote are commonly associated in clots replacing
original mafic phenocrysts; clots may be smeared out, thus defining foliation (Goldsmith and
others 1988).
Groundwater flow paths in the Piedmont are almost invariably restricted to the zone underlying
the topographic slope extending from a topographic divide to an adjacent stream. LeGrand
describes this as the local slope aquifer system. Under natural conditions, the general direction
of groundwater flow can be approximated from the surface topography (LeGrand 2004).
Groundwater recharge in the Piedmont is derived entirely from infiltration of local precipitation.
Groundwater recharge occurs in areas of higher topography (i.e., hilltops) and groundwater
discharge occurs in lowland areas bordering surface water bodies, marshes, and floodplains
(LeGrand 2004).
Duke Energy Carolinas, LLC | Proposed Groundwater Assessment Work Plan
Riverbend Steam Station Ash Basin
SITE GEOLOGY AND HYDROGEOLOGY

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5.0 Site Geology and Hydrogeology
Based on a review of soil boring and monitoring well installation logs provided by Duke Energy,
subsurface stratigraphy consists of the following material types: fill, ash, alluvium, residuum,
saprolite, partially weathered rock (PWR), and bedrock. In general, residuum, saprolite and
PWR were encountered on most areas of the site. Alluvium was encountered in borings
advanced along the northeastern extent of the Secondary Cell, within close proximity to
Mountain Island Lake. Bedrock was encountered sporadically across the site ranging in depth
from 34 feet on the northern extent of the site to greater than 200 feet on the southern extent of
the site near Horseshoe Bend Beach Road. The general stratigraphic units, in sequence from
the ground surface down to boring termination, are defined as follows:
 Fill – Fill material generally consisted of re-worked silts and clays that were borrowed
from one area of the site and re-distributed to other areas. Fill was used in the
construction of dikes and presumably as cover for the ash storage area.
 Ash – Although previous exploration activities, for which Duke Energy provided boring
logs, did not evaluate ash management areas of the site, ash is expected to be present
within the ash basins and ash and cinder storage areas.
 Alluvium – Alluvium is unconsolidated soil and sediment that has been eroded and
redeposited by streams and rivers. Alluvium may consist of a variety of materials
ranging from silts and clays to sands and gravels. Alluvium was encountered in three
boring locations at the base of the northern embankment of the Secondary Cell, proximal
to Mountain Island Lake. Alluvium in these borings was described as yellowish red to
reddish yellow silty clay to clayey sand with well rounded quartz pebbles.
 Residuum – Residuum is the in-place weathered soil that consists of white, orange, tan,
brown, gray or black sandy clay to clayey sand. This unit was encountered in various
thicknesses across the site.
 Saprolite – Saprolite is soil developed by in-place weathering of rock similar to the
bedrock that consists of brown, tan, or green silty sand with trace mica. The primary
distinction from residuum is that saprolite typically retains some structure (e.g., mineral
banding) from the parent rock. This unit was found in most areas across the site and
was described as white, orange, red, brown or black crumbly extremely weathered rock
with relict rock structure.
 Partially Weathered Rock (PWR) – PWR occurs between the saprolite and bedrock
and contains saprolite and rock remnants. This unit was described as white to brownish
yellow to greenish gray with quartz and potassium feldspar fragments.
 Bedrock – Bedrock was encountered in three deep borings completed around the
northern extent of the Secondary Cell and the western extent of the Primary Cell. Depth
to top of bedrock ranged from 34 feet to 51 feet below ground surface (bgs). Bedrock
was described as granite, quartzite and gneiss.
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Riverbend Steam Station Ash Basin
GROUNDWATER MONITORING RESULTS

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6.0 Groundwater Monitoring Results
From December 2010 through June 2014, the compliance groundwater monitoring wells at
RBSS have been sampled a total of 12 times. During this period, these monitoring wells were
sampled in:
 December 2010
 February 2011
 June 2011
 October 2011
 February 2012
 June 2012
 October 2012
 February 2013
 June 2013
 October 2013
 February 2014
 June 2014
Note that compliance monitoring wells MW -11DR, MW -11SR, and MW-15 were first sampled in
February 2011. With the exception of iron, manganese, antimony, and pH, the results for all
monitored parameters and constituents were less than the 2L Standards for all sampling events.
Table 3 lists the range of exceedances for iron, manganese, antimony, and pH for the sampling
events listed above.
HDR previously completed an initial groundwater assessment of the 2L Standard exceedances
in the compliance monitoring wells at RBSS through the February 2013 sampling event
(Groundwater Assessment, Duke Energy Carolinas, LLC, Riverbend Steam Station Ash Basin,
NPDES Permit NC0004961, May 31, 2013). The results and recommendations from this
assessment report will be used during the groundwater assessment required by the NORR.

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ASSESSMENT WORK PLAN

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7.0 Assessment Work Plan
Soil and groundwater sampling will be performed to provide information pertaining to the
horizontal and vertical extent of potential soil and groundwater contamination. Based on readily
available site background information and dependent upon accessibility, HDR anticipates
collecting soil and/or ash samples during installation of approximately 26 nested monitoring well
pairs (shallow and deep) and 3 shallow (only) wells. Groundwater samples will be collected
from the proposed monitoring wells. The proposed well locations are listed in Table 4 and
shown on Figure 3. HDR may also resample select existing monitoring wells to supplement
groundwater quality data. In addition, two observation wells will be installed to characterize
groundwater flow in the region between the ash basin and background monitoring wells. This
work will provide additional information on the chemical and physical characteristics of site soils
and ash, as well as the geological and hydrogeological features of the site that influence
groundwater flow and direction and potential transport of constituents from the ash basin and
ash storage areas.
Samples of ash basin water will also be collected and used to evaluate potential impacts to
groundwater and surface water. If conditions allow for representative sampling, water samples
will be collected from seep sample locations (S-1 through S-12) identified in May 2014 (as part
of Duke Energy’s NPDES permit renewal application) to evaluate potential impacts to surface
water.
A summary of the proposed exploration plan, including estimated sample quantities and depths
of soil borings and monitoring wells, is presented in Table 4. If it is determined that additional
investigations are required during the review of existing data or data developed from this
assessment, Duke Energy and HDR will notify the NCDENR regional office prior to initiating
additional sampling or investigations.
7.1 Ash and Soil Sampling Plan
7.1.1 Boring and Sampling Methods
Prior to drilling each boring, all downhole equipment and tools will be cleaned by washing with
high-pressure hot water. A designated remote cleaning area will be established in the field.
Water for cleaning will be obtained from a tap or hydrant (to be designated) at RBSS, or
supplied by the drilling contractor from an off-site source. Cleaning water will not require
collection, treatment, or disposal.
Borings will be advanced using hollow stem auger or roller cone drilling techniques to facilitate
collection of downhole data. Standard Penetration Testing (SPT) (ASTM D 1586) and split-
spoon sampling will be performed at 2.5-foot to 5-foot increments using an 18-inch split-spoon
sampler. The sampler will be decontaminated with a non-phosphate detergent wash between
sampling depths. Ash and soil samples will be collected by the Project Scientist/Engineer.
Duke Energy Carolinas, LLC | Proposed Groundwater Assessment Work Plan
Riverbend Steam Station Ash Basin
ASSESSMENT WORK PLAN

