ILF Bottom Ash Road_PLM Report (4)

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I I I Enw
May 24, 2022
Duke Energy Marshall Steam Station
EHS Groundwater & Waste Programs
8320 NC Highway 150
Terrell, North Carolina 28682
Attention: Ms. Ashley Healy, P.G.
Reference: Clean Closure Verification - Visual Confirmation and PLM Results
Duke Energy Marshall Steam Station
Confirmatory Soil Sampling — Marshall Steam Station Bottom Ash Roads, Industrial Landfill No
(Permit No. INDUS-1812)
S&ME Project No. 212013, Ph. 06
Ms. Healy:
S&ME, Inc. (S&ME) is submitting the enclosed summary of results supporting the removal of Coal Combustion
Residual (CCR) material by visual verification and Polarized Light Microscopy (PLM) analysis results within the
bottom ash roads in the Industrial Landfill No. 1 (Permit No. INDUS-1812) (ILF) at Duke Energy's Marshall Steam
Station, located in Catawba County, North Carolina.
This summary letter is provided so that the North Carolina Department of Environmental Quality Solid Waste
Section (NCDEQ — SWS) may review PLM analytical results prior to our formal report documenting our full clean
closure verification field activities as outlined in the June 17, 2020 Excavation Soil Sampling Plan for Bottom Ash
Road Excavation dated June 17, 2020, approved by NCDEQ-SWS on July 8, 2020 (FID 1418126).
We have attached Table 1 — PLM Sample Results and Soil Sampling Summary to this letter which includes soil
sample descriptions, including visual verification that CCR material has been removed, and supporting PLM
analysis results for samples collected by S&ME personnel during sampling events conducted May 18, 2022. A
corresponding map, Figure 1 — ILF Bottom Ash Road Clean Closure Sampling Location Summary is enclosed
as well, depicting sample locations at the ILF bottom ash road that have been sampled and analyzed using the
PLM method for CCR material.
Please note that samples collected in the bottom ash road May 18, 2022 contained no detectable CCR material.
The clean closure benchmark value for CCR material in soil samples is 50%.
S&ME thanks you for your receipt of these records. Should you have any questions or need additional
information, please do not hesitate to contact us at [phone].
S&ME, Inc. 12016 Ayrsley Town Blvd., Suite 2-A I Charlotte, NC 282731 p 704.523.4726 1 www.smeinc.com

EHS Groundwater & Waste Programs
Respectfully Submitted,
5&ME. Inc.
May 24, 2022
Page 2
Skyler Schmal, GIT Erin Kinsey, P.E.
Staff Professional Geologist II Project Engineer
Senior Reviewed By: Julie P. Robertson, P.G. (Registration No. 1995)
Enclosures: Table 1 — PLM Results and Soil Sampling Summary
Figure 1 — ILF Bottom Ash Road Clean Closure Sampling Location Summary
cc: James Malloy, Project Manager, Duke Energy Marshall Steam Station
S&ME, Inc.

Table 1: PLM Sample Results and Soil Sampling Summary
Bottom Ash Road - Industrial Landfill No. 1 (Permit No. INDUS-1812)
Duke Energy Marshall Steam Station
SWE Project Number: 212013, Ph. 06
Notes•
(1) For the purposes of PLM method, Fly Ash is defined as any particle consistent with Coal Combustion Residual (CCR) material.
(2) ND = Not Detected. The PLM Method Reporting Level is 1%; samples with less than 1% CCR are considered ND.
'Actual sample depths may vary due to sampling method and volume of soil needed for laboratory testing.
2CCR = Coal Combustion Residuals
3Residual Material (RES): Residuum and saprolitic material that is a product of weathered bedrock.
4United Soil Classification System descriptions are provided for each sample description and are denoted with a two letter abbreviation following the soil type.
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