HomeMy WebLinkAboutAsheville Plan for Identification of New DischargesPlan for Identification of New Discharges September 2014
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TABLE OF CONTENTS
SECTION PAGE
1.0 Introduction ..................................................................................................................... 1
2.0 Site Description ............................................................................................................... 3
2.1 Plant Description ........................................................................................................ 3
2.2 Ash Basin Description ............................................................................................... 3
3.0 Section Site Geology and Hydrogeology ................................................................... 5
3.1 Site Geologic/Soil Framework .................................................................................. 5
3.2 Site Hydrogeologic Framework ............................................................................... 5
4.0 Identification of New Discharges ................................................................................ 7
4.1 Purpose of Inspection ................................................................................................ 7
4.2 Seepage ........................................................................................................................ 7
4.3 Area To Be Inspected for New Discharges ............................................................. 7
4.4 Inspection Procedure ................................................................................................. 7
5.0 References ......................................................................................................................... 9
List of Figures
Figure 1 – Site Location Map
Figure 2 – Areas To Be Inspected For Seeps
List of Appendices
Appendix A - Inspection for Identification of New Discharges
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1.0 INTRODUCTION
The purpose of this document is to address the requirements of North Carolina General
Statute (GS)130A-309.210 (d) Identification and assessment of discharges; correction of
unpermitted discharges, as modified by North Carolina Senate Bill 729, for the Asheville
Steam Electric Plant ash basin operated under National Pollution Discharge Elimination
System (NPDES) Permit NC0000396.
The following requirements are contained in General statue 130A-309.210:
d) Identification of New Discharges. – No later than October 1, 2014, the owner of a coal
combustion residuals surface impoundment shall submit a proposed Plan for the
Identification of New Discharges to the Department for its review and approval as
provided in this subsection.
(1) The proposed Plan for the Identification of New Discharges shall include, at a
minimum, all of the following:
a. A procedure for routine inspection of the coal combustion residuals surface
impoundment to identify indicators of potential new discharges, including
toe drain outfalls, seeps, and weeps.
b. A procedure for determining whether a new discharge is actually present.
c. A procedure for notifying the Department when a new discharge is
confirmed.
d. Any other information related to the identification of new discharges
required by the Department.
(2) The Department shall approve the Plan for the Identification of New
Discharges if it determines that the Plan complies with the requirements of this
subsection and will be sufficient to protect public health, safety, and welfare; the
environment; and natural resources.
(3) No later than 30 days from the approval of the Plan for the Identification of New
Discharges, the owner shall begin implementation of the Plan in accordance
with the Plan.
The North Carolina Senate Bill 729 establishes the submittal date of this Plan for
Identification of New Discharges no later than October 1, 2014.
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This bill also modified GS 130A to establish the following submittals that are related to
this Plan. GS130A-309.210(a) was modified to require:
(2) No later than December 31, 2014, the owner of a coal combustion residuals surface
impoundment shall submit a topographic map that identifies the location of all (i) outfalls
from engineered channels designed or improved for the purpose of collecting water from the
toe of the impoundment and (ii) seeps and weeps discharging from the impoundment that are
not captured by engineered channels designed or improved for the purpose of collecting
water from the toe of the impoundment to the Department. The topographic map shall comply
with all of the following:
a. Be at a scale as required by the Department.
b. Specify the latitude and longitude of each toe drain outfall, seep, and weep.
c. Specify whether the discharge from each toe drain outfall, seep, and weep
is continuous or intermittent.
d. Provide an average flow measurement of the discharge from each toe drain
outfall, seep, and weep including a description of the method used to
measure average flow.
e. Specify whether the discharge from each toe drain outfall, seep, and weep
identified reaches the surface waters of the State. If the discharge from a
toe drain outfall, seep, or weep reaches the surface waters of the State, the
map shall specify the latitude and longitude of where the discharge reaches
the surface waters of the State.
f. Include any other information related to the topographic map required by
the Department.
The inspection procedures presented in this plan, developed to satisfy the requirements
of GS130A-309.210(d), will be used as the basis for developing the topographic map
required by GS130A-309.210(a)(2).
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2.0 SITE DESCRIPTION
2.1 Plant Description
Duke Energy Progress, Inc. (Duke Energy) owns and operates the Asheville Plant which
began commercial operation in the 1960s, with additions in the 1990s and around 2000,
and consists of two coal-fired units that primarily use bituminous coal. Additionally,
the Plant also has two combustion turbines. Ash generated from coal combustion has
been stored on-site in the ash basins and is also used as beneficial fill at the nearby
Asheville Airport. The on-site ash basins are encircled within the waste boundary and
500-foot compliance boundary shown on Figure 1.