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Borings will be logged by the Project Scientist/Engineer and ash/soil samples will be observed,
visually classified, and photographed in the field for origin, consistency/relative density, color,
and soil type in accordance with the Unified Soil Classification System (ASTM D2487/D2488).
Samples will be identified with a unique boring number and approximate collection depth (e.g.,
AB-1 (20’-25’)). Sample containers will be provided by HDR’s contracted laboratory prior to
commencement of the on-site investigation. Samples will be delivered to the analytical
laboratory in time to extract the samples within their specified hold times (to be provided by the
laboratory). HDR will provide the name, phone number, and email address of the laboratory
project manager to facilitate sample analysis coordination. Laboratory constituents and
methods for analysis of environmental ash and soil samples are presented in Table 5.
Boring locations will be surveyed for horizontal and vertical control upon completion of the field
exploration program.
7.1.2 Proposed Soil and Ash Sampling Locations and Depths
HDR anticipates collection of soil and ash samples for laboratory analysis at eight locations
within the Primary and Secondary Cells and on the impoundment and divider berms (designated
as AB-1 through AB-8), three locations within the dry ash storage area (designated as AS-2,
AS-4, and AS-6), and two locations within the cinder storage area (designated as C-11 and C-
12). The borings located within the ash basin, dry ash storage area, and cinder storage area
(i.e., within the waste boundary) will extend approximately 20 feet below the ash/native soil
interface, or to auger refusal, whichever is encountered first. In addition, HDR anticipates
collection of soil samples at six background locations (designated as BG-series wells).
Soil samples will not be collected for laboratory analysis during installation of monitoring wells
located outside the waste boundary (designated as GWA-series wells). Proposed boring
locations are shown on Figure 3.
CONSTITUENT SAMPLING AND ANALYSES
In general, ash is expected to be encountered in AB-series, AS-series, and C-series borings.
Ash samples will be collected from shallow and deeper vertical intervals to evaluate variations in
type (e.g., fly ash or bottom ash) and chemical profile of the ash. In general, shallow ash
samples will be collected from the 4-foot to 5-foot intervals and deeper ash samples will be
collected from the 1-foot to 2-foot intervals overlying the ash/native soil interface. The depth of
deeper ash samples is expected to vary based on ash thickness at each specific boring
location. Ash samples will be analyzed by HDR’s subcontract laboratory for total and leachable
inorganic compounds as presented in Table 5.
Soil samples will be collected immediately below the ash/native soil interface and from the
terminus of each boring to characterize soil quality beneath the ash management areas. Soil
samples will be analyzed by HDR’s subcontract laboratory for total inorganics using the same
constituents’ list proposed for the ash samples.
Duke Energy Carolinas, LLC | Proposed Groundwater Assessment Work Plan
Riverbend Steam Station Ash Basin
ASSESSMENT WORK PLAN

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INDEX PROPERTY SAMPLING AND ANALYSES
Physical characteristics of ash and soil will be tested both in the field and in the laboratory to
provide data for use in groundwater modeling. The location and depth of the index property
samples will be based on site-specific geology and decided upon in the field. Based on HDR’s
current understanding of site-specific geology, five hydrostratigraphic units are present on-site.
In general, a minimum of five in-situ permeability tests, either falling or constant head tests, will
be performed in each of the hydrostratigraphic units. In addition, a minimum of five packer tests
will be performed in bedrock.
Laboratory testing of soil and ash collected from SPT samples will include tests for grain size
(with hydrometer), specific gravity, and porosity (calculation).
7.2 Groundwater Sampling Plan
Groundwater samples will be collected from the proposed wells shown on Figure 3.
Groundwater quality data may be supplemented through evaluation of historical data or re-
sampling of select existing monitoring wells. The purpose and anticipated construction details
of the proposed monitoring wells are as follows:
 AB-series Wells – One shallow well screened across the water table (15-foot well
screen) and one deep well with screen installed in the transition zone (5-foot well screen
in weathered rock below auger refusal) will be installed at each location. The AB-series
well locations were selected to provide water quality data in and beneath the ash basin.
 AS-series Wells – One shallow well screened across the water table (15-foot well
screen) and one deep well with screen installed in the transition zone (5-foot well screen
in weathered rock below auger refusal) will be installed at each location. The AS-series
well locations were selected to provide water quality data in and beneath the dry ash
storage area.
 C-series Wells – One shallow well screened across the water table (15-foot well screen)
and one deep well with screen installed in the transition zone (5-foot well screen in
weathered rock below auger refusal) will be installed at each location. The C-series well
locations were selected to provide water quality data in and beneath the cinder storage
area.
 GWA-series Wells – One shallow well screened across the water table (15-foot well
screen) and one deep well with screen installed in the transition zone (5-foot well screen
in weathered rock below auger refusal) will be installed at each location. The GWA-
series well locations were selected to provide water quality data beyond the waste
boundary for use in groundwater modeling (i.e., to evaluate the horizontal and vertical
extent of potentially impacted groundwater around the waste boundary).
 OB-series wells – The observation wells (OB-1 and OB-2) will be installed with 20-foot
screens (across the water table) and will be used for measuring water levels only (no
water quality samples). The OB’s will be installed between the ash basin and the current
site background monitoring well pair MW -7SR/D. The purpose of these OB’s is to
characterize groundwater flow in the region between the ash basin and the background
monitoring wells MW -7SR/D. In addition, monitoring well GWA-7S will be utilized as an
Duke Energy Carolinas, LLC | Proposed Groundwater Assessment Work Plan
Riverbend Steam Station Ash Basin
ASSESSMENT WORK PLAN

12
observation well in conjunction with OB-1 and OB-2 in order to characterize groundwater
flow. Note that monitoring well GWA-7S will be installed to replace the proposed
observation well OB-3, which was included in Duke Energy’s NPDES permit renewal
application dated May 15, 2014.
 BG-series wells – Three nested well pairs (shallow and deep) and three shallow wells
will be installed as described below.
 BG-25S/D – One shallow well screened across the water table (15-foot well screen) and
one deep well with screen installed in the transition zone (5-foot well screen in partially
weathered rock below auger refusal). This location was selected to approximate the
conditions of MW -13 (well screened in region with similar hydrogeologic conditions-
close to river/lake) with respect to redox conditions and will be used to evaluate the
groundwater exceedances measured in MW -13. This location will also provide
additional physical separation from possible influence of the ash basin on groundwater.
 BG-51S/D – One shallow well screened across the water table (15- to 20-foot well
screen) and one deep well with screen installed in the transition zone (5-foot well screen
in partially weathered rock below auger refusal). This location was selected to provide
additional physical separation from possible influence of the ash basin on groundwater.
The well pair will be located approximately mid-way between proposed background well
pair location, BG-25S/D, and proposed background well pair location, BG-21S/D. These
wells will also be useful in the statistical analysis to determine the site-specific
background water quality concentrations (SSBCs) and in characterizing shallow and
deep groundwater flow in the region between the BG-25 S/D and BG-21S/D background
well pairs.
 BG-21S/D – One shallow well screened across the water table (15-foot to 20-foot well
screen) and one deep well with screen installed in the transition zone (5-foot well screen
in partially weathered rock below auger refusal). This location was selected to provide
additional physical separation from possible influence of the ash basin on groundwater.
This well pair will be located approximately 1,600 feet southeast of the ash basin and
east of the existing background well pair location, MW-7SR/D. These wells will also be
useful in the statistical analysis to determine the SSBCs.
 BG-55S, -81S, and -85S – Three shallow wells screened across the water table (15-foot
to 20-foot well screens). These locations were selected to facilitate evaluation of local
groundwater flow conditions in the vicinity of MW -8. More specifically, data obtained
from these wells will be used to evaluate potential hydraulic mounding from the ash
basins.

