NC0004774_Identification of New Discharges_20160503 (4)

Buck Combined Cycle Station Ash Basin
INSPECTION FOR IDENTIFICATION OF NEW DISCHARGES
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, through residual material in areas adjacent to the ash basin, or through the
bottom of the ash basin (if the flow eventually reaches the ground surface.) Therefore, a seep is defined
in this document as an expression of seepage at the ground surface above the ordinary high water mark
of any waters of the state. 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 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 basin).
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 the most recent ash basin water surface elevation.
2.6. Review previous Inspection for Identification of New Discharge Report(s) prior to performing
inspection.
2.7. Review the most recent previous dam inspections.
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,

Buck Combined Cycle Station Ash Basin
INSPECTION FOR IDENTIFICATION OF NEW DISCHARGES
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 following months: April to May and
October to November.
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.
In addition, the inspection should also include sampling. The facility shall sample for the following
constituents:
• Chlorides
•
Selenium `
• Fluorine
•
pH
• Mercury (method 1631E)
•
Total Dissolved Solids
• Barium
•
Antimony �(
• Iron
•
Thallium X
• Manganese
•
Molybdenum
• Zinc
•
Boron k
• Arsenic
•
Aluminum is
• Cadmium
•
Sulfate
• Chromium
•
Total Suspended Solids
• Copper
•
Temperature
• Lead
•
Specific Conductance
• Nickel
This sampling is necessary to demonstrate if a discharge/seep contains Coal Combustion Products
(CCPs), if it is some other type of waste stream, or if the seepage is simply not associated with a process
wastewater discharge.
F)

Buck Combined Cycle Station Ash Basin
INSPECTION FOR IDENTIFICATION OF NEW DISCHARGES
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 Channels
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)
7.2. Document the condition of the outfall of the engineered channel with photographs.
Photographs are to be taken from similar direction and scale as 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.
7.6. Sample for the following constituents to demonstrate if a discharge/seep contains CCPs, if it is
some other type of waste stream, or if the seepage is simply not associated with a process
wastewater discharge:
• Chlorides
•
Selenium
• Fluorine
•
pH
• Mercury (method 1631E)
•
Total Dissolved Solids
• Barium
•
Antimony
• Iron
•
Thallium
• Manganese
•
Molybdenum
• Zinc
•
Boron
• Arsenic
•
Aluminum
• Cadmium
•
Sulfate
• Chromium
•
Total Suspended Solids
• Copper
•
Temperature
• Lead
•
Specific Conductance
• Nickel
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Buck Combined Cycle Station Ash Basin
INSPECTION FOR IDENTIFICATION OF NEW DISCHARGES
8. Inspection For New Seeps Not Captured by Engineered Channels
inspect areas below the ash basin full pond elevation and within the slope -aquifer system 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. Investigations should
include areas where perimeter ditches/swales are located around active or inactive ash basins.
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
photograph documenting original photograph of seep. Describe the approximate
dimensions and flow conditions of the seep. This information may help todemonstrate,
changing site conditions over time.
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b) If flow measurement device is installed at the outfall, record flow.
c) Observe seep to determine if changes to location, extent, or flows are present. Document
changes to location, extent, and/or flow amount or pattern. lvl
4
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d) Sample for the following constituents to demonstrate if a discharge/seep contains CCPs, if it
is some other type of,waste stream, or if the seepage is simply not associated with a process
wastewater discharge:
• Chlorides
•
Selenium
• Fluorine
•
pH
• Mercury (method 1631E)
•
Total Dissolved Solids
• Barium
•
Antimony
• Iron
•
Thallium
• Manganese
•
Molybdenum
• Zinc
•
Boron
• Arsenic
•
Aluminum
• Cadmium
•
Sulfate
• Chromium
•
Total Suspended Solids
• Copper
•
Temperature
• Lead
•
Specific Conductance
• Nickel
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.
i
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Buck Combined Cycle Station Ash Basin
_ INSPECTION FOR IDENTIFICATION OF NEW DISCHARGES
c) Describe the approximate dimensions and flow conditions of the seep.
d) Sample for the following constituents to demonstrate if a discharge/seep contains CCPs, if it
is some other type of waste stream, or if the seepage is simply not associated with a process
wastewater discharge:
• Chlorides • Selenium -
• Fluorine • pH
• Mercury (method 1631E) • Total Dissolved Solids .
• Barium • Antimony
• Thallium'
• Iron
isJ • Manganese • Molybdenum
• Zinc • Boron
• Arsenic • Aluminum
Y 1
• Cadmium • Sulfate
• Chromium • Total Suspended Solids
• Copper__ • Temperature
• Lead • Specific Conductance
• Nickel
e) Map the location of new seep or indicator of seep using GPS coordinate points collected
` {l
during the site visit.
f) If seep or indicator of seep was not"caused by changes in surface water drainage and if the
location is below the ash basin pondtievation, 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. All seeps located below the ash basin full pond elevation and within the slope -aquifer
system shown are to be shown on Figure A-2.
10. Decision Flow Chart
The decision flow chart developed to determine whether a new seep discharges from the ash basin is
found on Figure A-1.
11. Procedure for Notifying NCDENR DWR if New Discharge Is Confirmed
Duke Energy will notify the DWR Regional Office by mail within 5 days after the discovery of a new seep
unless a different timeframe is established and specified in reissued permits. If the new seep represents
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Buck Combined Cycle Station Ash Basin
INSPECTION FOR IDENTIFICATION OF NEW DISCHARGES
a significant change in flow or pollutant loading from the facility, or a bypass or upset, it may fall under
provisions that would require immediate reporting.
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J

