Visual Confirmation 1982 Ash Basin FINAL 2-28-18

t.,
Water Resources w
Environmental Quality
February 28, 2018
Ed Sullivan
Duke Energy
526 South Church Street
Mail Code EC13K
Charlotte, North Carolina 28202
ROY COOPER
Governor
MICHAEL S. REGAN
Secretary
LINDA CULPEPPER
Interim Director
Subject: Visual Confirmation of Coal Ash Removal from the 1982 Ash Basin at the
Asheville Steam Electric Plant - Documentation of Closure
Dear Mr. Sullivan,
The North Carolina Department of Environmental Quality's Division of Water Resources
(Division) has received information provided for the Documentation for Closure — Visual
Removal of Ash for the 1982 Ash Basin at the Asheville Steam Electric Plant (Asheville Plant)
that includes:
• The September 22, 2016 CCR Removal Verification Letter 1982 Ash Basin from AMEC
Foster Wheeler that documents removal of coal ash utilizing visual confirmation of
samples collected on a 100-foot by 100-foot grid, and
• The September 29, 2016 Asheville Plant 1982 Ash Basin Closure Polarized Light
Microscopy (PLM) Results Summary Technical Memorandum from SynTerra
Corporation that documents confirmatory laboratory test by polarized light microscopy
on samples collected on an one -acre grid.
These reports document the results of soil samples collected during excavation of coal ash
residuals (CCR) in the 1982 Basin to support closure activities with respect to protection of
groundwater.
The objective of the Division's review of the information provided is to confirm whether sample
collection and analysis conducted during excavation are consistent with recommended technical
direction outlined in the Division's CCR Surface Impoundment Closure Guidelines for Protection
of Groundwater dated November 4, 2016. The review includes verification of visual confirmation
of coal ash for excavation endpoints and that an adequate dataset has been collected to evaluate
whether soil contamination left in place can meet performance standards necessary for protection
of groundwater within the footprint of the closed impoundment.
�/ Nothing Compares,,..
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

The results of the Division's review are summarized below:
Asheville Steam Electric Plant Soil Excavation Plan Implementation— Division Review
CCR Surface Impoundment
Meets
Closure Guidelines for
Duke Energy Final Results
gynaesus
Division
Protection of Groundwater
Guidelines
recommendations
es/No
Visual Confirmation Via PLM:
Visual confirmation done on an acre -
Samples on 100 ft rid at depth.
ids stem.
No
Visual Confirmation Via PLM:
Depths ranged from 0.5 feet to 3 feet.
Minimum depth of 2 feet bgs
Samples were collected at auger
Yes
refusal.
Visual Confirmation Via PLM:
All samples at or below 50%
Yes
Complete when less than 50% ash
Remaining Soil Sampling: Done
All samples at or below 50% were
on soils with less than 50% ash.
used for analysis
Yes
All samples were analyzed regardless
Remaining Soil Sampling: Taken
of depth. All locations with soil
from first 6 inches of soil.
present had a 0.5-foot sample
yes
collected.
Remaining Soil Sampling:
Performed on acre -ids stem.
Samples taken on acre -grid system.
Yes
Soil Analysis: Sample for
Sample analyzed for Antimony,
Antimony, Aluminum, Arsenic,
Aluminum, Arsenic, Barium,
Barium, Beryllium, Boron,
Beryllium, Boron, Cadmium,
Cadmium, Calcium, Chloride,
Calcium, Chloride, Chromium (total
Chromium (total and hexavalent),
and hexavalent), Cobalt, Copper, Iron,
Cobalt, Copper, Iron, Lead,
Lead, Magnesium, Manganese,
Yes
Magnesium, Manganese,
Mercury, Molybdenum, Nickel,
Mercury, Molybdenum, Nickel,
Nitrate as Nitrogen, pH,
Nitrate as Nitrogen, pH, Potassium,
Potassium, Selenium, Silver,
Selenium, Silver, Sodium, Strontium,
Sodium, Strontium, Sulfate,
Sulfate, Thallium, Vanadium, and
Thallium, Vanadium, and Zinc.
Zinc.
Soil Analysis: For sites with final
Samples analyzed for SPLP and total
infiltration — Analyze for SPLP
concentrations
Yes
and total concentrations
Based on the Division's review, Duke Energy met the overall intent of the CCR Surface
Impoundment Closure Guidelines for Protection of Groundwater technical direction with respect
to visual confirmation of coal ash and sample collection needed to address criteria for the
protection of groundwater associated with the Asheville 1982 Ash Basin. Visual field
confirmation of coal ash by PLM was conducted by Duke Energy on an one -acre grid as opposed
to the recommended 100-foot grid spacing, but data collected provides adequate coverage to

confirm the Division's excavation expectations. As required by the groundwater guidelines,
flow and transport modeling simulations that demonstrate whether or not any potential CCR
residuals in soil contribute to 2L standards violations in groundwater must be provided to the
Division; these model results must be presented in the upcoming Corrective Action Plan for the
facility.
For reference to future excavation activities at coal ash facilities, Duke Energy should conduct
visual confirmation of coal ash by on a 100-foot grid as stated in the CCR Surface Impoundment
Closure Guidelines for Protection of Groundwater.
If you have any questions, please feel free to contact Ted Campbell (Asheville Regional Office) at
[phone], or Steven Lanter at [phone].
Sincerely,
S. Ja Zii merman, P.G.,
Environmental Program Manager
cc: ARO Regional Office Supervisor
WQROS Central File Copy