7.2.1 Well Installation and Development
SHALLOW MONITORING WELLS
At each monitoring well location specified on Figure 3 with an “S” qualifier in the well name (e.g.,
MW -5S), a shallow well will be constructed with a 2-inch-diameter, schedule 40 PVC screen and
casing. Each of these wells will have a 15-foot well screen (0.010-slot) set to bracket the water
table at the time of installation.
Duke Energy Carolinas, LLC | Proposed Groundwater Assessment Work Plan
Riverbend Steam Station Ash Basin
ASSESSMENT WORK PLAN

13
DEEP MONITORING WELLS
At each monitoring well location specified on Figure 3 with a “D” qualifier in the well name (e.g.,
MW -5D), a double-cased deep well will be constructed with a 6-inch-diameter PVC outer casing
and a 2-inch-diameter PVC inner casing and well screen. The purpose of installing cased wells
at the site is to restrict vertical mixing within the shallow and deeper portions of the unconfined
aquifer during well installation. Outer well casings (6-inch casing) will be advanced to auger
refusal and set approximately 1 foot into partially weathered rock (PWR). Note that location-
specific subsurface geology will dictate actual casing depths on a per-well basis. Air rotary
drilling will be used to advance the borehole a minimum of 10 feet into PWR or bedrock with the
intent of setting a 5-foot well screen at least 10 feet below the bottom of the outer casing.
All newly installed monitoring wells will be developed using appropriate measures (e.g.,
agitation, surging, pumping, etc.). Water quality parameters (specific conductance, pH,
temperature and turbidity) will be measured and recorded during development and should
stabilize before development is considered complete. Development will continue until
development water is visually clear (target < 50 Nephelometric Turbidity Units (NTU) Turbidity)
and sediment free. Following development, sounding the bottom of the well with a water level
meter should indicate a “hard” (sediment free) bottom. Development records will be prepared
under the direction of the Project Scientist/Engineer and will include development method(s),
water volume removed, and field measurements of temperature, pH, conductivity, and turbidity.
7.2.2 Hydrogeologic Evaluation
Hydraulic conductivity (slug) tests will be completed in select monitoring wells under the
direction of the Project Scientist/Engineer. Slug tests will be performed to meet the
requirements of the NCDENR Memorandum titled, “Performance and Analysis of Aquifer Slug
Tests and Pumping Tests Policy,” dated May 31, 2007. Water level change during the slug
tests will be recorded by a data logger.
In addition, approximately 5 to 10 packer tests will be conducted during installation of the Type
III wells to facilitate permeability testing of the upper five feet of rock.
7.2.3 Groundwater Sampling
Subsequent to monitoring well installation and development, each newly installed well will be
sampled using low-flow sampling techniques. During low-flow purging and sampling,
groundwater is pumped into a flow-through chamber at flow rates that minimize or stabilize
water level drawdown within the well. Indicator parameters are measured over time (usually at
5-minute intervals). When parameters have stabilized within ±0.2 pH units and ±10 percent for
temperature, conductivity, and dissolved oxygen (DO), and ±10 millivolts (mV) for oxidation
reduction potential (ORP) over three consecutive readings, representative groundwater has
been achieved for sampling. Turbidity levels of 10 NTU or less will be targeted prior to sample
collection. Groundwater samples will be analyzed by a North Carolina certified laboratory for
the constituents included in Table 6. Select constituents may be analyzed for total and
dissolved concentrations.
Duke Energy Carolinas, LLC | Proposed Groundwater Assessment Work Plan
Riverbend Steam Station Ash Basin
ASSESSMENT WORK PLAN

14
7.3 Surface Water Sampling Plan
7.3.1 Ash Basin Surface Water Samples
Surface water samples will be collected from the ash basin at one open water location near the
discharge tower. Samples will be collected approximately 3 feet below the surface and at a
depth of approximately 15 feet. Ash basin surface water samples will be analyzed for the same
constituents as groundwater samples (Table 6). Select constituents may be analyzed for total
and dissolved concentrations.
7.3.2 Seep Samples
Water samples will be collected from the seep sample locations shown on Figure 3. The seep
samples will be collected for laboratory analysis of the constituents listed in Table 6. Select
constituents may be analyzed for total and dissolved concentrations. Duke Energy collects
surface water samples from Mountain Island Lake from upstream and downstream locations for
existing RBSS NPDES permit requirements. If seep analytical results indicate potential for
impacts to Mountain Island Lake, then surface water quality data collected in Mountain Island
Lake will be reviewed.
7.4 Site Hydrogeologic Conceptual Model
The data obtained during the proposed assessment will be supplemented by available reports
and data on site geotechnical, geologic, and hydrologic conditions to develop a site
hydrogeologic conceptual model (SCM). The NCDENR document, “Hydrogeologic Investigation
and Reporting Policy Memorandum,” dated May 31, 2007 (Reference 6), will be used as general
guidance. In general, the SCM will utilize site information to characterize the geologic and
hydrogeologic characteristics of the area of interest, and, where appropriate, lead directly to the
proper construction of a groundwater flow and transport model.
7.5 Site-Specific Background Concentrations
Statistical analysis will be performed to determine the SSBCs to assess whether or not the
exceedances can be attributed to naturally occurring background concentrations or attributed to
potential contamination. Specifically, the relationship between exceedances and turbidity will be
explored to determine whether or not there is a possible correlation due to naturally occurring
conditions and/or well construction.
7.6 Groundwater Model
Groundwater flow and chemical constituent fate and transport at the site will be modeled in
three dimensions using the MODFLOW -2005 groundwater flow numeric engine and the MT3D
transport model with linear isotherm sorption to predict chemical constituent concentrations over
time at the compliance boundary.
The groundwater model layers will be developed based on hydrogeologic properties and other
data obtained during the site investigation and the site hydrogeologic conceptual model. The
model will include the effects of recharge from precipitation.
Duke Energy Carolinas, LLC | Proposed Groundwater Assessment Work Plan
Riverbend Steam Station Ash Basin
ASSESSMENT WORK PLAN

15
Site soil samples will be collected and used to develop site-specific distribution coefficient, Kd,
terms using batch methods (“US EPA Batch-type procedures for estimating soil adsorption of
chemicals Technical Resource Document 530/SW-87/006-F”).
The selection of the initial concentrations and the predictions of the concentrations for
constituents with respect to time are to be developed with consideration of the following data:
 Site-specific analytical results from leach tests and from total digestion of ash samples
taken at varying locations and depths within the ash basin and ash storage piles (if
present),
 Analytical results from appropriate groundwater monitoring wells or surface water
sample locations outside of the ash basin,
 Analytical results from monitoring wells installed in the ash basin pore-water (screened
in ash), and
 Published or other data on sequential leaching tests performed on similar ash.
The groundwater modeling will be conducted in general with the requirements of the May 31,
2007, NCDENR Memorandum titled, “Groundwater Modeling Policy.”
The groundwater model and the report on the results of the groundwater modeling will be
prepared by Dr. William Langley, P.E., Department of Civil and Environmental Engineering,
University of North Carolina at Charlotte. Dr. Langley will perform the work under contract with
HDR, and the groundwater model report will be included as an attachment to the CSA. The
groundwater model will be used, as required, to evaluate options for potential corrective action
in the subsequent phase of work.

