NC0004961_RBSS_Receptor Survey Report-FINAL_20141106

RIVERBEND STEAM STATION ASH BASIN
Drinking Water Supply Well
and Receptor Survey
NPDES Permit NC0004961

September 30, 2014

Duke Energy Carolinas, LLC I Riverbend Steam Station Ash Basin L1�
Drinking Water Supply We# and Receptor Survey rJ
REPORT VERIFICATION
Report Verification
PROJECT: DRINKING WATER SUPPLY WELL AND RECEPTOR SURVEY
RIVERBEND STEAM STATION ASH BASIN
NPDES PERMIT NC0004961
This document has been reviewed for accuracy and quality commensurate with the intended
application.
Prepared by: l4etut-
Checked by:
Approved by: 1
le"
Project Manager: Brooke Ahrens, PE
Date: R 1 3 I 1¢
Date: / 21D 41
Date: 9 3o //�

Duke Energy Carolinas, LLC | Riverbend Steam Station Ash Basin
Drinking Water Supply Well and Receptor Survey
TABLE OF CONTENTS

ii
Table of Contents
Page
Report Verification ....................................................................................................................... i
Table of Contents ........................................................................................................................ ii
Section 1 - Introduction .............................................................................................................. 1
Section 2 - Background .............................................................................................................. 3
2.1 Plant and Ash Basin Description .................................................................................. 3
2.2 Description of Surrounding Properties .......................................................................... 4
Section 3 – Drinking Water Supply Well and Receptor Survey Activities and Findings ............... 5
3.1 NCDENR Records Review ........................................................................................... 5
3.2 Local/Regional Water Agency Records Review ........................................................... 5
3.3 Mecklenburg County Records Review ......................................................................... 6
3.4 Gaston County Records Review .................................................................................. 6
3.5 Utility Department Records Review .............................................................................. 6
3.6 HDR Field Survey ........................................................................................................ 7
3.7 Additional Survey Activities .......................................................................................... 8
3.8 USGS Hydrography Review ......................................................................................... 8
Section 4 - Site Geology and Hydrogeology ............................................................................... 9
4.1 Generalized Site Hydrogeologic Conceptual Model ..................................................... 9
4.2 Site Geology and Hydrogeology ..................................................................................10
4.3 Groundwater Flow Directions ......................................................................................11
Section 5 - Summary of Findings ..............................................................................................14
Section 6 - References ..............................................................................................................15

Figures
Figure 1 Site Location Map
Figure 2 Site Layout
Figure 3 Drinking Water Supply Well and Receptor Survey Map

Tables
Table 1 Water Supply Well Information

Appendices
Appendix A EDR GeoCheck Report
Duke Energy Carolinas, LLC | Riverbend Steam Station Ash Basin
Drinking Water Supply Well and Receptor Survey
SECTION 1 - INTRODUCTION

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Section 1 - 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. Coal ash residue from RBSS’s coal
combustion process was disposed 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.
The Coal Ash Management Act 2014 – General Assembly of North Carolina Senate Bill 729
Ratified Bill (Session 2013) (SB 729) revised North Carolina General Statute 130A-309.209(c)
to require:
No later than October 1, 2014, the owner of a coal residuals surface
impoundment shall conduct a Drinking Water Supply Well Survey that identifies
all drinking water supply wells within one-half mile down-gradient from the
established compliance boundary of the impoundment and submit the Survey to
the Department.
On August 13, 2014, Duke Energy received a Notice of Regulatory Requirements (NORR) for
the 14 Coal Ash Facilities owned by Duke Energy in North Carolina. The 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.
Duke Energy Carolinas, LLC | Riverbend Steam Station Ash Basin
Drinking Water Supply Well and Receptor Survey
SECTION 1 - INTRODUCTION

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HDR has completed this Drinking Water Supply Well and Receptor Survey (Survey) to satisfy
the requirements outlined in SB 729 and the NORR. The scope of this Survey includes
identification of all receptors within a 0.5-mile radius (2,640 feet) of the RBSS ash basin
compliance boundary based on the requirements set forth in 15A NCAC 02L .0106(g). The
receptors include 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. HDR also identified public water supplies and wellhead protection areas
(if present) 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 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 Survey activities
performed and the findings of those activities are presented in Section 3 and on Figure 3. Table
1 includes the well owner’s name and location address with an identifier which corresponds to
the water supply well identifier on Figure 3. A potential area of interest with respect to the
RBSS ash basin groundwater flow has been delineated on Figure 3. This area is considered to
be potentially downgradient of the RBSS ash basin, based on available information.

Duke Energy Carolinas, LLC | Riverbend Steam Station Ash Basin
Drinking Water Supply Well and Receptor Survey
SECTION 2 - BACKGROUND

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Section 2 - Background
2.1 Plant and Ash Basin 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.
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 were 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 | Riverbend Steam Station Ash Basin
Drinking Water Supply Well and Receptor Survey
SECTION 2 - BACKGROUND

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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.
2.2 Description of Surrounding Properties
Properties located within a 0.5-mile radius of the RBSS ash basin compliance boundary and
north of Mountain Island Lake are located in Huntersville, Mecklenburg County, North Carolina.
These properties are primarily comprised of a wildlife refuge and a nature preserve. One
residential property is located northeast of the ash basin compliance boundary within the
0.5-mile radius.
Properties located within the 0.5-mile radius of the RBSS ash basin compliance boundary and
south of Mountain Island Lake are located in Mount Holly, Gaston County, North Carolina. The
majority of the property in this area is owned by Duke Energy and associated with the RBSS.
Residential properties are located south and southeast of the ash basin compliance boundary to
the south of Horseshoe Bend Beach Road within the 0.5-mile radius.
Figure 3 depicts these properties surrounding RBSS.

Duke Energy Carolinas, LLC | Riverbend Steam Station Ash Basin
Drinking Water Supply Well and Receptor Survey
SECTION 3 – DRINKING WATER SUPPLY WELL AND RECEPTOR SURVEY ACTIVITIES AND FINDINGS

