HomeMy WebLinkAboutNC0003417_Submittal of Revised Sampling and Analysis Plan_20161118Richard E. Baker, Jr.
Director
EHS-CCP Environmental Programs
526 S. Church Street
Mail Code: EC13K
Charlotte, NC 28202
Mr. David May
North Carolina Department of Environmental Quality
Washington Regional Office
943 Washington Square Mall
Washington, NC 27889
Subject: Duke Energy Progress, LLC
HF Lee Energy Complex NPDES Permit NC0003417
Revised Sampling and Analysis Plan – Hurricane Matthew Response
Wayne County
Dear Mr. May:
On November 9, 2016, Duke Energy received the Plan of Action Review from The Department
of Environmental Quality (DEQ) Division of Water Resources (DWR). The review letter was in
response to Duke Energy’s Plan of Action submitted to DWR on October 27, 2016. Duke
Energy has attached an update to the Sampling and Analysis Plan that incorporates changes
resulting from DEQ’s review as well as Duke Energy’s review of current sampling results.
Duke Energy has performed sampling of the Neuse River in the area around the HF Lee Plant
for six weeks following Hurricane Matthew. To date, Duke Energy has not seen any appreciable
differences in the water quality above the inactive basins and downstream of the inactive
basins. Duke Energy proposes to continue the current sampling plan until December 1, 2016,
and requests that the Division allow for the cessation of surface sampling on December 1, 2016.
After that date, Duke Energy will summarize and evaluate the findings of all sampling events in
a report and submit it to DWR Washington Regional Office on January 31, 2017.
If there are any questions regarding this response, Mr. Steve Cahoon via phone at (919) 546-
7457 or via email at steve.cahoon@duke-energy.com.
Sincerely,
Richard E. Baker, Jr.
Director – Environmental Programs - CCP
Attachments
1
H. F. LEE POST-FLOOD
SAMPLING AND ANALYSIS PLAN
1.0 INTRODUCTION
On October 8, 2016, rains from Hurricane Matthew brought extreme flooding to most of eastern North
Carolina. The flood waters from Matthew eclipsed Neuse River flood stage levels from Hurricane
Floyd in 1999. Duke Energy’s decommissioned H. F. Lee Plant (Lee Plant), including the inactive ash
basins, was inundated and submerged under the flowing flood waters. From the basins, an estimated 2
to 2.5 cubic yards of coal combustion residual (CCR) material (primarily buoyant, inert cenospheres)
was released to the flood waters overlying the Neuse River.
Duke Energy began conducting daily surface water sampling for the extensive priority pollutants as
soon as it was safe to access at the plant site. The data generated to date were transmitted with Duke’s
October 27, 2016 letter to DEQ. Based on Duke Energy’s evaluation of the data it is proposed that
surface water sampling be continued for the next several weeks at a reduced frequency and for a
reduced list of parameters. To date, only three data points have been measured above the NC 2B
limits.
In addition to the surface water sampling described above, this monitoring plan proposes the initiation
of two rounds of sediment/water sampling intended to confirm that there were no short-term
environmental impacts to the Neuse River from the release of CCR materials associated with the
flooding event.
2.0 PURPOSE
The purpose of this sampling plan is to confirm that no environmental impacts resulted from the
release of CCR material to the Neuse River during flooding conditions associated with Hurricane
Matthew. This plan has been developed in response to a request by the North Carolina Department of
Environmental Quality (NCDEQ) to develop a Plan of Action. Water samples will be collected until
the week ending December 2, 2016, to continue to assess surface water quality, and sediment samples
will be collected to look for evidence of CCR related constituents in depositional areas of the Neuse
River.
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3.0 OBJECTIVES
The objectives of this sampling plan are to continue surface water sampling to confirm the absence of
water quality impacts and provide an assessment of the presence and relative concentration of CCR
materials in sediment in the vicinity and downstream of the Lee Plant that were mobilized by flood
waters from Hurricane Matthew.
4.0 NATURE OF STUDY
The assessment will include surface water sampling, sediment sampling and analysis of ash related
constituents in water and sediments of the Neuse River.
Surface water sampling will continue at four designated locations (see attached) for a reduced number
of parameters through December 1. Samples will be collected on Mondays and Thursdays at the
following locations:
1) Neuse River – Upstream Inactive Ash Basins – located at the Ferry Bridge Rd crossing
over the Neuse.
2) Inactive ash basin area – near area of suspected cenosphere release
3) Neuse River near the area of the cooling pond dam breach
4) Downstream cooling pond – collected within the Neuse, south of the site where Stevens
Mill road crosses the river
Duke Energy will analyze the surface water samples for field parameters (temperature, dissolved
oxygen, pH, conductivity, turbidity) and the following metals (dissolved and total phases):
Aluminum Total Hardness
Antimony Iron
Arsenic Lead
Barium Nickel
Beryllium Selenium
Boron Silver
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Cadmium Thallium
Chromium Zinc
Copper Mercury (low level)
Laboratory analysis for these parameters will use a Practical Quantitation Limit (PQL) that is
indicative of laboratory capability and the analytical methodology. Raw lab data will be provided for
the analyses identifying all detections and referencing PQL and detection limits for performed
analyses.
