NC0005088_RE External Duke Energy Pump Test at Cliffside Allen and Marshall_20180502

Strickland, Bev
From: Smith, Eric G
Sent: Wednesday, May 02, 2018 12:41 PM
To: 'Toepfer, John R'
Cc: Pruett, Jeremy J.; Sullivan, Ed M; Czop, Ryan; Hardin, Tyler; Sheetz, Bryson; Bristol
Grohol; Witt, Kimberlee; Martin, Melonie Y; Courtney Murphy
([e-mail]); Langley, Shannon; Ogallo, LeToya Fields; Cahoon,
Steve; Julie Robertson; DAHLE, TIMOTHY; Armstrong, Larry -smeinc; Webb, Kathy -
synterracorp; Lanter, Steven; Zimmerman, Jay; Watts, Debra; Campbell, Ted; Davidson,
Landon; Costner, Brandy F; Harbison, Joanna A; Pitner, Andrew
Subject: RE: [External] Duke Energy Pump Test at Cliffside, Allen and Marshall
John
Per your request below (dated April 30, 2018), DWR supports installing aquifer pump test wells and observation wells
within and below the ash basins under the following conditions:
Prior to installation and operation of the wells, Duke must submit an aquifer test plan (similar to the one
submitted for the Asheville Steam Electric Plant) to the applicable regional office for review and comment that
details the following (at a minimum):
o Rationale for the pump test
o Data to be collected
o Methodology
o Well construction diagrams and schematics showing the locations of the pumping wells, observation
wells, and where the extracted water will be routed and disposed
o Description of how the wells will be used or abandoned following completion of the test.
• DWR will not support pumping or observation wells that are partially screened in both ash and underlying
soil. The wells must either be wholly screened in the ash basin or the underlying soil. If a well penetrates the
bottom of the ash basin, it must be cased and grouted to minimize connection between the ash basin and
underlying material. Duke has indicated that Type 3 wells will be installed beneath the ash basin and into
underlying material.
• Duke shall confirm with the NPDES Permitting Staff prior to initiating pumping that the test will conform to all
requirements of the NPDES Permit.
• Any deviation in well construction will require submittal of a variance to the applicable regional office for
approval. Per our April 27, 2018 email, as long as the pumping or observation "wells" are screened wholly
within the ash and do not penetrate the bottom of the ash basin, the well construction requirements pursuant
to 15A NCAC 02C.0100 will not apply.
• Duke has indicated that the pumping wells (singularly or in combination) will not exceed 100,000 gallons/day.
• Duke has indicated that the extracted water will remain in the ash basins.
-Eric G. Smith
Eric G. Smith
Program Consultant
Division of Water Resources
Water Quality Regional Operations Section
Animal Feeding Operations & Groundwater Protection Branch

Department of Environmental Quality
919 807 6407 office
[e-mail]
512 N. Salisbury St
1636 Mail Service Center
Raleigh, NC 27699-1636
Email correspondence to and from this address is subject to the
North Carolina Public Records Law and may be disclosed to third parties.
From: Toepfer, John R [mailto:[e-mail]]
Sent: Monday, April 30, 2018 2:24 PM
To: Smith, Eric G <[e-mail]>
Cc: Pruett, Jeremy J. <[e-mail]>; Sullivan, Ed M <[e-mail]>; Czop, Ryan
<[e-mail]>; Hardin, Tyler <[e-mail]>; Sheetz, Bryson
<[e-mail]>; Bristol Grohol <[e-mail]>; Witt, Kimberlee
<[e-mail]>; Martin, Melonie Y <Melonie.Marti [e-mail]>; Courtney Murphy
([e-mail]) <[e-mail]>; Langley, Shannon <Shannon.Langley@duke-
energy.com>; Ogallo, LeToya Fields <[e-mail]>; Cahoon, Steve <Steve.Cahoon@duke-
energy.com>; Julie Robertson <[e-mail]>; DAHLE, TIMOTHY <[e-mail]>;
Armstrong, Larry -smeinc <[e-mail]>; Webb, Kathy -synterracorp <[e-mail]>; Lanter,
Steven <[e-mail]>
Subject: [External] Duke Energy Pump Test at Cliffside, Allen and Marshall
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Eric — per my call to you earlier today, Duke Energy is in the field installing wells for pump tests at the 3 sites noted
above in the subject line. The number and type of wells are shown in the attached pdf. Please note, all wells are type 3
wells for installation beneath ash into saprolite.
As I discussed with you, the pump test wells are not for "dewatering" (therefore, separate from your email guidance
from 04/27/18 (below)) and instead are for aquifer characterization. Information gathered during aquifer pumping tests
will be used to further refine the groundwater flow and transport model. The groundwater flow and transport model
will be used to determine contaminant migration pathways, potential remedial alternative responses and potential long
term impacts to groundwater in the vicinity of each site. It is important that hydraulic characteristics of the source area
(ash basin) and underlying strata (saprolite) are verified. Small variations in transmissivity and hydraulic conductivity
could result in large errors in long term impacts and potential remedial options.
It is currently anticipated that each of the proposed tests in both the ash and the saprolite will last three days (72
hours). Based on field observations from the first two sites (Marshall and Allen), anticipated flow rates will be less than
10 gallons per minute (gpm) from the pump test wells. Maximum total daily flows will be less than 14,400 gallons per
day (gpd) per well. A maximum of two wells will be running at any given time, resulting in a total daily flows of
approximately 30,000 gpd. Well less than 100,000 gpd noted as the permitting threshold.

