HomeMy WebLinkAboutNC0004979_Allen DAP_20141230
Allen Steam Station Ash Basin
Topographic Map and
Discharge Assessment Plan
NPDES Permit NC0004979
December 30, 2014
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Allen Steam Station Ash Basin
CONTENTS
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Contents
Page
Contents ...................................................................................................................................... i
Figures and Tables ..................................................................................................................... ii
Section 1 - Introduction .............................................................................................................. 1
Section 2 - Site Background ....................................................................................................... 3
2.1 Plant Description .................................................................................................. 3
2.2 Ash Basin Description .......................................................................................... 3
2.3 Site Geologic/Soil Framework .............................................................................. 3
2.4 Topographic Map and Identification of Discharges ............................................... 4
2.4.1 Engineered Drainage System for Earthen Dam ........................................ 5
2.4.2 Non-Engineered Seep Identification ......................................................... 5
Section 3 - Discharge Assessment Plan..................................................................................... 6
3.1 Purpose of Assessment ....................................................................................... 6
3.2 Assessment Procedure ........................................................................................ 6
3.2.1 General Assessment Requirements ......................................................... 6
3.2.2 Observation and Sampling ....................................................................... 7
3.2.3 Evaluation 9
3.2.4 Assessment Reporting ............................................................................. 9
Section 4 - References ..............................................................................................................10
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Allen Steam Station Ash Basin
FIGURES AND TABLES
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Figures and Tables
Figure 1 – Site Location Map
Figure 2 – Topographic Map
Table 1 – Seep and Associated Discharge Locations and Descriptions
Table 2 – Laboratory Analytical Methods
Table 3 – Allen Steam Station – Example of Surface Water/Seep Monitoring Flow and Analysis
Results Table
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Allen Steam Station Ash Basin
SECTION 1 - INTRODUCTION
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Section 1 - Introduction
The purpose of this document is to address the requirements of North Carolina General Statute
(GS)130A-309.210(a) topographic map and (b) Assessment of Discharges from Coal
Combustion Residuals Surface Impoundments to the Surface Waters of the State, as modified
by North Carolina Senate Bill 729, for the Allen Steam Station ash basin operated under
National Pollutant Discharge Elimination System (NPDES) Permit NC0004979.
The following requirements are contained in General Statute (GS) 130A-309.210(a):
(1) The owner of a coal combustion residuals surface impoundment shall identify all
discharges from the impoundment as provided in this subsection. The requirements for
identifying all discharges from an impoundment set out in this subsection are in addition
to any other requirements for identifying discharges applicable to the owners of coal
combustion residuals surface impoundments.
(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 following requirements are contained in General Statute (GS) 130A-309.210(b):
b) Assessment of Discharges from Coal Combustion Residuals Surface Impoundments to
the Surface Waters of the State. The owner of a coal combustion residuals surface
impoundment shall conduct an assessment of discharges from the coal combustion
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SECTION 1 - INTRODUCTION
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residuals surface impoundment to the surface waters of the State as provided in this
subsection. The requirements for assessment of discharges from the coal combustion
residuals surface impoundment to the surface waters of the State set out in this
subsection are in addition to any other requirements for the assessment of discharges
from coal combustion residuals surface impoundments to surface waters of the State
applicable to the owners of coal combustion residuals surface impoundments.
(1) No later than December 31, 2014, the owner of a coal combustion residuals surface
impoundment shall submit a proposed Discharge Assessment Plan to the
Department. The Discharge Assessment Plan shall include information sufficient to
allow the Department to determine whether any discharge, including a discharge
from a toe drain outfall, seep, or weep, has reached the surface waters of the State
and has caused a violation of surface water quality standards. The Discharge
Assessment Plan shall include, at a minimum, all of the following:
a. Upstream and downstream sampling locations within all channels that could
potentially carry a discharge.
b. A description of the surface water quality analyses that will be performed.
c. A sampling schedule, including frequency and duration of sampling activities.
d. Reporting requirements.
e. Any other information related to the identification of new discharges required by
the Department.