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Section 3 – Drinking Water Supply Well and
Receptor Survey Activities and Findings
3.1 NCDENR Records Review
On July 10, 2014, Mr. Justin Schumacher with HDR contacted by telephone Mr. Sean McGuire,
Geographic Information System (GIS) Specialist with the NCDENR Department of
Environmental Health (DEH) Public Water Supply Section (PWSS). Mr. McGuire stated that the
Public Water Supply Water Sources GIS point data set was in the process of being updated.
The most current GIS data set of public water supply locations available from North Carolina
state agencies was provided by Mr. McGuire via electronic mail on July 14, 2014. The GIS
point data for the public water supply wells includes, but is not limited to, information such as
public water supply (PWS) system identification numbers, ownership information, PWS source
type, well depth, and well yield. HDR reviewed the GIS data set to identify public water supply
sources within a 0.5-mile radius of the RBSS ash basin compliance boundary.
On August 8, 2014, HDR reviewed the NCDENR Division of Water Resources (DWR) Source
Water Assessment Program (SWAP) online database for public water supply sources to identify
any wells located within a 0.5-mile radius of the ash basin compliance boundary, confirm the
location of wells included in the Public Water Supply Water Sources GIS point data set, and
identify any wellhead protection areas located within a 0.5-mile radius of the compliance
boundary. The NCDENR SWAP database provides detailed assessments of all public drinking
water intakes and wellhead protection areas in North Carolina. The website address is:
http://swap.ncwater.org/website/swap/viewer.htm.
No public water supply wells were identified in the Public Water Supply Water Sources GIS
point data set or on the NCDENR SWAP online database within a 0.5-mile radius of the RBSS
ash basin compliance boundary.
No wellhead protection areas were identified on the NCDENR SWAP online database within a
0.5-mile radius of the RBSS ash basin compliance boundary.
3.2 Local/Regional Water Agency Records Review
HDR contacted EDR to conduct a local/regional water agency records review for water supply
wells within a 1-mile radius of the RBSS ash basin. A copy of the EDR Geocheck Report
(Inquiry Number 4073890.1s) dated September 22, 2014, is provided in Appendix A.
The EDR report identified two wells within the 0.5-mile radius of the RBSS ash basin
compliance boundary that are listed on the Federal United States Geological Survey (USGS)
database. The two wells queried on the USGS National Water Information System: Web
Interface (http://waterdata.usgs.gov/nc/nwis/inventory). Based on the latitude and longitude
provided for the two wells in the database, they were determined to be located on the RBSS
Duke Energy Carolinas, LLC | Riverbend Steam Station Ash Basin
Drinking Water Supply Well and Receptor Survey
SECTION 3 – DRINKING WATER SUPPLY WELL AND RECEPTOR SURVEY ACTIVITIES AND FINDINGS

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property. Duke Energy personnel indicated that water supply wells were never present onsite in
the locations provided in the USGS database.
The EDR report identified one well within the 0.5-mile radius of the RBSS ash basin compliance
boundary that is listed on the Federal Data Reporting System (FRDS) Public Water Supply
System database. Public Water Supply well PWS: NC01367706 was confirmed by Duke
Energy personnel to be located on the RBSS property. Duke Energy personnel stated that the
latitude and longitude coordinates provided in the database for this well were not accurate. The
location of the well included on Figure 3 is based on a discussion with Donna Burrell with Duke
Energy regarding the location of this well. According to Duke Energy personnel, this well is no
longer used as a drinking water supply well for the station as it was prior to March 2001 when
the station was reportedly connected to the Mount Holly Public Utilities Department. Available
information pertaining to this well is included on Table 1.
3.3 Mecklenburg County Records Review
On August 14, 2014, HDR reviewed Mecklenburg County’s Groundwater and Wastewater
Services Well Information System online database to identify any private or public water supply
wells located in Mecklenburg County within a 0.5-mile radius of the ash basin compliance
boundary. Established in 2002, the database provides Mecklenburg County’s collection of data
about well and septic system permitting, subsurface investigation permitting, monitoring well
registration and abandonment, and Mecklenburg County Priority List contamination sites. The
website address is: http://meckmap.mecklenburgcountync.gov/WIS_3/index.html.
No private or public water supply wells were identified on the Mecklenburg County Groundwater
and Wastewater Services Well Information System online database located within a 0.5-mile
radius of the ash basin compliance boundary.
3.4 Gaston County Records Review
HDR contacted the Gaston County Environmental Health Department to inquire about the
location and details (if available) for registered water supply wells located in Gaston County
within a 0.5-mile radius of the ash basin compliance boundary. On August 14, 2014, Mr. Justin
Schumacher with HDR contacted Ms. Samantha Dye, Assistant Administrator with the Gaston
County Environmental Health Department. Ms. Dye informed Mr. Schumacher that she
researched Gaston County’s records which date back to 1989 for private and/or public water
supply wells within a 0.5-mile radius of the ash basin compliance boundary.
The Gaston County Environmental Health Department has no records of private or public water
supply wells located within a 0.5-mile radius of the ash basin compliance boundary.
3.5 Utility Department Records Review
HDR contacted Charlotte-Mecklenburg Utilities Department (CMUD) to inquire about municipal
water supply to properties located in Mecklenburg County within a 0.5-mile radius of the ash
basin compliance boundary. Prior to contacting CMUD, HDR personnel reviewed
orthophotography obtained from NC OneMap GeoSpatial portal (dated 2010) and identified one
Duke Energy Carolinas, LLC | Riverbend Steam Station Ash Basin
Drinking Water Supply Well and Receptor Survey
SECTION 3 – DRINKING WATER SUPPLY WELL AND RECEPTOR SURVEY ACTIVITIES AND FINDINGS

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residential property located in Mecklenburg County within a 0.5-mile radius of the ash basin
compliance boundary northeast of RBSS. On August 14, 2014, Mr. Justin Schumacher
contacted Mecklenburg County “Citizen Service/311” to inquire about municipal water supply to
the identified residence. CMUD does not have record of the residential property being
connected to the municipal water and sewer system.
Based on CMUD not providing water service to the residence identified and no record of a
private water supply well identified on the Mecklenburg County Groundwater and Wastewater
Services Well Information System online database, it is assumed that the residence is serviced
by an unregistered private water supply well (well 3). The approximate location of the assumed
private water supply well is shown on Figure 3. Available information for the property on which
the assumed well is located is provided in Table 1.
HDR contacted the Mount Holly Public Utilities Department to inquire about municipal water
supply to properties located in Mount Holly and Gaston County within a 0.5-mile radius of the
ash basin compliance boundary. On August 14, 2014, Mr. Schumacher spoke with Mr. Don
Petty with the Mount Holly Public Utilities Department billing department.
Mr. Petty confirmed that the Mount Holly Public Utilities Department provides municipal water
service to the RBSS site and the properties located in Gaston County within a 0.5-mile radius of
the ash basin compliance boundary.
3.6 HDR Field Survey
HDR personnel performed a field reconnaissance on January 27, 2014, to identify public and
private water supply wells (including irrigation wells and unused or abandoned wells) and
surface water features located within a 0.5-mile radius of the RBSS ash basin compliance
boundary. A windshield survey was conducted from public roadways to identify water meters,
fire hydrants, valves, and any potential well heads/well houses. Prior to conducting the field
reconnaissance, HDR personnel reviewed orthophotography obtained from NC OneMap
GeoSpatial portal (dated 2010) to identify any potential well heads/well houses and surface
waters within a 0.5-mile radius of the ash basin compliance boundary.
In addition, HDR personnel contacted Duke Energy site personnel to identify water supply wells
located on Duke Energy property.
HDR field personnel did not identify private or public water supply wells (including irrigation
wells and unused or abandoned wells) located outside of Duke Energy’s property within a 0.5-
mile radius of the ash basin compliance boundary during the field reconnaissance. Duke
Energy personnel familiar with water supply wells at RBSS reported that three wells are present
on Duke Energy’s property. These wells (PWS: NC01367706, W ell 1, and Well 2) are identified
on Figure 3 and available property and well information is provided in Table 1. Duke Energy
personnel indicated that these three wells are not used for drinking water supply. Duke Energy
personnel reported that the wells do not appear to be abandoned but are not currently in use.
Well 1 located near the Lark Maintenance Area has reportedly never been used for a drinking
Duke Energy Carolinas, LLC | Riverbend Steam Station Ash Basin
Drinking Water Supply Well and Receptor Survey
SECTION 3 – DRINKING WATER SUPPLY WELL AND RECEPTOR SURVEY ACTIVITIES AND FINDINGS