Lake Julian was built for cooling water by damming the flow of Powell Creek on the
north side of the plant. A large portion of Lake Julian borders the east side of the plant
site. Surface water from the French Broad River is also pumped into Lake Julian as a
supplemental water supply. The water from the French Broad River enters a stilling
area of the lake on the north side of the plant. Heated water is discharged back into
Lake Julian to the east of the plant. The French Broad River borders the west side of the
property and flows south to north. Powell Creek also flows south to north prior to
formation of Lake Julian. Powell Creek flows east to west from the Lake Julian Dam to
the French Broad River.
2.2 Ash Basin Description
The plant and ash basins are located on the east side of I-26 and the French Broad River.
The current configuration of the ash basins is shown on Figure 2. The ash management
area consists of:
The original 1964 ash basin, built during plant construction and expanded in the
1970s, is now overlain with wastewater treatment wetlands. The treatment
wetlands basins are lined.
The 1964 ash basin was replaced with a second ash basin, built in approximately
1982, located to the south of the 1964 ash basin.
The 1982 ash basin is being dewatered and excavated. The ash is being
transported to the Asheville Airport for structural fill. New ash is being
generated daily and is being dewatered in concrete lined basins located on a
portion of the 1964 ash basin.
The ash basin system is an integral part of the plant’s wastewater treatment system
which receives inflows from ash transport water, coal pile runoff, storm water runoff,
and various low volume wastes. The treated wastewater is permitted to discharge to
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the French Broad River via permitted Outfall 001. The 500 foot compliance boundary
circles the ash management area (Figure 2).
The discharge from the ash basins are permitted by the North Carolina Department of
Environment and Natural Resources (NCDENR) Division of Water Resources (DWR)
under the National Pollution Discharge Elimination System (NPDES) Permit
NC0000396.
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3.0 SITE GEOLOGY AND HYDROGEOLOGY
3.1 Site Geologic/Soil Framework
The Asheville Plant is located in the Piedmont Mountain region of North Carolina as
described by LeGrand (2004). The geology across the site varies from mica gneiss and
garnet mica schist in the upland areas (east of I-26) to alluvium along the French Broad
River floodplain (west of I-26).
In general, the regional geology consists of overburden, also referred to as regolith, and
metamorphic bedrock. In stream valleys, fluvial deposits, also referred to as alluvium,
overlie the bedrock. The metamorphic rock, primarily schist and gneiss, tends to be
exposed on the ground surface along topographic ridges, road cuts, and in stream or
river valleys. Where the metamorphic bedrock has been weathered into unconsolidated
material, silt, sand and clay are found overlying the bedrock. The two layers,
regolith/saprolite or alluvium, and consolidated bedrock form the basic framework of
the groundwater system. The transition zone between the regolith and consolidated
bedrock can be a significant hydrogeologic feature in the system.
The regolith tends to be composed of a shallow soil zone where the relict structure of
the original bedrock material is no longer present. The soil zone transitions downward
into saprolite, which is still unconsolidated material, but has the visual texture of the
parent bedrock. Saprolite is generally composed of silt, sand, and clay with a porosity
ranging from 35 to 55 percent, making it a storage reservoir for groundwater with good
natural attenuation characteristics. Where the thickness of saprolite is thin, or it is not
present, the saturated zone may be entirely in fractured bedrock. The consolidated
nature of the bedrock limits the presence and transport of groundwater to fractures
interconnected with the ground surface or the overlying regolith. In areas where the
saprolite to competent bedrock is gradual, the slightly weathered rock referred to as the
'transition zone' can be a significant zone of groundwater transport.
3.2 Site Hydrogeologic Framework
The geology at the depth of the water table (the screened interval for most of the site
compliance boundary wells) varies across the site from being within the regolith (within
the saprolite), the transition zone between saprolite and competent bedrock, within the
upper bedrock, or within floodplain alluvial deposits.
The topography of the water table (the depth to the saturated aquifer) tends to mirror
the ground surface topography. Topographic ridges and stream valleys, or topographic
lows between ridges create groundwater divides. The groundwater flow will follow the
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surface topography until the water table intersects the ground surface in a spring, seep
or stream.