The water from the pumping tests will remain in the ash basin. Duke Energy respectfully requests a quick review by DEQ
for concurrence we can use the saprolite wells AND ash basin wells for the pumping tests. Please let me know of
questions. thanks
John R. Toepfer, P.E.
Duke Energy
Lead Engineer
410 S. Wilmington Street/NC15
Raleigh, NC 27601
919-546-7863 phone
919-632-3714 cell
919-546-3669 fax
From: Smith, Eric G[mailto:eric.a.smith(a)ncdenr.Qov]
Sent: Friday, April 27, 2018 2:37 PM
To: Toepfer, John R
Cc: Pruett, Jeremy J.; Sullivan, Ed M; Czop, Ryan; Hardin, Tyler; Sheetz, Bryson; Grohol, Bristol; Witt, Kimberlee; Martin,
Melonie Y; Courtney Murphy (cmurphy a synterracorp.com); Langley, Shannon; Ogallo, LeToya Fields; Cahoon, Steve;
Campbell, Ted; Davidson, Landon; White, Kenneth B; Allen, Trent; Costner, Brandy F; Pitner, Andrew; Rice, Eric; Bolich,
Rick; Hart, William; May, David; Kegley, Geoff; King, Morella s; Wang, Shuying; Knight, Sherri; Zimmerman, Jay; Watts,
Debra; Lanter, Steven; Chernikov, Sergei; Grzyb, Julie; Poupart, Jeff; Risgaard, Jon
Subject: RE: [External] Extraction Well Questions - Ash Basin Pore Water
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John:
The following are DEQ's responses (in red) to your questions concerning "dewatering" wells:
1. If dewatering wells are fully screened within the ash basin, Duke Energy does not need a permit from NCDEQ
Division of Water Resources as long as the movement of water within the ash basin is in compliance with
existing NPDES permit no matter quantity of water removed per day. DEQ agrees that permits are NOT needed
for the construction or operation of these dewatering points as long as they are screened within ash and DO
NOT penetrate the bottom of the basin. Also we believe that, as long as the dewatering points are screened
within the ash and do not penetrate the bottom of the ash basin, the well construction requirements pursuant
to 15A NCAC 02C.0100 will not apply. Prior to beginning dewatering, Duke shall confirm with the NPDES
Permitting Staff that the dewatering activities will conform to all requirements of the NPDES Permit.
2. If dewatering wells are screened wholly or in part into soils beneath the ash basins, Duke Energy would need a
permit from NCDEQ Division of Water Resources if the system in total removed greater than 100K gallons of
water per day. This assumes the well(s) meets DEQ 2C regulations. If not, a variance from 2C regulations would
be required or the well(s) needs to be re -designed to meet 2C regulations. DEQ will NOT support the installation
of any dewatering point that penetrates the bottom of the ash basin as it may facilitate the movement of
contaminants into the underlying groundwater.
3. If dewatering wells are screened wholly or in part into soils beneath the ash basins, Duke Energy would NOT
need a permit from NCDEQ Division of Water Resources if the system in total removed less than 100K gallons of
water per day. This assumes the well(s) meets DEQ 2C regulations. If not, a variance from 2C regulations would
be required for the well(s) only if they are not re -designed to meet 2C regulations. As stated above, DEQ will