(2) The Department shall approve the Discharge Assessment Plan 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 Discharge Assessment Plan, the
owner shall begin implementation of the Plan in accordance with the Plan’s
schedule.
The North Carolina Senate Bill 729 establishes the submittal date of this topographic map and
Discharge Assessment Plan no later than December 31, 2014.
The topographic map, developed to satisfy the requirements of GS130A-309.210(a), was
utilized as the basis for developing the assessment procedures presented in this plan, required
by GS130A-309.210(b).
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Allen Steam Station Ash Basin
SECTION 2 - SITE BACKGROUND
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Section 2 - Site Background
2.1 Plant Description
Allen Steam Station is a five-unit, coal-fired, electric generating plant with a capacity of 1,140
megawatts located on the west bank of the Catawba River on Lake Wylie in Belmont, Gaston
County, North Carolina. The site is located east of South Point Road (NC 273) and the
surrounding area generally consists of residential properties, undeveloped land, and Lake Wylie
(Figure 1).
2.2 Ash Basin Description
Allen Steam Station’s ash basin consists of an active ash basin and an inactive ash basin. The
active ash basin was commissioned in 1973 and is currently in operation1. The inactive ash
basin is located to the north of the active ash basin and is not in operation. A large portion of the
area on top of the inactive ash basin is permitted as an industrial landfill by the NCDENR
Division of Waste Management (Permit No. 3612). The area contained within the ash basin
waste boundary is approximately 322 acres in area.
There are two earthen dikes impounding the active ash basin: the East Dike, located along the
west bank of Lake Wylie, and the North Dike, separating the active and inactive ash basins. The
surface area of the active ash basin is approximately 169 acres (Duke Energy, 2009) with an
operating pond elevation of approximately 633.5 feet. The full pond elevation of Lake Wylie is
approximately 568.7 feet.
The ash basin is operated as an integral part of the station’s wastewater treatment system,
which receives flows from the ash removal system, coal pile runoff, landfill leachate, flue-gas
desulfurization (FGD) wastewater, the station yard drain sump, and stormwater flows. Due to
variability in station operations and weather, the inflows to the ash basin are highly variable. The
inflows from the ash removal system and other plant discharges are discharged through sluice
lines to the ash basin. Prior to 2009, all of the fly ash produced was sluiced to the ash basin.
Since 2009, fly ash has been dry-handled and is infrequently sluiced to the ash basin. All of the
bottom ash produced by the station is sluiced to the ash basin.
Effluent from the ash basin is discharged from the discharge tower via a 42-inch-diameter
reinforced concrete pipe to Lake Wylie. The water surface elevation in the ash basin is
controlled by the use of stoplogs in the discharge tower.
2.3 Site Geologic/Soil Framework
Allen Steam Station 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).
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The topography of the Piedmont region is characterized by low, rounded hills and long, rolling,
northeast-southwest trending ridges (Heath, 1984). Stream valley to ridge relief in most areas
ranges from 75 to 200 feet. Along the Coastal Plain boundary, the Piedmont region rises from
an elevation of 300 feet above mean sea level to the base of the Blue Ridge Mountains at an
elevation of 1,500 feet (LeGrand 2004).
Charlotte terrane bedrock consists primarily 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 are 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).
Groundwater flow paths in the Piedmont are almost invariably restricted to the zone underlying
the topographic slope extending from a topographic divide to an adjacent stream. LeGrand
describes this as the local slope aquifer system. Under natural conditions, the general direction
of groundwater flow can be approximated from the surface topography (LeGrand 2004).
Groundwater recharge in the Piedmont is derived entirely from infiltration of local precipitation.
Groundwater recharge occurs in areas of higher topography (i.e., hilltops) and groundwater
discharge occurs in lowland areas bordering surface water bodies, marshes, and floodplains
(LeGrand 2004).