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water supply and may be used for irrigation purposes only. The use of Well 2 is reportedly
unknown but may have been used as a drinking water source in the past.
Water meters, fire hydrants, and valve markings were identified at properties with structures
located in Gaston County within a 0.5-mile radius of the ash basin compliance boundary.
From the public roadway, HDR personnel did not identify indications of municipal water supply
for the properties located in Mecklenburg County within a 0.5-mile radius of the ash basin
compliance boundary.
3.7 Additional Survey Activities
HDR is in the process of mailing drinking water supply well survey questionnaires to property
owners within a 0.5-mile radius of the RBSS ash basin compliance boundary requesting
information on the presence of water supply wells and well usage for the properties. The results
of the well survey questionnaires will be submitted to NCDENR by November 7, 2014.
3.8 USGS Hydrography Review
HDR reviewed the USGS National Hydrography Dataset (NHD) obtained from the USGS
National Map Viewer (http://viewer.nationalmap.gov/viewer/) to identify any surface waters
features within a 0.5-mile radius of the ash basin compliance boundary. Hydrography data
obtained from the USGS NHD is included on Figure 3.
Duke Energy Carolinas, LLC | Riverbend Steam Station Ash Basin
Drinking Water Supply Well and Receptor Survey
SECTION 4 - SITE GEOLOGY AND HYDROGEOLOGY

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Section 4 - Site Geology and Hydrogeology
4.1 Generalized Site Hydrogeologic Conceptual Model
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
Duke Energy Carolinas, LLC | Riverbend Steam Station Ash Basin
Drinking Water Supply Well and Receptor Survey
SECTION 4 - SITE GEOLOGY AND HYDROGEOLOGY

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discharge occurs in lowland areas bordering surface water bodies, marshes, and floodplains
(LeGrand 2004).
4.2 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.
Duke Energy Carolinas, LLC | Riverbend Steam Station Ash Basin
Drinking Water Supply Well and Receptor Survey
SECTION 4 - SITE GEOLOGY AND HYDROGEOLOGY

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4.3 Groundwater Flow Directions
In 2011, Duke Energy provided Altamont Environmental, Inc. (Altamont) information on the
groundwater monitoring wells installed at the ash basin and information on the water levels in
the ash basin. Altamont utilized this information along with consideration of adjacent bodies of
water and site topography to develop generalized groundwater direction flow arrows for the
areas adjacent to the ash basins. This information was presented in the report titled
Generalized Groundwater Flow Direction Maps for Ash Basins, Duke Energy Carolinas, LLC,
Fossil Stations, December 12, 2011. The report contained figures with similar generalized
groundwater flow arrows for all seven of the Duke Energy Carolinas fossil station ash basins.
The information from that report is used with the permission of Duke Energy.
As stated in Section 3.0 of the Altamont report:
The purpose of the Generalized Ash Basin Groundwater Flow Direction Maps,
Figures 1 through 7, is to provide Duke with an interpretation of the generalized
groundwater flow directions in the areas surrounding the ash basins. The maps
were developed utilizing existing data that were readily available and with data
collected as part of on-going monitoring at the ash basins. No additional field
investigation was conducted as part of the development of the maps.
The maps are not intended to provide absolute groundwater flow direction data at
a specific location. Rather, they are an interpretation of the generalized
groundwater flow direction for the shallow water table based on readily available
data.
As described in the following sections (Section 4.0, Section 5.0, and Section 6.0),
there may be hydrogeologic conditions present at the ash basins that cause
groundwater flow conditions to differ from the generalized groundwater flow
directions shown on Figures 1 through 7.
The generalized groundwater flow directions were determined based on a consideration of the
information described above, most notably that the sites are located in the Piedmont
physiographic province. In addition, the generalizations of typical Piedmont hydrogeology found
in A Master Conceptual Model for Hydrogeological Site Characterization in the Piedmont and
Mountain Region of North Carolina (LeGrand 2004) apply to these sites.
As stated in Section 5.0 of the Altamont report, the possible effects of pumping from adjacent
water supply wells were not considered in the development of the generalized groundwater flow
direction arrows.
The groundwater elevations used in development of the generalized groundwater direction flow
arrows were from the compliance groundwater monitoring wells (compliance wells) monitored in
association with the NPDES permits and from groundwater monitoring wells voluntarily
(voluntary wells) installed by Duke Energy. Groundwater elevation data readings have not been
Duke Energy Carolinas, LLC | Riverbend Steam Station Ash Basin
Drinking Water Supply Well and Receptor Survey
SECTION 4 - SITE GEOLOGY AND HYDROGEOLOGY

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routinely measured in the voluntary wells since January 2012. The compliance wells were
installed in 2010 and 2011.
Section 7.0 of the Altamont report discusses the development of the generalized groundwater
flow direction arrows and the relative level of confidence in the interpretation of the generalized
flow direction as follows:
Groundwater flow direction arrows are used to depict the interpreted direction of
generalized groundwater flow. Three different colors of arrows were used to
indicate the relative level of confidence in the interpretation of the generalized
groundwater flow direction.
The relative level of confidence in the interpretation of flow direction was
determined by:
 The distance from groundwater monitoring wells or surface water elevation
data
 The number of groundwater data elevation points utilized
 Consideration of the surface topography
Descriptions of the relative confidence levels indicated by groundwater flow
direction arrow colors are as follows:
 Black arrows represent high confidence in the groundwater flow direction
interpretation. The black arrows were used in areas in which there were
several known groundwater or surface water elevation data points and the
surface topography supported the interpretation of groundwater flow
characteristic of typical Piedmont groundwater flow.
 Gray arrows represent moderate confidence in the groundwater flow direction
interpretation. The gray arrows were used in areas where at least one
groundwater or surface water elevation point was known or in areas where
there was strong surface topographic data to support the groundwater flow
direction interpretation.
 White arrows represent estimated groundwater flow direction interpretation.
The white arrows were used in areas where there was little or no
groundwater or surface water elevation data and there was not conclusive
surface topographic data to support a gray arrow.
Since limited groundwater elevation data readings were performed on the voluntary wells after
January 2012, HDR reviewed the historic groundwater level data available from the compliance
groundwater monitoring wells in conjunction with the current approximate ash basin pond
elevation data.
Duke Energy Carolinas, LLC | Riverbend Steam Station Ash Basin
Drinking Water Supply Well and Receptor Survey
SECTION 4 - SITE GEOLOGY AND HYDROGEOLOGY

13
HDR found the generalized groundwater flow direction arrows presented in the Altamont report
to generally represent the probable direction of groundwater flow for the shallow water table
aquifer based on available data. As stated in the Altamont report, the generalized groundwater
flow direction arrows present an interpretation of flow direction based on data from the shallow
water table aquifer and do not consider the possible effects of pumping from adjacent water
supply wells.
The generalized groundwater flow directions for the area adjacent to the RBSS ash basin are
found on Figure 3.
Based on the site generalized hydrogeological conceptual model by LeGrand, groundwater
levels measured in the site monitoring wells and the generalized groundwater flow direction
arrows, a potential area of interest with respect to the RBSS ash basin groundwater flow has
been delineated on Figure 3. This area is considered to be potentially downgradient of the
RBSS ash basin, based on available information. The groundwater flow direction on the south
side of the area of interest is inferred due to lack of groundwater data and/or strong topographic
data. Mountain Island Lake is expected to be the groundwater discharge region for
groundwater flow from the ash basin and is considered to be a hydrologic boundary for
groundwater flow between the ash basin and the properties to the north of Mountain Island
Lake. All of the property within the potential area of interest is owned by Duke Energy.
Duke Energy will be installing additional groundwater monitoring wells onsite as part of a RBSS
ash basin comprehensive site assessment. The groundwater flow across the site will be
reviewed after the new groundwater elevation data from these monitoring wells are available.
Duke Energy Carolinas, LLC | Riverbend Steam Station Ash Basin
Drinking Water Supply Well and Receptor Survey
SECTION 5 - SUMMARY OF FINDINGS

