Data Gap Evaluation REV 2 Comments_20191004

ROY COOPER
Governor
NCHAEL S. REGAN
Secretory
LINDA CULPEPPER
Director
Paul Draovitch
Senior Vice President
Environmental, Health & Safety
Duke Energy
526 South Church Street
Mail Code EC3XP
Charlotte, North Carolina 28202
NORTH CAROLINA
Envi vnmentaJQuaUty
October 4, 2019
Subject: Data Gap Evaluation Work Plan (REV 2) Comments — Marshall Steam Station
Dear Mr. Draovitch:
On September 17, 2019, the North Carolina Department of Environmental Quality Division of
Water Resources (Division) received the proposed Data Gap Evaluation Work Plan (REV 2) for
the Marshall Steam Station. The initial technical memorandum titled Data Gap Evaluation Work
Plan - Marshall Steam Station describing groundwater and soil assessment activities for the
Marshall Steam Station additional source areas (e.g. PV Structural Fill and ILF subgrade Structural
Fill) was submitted to the DEQ Mooresville Regional Office (MRO) on November 14, 2018. This
version of the plan was subsequently conditionally approved by the Division's Mooresville
Regional Office on December 3, 2018. Duke Energy then submitted the Data Gap Evaluation
Work Plan (REV 1) on December 7, 2018 that incorporated those conditions. The objective of the
proposed Data Gap Evaluation Work Plan (REV 2) is to install one additional bedrock
groundwater monitoring well for vertical delineation east of the PV structural fill, as requested by
the Division's MRO, at existing well cluster PVSF-2.
The Division has reviewed and hereby approves the proposed assessment activities under the
condition that the results are reported in the upcoming revised Corrective Action Plan (CAP).
If applicable, the results should also be incorporated into the revised geochemical and groundwater
fate and transport models for the site. If the results of the modeling show current or future impacts
to groundwater and/or surface water from this area, then appropriate remedial strategies shall be
proposed in the revised CAP.
North Carolina Department of Environmental Quality 1 Division of Water Resources
RE � 512 North Salisbury Street 1 1636 Mail Service Center Raleigh, North Carolina 27699-1636
919.707.9000

If you have any questions, please contact Brandy Costner (Mooresville Regional Office) at (704)
235-2185 or Steve Lanter (Central Office) at [phone].
Sincerely,
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Jim Gregson, Deputy Director
Division of Water Resources
cc: MRO WQROS Regional Office
WQROS Central File Copy