Allen’s ash basin is situated between the steam station to the north and surface water divides to
the west (along South Point Road) and south (along Reese Wilson Road), which both drop in
elevation to the east toward Lake Wylie. The surface water divide along South Point Road likely
functions as a groundwater divide. The topography at the site generally slopes downward from
that divide toward Lake Wylie. The entire Allen site is approximately 1,009 acres in area.
2.4 Topographic Map and Identification of Discharges
A topographic map is presented in Figure 2 to meet the requirements of GS 130A-309.210(a) in
the identification of outfalls from engineered channels, as well as seeps and weeps.
Seepage is the movement of wastewater from the ash basin through the ash basin
embankment, the embankment foundation, the embankment abutments, basin rim, through
residual material in areas adjacent to the ash basin. A seep is defined in this document as an
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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. However, in many instances, indicators of seeps do not
necessarily indicate the presence of seeps. Areas of apparent iron staining and/or excess iron
bacteria may also indicate the presence of a seep.
Locations of seepage at the ground surface adjacent to the ash basin have been identified and
are shown in Figure 2. These areas include the earthen embankments which impound the ash
basin as well as adjacent areas where water from the ash basin may have infiltrated into the
underlying residual materials and expressed as seepage.
2.4.1 Engineered Drainage System for Earthen Dam
Earth dams are subject to seepage through the embankment, foundation, and abutments.
Seepage control is necessary to prevent excessive uplift pressures, instability of the
downstream slope, piping through the embankment and/or foundation, and erosion of material
by migration into open joints in the foundation and abutments. The control of seepage is
performed by the use of engineered drains such as blanket drains, trench drains, and/or toe
drains. In certain cases, horizontal pipes may be installed into the embankment to collect and
control seepage. It is standard engineering practice to collect the seepage and convey seepage
away from the dam.
The Allen ash basin dam (GASTO-016) consists of an embankment oriented approximately
east-to-west, referred to as the north dike, and an embankment oriented approximately north-to-
south, along the Catawba River, referred to as the east dike. There are no engineered drainage
system features, or outfalls, associated with the Allen ash basin dam to be shown as required
by GS 130A-309.210(a)(2)(i).
2.4.2 Non-Engineered Seep Identification
Topographic maps of the site were reviewed to identify regions of the site where there was a
potential for ash-basin-related seepage to be present. These regions were determined by
comparing ash basin full pond elevations to adjacent topography with ground surface elevations
lower than the ash basin full pond elevation. HDR staff performed site observations within these
identified areas as part of NPDES inspections during the reapplication process during August
and September 2014 and documented locations where seepage was apparent at the time of the
site visit. These seeps are identified as required by GS 130A-309.210(a)(2)(ii) on Figure 2.
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SECTION 3 - DISCHARGE ASSESSMENT PLAN
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Section 3 - Discharge Assessment Plan
3.1 Purpose of Assessment
The purpose of the assessment is to determine whether existing, known discharges from toe
drain outfalls, seeps, and weeps associated with the coal combustion residuals surface
impoundment (ash basin) have reached the surface waters of the State and have caused a
violation of surface water quality standards as required by North Carolina General Statute 130A-
309.210(b).
Figure 2 and Table 1 present the background and downstream sampling locations to be
considered as part of this Discharge Assessment Plan (DAP). These locations may be
assessed by comparing surface water sampling analytical results of the associated background
location with the corresponding downstream location. For discharges located at the toe of a
dam, an upstream location within the channel may not have been possible to isolate for
comparison given the proximity to the ash basin, which would have the same chemical
composition as the discharge itself. As such, the upstream location was established upstream of
the ash basin and is considered “background.” For discharges located a distance from the ash
basin, an identified upstream or “background” location for sampling may be compared to the
downstream portion of the discharge channel. The background and downstream sampling
locations are shown on Figure 2 with “B” and “D” identifiers, respectively, and the corresponding
seep locations associated with the sampling locations are indicated on Table 1.
3.2 Assessment Procedure
The assessment procedure associated with the Allen ash basin is provided within this section.