14
Section 5 - Summary of Findings
A summary of the receptor Survey findings is provided below. The identified water supply wells
(including irrigation wells and unused or abandoned wells) are shown on Figure 3. Available
property and well information for the identified wells is provided in Table 1.
 One private water supply well is assumed to provide water to the residence located to
the northeast of RBSS within a 0.5-mile radius of the ash basin compliance boundary.
This well is located across Mountain Island Lake in Mecklenburg County (Well 3).
 Two private water supply wells were reported at the RBSS site. The wells are reportedly
not currently used for drinking water supply. One of the wells has reportedly never been
used for drinking water supply and was used for irrigation purposes only. Duke Energy
personnel report that the wells do not appear to be abandoned and are not currently in
use (W ell 1 and Well 2).
 One public water supply well (PWS: NC0136706) was reported at the RBSS site. Duke
Energy personnel report that the well does not appear to be abandoned and is not
currently in use.
 No wellhead protection areas were identified within a 0.5-mile radius of the ash basin
compliance boundary.
 Several surface water features that flow toward Mountain Island Lake were identified
within a 0.5-mile radius of the ash basin.
 No water supply wells (including irrigation wells and unused or abandoned wells) were
identified within the ash basin potential area of interest.
 A report with the results from the water supply well questionnaire mailings will be sent to
NCDENR by November 7, 2014.
Duke Energy Carolinas, LLC | Riverbend Steam Station Ash Basin
Drinking Water Supply Well and Receptor Survey
SECTION 6 - REFERENCES

15
Section 6 - References
Altamont Environmental, Inc. Generalized Groundwater Flow Direction Maps for Ash Basins,
Duke Energy Carolinas, LLC, Fossil Stations, December 12, 2011.
Fenneman, Nevin Melancthon. Physiography of eastern United States. McGraw-Hill. 1938.
Goldsmith, R., Milton, D. J., and Horton, J. W, Jr. 1988. Geologic map of the Charlotte 1° x 2°
quadrangle, North Carolina and South Carolina: United States Geological Survey,
Miscellaneous Investigations Series, Map I-1251-E, scale 1:250,000.
LeGrand, Harry, Sr. 2004. A Master Conceptual Model for Hydrogeological Site
Characterization in the Piedmont and Mountain Region of North Carolina, North Carolina
Department of Environment and Natural Resources.
Pippin, Charles, G., Chapman, Melinda, J., Huffman, Brad A., Heller, Matthew J., and Schelgel,
Melissa E. 2008. Hydrogeologic Setting, Ground-Water Flow, and Ground-Water
Quality at the Langtree Peninsula Research Station, Iredell County, North Carolina,
2000-2005, United States Geological Survey, Prepared in cooperation with the North
Carolina Department of Environment and Natural Resources, Division of Water Quality.

Figures

/\\Bridge
NOTES:
I. SOURCES: USGS TOPOGRAPHIC MAP - MT. ISLAND LAKE,
CREATED 1993. USGS TOPOGRAPHIC MAP - LAKE NORMAN
SOUTH, CREATED 1993.
SCALE (FEET)
1000 0 1000 2000
r q8
SITE LOCATION MAP
DUKE ENERGY CAROLINAS, LLC
RIVERBEND STEAM STATION ASH BASIN
NPDES PERMIT #NC0004961
GASTON COUNTY, NORTH CAROLINA
DATE
SEPT. 30, 2014
FIGURE 1

'p
c
ASH STORAGE
MW-15
MW-11SR
MW-11DR
MW-4S
MW-4D
MW 33S 'dw RAMA 2
,/,mw-3D\\,
MW-2S
ASH BASIN
MW-2D SECONDARY CELL
P, MW-8S
�� MAN-81✓
ASH BASIN
PRIMARY CELL
(.1
MW-5S
MW-5D
mw s
F PI r,,AxAi- r%
MW-14
. d, \ \ \\
�\ � rim �� i ��1�/�� �� � �f -� � �»>1 •
� ljf�ll
LEGEND:
x\ �� �\
DUKE ENERGY PROPE
ASH BASIN COMPLIAN
PF MW-M.",
„\.� f i
ASH BASIN COMPLIAN
MW-7D WITH DUKE ENERGY
ASH BASIN WASTE Bil
� (BACKGROUND)
ASH OR CINDER STOR
HORSESHOE BEND BEACH ROAD TOPOGRAPHIC CONTI
ti ASH BASIN COMPLIAN
MONITORINGWELL
ASH BASIN VOLU NITA
MONITORINGWELL
STREAM

NOTES:
1. PARCEL DATA FOR THE SITE WAS OBTAINED FROM DUKE ENERGY REAL ESTATEAND ISAPPROXIMATE.
2. PARCEL DATA OTHER THAN THE DUKE ENERGY PROPERTY WERE OBTAINED FROM THEGASTON COUNTY GIS WEBSITE.
3. ORTHOPHOTOGRAPHY WAS OBTAINED FROM NC ONEMAP GISWEB SITE(DATED 2009).
4. THE COMPLIANCE BOUNDARY IS ESTABLISHED ACCORDING TO THE DEFINITION FOUND IN 15A NCACO2L.0107 {a}.
5. MECKLENBURG COUNTY BOUNDARY LINE OBTAINED FROM MECKLENBURG COUNTY GIS OPEN MAPPING DATA PORTAL ON JANUARY 30,2014
6. THE LOCATION OF THE ASSUMED PRIVATE WATER SUPPLY WELL IS APPROXIMATE AND BASED ON THE LACK OF RECORDSOF WATERSUPPLY
SERVICE AT THE RESIDENCES LOCATED IN MECKLENBURG COUNTY.
7. HYDROGRAPHY WAS OBTAINED FROM THE USGS NATIONAL MAP VIEWER DOWNLOAD PLATFORM ON MARCH 24,2014
http://nationalmap.gov/viewer.htmi) AND FROM HDR's FIELD RECONNAISSANCE.
S. REPORTED WATER SUPPLY WELL LOCATIONS WERE PROVIDED BY DUKE ENERGY AND ARE APPROXIMATE.
SCALE (FEET)
300' 0 500' 600'
/" - 600'
DRINKING WATER SUPPLY WELL AND
RECEPTOR SURVEY MAP
DUKE ENERGY CAROLINAS, LLC
RIVERBEND STEAM STATION ASH BASIN
DATE
SEPT, 30, 2014
FIGURE
9. ASH STORAGE BOUNDARY AND CINDER STORAGE BOUNDARY ARE APPROXIMATE.
10. AS -BUILT MONITORING WELL LOCATIONS PROVIDED BY DUKE ENERGY.
11. SHALLOW MONITORING WELLS {S} - WELL SCREEN INSTALLED ACROSS THE SURFICIAL WATER TABLE.
12. DEEP MONITORING WELLS {D} - WELL SCREEN INSTALLED IN THE TRANSITION ZONE BETWEEN COMPETENT BEDROCKANDTHE REGOLITH.
13. TOPOGRAPHY DATA FOR THE SITE WAS OBTAINED FROM NCDOT GEOGRAPHIC INFORMATION SYSTEM {GIS} WEB SITE.
NPDES PERMIT #NC0004961
GASTON COUNTY, NORTH CAROLINA
0