Duke Energy Carolinas, LLC | Proposed Groundwater Assessment Work Plan
Riverbend Steam Station Ash Basin
PROPOSED SCHEDULE

16
8.0 Proposed Schedule
Duke Energy will submit the CSA Report within 180 days of NCDENR approval of this Work
Plan. The anticipated schedule for implementation of field work, evaluation of data, and
preparation of the Work Plan is presented in the table below.
Activity Start Date Duration to Complete
Field Exploration Program 10 days following Work Plan approval 75 days
Receive Laboratory Data 14 days following end of Exploration Program 15 days
Evaluate Lab/Field Data, Develop SCM 5 days following receipt of Lab Data 30 days
Prepare and Submit CSA 10 days following Work Plan approval 170 days

Duke Energy Carolinas, LLC | Proposed Groundwater Assessment Work Plan
Riverbend Steam Station Ash Basin
REFERENCES

17
9.0 References

1. Fenneman, Nevin Melancthon. “Physiography of eastern United States.” McGraw-Hill.
1938.
2. Goldsmith, R., Milton, D. J. and Horton, J. W., Jr. 1988. Geologic map of the
Charlotte 1o x 2o quadrangle, North Carolina and South Carolina: United States
Geological Survey, Miscellaneous Investigations Series, Map I-1251-E, scale 1:250,000.
3. Groundwater Assessment, Duke Energy Carolinas, LLC, Riverbend Steam Station Ash
Basin, NPDES Permit NC0004961, May 31, 2013.
4. LeGrand, Harry E. 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.
5. NCDENR Memorandum “Performance and Analysis of Aquifer Slug Tests and Pumping
Tests Policy,” May 31, 2007.
6. NCDENR document, “Hydrogeologic Investigation and Reporting Policy Memorandum”,
dated May 31, 2007.
7. North Carolina Geological Survey, 1985, Geologic map of North Carolina: North Carolina
Geological Survey, General Geologic Map, scale 1:500000.
8. Pippin, C.G., Chapman, M.J., Huffman, B.A., Heller, M.J., and Schelgel, M.E., 2008,
Hydrogeologic setting, ground-water flow, and ground-water quality at the Langtree
Peninsula research station, Iredell County, North Carolina, 2000–2005: U.S. Geological
Survey Scientific Investigations Report 2008–5055, 89 p. (available online at
http://pubs.water.usgs.gov/sir2008–5055).
9. US EPA Batch-type procedures for estimating soil adsorption of chemicals
TechnicalResource Document 530/SW -87/006-F.

Figures

DRAFT
- A s a
� t i
LEGEND:
DUKE ENERGY PROPERTY BOUNDARY
_ - ASH BASIN COMPLIANCE BOUNDARY
jy- - ASH BASIN COMPLIANCE BOUNDARY COINCIDENT
_ - - - WITH DUKE ENERGY PROPERTY BOUNDARY
sY'
ASH BASIN WASTE BOUNDARY
ASH OR CINDER STORAGE AREA BOUNDARY
:A ;...— — — — — — — — — — — TOPOGRAPHIC CONTOUR (4 FOOT)
',y�'•'i . ,-�,',� � � � A - � • 0 • J` ASH BASIN COMPLIANCE GROUNDWATER
• a !fe . J MONITORING WELL LOCATION
"� /' c•.p •f•i. ,-�'��' STREAM
' lam• �?' 9y t . - P a
PIN 19
.lf
Is
�z FBI • � ff ` a., �,
'�'�.. f •1 "_'`r�l rtd£7 �•�. ��. y � -' � � �+ ,fir..' a �. f'C -. 1 .'1r,k�c e,�,•��iep'�. � � _ •
�`• � �-I �'. -a fir. s .� c. t �`" r•� 't—,'
r' .� � 7y. ,..f,t - '�• ,,� - - -.S �' � fix
NOTES:
1. PARCEL DATA FOR THE SITE WAS OBTAINED FROM DUKE ENERGY REAL ESTATE AND IS APPROXIMATE. SCALE (FEET) SITE LAYOUT MAP DATE
2. ASH STORAGE BOUNDARY AND CINDER STORAGE BOUNDARY ARE APPROXIMATE. 0 S00' E,99'
3. AS -BUILT MONITORING WELL LOCATIONS PROVIDED BY DUKE ENERGY. /" = 600' ®_ _ DUKE ENERGY CAROLI NAS, LLC 9/25/2014
4. SHALLOW MONITORING WELLS (S) - WELL SCREEN INSTALLED ACROSS THE SURFICIAL WATER TABLE. ® RIVERBEND STEAM STATION FIGURE
5. DEEP MONITORING WELLS (D) - WELL SCREEN INSTALLED IN THE TRANSITION ZONE BETWEEN COMPETENT BEDROCK AND THE REGOLITH.
6. TOPOGRAPHY DATA FOR THE SITE WAS OBTAINED FROM INC DOT GEOGRAPHIC INFORMATION SYSTEM (GIS) WEB SITE. N PD ES PERMIT I\I O. I\I C 0004961
7. ORTHOPHOTOGRAPHY WAS OBTAINED FROM WSP (DATED APRIL 2014). — 2
8. THE COMPLIANCE BOUNDARY IS ESTABLISHED ACCORDING TO THE DEFINITION FOUND IN 15A NCAC 02L.0107 (a). GASTON COUNTY, NORTH CAROLINA

ev—
ASH STORAG
TV v
°.� n
r.. e••
' X
PIN BG-81S
WA-4S/D Al
3G-8SS '44, F/
c-
le
NOTES:
1. PARCEL DATA FOR THE SITE WAS OBTAINED FROM DUKE ENERGY REAL ESTATE AND IS APPROXIMATE. SCALE (FEET)
2. ASH STORAGE BOUNDARY AND CINDER STORAGE BOUNDARY ARE APPROXIMATE. 0 100' 600
3. AS -BUILT MONITORING WELL LOCATIONS PROVIDED BY DUKE ENERGY.
4. SHALLOW MONITORING WELLS (S) - WELL SCREEN INSTALLED ACROSS THE SURFICIAL WATER TABLE. /" = 600'
5. DEEP MONITORING WELLS (D) - WELL SCREEN INSTALLED IN THE TRANSITION ZONE BETWEEN COMPETENT BEDROCK AND THE REGOLITH.
6. TOPOGRAPHY DATA FOR THE SITE WAS OBTAINED FROM NC DOT GEOGRAPHIC INFORMATION SYSTEM (GIS) WEB SITE.
7. ORTHOPHOTOGRAPHY WAS OBTAINED FROM WSP (DATED APRIL 2014).
8. THE COMPLIANCE BOUNDARY IS ESTABLISHED ACCORDING TO THE DEFINITION FOUND IN 15A NCAC 02L.0107 (a).
9. PROPOSED WELL LOCATIONS ARE APPROXIMATE AND MAY BE ADJUSTED DUE TO FIELD CONDITIONS.
10. SEEP SAMPLING LOCATIONS WERE OBTAINED BY HDR USING A TRIMBLE HANDHELD GPS UNIT ON APRIL 29, 2014.
* INDICATES SEEP SAMPLING LOCATIONS WERE NOT RECORDED WITH GPS UNIT AND ARE APPROXIMATE.
r... e...
..:
LEGEND:
�r is
•
DUKE ENERGY PROPERTY BOUNDARY
ASH BASIN COMPLIANCE BOUNDARY
-
ASH BASIN COMPLIANCE BOUNDARY COINCIDENT
WITH DUKE ENERGY PROPERTY BOUNDARY
ASH BASIN WASTE BOUNDARY
ASH OR CINDER STORAGE AREA BOUNDARY
t
- - - . -
TOPOGRAPHIC CONTOUR (4 FOOT)
ASH BASIN COMPLIANCE GROUNDWATER
-
MONITORING WELL LOCATION
ASH BASIN VOLUNTARY GROUNDWATER
MONITORING WELL LOCATION
IRSESHOE
PROPOSED GROUNDWATER MONITORING WELL
REND RAROAD
LOCATION
PROPOSED OBSERVATION WELL LOCATION
•
PROPOSED SURFACE WATER SAMPLE LOCATION
•
SEEP SAMPLE LOCATION
,•'
.���������.
STREAM
PROPOSED WELL AND SAMPLE LOCATIONS DATE
DUKE ENERGY CAROLINAS, LLC
9/25/2014
RIVERBEND STEAM STATION
FIGURE
NPDES PERMIT NO. NC0004961
3
GASTON COUNTY, NORTH CAROLINA