In addition to the specific requirements for the assessment, Section 3.2 also provides the
general requirements, the frequency of assessment, documentation requirements, and a
description of the surface water quality analyses that will be performed.
3.2.1 General Assessment Requirements
Assessments are to be performed in three phases as follows:
• Observation and Sampling (assessment site visit)
• Evaluation
• Assessment Reporting
The assessment site visit shall be performed when the background and downstream locations
are accessible and not influenced by weather events. Locations on or adjacent to the ash basin
embankments should be performed within two months after mowing, if possible. In addition, the
assessment site visit should not be performed if the following precipitation amounts have
occurred in the respective time period preceding the planned assessment site visit:
• Precipitation of 0.1 inches or greater within 72 hours or
• Precipitation of 0.5 inches or greater within 96 hours
The assessments shall be performed under the direction of a qualified Professional Engineer or
Professional Geologist on a semi-annual basis during two nonadjacent quarters. The date of the
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initial assessment site visit shall be selected no later than 30 days from the approval of the
Discharge Assessment Plan and should fall within one of the semi-annual timeframes.
Additional seep locations that may have been identified and documented in an Identification of
New Discharge report(s) shall be reviewed prior to performing an assessment site visit, if
available.
3.2.2 Observation and Sampling
The initial assessment site visit should be performed to document baseline conditions of the
discharge channel including location, extent (i.e., dimensions of affected area), and flow of each
discharge. Discharge channel background and downstream locations should be verified using a
Global Positioning System (GPS) device. Photographs should be taken from vantage points that
can be replicated during subsequent semi-annual assessments.
Initial and subsequent assessment site visits shall document a minimum of the following to
respond to the requirements in 130A-309.210.1(b):
• Record the most recent ash basin water surface elevation and compare to the seep and
outfall and associated discharge location surface water elevations.
• For each discharge channel, the observer shall note the following as applicable on the
day of the assessment site visit:
o Is the discharge channel flowing at the time of the assessment site visit?
o Does the discharge channel visibly flow into a Water of the U.S. at the time of the
assessment site visit?
o How far away is the nearest Water of the U.S.?
o Document evidence that flow has or could reach a W ater of the U.S. (e.g.,
description of flow, including extent and/or direction) and describe the observed
condition. Evidence that flow could or has reached a Water of the U.S. may be
indicated by an inspection of the adjacent and downstream topographic drainage
features.
o Observe and document the condition of the discharge channel and outfall of the
engineered channel or seep location with photographs. Photographs are to be
taken from similar direction and scale as photographs taken during the initial
assessment site visit.
• Record flow rate within the discharge channel, if measureable, using the following
methods:
o Timed-volumetric method: Collect a volume of water from the discharge of the PVC
pipe directly into an appropriately sized container. Measure volumes (in mL) in the
field utilizing a graduated container. Record the amount of time (in seconds)
needed to collect the volume of water and calculate the flows (in MGD) for the
timed volume.
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o A V-notch weir apparatus will be installed, if necessary, during the initial
assessment site visit to impound seepage at locations with a defined channel.
Once the impounded seep reaches equilibrium discharge, flows will be measured
using the timed-volumetric method described above.
o Area-velocity method: Measure point velocities and water depth at a minimum of
20 stations along a transect setup perpendicular to the direction of flow using a
Swoffer® 3000 flow meter mounted to a standard United States Geologic Survey
(USGS) top-set wading rod. Utilize the average velocity and cross-sectional area of
the wetted channel to calculate flows in MGD.