Tables

Table 1
Public and Private Water Supply Wells
Within 0.5 Mile Radius of Riverbend Ash Basin Compliance Boundary
Duke Energy Carolinas, LLC/Riverbend Steam Station
Well ID
(shown on Figure 3)
Public Water
System Name Well Owner/ User Property Address
(well location)Parcel ID Number Reported
Well Use
Distance from
Ash Basin
Compliance
Boundary (ft)
Direction from
Ash Basin
Well
Depth
(ft-bgs)
Well
Casing
Depth
(ft-bgs)
Well
Yield
(gpm)
PWS: NC01367706
Duke Power -
Riverbend Steam
Station
Duke Energy Carolinas, LLC
(owner)
175 Steam Plant Road
Mount Holly, NC 28120
175033
(Gaston County)
Unknown
(reported by Duke Energy
as not used for drinking
water once station
connected to Mount Holly
Public Utilities
Department in March
2001)
Approx. 625 Southwest N/A N/A N/A
1 N/A Duke Energy Carolinas, LLC
(owner)
175 Steam Plant Road
Mount Holly, NC 28120
175022
(Gaston County)Irrigation Approx. 1,975 West N/A N/A N/A
2 N/A Duke Energy Carolinas, LLC
(owner)
175 Steam Plant Road
Mount Holly, NC 28120
175033
(Gaston County)
Unknown
(reported by Duke Energy
as may have been used for
drinking water)
Approx. 1,750 Southwest N/A N/A N/A
3 N/A Eugenia and Robert White
(property owner)
4050 Neck Rd
Huntersville, NC 28078
1318106
(Mecklenburg County)Assumed Domestic Approx. 2,300 Northeast N/A N/A N/A
Notes:
1. Well locations are shown on Figure 3.
2. Owner and property address information for water supply wells obtained from Mecklenburg County's online Property Ownership and Land Records Information System (POLARIS).
3. Distances between water supply wells and the ash basin compliance boundary are approximate.
4. N/A indicates not available.
5. (ft-bgs) indicates feet below ground surface.
6. (gpm) indicates gallons per minute.
Recorded Water Supply Wells
Assumed Water Supply Wells
Public Water Supply Wells
Page 1 of 1

Appendix A
EDR GeoCheck Report
Riverbend Steam Station
175 Steam Plant Road, Mounty Holly, NC
Inquiry Number: 4073890.1s
September 22, 2014

FORM-NULL-SPM
tropeR ®kcehCoeG RDE ehT
6 Armstrong Road, 4th floor
Shelton, CT 06484
Toll Free: 800.352.0050
www.edrnet.com
Riverbend Steam Station
175 Steam Plant Road
Mount Holly, NC 28120
Inquiry Number: 4073890.1s
September 22, 2014
SECTION PAGE
GEOCHECK ADDENDUM
Physical Setting Source Addendum A-1
Physical Setting Source Summary A-2
Physical Setting Source Map A-7
Physical Setting Source Map Findings A-8
Physical Setting Source Records Searched PSGR-1
TC4073890.1s Page 1
Thank you for your business.
Please contact EDR at 1-800-352-0050
with any questions or comments.
Disclaimer - Copyright and Trademark Notice
This Report contains certain information obtained from a variety of public and other sources reasonably available to Environmental Data
Resources, Inc. It cannot be concluded from this Report that coverage information for the target and surrounding properties does not exist from
other sources. NO WARRANTY EXPRESSED OR IMPLIED, IS MADE WHATSOEVER IN CONNECTION WITH THIS REPORT. ENVIRONMENTAL
DATA RESOURCES, INC. SPECIFICALLY DISCLAIMS THE MAKING OF ANY SUCH WARRANTIES, INCLUDING WITHOUT LIMITATION,
MERCHANTABILITY OR FITNESS FOR A PARTICULAR USE OR PURPOSE. ALL RISK IS ASSUMED BY THE USER. IN NO EVENT SHALL
ENVIRONMENTAL DATA RESOURCES, INC. BE LIABLE TO ANYONE, WHETHER ARISING OUT OF ERRORS OR OMISSIONS, NEGLIGENCE,
ACCIDENT OR ANY OTHER CAUSE, FOR ANY LOSS OF DAMAGE, INCLUDING, WITHOUT LIMITATION, SPECIAL, INCIDENTAL,
CONSEQUENTIAL, OR EXEMPLARY DAMAGES. ANY LIABILITY ON THE PART OF ENVIRONMENTAL DATA RESOURCES, INC. IS STRICTLY
LIMITED TO A REFUND OF THE AMOUNT PAID FOR THIS REPORT. Purchaser accepts this Report "AS IS". Any analyses, estimates, ratings,
environmental risk levels or risk codes provided in this Report are provided for illustrative purposes only, and are not intended to provide, nor
should they be interpreted as providing any facts regarding, or prediction or forecast of, any environmental risk for any property. Only a Phase I
Environmental Site Assessment performed by an environmental professional can provide information regarding the environmental risk for any
property. Additionally, the information provided in this Report is not to be construed as legal advice.
Copyright 2014 by Environmental Data Resources, Inc. All rights reserved. Reproduction in any media or format, in whole
or in part, of any report or map of Environmental Data Resources, Inc., or its affiliates, is prohibited without prior written permission.
EDR and its logos (including Sanborn and Sanborn Map) are trademarks of Environmental Data Resources, Inc. or its affiliates. All other
trademarks used herein are the property of their respective owners.
TABLE OF CONTENTS
TC4073890.1s Page 1
geologic strata.
of the soil, and nearby wells. Groundwater flow velocity is generally impacted by the nature of the
Groundwater flow direction may be impacted by surface topography, hydrology, hydrogeology, characteristics
2. Groundwater flow velocity.
1. Groundwater flow direction, and
Assessment of the impact of contaminant migration generally has two principal investigative components:
forming an opinion about the impact of potential contaminant migration.
EDR’s GeoCheck Physical Setting Source Addendum is provided to assist the environmental professional in
1996Most Recent Revision:
35080-D8 LAKE NORMAN SOUTH, NCNorth Map:
1997Most Recent Revision:
35080-C8 MOUNTAIN ISLAND LAKE, NCTarget Property Map:
USGS TOPOGRAPHIC MAP
685 ft. above sea levelElevation:
3913489.8UTM Y (Meters):
503406.7UTM X (Meters):
Zone 17Universal Tranverse Mercator:
80.9625 - 80˚ 57’ 45.00’’Longitude (West):
35.3665 - 35˚ 21’ 59.40’’Latitude (North):
TARGET PROPERTY COORDINATES
MOUNT HOLLY, NC 28120
175 STEAM PLANT ROAD
RIVERBEND STEAM STATION
TARGET PROPERTY ADDRESS
®GEOCHECK - PHYSICAL SETTING SOURCE REPORT ®
TC4073890.1s Page 2
should be field verified.
on a relative (not an absolute) basis. Relative elevation information between sites of close proximity
Source: Topography has been determined from the USGS 7.5’ Digital Elevation Model and should be evaluated
SURROUNDING TOPOGRAPHY: ELEVATION PROFILES
Elevation (ft)Elevation (ft)TP
TP
0 1/2 1 Miles✩Target Property Elevation: 685 ft.
North South
West East720712694722718733790745747685685687649649649674690713754650658662650637649649689719685685690674682711649649649649General NorthGeneral Topographic Gradient:
TARGET PROPERTY TOPOGRAPHY
should contamination exist on the target property, what downgradient sites might be impacted.
assist the environmental professional in forming an opinion about the impact of nearby contaminated properties or,
Surface topography may be indicative of the direction of surficial groundwater flow. This information can be used to
TOPOGRAPHIC INFORMATION
collected on nearby properties, and regional groundwater flow information (from deep aquifers).
sources of information, such as surface topographic information, hydrologic information, hydrogeologic data
using site-specific well data. If such data is not reasonably ascertainable, it may be necessary to rely on other
Groundwater flow direction for a particular site is best determined by a qualified environmental professional
GROUNDWATER FLOW DIRECTION INFORMATION
®GEOCHECK - PHYSICAL SETTING SOURCE SUMMARY®
TC4073890.1s Page 3
Not Reported
GENERAL DIRECTIONLOCATION
GROUNDWATER FLOWFROM TPMAP ID
hydrogeologically, and the depth to water table.
authorities at select sites and has extracted the date of the report, groundwater flow direction as determined
flow at specific points. EDR has reviewed reports submitted by environmental professionals to regulatory
EDR has developed the AQUIFLOW Information System to provide data on the general direction of groundwater
AQUIFLOW®
Search Radius: 1.000 Mile.
contamination exist on the target property, what downgradient sites might be impacted.
environmental professional in forming an opinion about the impact of nearby contaminated properties or, should
of groundwater flow direction in the immediate area. Such hydrogeologic information can be used to assist the
Hydrogeologic information obtained by installation of wells on a specific site can often be an indicator
HYDROGEOLOGIC INFORMATION
YES - refer to the Overview Map and Detail MapMOUNTAIN ISLAND LAKE
NATIONAL WETLAND INVENTORY
NWI Electronic
Data CoverageNWI Quad at Target Property
37119C - FEMA DFIRM Flood dataAdditional Panels in search area:
37071C - FEMA DFIRM Flood dataFlood Plain Panel at Target Property:
YES - refer to the Overview Map and Detail MapGASTON, NC
FEMA FLOOD ZONE
FEMA Flood
Electronic DataTarget Property County
and bodies of water).
Refer to the Physical Setting Source Map following this summary for hydrologic information (major waterways
contamination exist on the target property, what downgradient sites might be impacted.
the environmental professional in forming an opinion about the impact of nearby contaminated properties or, should
Surface water can act as a hydrologic barrier to groundwater flow. Such hydrologic information can be used to assist
HYDROLOGIC INFORMATION
®GEOCHECK - PHYSICAL SETTING SOURCE SUMMARY®
TC4073890.1s Page 4