Tables

TABLE 1 – GROUNDWATER MONITORING REQUIREMENTS
Well Nomenclature Constituents and Parameters Frequency
Monitoring Wells: MW-7SR,
MW-7D, MW-8S, MW-8I, MW-
8D, *MW-9, *MW-10, MW-
11SR, MW-11DR, *MW-13,
MW-14, MW-15
Antimony Chromium Nickel Thallium
February,
June,
October
Arsenic Copper Nitrate Water
Level
Barium Iron pH Zinc
Boron Lead Selenium
Cadmium Manganese Sulfate
Chloride Mercury TDS
Note: Monitoring wells marked with * are located inside of the compliance boundary.

TABLE 2 – MONITORING WELL LOCATIONS
Monitoring Well Locations Monitoring Well

At or Near the Compliance
Boundary

MW -7SR, MW -7D, MW -8S,
MW -8I, MW -8D, MW -11SR,
MW -11DR, MW -14, MW -15
Inside of the Compliance
Boundary

MW -9, MW -10, MW -13

TABLE 3 – EXCEEDANCES OF 2L STANDARDS
DECEMBER 2010 – JUNE 2014

Parameter Iron Manganese pH Antimony
Units µg/L µg/L SU µg/L
2L Standard 300 50 6.5 - 8.5 1
Well ID Range of Exceedances
MW-7SR 445 – 790 67 – 413 5.0 – 5.4 No Exceedances
MW-7D No Exceedances No Exceedances 5.5 – 5.8 1.04
MW-8S No Exceedances 68 – 144 4.3 – 5.2 No Exceedances
MW-8I 436 – 976 52 – 290 5.7 – 6.4 No Exceedances
MW-8D 777 – 4,160 82 – 671 6.3– 6.5 No Exceedances
MW-9* 341 – 1,950 62 – 147 5.8 – 6.4 No Exceedances
MW-10* 310 – 1,420 67 – 355 4.8 – 5.4 No Exceedances
MW-11SR 486 59 - 384 5.6 – 6.1 No Exceedances
MW-11DR No Exceedances 51 – 168 5.6 - 5.8 No Exceedances
MW-13* 7,690– 37,700 8,070 – 11,200 5.8 – 6.4 No Exceedances
MW-14 371 – 935 55 – 353 No Exceedances No Exceedances
MW-15 399 52 – 86 5.1 – 5.3 No Exceedances
Note: Monitoring wells marked with * are located inside of the compliance boundary.

TABLE 4 – ENVIRONMENTAL EXPLORATION AND SAMPLING PLAN
Exploration
Area
Soil Borings Shallow Monitoring Wells Deep Monitoring Wells Surface Water
Boring IDs Quantity
Estimated
Boring Depth
(ft bgs)
Well IDs Quantity
Estimated Well
Depth
(ft bgs)
Screen
Length
(ft)
Well IDs Quantity
Estimated
Casing Depth
(ft bgs)
Estimated Well
Depth
(ft bgs)
Screen
Length
(ft)
Quantity of
Locations
Quantity of
Samples
Ash Basin AB-1 through
AB-8 8 75 AB-1S through
AB-8S 8 30-50 15 AB-1D through
AB-8D 8 40-60 55-75 5 2 4
Ash Storage /
Cinder
Storage
AS-2, AS-4,
AS-6, C-11,
and C-12
5 80
AS-2S, AS-4S,
AS-6S, C-11S,
and C-12S
5 30-80 15
AS-2D, AS-4D,
AS-6D, C-11D,
and C-12D
5 40-90 55-105 5 N/A N/A
Beyond
Waste
Boundary
N/A 0 N/A GWA-1S through
GWA-10S 10 15-45 10-15 GWA-1D through
GWA-10D 10 25-125 40-140 5 N/A N/A
Background
BG-21, BG-25,
BG-51, BG-55,
BG-81, BG-85
6 30-100
BG-21S, BG-
25S, BG-51S,
BG-55S, BG-
81S, BG-85S
6 20-60 15 BG-21D, BG-25D,
BG-51D 3 30-125 45-140 5 N/A N/A
Notes:
1. Estimated boring and well depths based on data available at the time of work plan preparation and subject to change based on site-specific conditions in the field. 2. Laboratory analyses of soil, ash, groundwater, and surface water samples will be performed in accordance with the constitu ents and methods identified in Tables 4 and 5. 3. Additionally, soils will be tested in the laboratory to determine grain size (with hydrometer), specific gravity, and permeability. 4. During drilling operations, down hole testing will be conducted to determine in -situ soil properties such as horizontal and vertical hydraulic conductivity. 5. Actual number of field and laboratory tests will be determined in field by Field Engineer or Geologist in accordance with project specifica tions.

TABLE 5 – SOIL AND ASH PARAMETERS AND ANALYTICAL METHODS
INORGANIC COMPOUNDS UNITS METHOD
Antimony mg/kg EPA 6020
Arsenic mg/kg EPA 6020
Barium mg/kg EPA 6010
Boron mg/kg EPA 6010
Cadmium mg/kg EPA 6020
Chloride mg/kg SM4500-Cl-E
Chromium mg/kg EPA 6010
Copper mg/kg EPA 6010
Iron mg/kg EPA 6010
Lead mg/kg EPA 6020
Manganese mg/kg EPA 6010
Mercury mg/kg EPA Method 7470A/7471
Nickel mg/kg EPA 6010
pH SU EPA 9045
Selenium mg/kg EPA 6020
Thallium (low level) mg/kg EPA 6020
Zinc mg/kg EPA 6010
Notes:
1. Soil samples to be analyzed for Total Inorganics using USEPA Methods 6010/6020 and pH using
USEPA Method 9045, as noted above.
2. Ash samples to be analyzed for Total Inorganics using USEPA Methods 6010/6020 and pH using
USEPA Method 9045; select ash samples will also be analyzed for leaching potential using SPLP
Extraction Method 1312 in conjunction with USEPA Methods 6010/6020. SPLP results to be reported
in units of mg/L for comparison to 2L Standards.