As discussed by LeGrand (2004), the French Broad River and its tributaries are
groundwater discharge zones for the saprolite and bedrock aquifer at the site. The
French Broad River creates a hydrogeologic boundary to the west of the plant site. The
Powell Creek drainage feature creates a hydrogeologic boundary to the north side of the
site. The unnamed tributary located along the southern property line creates a
hydrogeologic boundary to the south of the site. Lake Julian is located upgradient of
the ash management area and it, along with the Powell Creek drainage basin, form the
eastern hydraulic boundary of the site.
As further discussed by LeGrand (2004), groundwater moves continuously toward
streams where it discharges in small springs or seeps in draws or topographic
depressions. The path of groundwater is restricted by topography. Groundwater rarely
passes beneath a perennial stream to another groundwater flow system. Thus the
concept of local slope aquifer systems, or compartments, applies to the regional
geologic setting of the site. The high crests of the water table (recharge zones) represent
natural groundwater divides as do the low lying stream discharge zones. These
localized hydrogeologic flow system compartments tend to keep potential contaminant
migration within the flow compartment from which it originates. It is possible,
although unusual, that isolated bedrock fractures that receive recharge from one slope
aquifer compartment could extend beneath a boundary stream and intercept a fracture
serving a well in a neighboring slope aquifer compartment. This can occur when a
pumping well pulls the groundwater beyond its natural discharge zone.
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4.0 IDENTIFICATION OF NEW DISCHARGES
4.1 Purpose of Inspection
The purpose of the inspection is to identify new discharges and indicators of potential
new discharges, including toe drain outfalls, seeps, and weeps associated with the coal
combustion residuals surface impoundment (ash basins).
4.2 Seepage
Seepage is considered to be the movement of wastewater from the ash basin through
the ash basin embankment, the embankment foundation, the embankment abutments,
or through residual material in areas adjacent to the ash basin. A seep is defined in this
document as an expression of seepage at the ground surface. A weep is understood to
have the same meaning as a seep.
Indicators of seepage include areas where water is observed on the ground surface
and/or where vegetation suggests the presence of seepage. Seepage can emerge
anywhere on the downstream face, beyond the toe, or on the downstream abutments at
elevations below normal pool. Seepage may vary in appearance from a "soft," wet area
to a flowing "spring." Seepage may show up first as only an area where the vegetation
is lusher and darker green than surrounding vegetation. Cattails, reeds, mosses, and
other marsh vegetation often become established in a seepage area (NCDENR, 1985).
However, in many instances, indicators of seeps do not necessarily indicate the
presence of seeps.
4.3 Area To Be Inspected for New Discharges
The areas to be inspected are the areas of the site where water contained in or
percolating through the ash basins might infiltrate into the underlying residual material
and be expressed as seepage. The extent of the areas to be inspected was determined
based on the generalized LeGrand conceptual model and the concept of the slope-
aquifer system and the site topography. In this generalization, flow of water from the
ash basins would be expected to be located within the slope-aquifer compartment and
to be below the dam elevations. The areas to be inspected are shown on Figure 2.
4.4 Inspection Procedure
The inspection procedure for identification of new discharges and indicators of
potential new discharges associated with the Asheville ash basin system is provided in
Appendix A. In addition to the specific requirements for the inspection, Appendix A
also provides the general requirements, the frequency of inspections, documentation
requirements, and provides a decision flow chart for determining if the potential new
discharge is associated with an ash basin.
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5.0 REFERENCES
LeGrand, Harry E., Sr., 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.
NCDENR, “Dam Operation, Maintenance, and Inspection Manual”, 1985 (Revised
2007).