> 60 inchesDepth to Bedrock Max:
> 60 inchesDepth to Bedrock Min:
HIGH Corrosion Potential - Uncoated Steel:
Hydric Status: Soil does not meet the requirements for a hydric soil.
water table is more than 6 feet.
Well drained. Soils have intermediate water holding capacity. Depth toSoil Drainage Class:
textures.
moderately well and well drained soils with moderately coarse
Class B - Moderate infiltration rates. Deep and moderately deep,Hydrologic Group:
sandy clay loamSoil Surface Texture:
CECIL Soil Component Name:
The following information is based on Soil Conservation Service STATSGO data.
in a landscape. Soil maps for STATSGO are compiled by generalizing more detailed (SSURGO) soil survey maps.
for privately owned lands in the United States. A soil map in a soil survey is a representation of soil patterns
Survey (NCSS) and is responsible for collecting, storing, maintaining and distributing soil survey information
The U.S. Department of Agriculture’s (USDA) Soil Conservation Service (SCS) leads the National Cooperative Soil
DOMINANT SOIL COMPOSITION IN GENERAL AREA OF TARGET PROPERTY
Map, USGS Digital Data Series DDS - 11 (1994).
of the Conterminous U.S. at 1:2,500,000 Scale - a digital representation of the 1974 P.B. King and H.M. Beikman
Geologic Age and Rock Stratigraphic Unit Source: P.G. Schruben, R.E. Arndt and W.J. Bawiec, Geology
ROCK STRATIGRAPHIC UNIT GEOLOGIC AGE IDENTIFICATION
Plutonic and Intrusive RocksCategory:PaleozoicEra:
OrdovianSystem:
Lower Paleozoic granitic rocksSeries:
Pzg1Code: (decoded above as Era, System & Series)
at which contaminant migration may be occurring.
Geologic information can be used by the environmental professional in forming an opinion about the relative speed
GEOLOGIC INFORMATION IN GENERAL AREA OF TARGET PROPERTY
move more quickly through sandy-gravelly types of soils than silty-clayey types of soils.
characteristics data collected on nearby properties and regional soil information. In general, contaminant plumes
to rely on other sources of information, including geologic age identification, rock stratigraphic unit and soil
using site specific geologic and soil strata data. If such data are not reasonably ascertainable, it may be necessary
Groundwater flow velocity information for a particular site is best determined by a qualified environmental professional
GROUNDWATER FLOW VELOCITY INFORMATION
®GEOCHECK - PHYSICAL SETTING SOURCE SUMMARY®
TC4073890.1s Page 5
sandy clay loam
unweathered bedrock
fine sandy loam
weathered bedrock
silty clay loamDeeper Soil Types:
loam
very channery - silt loam
clay
silty clay loam
silt loam
sandy clayShallow Soil Types:
gravelly - sandy loam
very channery - silt loam
silt loam
clay loam
loam
sandy loamSurficial Soil Types:
gravelly - sandy loam
very channery - silt loam
silt loam
clay loam
loam
sandy loamSoil Surface Textures:
appear within the general area of target property.
Based on Soil Conservation Service STATSGO data, the following additional subordinant soil types may
OTHER SOIL TYPES IN AREA
Min: 0.00
Max: 0.00
Min: 0.00
Max: 0.00Not reportedNot reportedvariable75 inches50 inches 4
Min: 4.50
Max: 5.50
Min: 0.60
Max: 2.00
silt.
more), Elastic
limit 50% or
Clays (liquid
SOILS, Silts and
FINE-GRAINED
Soils.
200), Clayey
passing No.
than 35 pct.
Materials (more
Silt-Clayclay50 inches11 inches 3
Min: 4.50
Max: 5.50
Min: 0.60
Max: 2.00
Silty Sand.
Sands with fines,
SOILS, Sands,
COARSE-GRAINED
Soils.
200), Silty
passing No.
than 35 pct.
Materials (more
Silt-Claysandy clay loam11 inches 7 inches 2
Min: 4.50
Max: 6.50
Min: 0.60
Max: 2.00
Silty Sand.
Sands with fines,
SOILS, Sands,
COARSE-GRAINED
Soils.
200), Silty
passing No.
than 35 pct.
Materials (more
Silt-Claysandy clay loam 7 inches 0 inches 1
Soil Layer Information
Boundary Classification
Permeability
Rate (in/hr)
Layer Upper Lower Soil Texture Class AASHTO Group Unified Soil Soil Reaction
(pH)
®GEOCHECK - PHYSICAL SETTING SOURCE SUMMARY®
TC4073890.1s Page 6
No Wells Found
STATE DATABASE WELL INFORMATION
LOCATION
FROM TPWELL IDMAP ID
Note: PWS System location is not always the same as well location.
1/4 - 1/2 Mile SSWNC0136706 1
FEDERAL FRDS PUBLIC WATER SUPPLY SYSTEM INFORMATION
LOCATION
FROM TPWELL IDMAP ID
1/2 - 1 Mile WSWUSGS40000886687 3
1/2 - 1 Mile SWUSGS40000886680 2
FEDERAL USGS WELL INFORMATION
LOCATION
FROM TPWELL IDMAP ID
1.000State Database
1.000Federal FRDS PWS
1.000Federal USGS
WELL SEARCH DISTANCE INFORMATION
SEARCH DISTANCE (miles)DATABASE
opinion about the impact of contaminant migration on nearby drinking water wells.
professional in assessing sources that may impact ground water flow direction, and in forming an
EDR Local/Regional Water Agency records provide water well information to assist the environmental
LOCAL / REGIONAL WATER AGENCY RECORDS
®GEOCHECK - PHYSICAL SETTING SOURCE SUMMARY®
EDR Inc.EDR Inc.EDR Inc.EDR Inc.EDR Inc.EDR Inc.EDR Inc.EDR Inc.EDR Inc.EDR Inc.EDR Inc.EDR Inc.EDR Inc.EDR Inc.EDR Inc.EDR Inc.EDR Inc.EDR Inc.EDR Inc.EDR Inc.EDR Inc.EDR Inc.EDR Inc.EDR Inc.EDR Inc.EDR Inc.EDR Inc.EDR Inc.EDR Inc.EDR Inc.EDR Inc.EDR Inc.EDR Inc.EDR Inc.EDR Inc.EDR Inc.EDR Inc.EDR Inc.EDR Inc.EDR Inc.6068076
0
7206 8076072
0
7 207206 40
6406 8 0
7 20 6 40760
7 20800720720
68 0
6
8
0
6
80
68 0 6806806 807
7 20
7 2 0
7 2 0
76 0 7 2072 0 720 720680 68 0 680
68 0
6 8 0
7 6 0720
72 0 760
7 6 0
7 60
720
8 0 0680
720720720
7 607 2 0
640720720720720720720
0 720
680
68068
0
680640680
680
680
7206406807 20
720
7
207207 60720
7607607
2
0
76 0
7 6 0
7207 60
720760
760
7207 6 0
760720 760
680