TABLE 6 – GROUNDWATER, SURFACE WATER, AND SEEP
PARAMETERS AND ANALYTICAL METHODS
PARAMETER UNITS METHOD
FIELD PARAMETERS
pH SU Field Water Quality Meter
Specific Conductance mmho/cm Field Water Quality Meter
Temperature ºC Field Water Quality Meter
Dissolved Oxygen mg/L Field Water Quality Meter
Oxidation Reduction Potential mV Field Water Quality Meter
NPDES CONSTITUENTS
Antimony µg/L EPA 200.8 or 6020
Arsenic µg/L EPA 200.8 or 6020
Barium µg/L EPA 200.7 or 6010
Boron µg/L EPA 200.7 or 6010
Cadmium µg/L EPA 200.8 or 6020
Chloride mg/L EPA 300.0
Chromium µg/L EPA 200.7 or 6010
Copper mg/L EPA 200.7 or 6010
Iron µg/L EPA 200.7 or 6010
Lead µg/L EPA 200.8 or 6020
Manganese µg/L EPA 200.7 or 6010
Mercury µg/L EPA 245.1
Nickel µg/L EPA 200.7 or 6010
Nitrate as Nitrogen mg-N/L EPA 300.0
Selenium µg/L EPA 200.8 or 6020
Sulfate mg/L EPA 300.0
Thallium (low level) µg/L EPA 200.8 or 6020
Total Dissolved Solids mg/L EPA 160.1 or SM 2540C
Zinc mg/L EPA 200.7 or 6010
ADDITIONAL GROUNDWATER CONSTITUENTS
Alkalinity (as CaCO3) mg/L SM2320B
Calcium mg/L EPA 200.7
Ferrous Iron mg/L SM4500-Fe
Magnesium mg/L EPA 200.7
Potassium mg/L EPA 200.7
Sodium mg/L EPA 200.7
Sulfide mg/L SM4500S-F
Total Organic Carbon mg/L SM5310

Notes:
1. Select constituents may be analyzed for total and dissolved concentrations.

Appendix A
Notice of Regulatory Requirements Letter from
John E. Skvarla, III, Secretary, State of North
Carolina, to Paul Newton, Duke Energy, dated
August 13, 2014.

A 4
A=(WA
4AF1
NCDENR
North Carolina Department of Environment and Natural Resources
Pat McCrory John E. Skvarla, III
Governor Secretary
August 13, 2014
CERTIFIED MAIL 7004 2510 0000 3651 1168
RETURN RECEIPT REQUESTED
Paul Newton
Duke Energy
526 South Church Street
Charlotte, NC 28202
Subject: Notice of Regulatory Requirements
Title 15A North Carolina Administrative Code (NCAC) 02L .0106
14 Coal Ash Facilities in North Carolina
Dear Mr. Newton:
Chapter 143, North Carolina General Statutes, authorizes and directs the Environmental
Management Commission of the Department of Environment and Natural Resources to protect
and preserve the water and air resources of the State. The Division of Water Resources (DWR)
has the delegated authority to enforce adopted pollution control rules.
Rule 15A NCAC 02L .0103(d) states that no person shall conduct or cause to be conducted any
activity which causes the concentration of any substance to exceed that specified in 15A NCAC
02L .0202. As of the date of this letter, exceedances of the groundwater quality standards at 15A
NCAC 02L .0200 Classifications and Water Quality Standards Applicable to the Groundwaters
of North Carolina have been reported at each of the subject coal ash facilities owned and
operated by Duke Energy (herein referred to as Duke).
Groundwater Assessment Plans
No later than September, 26 2014 Duke Energy shall submit to the Division of Water Resources
plans establishing proposed site assessment activities and schedules for the implementation,
completion, and submission of a comprehensive site assessment (CSA) report for each of the
following facilities in accordance with 15A NCAC 02L .0106(g):
Asheville Steam Electric Generating Plant
Belews Creek Steam Station
Buck Steam Station
Cape Fear Steam Electric Generating Plant
Cliffside Steam Station
1636 Mail Service Center, Raleigh, North Carolina 27699-1636
Phone: [phone] Internet: www.ncdenr.gov
An Equal Opportunity 1 Affirmative Action Employer— Made in part by recycled paper

Mr. Paul Newton
August 12, 2014
Page 2 of 3
Dan River Combined Cycle Station
H.F. Lee Steam Electric Plant
Marshall Steam Station
Mayo Steam Electric Generating Plant
Plant Allen Steam Station
Riverbend Steam Station
Roxboro Steam Electric Generating Plant
L.V. Sutton Electric Plant
Weatherspoon Steam Electric Plant
The site assessment plans shall include a description of the activities proposed to be completed
by Duke that are necessary to meet the requirements of 15A NCAC 02L .0106(g) and to provide
information concerning the following:
(1) the source and cause of contamination;
(2) any imminent hazards to public health and safety and actions taken to mitigate
them in accordance to 15A NCAC 02L .0106(f);
(3) all receptors, and significant exposure pathways;
(4) the horizontal and vertical extent of soil and groundwater contamination and all
significant factors affecting contaminant transport; and
(5) geological and hydrogeological features influencing the movement,. chemical, and
physical character of the contaminants.
For your convenience, we have attached guidelines detailing the information necessary for the
preparation of a CSA report. The DWR will review the plans and provide Duke with review
comments, either approving the plans or noting any deficiencies to be corrected, and a date by
which a corrected plan is to be submitted for further review and comment or approval. For those
facilities for which Duke has already submitted groundwater assessment plans, please update
your submittals to ensure they meet the requirements stated in this letter and referenced
attachments and submit them with the others.
Receptor Survey
No later than October 14t', 2104 as authorized pursuant to 15A NCAC 02L .0106(g), the DWR is
requesting that Duke perform a receptor survey at each of the subject facilities and submitted to
the DWR. The receptor survey is required by 15A NCAC 02L .0106(g) and shall include
identification of all receptors within a radius of 2,640 feet (one-half mile) from the established
compliance boundary identified in the respective National Pollutant Discharge Elimination
System (NPDES) permits. Receptors shall include, but shall not be limited to, public and private
water supply wells (including irrigation wells and unused or abandoned wells) and surface water
features within one-half mile of the facility compliance boundary. For those facilities for which
Duke has already submitted a receptor survey, please update your submittals to ensure they meet
the requirements stated in this letter and referenced attachments and submit them with the others.
If they do not meet these requirements, you must modify and resubmit the plans.

Mr. Paul Newton
August 12, 2014
Page 3 of 3
The results of the receptor survey shall be presented on a sufficiently scaled map. The map shall
show the coal ash facility location, the facility property boundary, the waste and compliance
boundaries, and all monitoring wells listed in the respective NPDES permits. Any identified
water supply wells shall be located on the map and shall have the well owner's name and
location address listed on a separate table that can be matched to its location on the map.
Failure to comply with the State's rules in the manner and time specified may result in the
assessment of civil penalties and/or the use of other enforcement mechanisms available to the
State.
We appreciate your attention and prompt response in this matter. If you have any questions,
please feel free to contact S. Jay Zimmerman, Water Quality Regional Operations Section Chief,
at [phone].
2hn
ierely,
E. Skvarla, III
Attachment enclosed
cc: Thomas A. Reeder, Director, Division of Water Resources
Regional Offices — WQROS
File Copy