Based on the non-detects for all of the Priority Pollutants collected since Hurricane Matthew, no
additional analyses for these parameters is warranted. In accordance with the Department’s November
9, 2016 letter, priority pollutant sample collection and analysis has been discontinued.
Sediment sampling will be conducted twice at one upstream (background) site and three downstream
sites (Stations DN1, DN2, and DN3) at possible depositional areas downstream of known release
points and the results will be analyzed using appropriate approved methods. Water samples will be
collected concurrently at the water/sediment interface at these sampling locations. Sampling locations
were selected in the field on November 17, 2016 based on river conditions and observations of likely
depositional areas. Coordinates for the sampling locations have been updated in Table 1. Data from
these locations will be compared to sampling results from the background station (UP1) well above the
plant and known release points. Both water and sediments data will be compared to the appropriate
screening values (from combination of multiple agency sources) used in the Dan River ash release
assessment. Also, where historical data exists, comparisons will be made to pre-release conditions.
5.0 LOCATION AND DURATION OF SEDIMENT SAMPLING
The assessment will be conducted at three downstream areas and one upstream area in the Neuse River
(Figure 1). For the purposes of this assessment, the sampling areas will be referred to as stations. The
survey area within the Neuse River covers approximately 12 kilometers of the river from the upstream
Station (UP1) to the downstream- most Station (DN3; See map). Station UP1 is located at the Ferry
Bridge Road wildlife access boat ramp and is Duke Energy’s historic background sampling location
for the Lee Plant. Data at this station will serve as the upstream reference to which data from the other
stations will be compared. Station DN1 is a downstream station located near the inactive ash basins
where cenospheres were observed to be migrating from along with the flood waters. Station DN2 is
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located downstream near the cooling pond breach and Station DN3 is located at the Stevens Mill
Bridge (the most downstream sampling location). The downstream locations were selected to be
representative of potential depositional areas (i.e., the inside bank of bends where the greatest ash
deposition potentially occurred). Also, limited historical water chemistry data, including trace
elements, from within the monitoring reach will serve as another dataset to compare data from this
monitoring effort to that collected prior to the flooding event. Duke Energy plans to perform this
sediment sampling in the Neuse River twice. Should the results of the sampling indicate ash presence
in the sediment or a significant difference in ash-related conditions (percent ash, arsenic or selenium
values) from upstream to downstream the sampling will be repeated and results evaluated for further
action.
6.0 SEDIMENT SAMPLING AND ANALYSIS PLAN
6.1 Limnology
The Duke Energy sediment sampling and analysis plan including program, sampling location
descriptions, and sampling frequency is described in Tables 1-3. Duke will monitor for the ash
indicator analytes arsenic and selenium in both total and dissolved fractions, as well as the other
metals listed above for the surface water sampling. The water chemistry samples will be collected
from the water column near the sediment-water interface via a submersible sampler (peristaltic pump
and hose), transferred to pre-prepared non-metal bottles, field filtered (for dissolved metals), quickly
sealed, and returned to the laboratory on ice for analyses. Analyses will be run by a laboratory (Pace
Analytical) certified in North Carolina using approved EPA methods (Table 3). The analytical quality
assurance and control measures performed by the external contract laboratory will be consistent with
their certifications/accreditations and approved SOPs. In addition, one duplicate per sample set (10%
duplicate/blank ratio) will be included.
Laboratory analysis for these parameters will use a Practical Quantitation Limit (PQL) that is
indicative of laboratory capability and the analytical methodology. Raw lab data will be provided for
the analyses identifying all detections and referencing PQL and detection limits for performed
analyses.
The limnological (field) parameter list is appended in Appendix 2. Water quality analysis will be
conducted and generally includes temperature, dissolved oxygen, pH, conductivity, and turbidity,
which will be measured in the field using a multi-parameter meter with a submersible sonde according
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to Duke Energy procedure NR00097 (approved by NCDEQ under the Duke Energy Progress
Biological Laboratory Certification #006).
6.2 Percent Ash and Trace Element Monitoring in Sediments
The primary potential environmental impacts would be from CCRs settling to the river bottom where
accumulation of trace elements in the various compartments of the aquatic ecosystem could occur.
Therefore, percent ash will be determined at the four sampling locations in this monitoring plan. Duke
Energy does not anticipate significant quantities of ash to be present in the river sediments based on
ours as well as NCDEQ’s experience with the Dan River ash release. If very low ash percentages (0-
1%) are found, this sampling will be discontinued. Along with percent ash, arsenic and selenium
concentrations in sediments will be evaluated using EPA Method 6020. The results will be compared
against the sediment analyte/screening values list in Appendix 2. Sediment samples will also be
analyzed for the metals listed in Section 4.0. Note that the low level mercury method is not applicable
to sediments so mercury will be analyzed using the standard mercury method.