FIGURES
PROJECT MANAGER:
LAYOUT:
DRAWN BY:
KATHY WEBB
DATE:S. ARLEDGE
FIG 1 (USGS SITE LOCATION)
2014-09-26
FIGURE 1
SITE LOCATION MAP
DUKE ENERGY PROGRESS
ASHEVILLE STEAM ELECTRIC PLANT
200 CP&L DRIVE
ARDEN, NORTH CAROLINA
SKYLAND NC QUADRANGLE
2000
GRAPHIC SCALE
1000
IN FEET
10000CONTOUR INTERVAL:
MAP DATE:
20 FT
1991
DUKE ENERGY PROGRESS
BUNCOMBE COUNTY
148 RIVER STREET, SUITE 220
GREENVILLE, SOUTH CAROLINA
PHONE 864-421-9999
www.synterracorp.com
USGS TOPOGRAPHIC MAP OBTAINED FROM GEOSPATIAL
DATA GATEWAY AT http://datagateway.nrcs.usda.gov/
SOURCE:
PROPERTY BOUNDARY
500' COMPLIANCE
BOUNDARY
WASTE
BOUNDARY
I
-26
LAKE JULIAN
P
OW
E
L
L
C
R
E
E
KFRENCH BROAD RIVER
2500 250 500GRAPHIC SCALEIN FEETFIG 2 (SEEP INSPECTION AREA2014-09-26J. WYLIES. ARLEDGEPROJECT MANAGER:LAYOUT NAME:DRAWN BY:CHECKED BY:K. WEBBDATE:DATE:FIGURE 2AREAS TO BE INSPECTEDFOR SEEPSwww.synterracorp.com148 River Street, Suite 220Greenville, South Carolina 29601864-421-9999ASHEVILLE STEAM ELECTRIC PLANT200 CP & L DRIVEARDEN, NORTH CAROLINA2014-09-26LEGEND500 ft COMPLIANCE BOUNDARYDUKE ENERGY PROGRESS ASHEVILLEPLANTWASTE BOUNDARYBOUNDARY OF AREA TO BEINSPECTED FOR SEEPSFLOW DIRECTIONNPDES OUTFALL LOCATIONASH BASIN COMPLIANCE GROUNDWATERMONITORING WELL2007 LiDAR CONTOUR MAJOR2007 LiDAR CONTOUR MINOR2220INTERSTATE 26TO ASHEVILLEINTERSTATE 26TO HENDERSONVILLEFRENCH BROAD RIVERLAKE JULIANLAKE COMAFRENCH BROAD RIVERUNNAMED TRIBUTARYFLOWFLOWRAW WATER INTAKESOURCES:1. 2012 AERIAL PHOTOGRAPH OBTAINED FROM NRCSGEOSPATIAL DATA GATEWAY AThttp://datagateway.nrcs.usda.gov/2. 2014 AERIAL PHOTOGRAPH OBTAINED FROM WSP FLOWNON APRIL 17, 2014.3. PARCEL BOUNDARY WAS OBTAINED FROM BUNCOMBECOUNTY GIS DATA AThttp://gis.buncombecounty.org/buncomap/Map_All.html4. DRAWING HAS BEEN SET WITH A PROJECTION OF NORTHCAROLINA STATE PLANE COORDINATE SYSTEM FIPS 3200(NAD 83).5. 2ft CONTOUR INTERVALS FROM NCDOT LiDAR DATED2007https://connect.ncdot.gov/resources/gis/pages/cont-elev_v2.aspx6. COMPLIANCE MONITORING WELL LOCATIONS ANDWASTE BOUNDARY FROM FCA OF NC, SURVEY DATEDMARCH 2009. COMPLIANCE WELLS CB-3R, CB-9 AND SG-1SURVEYED BY FCA OF NC, SURVEY DATED 2012-11-28.NOTE:1. CONTOUR LINES ARE USED FOR REPRESENTATIVEPURPOSES ONLY AND ARE NOT TO BE USED FOR DESIGNOR CONSTRUCTION PURPOSES.LAKE JULIANCB-9CB-9CB-8CB-7CB-6CB-4BCB-4CB-5CB-3RCB-2CB-1GW-1
APPENDIX A
Inspection for Identification of New
Discharges
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1. Purpose of Inspection
The purpose of the inspection is to identify new discharges and indicators of potential new
discharges, including toe drain outfalls, seeps, and weeps that arise after the initial submittal of
maps required by North Carolina General Statute 130A‐309.210(a)(2)(ii). Seepage is considered
to be the movement of wastewater from the ash basin through the ash basin embankment, the
embankment foundation, the embankment abutments, or through residual material in areas
adjacent to the ash basin. Therefore, a seep is defined in this document as an expression or
occurrence of potential wastewater at the ground surface. A weep is understood to have the
same meaning as a seep. If new discharges or indicators of potential new discharges are
identified, the decision flow chart (see Figure A‐1) will be used to determine if the potential new
discharge is from the ash basin and if notification to the North Carolina Department of
Environment and Natural Resources (NCDENR) Division of Water Resources (DWR) is
required.
2. General Inspection Requirements
2.1. Inspections are to be performed on areas that are below the ash basin full pond
elevation and within the area shown on Figure A‐2. The scope of the inspections
includes identification of seeps from residual ground and outfalls from engineered
channels.