August 12, 2014
GUIDELINES FOR COMPREHENSIVE SITE ASSESSMENT
This document provides guidelines for those involved in the investigation of
contaminated soil and/or groundwater, where the source of contamination is from:
■ Incidents caused by activities subject to permitting under G.S. 143-215.1
■ Incidents caused by activities subject to permitting under G.S. 87-88
■ Incidents arising from agricultural operations, including application of
agricultural chemicals, but not including unlawful discharges, spills or
disposal of such chemicals
Comprehensive Site Assessment (CSA)
NOTE: Regional Offices may request additional information in support of the CSA to aid
in their review and will not approve the CSA if any of the elements specified below have
not been included or have not been sufficiently addressed
Minimum Elements of the Comprehensive Site Assessment Report:
A. Title Page
• Site name, location and Groundwater Incident number (if
assigned) and Permit Number;
• Date of report;
• Responsible Party and/or permiee, including address and
phone number;
• Current property owner including address and phone
number;
• Consultant/contractor information including address and
phone number;
• Latitude and longitude of the facility; and
• Seal and signature of certifying P.E. or P.G., as appropriate.
B. Executive Summary
The Executive Summary should provide a brief overview of the pertinent
site information (i.e., provide sufficient information to acquaint the reader
with the who, what, when, where, why and how for site activities to date).
1. Source information:
Type of contaminants
2. Initial abatement/emergency response information.
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August 12, 2014
3. Receptor information:
•
Water supply wells;
•
Public water supplies (wells, surface water intakes);
•
Surface water bodies;
•
Wellhead protection areas;
•
Deep aquifers in the Coastal Plain physiographic region;
•
Subsurface structures; and
•
Land use.
4. Sampling/investigation results:
•
Nature and extent of contamination;
•
Maximum contaminant concentrations;
•
Site hydrogeology.
5. Conclusions
and recommendations.
C. Table of Contents
• First page number for each section listed.
• List of figures (all referenced by number and placed in a
single section following contents text).
• List of tables (all referenced by number and placed in a single
section following contents text).
• List of appendices.
D. Site History and Source Characterization
• Provide a history of property ownership and use. Indicate
dates of ownership, uses of the site, and potential sources of
contaminants.
• Discuss the source(s) of contamination, including primary
and secondary sources.
• For permitted activities, describe nature of activity, permitted
waste, application of all instances of
over-application/irrigation of wastes or water
• Summarize assessment activities and corrective actions
performed to date including emergency response, initial
abatement, primary and secondary source removal.
• Discuss geographical setting and present/future surrounding
land uses.
E. Receptor Information
Provide a site map showing labeled well locations within a

August 12, 2014
minimum of 1500 feet of the known extent of contamination.
Key to the table and maps described.
NOTE: As the known extent of contamination changes, the
receptor survey must be updated to reflect the change. This
applies throughout the Receptor Information section.
• In table format, list all water supply wells, public or private,
including irrigation wells and unused wells, (omit those that
have been properly abandoned in accordance with 15A
NCAC 2C .0100) within a minimum of 1500 feet of the known
extent of contamination. Note whether well users are also
served by a municipal water supply.
• For each well, include well number, well owner and user
names, addresses and telephone numbers, use of the well,
well depth, well casing depth, well screen interval, and
distance from source of contamination;
NOTE: It will often be necessary to conduct any or all of the
following in order to ensure reliability in a water supply well
survey.
o Call the city/county water department to inquire about
city water connections,
o Visit door-to-door (make sure that you introduce
yourself and state your purpose to residents prior to
examining their property) to obtain accurate
description of water usage, and if some residents are
not at home, ask surrounding neighbors who are
home about the water usage at those residences.
Even if a public water line is available, some
residents still use their well water and are not
connected to the public water system; and
o Search for water meters and well houses.
• Site map showing location of subsurface structures (e.g.,
sewers, utility lines, conduits, basements, septic tanks,
drain fields, etc.) within a minimum of 1,500 feet of the known
extent of contamination;
• Table of surrounding property owner addresses;
• Discuss the availability of public water supplies within a
minimum of 1,500 feet of the source area, including the
distance and location to the nearest public water lines and
the source(s) of the public water supply;
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August 12, 2014
• Identify all surface water bodies (e.g., ditch, pond, stream,
lake, river) within a minimum of 1,500 feet of the source of
contamination;
• Determine the location of any designated wellhead protection
areas as defined in 42 USC 300h-7(e) within a minimum of
1,500 feet of the source of contamination. Identify and
discuss the location of the water supply well(s) for which the
area was designated a wellhead protection area, and the
extent of the protected area. Include information about the
well owner, well -construction specifications (especially at
screened intervals), pumping rate and pumping schedule.
Information regarding designated wellhead. protection areas
may be obtained by contacting the Public Water Supply
Section at [phone];
• Discuss the uses and activities (involving possible human
exposure to contamination) that could occur at the site and
adjacent properties. Examples of such activities and uses
include but are not limited to use of a property for an office,
manufacturing operation, residence, store, school, gardening
or farming activities, recreational activities, or undeveloped
land;
• Determine whether the contaminated area is located in an
area where there is recharge to an unconfined or
semi -confined deeper aquifer that is being used or may be
used as a source of drinking water. Based on a review of
scientific literature on the regional hydrogeology and well
construction records and lithological logs for deeper wells in
the area, identify and describe the deep aquifers underlying
the source of contamination. Include information on the depth
of the deep aquifer in relation to the surficial saturated zone,
the lithology and hydraulic conductivity of the strata between
the surficial aquifer and the deeper aquifer, and the
difference in groundwater head between the surficial aquifer
and the deeper aquifer. Discuss the local and regional usage
of the deep aquifer and the draw down from major pumping
influences. Also, specify the distance from the source of
contamination to major discharge areas such as streams and
rivers. Cite all sources and references used for this
discussion.
NOTE: This requirement (last bullet) only pertains to
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August 12, 2014
contamination sources in the Coastal Plain physiographic region
as designated on a map entitled "Geology of !North Carolina"
published by the Department in 1985. However,
recharge/discharge, hydraulic conductivity, lithology, head
difference, etc. is also important information at mountains
and piedmont sites.
F. Regional Geology and Hydrogeology
Provide a brief description of the regional geology and hydrogeology. Cite
all references.
G. Site Geology and Hydrogeology
• Describe the soil and geology encountered at the site. Use
the information obtained during assessment activities (e.g.,
lithological descriptions made during drilling, probe surveys,
etc.). This information should correspond to the geologic
cross sections required in N. below; and
• Based on the results of the groundwater investigation,
describe the site hydrogeology, including a discussion of
groundwater flow direction, hydraulic gradient, hydraulic
conductivity and groundwater velocity. Discuss the effects of
the geologic and hydrogeological characteristics on the
migration, retardation, and attenuation of contaminants.
H . Soil Sampling Results
Using figures and tables to the extent possible, describe all soil sampling
performed to date and provide the rationale for sample locations, number
of samples collected, etc. Include the following information:
• Location of soil samples;
• Date of sampling;
• Type of soil samples (from excavation, borehole, Geoprobe,
etc.);
• Soil sample collection procedures (split spoon, grab, hand
auger, etc.)
• Depth of soil samples below land surface;
• Soil sample identification
• Soil sample analyses;
• Soil sample analytical results (list any contaminant detected
above the method detection limit); and
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August 12, 2014
• Identify any sample analytical results that exceed the
applicable cleanup levels.
NOTE: Information related to H. above should correspond to the
sampling location and sampling results maps required in N. below.
I . Groundwater Sampling Results
Using figures and tables to the extent possible describe the groundwater
sampling performed to date and provide the rationale for sample locations
(based on source and contaminant type), number of samples collected,
etc. Include the following information:
• Location of groundwater samples and monitoring wells;
• Date of sampling;
• Groundwater sample collection procedures (bailer, pump,
etc.);
• Groundwater sample identification and whether samples
were collected during initial abatement, CSA, etc.;
• Groundwater sample analyses;
• Groundwater sample analytical results (list any contaminant
detected above the method detection limit; and
• Identify all sample analytical results that exceed 15A NCAC
2L or interim standards.
NOTE: Information related to 1. above should correspond to the
sampling location and sampling results maps required in N. below.
J. Hydrogeological Investigation
Describe the hydrogeological investigation performed including all
methods, procedures and calculations used to characterize site
hydrogeological conditions. The following information should be discussed
and should correspond to the maps and figures required below:
• Groundwater flow direction;
• Hydraulic gradient (horizontal and vertical);
• Hydraulic conductivity;
• Groundwater velocity;
• Contaminant velocity;
• Slug test results; *
• Aquifer test results;
• Plume's physical and chemical characterization; and
• Fracture trace study if groundwater in bedrock is impacted.
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August 12, 2014
* Check with the Regional Office prior to performing these tests
and study to see if necessary for the site.
K. Groundwater Modeling Results
Groundwater modeling or predictive calculations may be necessary at
some sites (source area proximate to surface water, source area located
within wellhead protection area or source area overlying semi -confined or
unconfined deeper Coastal Plain aquifer) to verify, based on site specific
hydrogeological conditions, whether groundwater contamination poses a
risk to receptors. For contamination shown to pose a risk to receptors,
groundwater modeling may be necessary to determine an appropriate
cleanup level for contaminated groundwater. Modeling should illustrate the
input data used to complete the model and will generally be required for
natural attenuation proposals (see Groundwater Modeling Policy at
http://portal. ncdenr.org/web/wq/aps/a-wr)ro/policy).
NOTE: Input data for models should be derived from site specific
information with limited assumptions or estimates. All assumptions and
estimated values including biodegradation rates must be conservative
(predict reasonable worst -case scenarios) and must be well documented.
L. Discussion
• Nature and extent of contamination, including primary and
secondary source areas, and impacted groundwater and
surface water resources;
• Maximum contaminant concentrations;
• Contaminant migration and potentially affected receptors
M. Conclusions and Recommendations
If corrective action will be necessary, provide a preliminary evaluation of
remediation alternatives appropriate for the site. Discuss the remediation
alternatives likely to be selected. Note that for impacts to groundwater
associated with permitted activities, corrective action pursuant to 15A
NCAC 2L .0106(k), (1) and (m) is not applicable, unless provided for
pursuant to 15A NCAC 2L .0106(c) and (e) or through a variance from the
Environmental Management Commission (EMC).
N. Figures
9 71/2 minute USGS topographic quadrangle map showing an area