Buck Combined Cycle Station Ash Basin
INSPECTION FOR IDENTIFICATION OF NEW DISCHARGES
Notes:
Figure A-1 - Decision Flow Chart for Determining If New Seep Represents Discharge From the Ash
I Review previous seep inspection reports I
I Perform inspection for new seeps I
Is new seep located below
elevation of ash basin?
Yes
Is new seep located within slope -aquifer
boundary system as shown on Figure A-2?
Yes
Does new seep present concentrated flow that
could be collected. measured and sampled?
Yes
Collect water quality sample at seep and perform the following analyses:
• Field parameters: pH, specific conductance, temperature, turbidity.
• Constituent analyses: NPDES parameters, plus major cations and anions
Compare 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 basin
Do analytical results from new seep
indicate discharge from ash basin?
Yes 1
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.
No
No
New seep is not hydraulically
related to ash basin
New seep presents diffuse flow conditions.
No Photograph, map location; add to seep
location map, describe flow conditions, and
approximate area of seepage.
No
New seep is not related to 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.
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 NCDENR DWR.
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NOTES:
1. PARCEL DATA FOR THE SITE WAS OBTAINED FROM DUKE ENERGY REAL ESTATE AND IS APPROXIMATE
2. WASTE BOUNDARY AND ASH STORAGE AREA BOUNDARY AREAPPROXIMATE
3. AS. BUILT MONITORING WELL LOCATIONS PROVIDED BY DUKE ENERGY AND WSP.
4. COMPLIANCE SHALLOW MONITORING WELLS (S) ARE SCREENED ACROSS THE SURFICIAL WATERTABLE
S. COMPLIANCE DEEP MONITORING WELLS (D) ARE SCREENED IN THE TRANSITION ZONE BETWEEN COMPETENT BEDROCK ANDTHE REGOUTH.
6. TOPOGRAPHY DATA FOR THE SITE WAS OBTAINED FROM WSP DATED NOVEMBER 2013.
7. AERIAL PHOTOGRAPHY WAS OBTAINED FROM WSP DATEDAPRIL 17,2014.
8. THE COMPLIANCE BOUNDARY IS ESTABLISHED ACCORDING TO THE DEFINITION FOUND IN 1SA NCAC 02L A107 (a}
TOPOGRAPHIC CONTOURS LOCATED WITHIN THE WASTE BOUNDARYAND OTHERS SPECIFIC AREAS SUCH AS DAMS, DIKES, ETGARE2-FTCONTOUR INTERVALS
SCALE (FEET)
200' 0 200' d00'
/- = 600'
LEGEND:
DUKE ENERGY PROPERTY BOUNDARY
ASH BASIN WASTE BOUNDARY
ASH STORAGE AREA BOUNDARY
COMPLIANCE BOUNDARY
_ COMPLIANCE BOUNDARY COINCIDENTWITH DUKE
PROPERTY BOUNDARY
STREAM
TOPOGRAPHIC CONTOUR (4-FT INTERVAL)'
AREA TO BE INSPECTED FOR SEEPS
ASH BASIN COMPLIANCE GROUNDWATER MONITORING
d WELL
AREAS TO BE INSPECTED FOR SEEPS
DUKE ENERGY CAROLINAS, LLC
BUCK COMBINED CYCLE STATION ASH BASIN
NPDES PERMIT NO. NC0004774
ROWAN COUNTY, NORTH CAROLINA
DATE
2/18/2015
FIGURE
A-2