NOT support the installation of any dewatering point that penetrates the bottom of the ash basin as it may
facilitate the movement of contaminants into the underlying groundwater.
4. If a site already has a permit from DEQ as the site removes greater than 100K gallons per day, does DEQ require
an application if the system is screened beneath the ash and the system will remove greater than 100K gallons
per day? As stated above, no permits (therefore no associated applications or variances) will be required to
construct or operate the dewatering points as long as they are screened within ash and DO NOT penetrate the
bottom of the ash basin. Again, prior to beginning dewatering, Duke shall confirm with the NPDES Permitting
Staff that the dewatering activities will conform to all requirements of the NPDES Permit.
If you have any questions, please contact Jay Zimmerman, the applicable Regional Office Staff, or the NPDES Permitting
Staff.
-Eric G. Smith
Eric G. Smith
Program Consultant
Division of Water Resources
Water Quality Regional Operations Section
Animal Feeding Operations & Groundwater Protection Branch
Department of Environmental Quality
919 807 6407 office
eric.g.smitha_ncdenr.gov
512 N. Salisbury St
1636 Mail Service Center
Raleigh, NC 27699-1636
i% NothingCompares---,
Email correspondence to and from this address is subject to the
North Carolina Public Records Law and may be disclosed to third parties.
From: Toepfer, John R [mailto:[e-mail]]
Sent: Friday, March 09, 2018 10:37 AM
To: Smith, Eric G <[e-mail]>; Lanter, Steven <[e-mail]>
Cc: Pruett, Jeremy J. <[e-mail]>; Sullivan, Ed M <[e-mail]>; Czop, Ryan
<[e-mail]>; Hardin, Tyler <[e-mail]>; Sheetz, Bryson
<[e-mail]>; Bristol Grohol <[e-mail]>; Witt, Kimberlee
<[e-mail]>; Martin, Melonie Y <[e-mail]>; Courtney Murphy
([e-mail]) <[e-mail]>; Langley, Shannon <Shannon.Langley@duke-
energy.com>; Ogallo, LeToya Fields <[e-mail]>; Cahoon, Steve <Steve.Cahoon@duke-
energy.com>
Subject: [External] Extraction Well Questions - Ash Basin Pore Water
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Report Spam.

Eric and Steve — attached is an example cross section of an extraction well. Per a prior call with you, DEQ requested an
email with Duke's questions regarding dewatering ash basin pore water at various sites in NC. Items I would like to
discuss on a future call would be:
1. If dewatering wells are fully screened within the ash basin, Duke Energy does not need a permit from NCDEQ
Division of Water Resources as long as the movement of water within the ash basin is in compliance with
existing NPDES permit no matter quantity of water removed per day.
2. If dewatering wells are screened wholly or in part into soils beneath the ash basins, Duke Energy would need a
permit from NCDEQ Division of Water Resources if the system in total removed greater than 100K gallons of
water per day. This assumes the well(s) meets DEQ 2C regulations. If not, a variance from 2C regulations would
be required or the well(s) needs to be re -designed to meet 2C regulations.
3. If dewatering wells are screened wholly or in part into soils beneath the ash basins, Duke Energy would NOT
need a permit from NCDEQ Division of Water Resources if the system in total removed less than 100K gallons of
water per day. This assumes the well(s) meets DEQ 2C regulations. If not, a variance from 2C regulations would
be required for the well(s) only if they are not re -designed to meet 2C regulations.
4. If a site already has a permit from DEQ as the site removes greater than 100K gallons per day, does DEQ require
an application if the system is screened beneath the ash and the system will remove greater than 100K gallons
per day?
I would like to run through these and other questions you have on our next call. thanks
John R. Toepfer, P.E.
Duke Energy
Lead Engineer
410 S. Wilmington Street/NC15
Raleigh, NC 27601
919-546-7863 phone
919-632-3714 cell
919-546-3669 fax