August 12, 2014
within a minimum of a 1,500-foot radius of the source of
contamination and depicting the site location, all water supply wells,
public water supplies, surface water intakes, surface water bodies,
designated well head protection areas, and areas of recharge to
deeper aquifers in the Coastal Plain that are or may be used as a
source for drinking water;
Site map locating source areas, site boundaries, buildings, all water
supply wells within a minimum of 1,500 feet, named
roads/easements/right-of-ways, subsurface utilities, product or
chemical storage areas, basements and adjacent properties, scale
and north arrow;
At least two geologic cross sections through the saturated and
unsaturated zones intersecting at or near right angles through the
contaminated area using a reasonable vertical exaggeration.
Indicate monitoring well/sample boring/sample locations and
analytical results for soil samples. Identify the depth to the water
table. Provide a site plan showing the locations of the cross
sections;
■ Site map(s) showing the results of all soil sampling conducted.
Indicate sampling identifications, sampling depths, locations and
analytical results;
■ Site map(s) showing the results of all groundwater sampling
conducted. Indicate sampling locations, monitoring well
identifications, sample identifications, and analytical results;
Separate groundwater contaminant iso-concentration contour maps
showing total volatile organic compound concentrations, total
semi -volatile organic compound concentrations and concentrations
for the most extensive contaminant. Maps should depict the
horizontal and vertical extent. Contour line for applicable 2L
standard should be shown in bold;
■ Site map(s) showing the elevation of groundwater in the monitoring
wells and the direction of groundwater flow. Contour the
groundwater elevations. Identify and locate the datum (arbitrary
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August 12, 2014
1000, USGS, NGVD) or benchmark. Indicate the dates that water
level measurements were made. There should be one map for each
series of water level measurements obtained;
■ Groundwater contaminant iso-concentration contour cross-section;
and
■ Site map(s) showing the monitoring wells.
NDTE: If possible, use a single base map to prepare site maps using a
map scale of 9 inch = 40 feet (or a smaller scale for large sites, if
necessary). Maps and figures should include conventional symbols,
notations, labeling, legends, scales, and north arrows and should
conform to generally accepted practices of map presentation such as
those enumerated in the US Geological Survey pamphlet, "Topographic
Maps".
O. Tables
List all water supply wells, public or private, including irrigation wells
and unused wells, (omit those that have been properly abandoned
in accordance with 15A NCAC 2C .0100) within a minimum of 1500
feet of the known extent of contamination For each well, include the
well number (may use the tax map number), well owner and user
names, addresses and telephone numbers, use of the well, well
depth, well casing depth, well screen interval and distance from the
source of contamination;
List the names and addresses of property owners and occupants
within or contiguous to the area containing contamination and all
property owners and occupants within or contiguous to the area
where the contamination is expected to migrate;
■ List the results for groundwater samples collected including sample
location; date of sampling; sample collection procedures (bailer,
pump, etc.); sample identifications; sample analyses; and sample
analytical results (list any contaminant detected above the method
detection limit in bold); and
List for each monitoring well, the monitoring well identification
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August 12, 2014
numbers, date water levels were obtained, elevations of the water
levels, the land surface, top of the well casing, screened interval
and bottom of the well.
P Appendices
• Boring logs and lithological descriptions;
• Well construction records;
• Standard procedures used at site for sampling, field equipment
decontamination, field screening, etc.;
• Laboratory reports and chain -of -custody documents;
• Copies of any permits or certificates obtained, permit number,
permitting agency, and
• Modeling data and results;
• Slug/pumping test data; and
• Certification form for CSA
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August 12, 2014
DIVISION OF WATER RESOURCES
Certification for the Submittal of a Comprehensive Site Assessment
Responsible Party and/or Permittee:
Contact Person:
Address:
City: State: Zip Code:
Site Name:
Address:
City: State: Zip Code:
Groundwater Incident Number (applicable):
I, , a Professional Engineer/Professional Geologist
(circle one) for (firm or
company of employment) do hereby certify that the information indicated below is
enclosed as part of the required Comprehensive Site Assessment (CSA) and that
to the best of my knowledge the data, assessments, conclusions,
recommendations and other associated materials are correct, complete and
accurate.
(Each item must be initialed by the certifying licensed professional)
1. The source of the contamination has been identified. A list of all
potential
sources of the contamination are attached.
2. Imminent hazards to public health and safety have been identified.
3. Potential receptors and significant exposure pathways have been
identified.
4. Geological and hydrogeological features influencing the movement
of groundwater have been identified. The chemical and physical character of the
contaminants have been identified.
5. The CSA sufficiently characterizes the cause, significance and
extent of groundwater and soil contamination such that a Corrective Action Plan
can be developed. If any of the above statements have been altered or items not
initialed, provide a detailed explanation. Failure to initial any item or to provide
written justification for the lack thereof will result in immediate return of the CSA to
the responsible party.
(Please Affix Seal and Signature)
11