The sediment sampling locations will be selected based on Duke Energy’s extensive experience with
the Dan River monitoring program. We found that ash settles primarily in depositional areas along the
inside banks of river bends. If there is accumulation these areas are the most likely places where
significant accumulation would occur. Exact sample locations were selected in the field on November
17, 2016. Samples will be collected by plastic core tubes in which approximately 12 inches of bottom
sediments are taken, photographed, and the first six inches collected for percent ash and trace element
analysis. The samples will be returned and sent to the appropriate external laboratory for analysis.
7.0 DATA MANAGEMENT
All data generated under this sampling plan will be recorded electronically and uploaded to the Duke
Energy long-term database. All data will undergo internal QA/QC protocols to ensure accuracy of the
stored data. When used, GPS data will be presented as decimal degree coordinates. Geographical
Information System (GIS) will be utilized when appropriate along with compatible programs for two-
dimensional graphic display for presentation or reporting purposes.
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8.0 REPORTING
A written report from the sampling plan and results will be provided to NCDEQ before the end of
2016 after all analyses have been completed and the results are available. Based on the results, a
decision will be made regarding continuation or termination of sampling.
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Figure 1. H. F. Lee environmental monitoring program sampling locations designations.
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Table 1. H. F. Lee sediment monitoring program sample location designations and
descriptions.
Sampling
Station
Sampling
Program
Description Decimal Degree Coordinates
Upstream (Downstream)
UP Limnology and
Sediments
Neuse River
upstream of H. F.
Lee Plant and all
release points
Lat. 35.35560°
Long. -078.14027°
DN1 Limnology and
Sediments
Neuse River near the
inactive ash basin
release point
Lat. 35.37852°
Long. -078.10150°
DN2 Limnology and
Sediments
Neuse River near the
cooling pond breach
Lat. 35.37600°
Long. -078.05774°
DN3 Limnology and
Sediments
Neuse River at the
Stevens Mill Bridge
Lat. 35.35890°
Long. -078.07748°
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Table 2. H. F. Lee surface water and sediment monitoring program.
Program Frequency Location
Surface water quality
(aluminum, antimony,
arsenic, barium, beryllium,
boron, cadmium,
chromium, copper, iron,
lead, nickel, selenium,
silver, thallium, zinc,
mercury)
Water quality
(Field parameters:
temperature, pH,
dissolved oxygen,
specific conductance,
turbidity)
Two per week through December 1, 2016
Twice
-Neuse River – Upstream Inactive
Ash Basins – located at the Ferry
Bridge Rd crossing over the
Neuse.
-Inactive ash basin area – near
area of suspected cenosphere
release
-Neuse River near the area of the
cooling pond dam breach
-Downstream cooling pond –
collected within the Neuse, south
of the site where Stevens Mill
road crosses the river
Stations UP, DN1, DN2, and
DN3 (surface only)
Water chemistry
(sediment-water
interface)
Twice
Stations UP, DN1, DN2, and
DN3 (sediment-water interface)
Percent Ash
(sediment)
Twice (to determine ash presence and the
need to continue sampling; if needed
weekly sampling will continue until all
samples are non-detect for percent ash)
Stations UP, DN1, DN2, and
DN3
Trace elements
(sediment)
Twice (As and Se will be co-sampled as
along with percent ash samples as long as
they are collected)
Stations UP, DN1, DN2, and
DN3
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Table 3. Field sampling and laboratory methods for the H. F. Lee sediment sampling program.
Program Method
Water quality Temperature, dissolved oxygen, pH, specific conductance, and turbidity will be
measured with a calibrated multiparameter instrument. Measurements will be taken
from surface from the surface only at river stations.
Water chemistry Samples will be taken with a nonmetallic sampler, transported to the laboratory on ice,
and then analyzed according to EPA methods and or Standard Methods (SM).
Parameters include dissolved and total aluminum, arsenic, and selenium (EPA 200.8).
Percent ash Field sampling followed by polarized light microscopy (Method OPT.023.2).
Trace elements All media, except water, will processed according to EPA Method 3050B EPA and
analyzed by EPA Method 6020. Quality control will be achieved by analytical
standards, replicate and spiked samples, and certified reference materials.
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Appendix 1
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Appendix 2
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Water Chemistry
Screening Values
ANALYTE (MDL) SCREENING VALUES-Aquatic
Life/Human Health Analytical Methodology
Arsenic (As) (µg/L) 50/10 EPA 200.8, Rev. 5.4 1994
(Aqueous)
Selenium (Se) (µg/L) 5/NA EPA 200.8, Rev. 5.4 1994
(Aqueous)
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Sediment Screening Values
ANALYTE
(MDL wet µg/g)
SEDIMENT
SCREENING VALUES
(μg/g wet weight)
Arsenic (0.013) 9.8
Selenium (0.075) 2