• Collect water quality samples using the following methods:
o Collect background and downstream samples during a period with minimal
preceding rainfall to minimize potential effects of stormwater runoff. Collect
samples from the discharge channel at the flow measurement devices or directly
from the discharge into sample bottles while minimizing disturbance and
entrainment of soil/sediment. After collection, samples will be preserved and stored
according to parameter-specific methods and delivered to the laboratory under
proper Chain-of-Custody (COC) procedures.
o Analytical parameters for analysis include: Fluoride, Arsenic, Cadmium, Copper,
Chromium, Nickel, Lead, Selenium, and Mercury. This list includes all parameters
previously identified for seep sampling at Duke Energy power plants for which
relevant stream water quality standards are in place. (This list is responsive to the
statutory requirement for the discharge assessment to allow determination whether
discharges from toe drain outfalls, seeps, or weeps have reached surface waters
and caused a violation of surface water quality standards.) Analyses shall be
conducted by Duke Energy’s Huntersville Analytical Laboratory (NC Wastewater
Certification #248) and Pace Analytical Laboratories (NC Wastewater Certification
# 12). Laboratory analytical methods used for each constituent are provided in
Table 2.
o Seep In-situ measurements: In-situ field parameters (temperature and pH) shall be
measured utilizing calibrated field meters either at the discharge of the seep
directly, at the discharge of the flow measurement devices, or in the water pool
created behind the device if sufficient water depth did not exist at the device
discharge.
o Lake Wylie and Ash Basin Sample Collection Method: Water quality samples and
in-situ measurements from Lake Wylie shall be collected at a location upstream
(Lake Wylie-Upstream) and downstream (Lake Wylie-Downstream) of the ash
basin (Figure 1). Additionally, water samples and in-situ measurements shall be
collected from an in-process ash basin location such as near the Active Ash Basin
discharge tower (Figure 2). The grab samples shall be collected from the river and
basin’s surface (0.3 m) directly into appropriate sample bottles.
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3.2.3 Evaluation
Evaluation of the data from the initial assessment site visit will establish baseline conditions and
will serve as the basis for comparison for subsequent assessment site visit results. Evaluation of
observations and sampling results shall include location, extent (i.e., dimensions of affected
area), and flow of each discharge. The analytical results of the upstream and downstream
locations shall be compared to the 15A NCAC 2B standards for surface water quality upon
receipt to identify potential exceedances.
3.2.4 Assessment Reporting
Each assessment site visit shall be documented by the individual performing the assessment,
as described in Section 3.2.2 to meet the requirements in 130A-309.210.1(b). The report should
contain site background, observation and sampling methodology, and a summary of the
observations and descriptions of the discharge channels observed, changes in observations
compared to previous assessment events, estimates of flows quantities, and photographs of
discharges and outfalls of engineered channels designed or improved for collecting water from
the impoundment. Photographs are to be numbered and captioned. The flow and analytical
results shall be recorded and presented in tables similar to the examples provided as Tables 1
and 3. The analytical results shall be compared to the 15A NCAC 2B standards for surface
water quality and exceedances highlighted. This information shall be compiled, reviewed, and
submitted to NCDENR within 90 days from the Observation and Sampling event.
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Allen Steam Station Ash Basin
SECTION 4 - REFERENCES
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Section 4 - References
Duke Energy Carolinas, LLC. 2009. CERCLA 104(e) Request for Information to US
Environmental Protection Agency, Allen Steam Station, dated March 26, 2009.
Heath, R.C. 1984. “Ground-water regions of the United States.” U.S. Geological Survey Water-
Supply Paper 2242, 78 p.
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.
North Carolina Department of Environment and Natural Resources . 2007.Dam Operation,
Maintenance, and Inspection Manual, North Carolina Department of Environment and
Natural Resources, Division of Land Resources, Land Quality Division, 1985 (Revised
2007).
