FRO WARO WIRO Technical Direction and Action Items 10-19-17

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Water Resources
Environmental Quality
October 18, 2017
Ed Sullivan
Duke Energy
526 South Church Street
Mail Code EC 13K
Charlotte, North Carolina 28202
ROY COOPER
Governor
MICHAEL S. REGAN
Secretary
S. JAY ZIMMERMAN
Director
Subject: Technical Direction and Action Items,Fayetteville,Washington, and Wilmington Regional
Offices Meeting - June 28, 2017
Dear Mr. Sullivan:
On September 29, 2017, the North Carolina Department of Environmental Quality's Division of Water
Resources (Division) received the revised meeting minutes from the June 28, 2017, Fayetteville,
Washington, and Wilmington Regional Offices combined meeting at the Wilmington Regional Office. As
part of the process agreed upon to facilitate completion of the site assessments and corrective action plans,
the Division provides the following summary of technical direction and action items discussed during the
meeting:
• Technical Direction and Action Items
o Program -wide Issues with respect to the Coastal Plain Sites
• Duke Energy indicated a need for clarification regarding the compliance boundary
for the Comprehensive Site Assessments.
■ In general, the lack of suitable background soil samples is a significant issue for
the three sites discussed. This data gap must be addressed.
• Plans for collection of additional background soil data were requested.
• The Division will provide a letter regarding a review of background data sets and
the deficiencies for each coal ash facility.
o L.V. Sutton Energy Complex
• A pH of <9.7 will be the threshold for inclusion of samples in the background
dataset for the Pee Dee aquifer.
• Vertical delineation of contamination using the isotope analysis remains the only
critical groundwater data gap.
• Additional background soil samples will need to be collected to generate a valid
dataset for analysis.
• Duke Energy will provide an update for the ash bottom investigation in the 1971
pond.
• Duke Energy will provide an update for the investigation of the Former Ash
Disposal Area.
• The results of the ash bottom investigation shall be used in the calibration of the
updated fate and transport models.
• Additional surface water sampling will be required; further direction regarding
sampling objectives will be provided by the Division.
State of North Carolina I Environmental Quality I Division of Water Resources
Water Quality Regional Operations Section
1636 Mail Service Center I Raleigh, North Carolina 27699-1636
919-707-9129

o W. H. Weatherspoon Power Plant
Information regarding the schedule for ash excavation was requested.
Additional background soil samples are needed to develop an adequate data set
for analysis. Duke Energy will provide soil background locations.
■ Additional groundwater data for the lower Yorktown and Pee Dee were
requested to provide a more robust dataset for preliminary background threshold
value (PBTV) determinations.
• Utilization of the AW-3 cluster to provide suitable background data was
suggested. Multiple lines of evidence were requested to confirm a hydraulic
divide between the AW-3 well cluster and the ash basin exists.
• In addition, confirmation of no impacts from coal ash in the AW-3 well cluster is
needed to support using related data for PBTV determinations. Water quality
analysis described in the EPRI 2012 Coal Ash Signature Evaluation document
was suggested to assess whether groundwater in AW-3 wells are impacted by the
ash basin.
• Information regarding redevelopment of existing background wells and possible
installation of new background wells was requested.
o H. F. Lee Energy Complex
• Duke Energy reported that 10 additional wells were being installed on the newly
acquired properties to determine if a groundwater recovery system would be
necessary. Duke Energy will provide an update on the well installation and any
related sample results.
• Additional surface water sampling will be required; further direction regarding
sampling objectives will be provided by the Division.
• For the inactive basin, Duke Energy indicated that arsenic concentrations continue
to be elevated in groundwater samples collected from the new shallow monitoring
well to the southwest, however, leading edge constituents such as boron are not
seen at elevated concentrations in the area. Stiff and or Piper diagrams may be
helpful to assess if the arsenic exceedance is from coal ash or naturally occurring
concentrations. Water quality analysis described in the EPRI 2012 Coal Ash
Signature Evaluation document should be considered to evaluate potential coal ash
impacts in groundwater at the facility.
If you have any questions, please feel free to contact Geoff Kegley (Wilmington Regional Office) at (910)
796-7215, Kent White (Fayetteville Regional Office) at [phone], Will Hart (Washington Regional
Office) at [phone], or Steve Lanter (Central Office) at [phone].
Sincerely,
2isga d, Section Chief
Water Quality Regional Operations Section
Division of Water Resources
cc: FRO, WARD, and WIRO WQROS Regional Office Supervisors
WQROS Central Office Copy