7207207 20720
7 2 0
720680
77207207
2
0
7 2 0
720680720 720720760720760
760
72068068 0680
7 2 0
6 80
640680680
7 207 207 2 0
72 0
72 00
6 80680 680680680 6 8 0 6
8
0680680680680680
6
8
0
680680
6800
680
6 8 0
6
8
0
6 8 0680
NC
TC4073890.1s Page 8
Not ReportedSourcemap scale:-80.9747968Longitude:
35.3587489Latitude:Not ReportedContrib drainagearea units:
Not ReportedContrib drainagearea:Not ReportedDrainagearea Units:
Not ReportedDrainagearea value:Not ReportedHuc code:
Not ReportedMonloc desc:
WellMonloc type:
GS-001Monloc name:
USGS-352131080583001Monloc Identifier:
USGS North Carolina Water Science CenterFormal name:
USGS-NCOrg. Identifier:
2
SW
1/2 - 1 Mile
Higher
USGS40000886680FED USGS
State Public Notif RequestedEnf. Action:2000-02-04Enforcement Date:
0003296Violation ID:
1999-10-01 - 1999-12-31Compliance Period:
COLIFORM (TCR)Contaminant:
Monitoring, Routine Major (TCR)Violation Type:
DUKE POWER-RIVERBEND STEAMSystem Name:
State Formal NOV IssuedEnf. Action:2000-02-04Enforcement Date:
0003296Violation ID:
1999-10-01 - 1999-12-31Compliance Period:
COLIFORM (TCR)Contaminant:
Monitoring, Routine Major (TCR)Violation Type:
DUKE POWER-RIVERBEND STEAMSystem Name:
ENFORCEMENT INFORMATION:
Violations information not reported.
00000026Population:TreatedTreatment Class:
Not ReportedCity Served:
080 58 00Facility Longitude:35 21 40Facility Latitude:
DUKE POWER STEAM PROD DEPT
System Owner/Responsible PartyAddressee / Facility:
MT HOLLY, NC 28120
PO BOX 367 ATN W M CAVIN
L G DUCKWORTH MAST MECH
System Owner/Responsible PartyAddressee / Facility:
28120
DUKE POWER-RIVERBEND STEAM STAPWS Name:
Not ReportedDate Deactivated:7706Date Initiated:
NC0136706PWS ID:
1
SSW
1/4 - 1/2 Mile
Higher
NC0136706FRDS PWS
Map ID
Direction
Distance
Elevation EDR ID NumberDatabase
®GEOCHECK - PHYSICAL SETTING SOURCE MAP FINDINGS®
TC4073890.1s Page 9
Ground-water levels, Number of Measurements: 0
Not ReportedWellholedepth units:
Not ReportedWellholedepth:ftWelldepth units:
305Welldepth:Not ReportedConstruction date:
Not ReportedAquifer type:
Felsic Metaigneous RockFormation type:
Piedmont and Blue Ridge crystalline-rock aquifersAquifername:
USCountrycode:Not ReportedVert coord refsys:
Not ReportedVertcollection method:
Not ReportedVert accmeasure units:
Not ReportedVertacc measure val:Not ReportedVert measure units:
Not ReportedVert measure val:NAD83Horiz coord refsys:
Interpolated from mapHoriz Collection method:
secondsHoriz Acc measure units:1Horiz Acc measure:
Not ReportedSourcemap scale:-80.9767413Longitude:
35.3593044Latitude:Not ReportedContrib drainagearea units:
Not ReportedContrib drainagearea:Not ReportedDrainagearea Units:
Not ReportedDrainagearea value:Not ReportedHuc code:
Not ReportedMonloc desc:
WellMonloc type:
GS-003Monloc name:
USGS-352133080583701Monloc Identifier:
USGS North Carolina Water Science CenterFormal name:
USGS-NCOrg. Identifier:
3
WSW
1/2 - 1 Mile
Lower
USGS40000886687FED USGS
Ground-water levels, Number of Measurements: 0
Not ReportedWellholedepth units:
Not ReportedWellholedepth:ftWelldepth units:
437.5Welldepth:Not ReportedConstruction date:
Not ReportedAquifer type:
Felsic Metaigneous RockFormation type:
Piedmont and Blue Ridge crystalline-rock aquifersAquifername:
USCountrycode:Not ReportedVert coord refsys:
Not ReportedVertcollection method:
Not ReportedVert accmeasure units:
Not ReportedVertacc measure val:Not ReportedVert measure units:
Not ReportedVert measure val:NAD83Horiz coord refsys:
Interpolated from mapHoriz Collection method:
secondsHoriz Acc measure units:1Horiz Acc measure:
®GEOCHECK - PHYSICAL SETTING SOURCE MAP FINDINGS®
TC4073890.1s Page 10
Not ReportedNot ReportedNot ReportedNot ReportedBasement
Not ReportedNot ReportedNot ReportedNot ReportedLiving Area - 2nd Floor
0%0%100%0.150 pCi/LLiving Area - 1st Floor
% >20 pCi/L% 4-20 pCi/L% <4 pCi/LAverage ActivityArea
Number of sites tested: 8
Federal Area Radon Information for Zip Code: 28120
: Zone 3 indoor average level < 2 pCi/L.
: Zone 2 indoor average level >= 2 pCi/L and <= 4 pCi/L.
Note: Zone 1 indoor average level > 4 pCi/L.
Federal EPA Radon Zone for GASTON County: 2
AREA RADON INFORMATION
®GEOCHECK - PHYSICAL SETTING SOURCE MAP FINDINGS
RADON
®
TOPOGRAPHIC INFORMATION
USGS 7.5’ Digital Elevation Model (DEM)
Source: United States Geologic Survey
EDR acquired the USGS 7.5’ Digital Elevation Model in 2002 and updated it in 2006. The 7.5 minute DEM corresponds
to the USGS 1:24,000- and 1:25,000-scale topographic quadrangle maps. The DEM provides elevation data
with consistent elevation units and projection.
HYDROLOGIC INFORMATION
Flood Zone Data: This data, available in select counties across the country, was obtained by EDR in 2003 & 2011 from the Federal
Emergency Management Agency (FEMA). Data depicts 100-year and 500-year flood zones as defined by FEMA.
NWI: National Wetlands Inventory. This data, available in select counties across the country, was obtained by EDR
in 2002, 2005 and 2010 from the U.S. Fish and Wildlife Service.
State Wetlands Data: Wetlands Inventory
Source: Department of Environment & Natural Resources
Telephone: [phone]
HYDROGEOLOGIC INFORMATION
AQUIFLOW Information SystemR
Source: EDR proprietary database of groundwater flow information
EDR has developed the AQUIFLOW Information System (AIS) to provide data on the general direction of groundwater
flow at specific points. EDR has reviewed reports submitted to regulatory authorities at select sites and has
extracted the date of the report, hydrogeologically determined groundwater flow direction and depth to water table