FIGURES
AND
TABLES
Table 1 – Allen Steam Station Ash Basin –Seep and Associated Discharge Locations and Descriptions Seep / Discharge ID Location Coordinates (NAD 83) Flow Description Flow Measurement (MGD) and Method Background Locations Discharge Location Discharge Location Coordinates (NAD 83) Latitude Longitude Latitude Longitude S-1 35°10.242’ -81°0.625’ Continuous 0.0004 timed-volumetric 1-B Tributary towards Lake Wylie 1-D 35°10.451’ -81°0.325’ S-2 35°10.426’ -81°0.344’ Continuous 0.0025 timed-volumetric S-3 35°10.513’ -81°0.360’ Continuous 0.0083 timed-volumetric S-4 35°10.513’ -81°0.360’ Continuous 0.0008 timed-volumetric S-5 35°10.621’ -81°0.366’ Continuous 0.0023 timed-volumetric Unconfined diffuse flow towards Lake Wylie 1-D S-6 35°10.626’ -81°0.369’ Continuous 0.0002 timed-volumetric S-7 35°10.664’ -81°0.380’ Continuous 0.0002 timed-volumetric S-8 35°10.706’ -81°0.391’ Continuous 0.0002 timed-volumetric Concentrated Flow in 12’ CMP 1-D S-9 35°11.146’ -81°0.394’ Continuous 0.0002 timed-volumetric Notes: 1. Flow description for each seep sample location is based on observation during site visits performed by HDR on August 21, 2014 2. Flow measurements and analytical samples were collected on September 4 and September 9, 2014 3. Location coordinates (degrees) for seep sampling locations are approximate and are in NAD 83 datum
Table 2 – Laboratory Analytical Methods
Parameter Method Reporting
Limit Units Laboratory
Fluoride (F) EPA 300.0 1 mg/l Duke Energy
Mercury (Hg) EPA 245.1 0.05 µg/l Duke Energy
Arsenic (As) EPA 200.8 1 µg/l Duke Energy
Cadmium (Cd) EPA 200.8 1 µg/l Duke Energy
Chromium (Cr) EPA 200.8 1 µg/l Duke Energy
Copper (Cu) EPA 200.8 1 µg/l Duke Energy
Lead (Pb) EPA 200.8 1 µg/l Duke Energy
Nickel (Ni) EPA 200.8 1 µg/l Duke Energy
Selenium (Se) EPA 200.8 1 µg/l Duke Energy
Table 3 – Allen Steam Station – Example of Surface Water/Seep Monitoring Flow and Analysis Results Table Parameter Units S-1 S-2 S-3 S-4 S-5 S-6 S-7 S-8 S-9 Lake Wylie-Upstream Lake Wylie-Downstream Fluoride mg/l 0.11 0.1 0.13 <0.1 <0.1 0.11 <0.1 0.17 <0.5 N/A N/A Hg - Mercury (71900) µg/l <1 <1 <1 <1 <1 <1 <1 <1 <1 <1 <1 As - Arsenic (01002) µg/l <1 <1 <1 <1 <1 <1 <1 <1 <1 <1 <1 Cd - Cadmium (01027) µg/l <1 <1 <1 <1 <1 <1 <1 <1 <1 <1 <1 Cr - Chromium (01034) µg/l 1.42 <1 <1 <1 <1 <1 <1 <1 <1 <1 <1 Cu - Copper (01042) µg/l <1 <1 <1 <1 <1 1.14 <1 <1 1.31 2.80 2.60 Pb - Lead (01051) µg/l <1 <1 <1 <1 <1 <1 <1 <1 <1 <1 <1 Ni - Nickel (01067) µg/l <1 1.58 <1 <1 8.23 2.29 <1 <1 2.78 N/A N/A Se ‐‐‐‐ Selenium (01147) µg/l <1 <1 <1 <1 <1 <1 <1 <1 <1 <1 <1 pH s.u. 6.63 6.33 6.95 6.92 5.56 4.67 5.64 8.11 7.52 N/A N/A Temperature °C 23.8 20.9 21.5 21.6 17.6 17.6 20.4 23.6 19 N/A N/A Flow MGD 0.0004 0.0025 0.0083 0.0008 0.0023 0.0002 0.0002 0.0002 0.0002 N/A N/A Notes: 1. Flow measurements and analytical samples were collected on September 4 and 9, 2014 2. N/A indicates not applicable 3. Lake Wylie samples were collected on August 27, 2014