2.2. If required, a larger scale figure showing the locations of outfalls from engineered
channels will be developed. If a separate figure showing outfalls from engineered
channels is not developed, Figure A‐2 will be revised to show these features.
2.3. Inspections of areas on or adjacent to the ash basin embankments should be performed
within two months after mowing, if possible.
2.4. Inspections should not be performed if the following precipitation amounts have
occurred in the respective time period preceding the planned inspection:
2.4.1. Precipitation of 0.1 inches or greater within 72 hours, or
2.4.2. Precipitation of 0.5 inches or greater within 96 hours.
2.5. Record most recent ash basin water surface elevation.
2.6. Review previous inspections for new discharges prior to performing inspection.
2.7. Review the most recent previous dam inspections.
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2.8. Conduct an interview with the Site Environmental Coordinator prior to performing
inspection to inquire about possible changes to site conditions, such as pond elevations,
operations, additions or removal of wastewater discharges to the ash basin, changes to
site surface water drainage, etc.
3. Frequency of Inspections
Inspections will be performed on a semi‐annual basis during the first quarter of the year
(January to March representative of seasonal high precipitation and while vegetation is
dormant) and during the third quarter (July to September representative of seasonal low
precipitation and vegetative growth).
4. Qualifications
The inspections shall be performed under the direction of a qualified Professional Engineer or
Professional Geologist.
5. Documentation of Inspection
The inspection shall be documented by the individual performing the inspection. The report
should contain observations and descriptions of the seeps observed, changes in observations
compared to previous inspections, estimates of flows quantities, and photographs of seeps and
outfalls of engineered channels designed or improved for collecting water from the
impoundment. Photographs are to be numbered and captioned.
6. Initial Inspection
An initial inspection should be performed to identify features and document baseline
conditions including location, extent (i.e., dimensions of affected area), and flow. Seep locations
should be recorded using a Global Positioning System (GPS) device. Photographs should be
taken from vantage points that can be replicated during subsequent semi‐annual inspections.
7. Inspection For New Seeps at Outfalls From Engineered Outfalls
Inspect the outfalls from engineered channels designed and/or improved (such as through the
placement of rip‐rap) associated with the ash basin dikes to identify new seeps or indicators of
new seeps.
7.1. Inspect all outfalls from engineered channels designed and/or improved (such as
through the placement of rip‐rap).
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7.2. Document the condition of the outfall of the engineered channel with photographs.
Photographs are to be taken from a similar direction and scale as the original
photographs taken during the initial inspection.
7.3. Observe outfall for seepage and for indicators of seeps.
7.4. Compare current seepage location, extent, and flow to seepage photographs and
descriptions from previous inspections.
7.5. Record flow rate if measureable.
8. Inspection For New Seeps Not Captured by Engineered Channels
Inspect areas below the ash basin full pond elevation and within the boundary of the area to be
inspected as shown on Figure A‐2 to identify new seeps or indicators of new seeps. Inspect
topographic drainage features that potentially could contain new seeps that potentially
discharge from the ash basin. Requirements for documentation of the inspection are found in
Section 5.
8.1. Previously Identified Seeps
a) Inspect previously identified seep locations. Document the condition of the seeps
with a photograph. Photographs are to be taken from similar direction and at a
similar scale as the original photograph documenting the seep. Describe the
approximate dimensions and flow conditions of the seep.
b) If measureable, record flow.
c) Observe seep to determine if changes to location, extent, of flow are present.
Document changes to location, extent, and/or flow amount or pattern.
8.2. New Seep or Indicators of Seep
a) Mark the location of new seep or indicators of seep using a GPS device.
b) Document the condition of the seeps or indicators of seeps with a photograph.
c) Describe the approximate dimensions and flow conditions of the seep.
d) Map the location of new seep or indicator of seep using GPS coordinate points
collected during the site visit.
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e) If seep or indicator of seep was not caused by changes in surface water drainage and
if the location is below the ash basin pond elevation, utilize the decision flow chart to
determine if the seep represents a discharge from the ash basin and if notification to
DWR is required.
9. Update Maps Identifying Seeps
If new seeps are identified during the inspection, Figure A‐2 shall be updated to show the
location of the new seeps.
10. Decision Flow Chart
The decision flow chart developed to determine whether a new seep discharges from the ash
basin is found in Figure A‐1.
11. Procedure for Notifying NCDENR DWR If New Discharge Is Confirmed
If it is determined that a newly identified seep is present, Duke Energy will notify the DWR
regional office by mail within 14 days after the determination.