information.
GEOLOGIC INFORMATION
Geologic Age and Rock Stratigraphic Unit
Source: P.G. Schruben, R.E. Arndt and W.J. Bawiec, Geology of the Conterminous U.S. at 1:2,500,000 Scale - A digital
representation of the 1974 P.B. King and H.M. Beikman Map, USGS Digital Data Series DDS - 11 (1994).
STATSGO: State Soil Geographic Database
Source: Department of Agriculture, Natural Resources Conservation Services
The U.S. Department of Agriculture’s (USDA) Natural Resources Conservation Service (NRCS) leads the national
Conservation Soil Survey (NCSS) and is responsible for collecting, storing, maintaining and distributing soil
survey information for privately owned lands in the United States. A soil map in a soil survey is a representation
of soil patterns in a landscape. Soil maps for STATSGO are compiled by generalizing more detailed (SSURGO)
soil survey maps.
SSURGO: Soil Survey Geographic Database
Source: Department of Agriculture, Natural Resources Conservation Services (NRCS)
Telephone: [phone]
SSURGO is the most detailed level of mapping done by the Natural Resources Conservation Services, mapping
scales generally range from 1:12,000 to 1:63,360. Field mapping methods using national standards are used to
construct the soil maps in the Soil Survey Geographic (SSURGO) database. SSURGO digitizing duplicates the
original soil survey maps. This level of mapping is designed for use by landowners, townships and county
natural resource planning and management.
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PHYSICAL SETTING SOURCE RECORDS SEARCHED
LOCAL / REGIONAL WATER AGENCY RECORDS
FEDERAL WATER WELLS
PWS: Public Water Systems
Source: EPA/Office of Drinking Water
Telephone: [phone]
Public Water System data from the Federal Reporting Data System. A PWS is any water system which provides water to at
least 25 people for at least 60 days annually. PWSs provide water from wells, rivers and other sources.
PWS ENF: Public Water Systems Violation and Enforcement Data
Source: EPA/Office of Drinking Water
Telephone: [phone]
Violation and Enforcement data for Public Water Systems from the Safe Drinking Water Information System (SDWIS) after
August 1995. Prior to August 1995, the data came from the Federal Reporting Data System (FRDS).
USGS Water Wells: USGS National Water Inventory System (NWIS)
This database contains descriptive information on sites where the USGS collects or has collected data on surface
water and/or groundwater. The groundwater data includes information on wells, springs, and other sources of groundwater.
STATE RECORDS
North Carolina Public Water Supply Wells
Source: Department of Environmental Health
Telephone: [phone]
OTHER STATE DATABASE INFORMATION
NC Natural Areas: Significant Natural Heritage Areas
Source: Center for Geographic Information and Analysis
Telephone: [phone]
A polygon converage identifying sites (terrestrial or aquatic that have particular biodiversity significance.
A site’s significance may be due to the presenceof rare species, rare or hight quality natural communities, or
other important ecological features.
NC Game Lands: Wildlife Resources Commission Game Lands
Source: Center for Geographic Information and Analysis
Telephone: [phone]
All publicly owned game lands managed by the North Carolina Wildlife Resources Commission and as listed in Hunting
and Fishing Maps.
NC Natural Heritage Sites: Natural Heritage Element Occurrence Sites
Source: Center for Geographic Information and Analysis
Telephone: [phone]
A point coverage identifying locations of rare and endangered species, occurrences of exemplary or unique natural
ecosystems (terrestrial or aquatic), and special animal habitats (e.g., colonial waterbird nesting sites).
RADON
State Database: NC Radon
Source: Department of Environment & Natural Resources
Telephone: [phone]
Radon Statistical and Non Statiscal Data
Area Radon Information
Source: USGS
Telephone: [phone]
The National Radon Database has been developed by the U.S. Environmental Protection Agency
(USEPA) and is a compilation of the EPA/State Residential Radon Survey and the National Residential Radon Survey.
The study covers the years 1986 - 1992. Where necessary data has been supplemented by information collected at
private sources such as universities and research institutions.
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PHYSICAL SETTING SOURCE RECORDS SEARCHED
EPA Radon Zones
Source: EPA
Telephone: [phone]
Sections 307 & 309 of IRAA directed EPA to list and identify areas of U.S. with the potential for elevated indoor
radon levels.
OTHER
Airport Landing Facilities: Private and public use landing facilities
Source: Federal Aviation Administration, 800-457-6656
Epicenters: World earthquake epicenters, Richter 5 or greater
Source: Department of Commerce, National Oceanic and Atmospheric Administration
Earthquake Fault Lines: The fault lines displayed on EDR’s Topographic map are digitized quaternary faultlines, prepared
in 1975 by the United State Geological Survey
STREET AND ADDRESS INFORMATION
© 2010 Tele Atlas North America, Inc. All rights reserved. This material is proprietary and the subject of copyright protection
and other intellectual property rights owned by or licensed to Tele Atlas North America, Inc. The use of this material is subject
to the terms of a license agreement. You will be held liable for any unauthorized copying or disclosure of this material.
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PHYSICAL SETTING SOURCE RECORDS SEARCHED