Figure A‐1 Decision Flow Chart for Determining If New Seep Represents Discharge From the Ash Basin LocationsDuke Energy Progress, North CarolinaIs new seep located below elevation of ash basin?New seep is not related to ash basinIs new seep located within the boundary of area to be inspected for seeps as shown on Figure A‐2?New seep is not hydraulically related to ash basinDoes new seep present concentrated flow that could be collected, measured and sampled?New seep presents diffuse flow conditions. Photograph, map location; add to seep location map, describe flow conditions, and approximate area of seepage. Collect water quality sample at seep and perform the following analyses:Field parameters: pH, specific conductance, temperature, etc. Constituent analyses: NPDES parameters, plus major cations and anionsCompare analytical results from seep to relevant ash basin and groundwater sampling results to determine if analytical results from new seep indicate discharge from the ash basinDo analytical results from new seep indicate discharge from ash basin?Prepare report documenting inspection and evaluation. Notify DWR that new seep identified and based on above evaluation, the new seep represents discharge from ash basin.Prepare report documenting inspection and evaluation. Notify DWR that new seep was identified; however new seep does not represent discharge from ash basin.Review previous seep inspection reportsPerform inspection for new seepsNoNoNoNoYesYesYesYesNotes:1. If no new seeps are identified, inspection will be documented however no notification to NCDENR DWR is required.2. If new seeps are identified that do not represent discharge from the ash basin during the same inspection that identifies new seeps that do represent a discharge from the ash basin, a single report will be submitted to NCDENRDWR.
2500 250 500GRAPHIC SCALEIN FEETFIG A-2 (SEEP INSPECTION AREA)2014-09-26J. WYLIES. ARLEDGEPROJECT MANAGER:LAYOUT NAME:DRAWN BY:CHECKED BY:K. WEBBDATE:DATE:FIGURE A-2AREAS TO BE INSPECTEDFOR SEEPSwww.synterracorp.com148 River Street, Suite 220Greenville, South Carolina 29601864-421-9999ASHEVILLE STEAM ELECTRIC PLANT200 CP & L DRIVEARDEN, NORTH CAROLINA2014-09-26LEGEND500 ft COMPLIANCE BOUNDARYDUKE ENERGY PROGRESS ASHEVILLEPLANTWASTE BOUNDARYBOUNDARY OF AREA TO BEINSPECTED FOR SEEPSFLOW DIRECTIONNPDES OUTFALL LOCATIONASH BASIN COMPLIANCE GROUNDWATERMONITORING WELL2007 LiDAR CONTOUR MAJOR2007 LiDAR CONTOUR MINOR2220INTERSTATE 26TO ASHEVILLEINTERSTATE 26TO HENDERSONVILLEFRENCH BROAD RIVERLAKE JULIANLAKE COMAFRENCH BROAD RIVERUNNAMED TRIBUTARYFLOWFLOWRAW WATER INTAKESOURCES:1. 2012 AERIAL PHOTOGRAPH OBTAINED FROM NRCSGEOSPATIAL DATA GATEWAY AThttp://datagateway.nrcs.usda.gov/2. 2014 AERIAL PHOTOGRAPH OBTAINED FROM WSP FLOWNON APRIL 17, 2014.3. PARCEL BOUNDARY WAS OBTAINED FROM BUNCOMBECOUNTY GIS DATA AThttp://gis.buncombecounty.org/buncomap/Map_All.html4. DRAWING HAS BEEN SET WITH A PROJECTION OF NORTHCAROLINA STATE PLANE COORDINATE SYSTEM FIPS 3200(NAD 83).5. 2ft CONTOUR INTERVALS FROM NCDOT LiDAR DATED2007https://connect.ncdot.gov/resources/gis/pages/cont-elev_v2.aspx6. COMPLIANCE MONITORING WELL LOCATIONS ANDWASTE BOUNDARY FROM FCA OF NC, SURVEY DATEDMARCH 2009. COMPLIANCE WELLS CB-3R, CB-9 AND SG-1SURVEYED BY FCA OF NC, SURVEY DATED 2012-11-28.NOTE:1. CONTOUR LINES ARE USED FOR REPRESENTATIVEPURPOSES ONLY AND ARE NOT TO BE USED FOR DESIGNOR CONSTRUCTION PURPOSES.LAKE JULIANCB-9CB-9CB-8CB-7CB-6CB-4BCB-4CB-5CB-3RCB-2CB-1GW-1