NC0003468_Other Correspondence_20190115

DUKE
•�, ENERGY.
January 15, 2019
Mr. Jeffrey Poupart, Section Chief
NC Division of Water Resources
1617 Mail Service Center
Raleigh, NC 27699-1617
RECEIVED/DENWDWR
JA N 31 2019
Water Resources
Permitting Section
Subject: Dan River Combined Cycle
Request for use of Chemicals in the Dewatering Treatment Process
Amendment to existing NPDES permit renewal application
NC0003468
Rockingham County
Dear Mr. Poupart,
Dan River Combined Cycle
Duke Energy Carolinas
900 South Edgewood Road
Eden, NC 27288
As requested and approved previously in our Dan River Combined Cycle Station Renewal Package dated July 2016,
Duke Energy (Duke) submits this letter to amend our existing NPDES application under which the plant currently
operates. The amendment is to disclose the use of hydrochloric acid for use for pH adjustment in the dewatering
treatment system. An updated list of chemicals is attached. Please include this with the relevant permit files.
Based on discussion, it is our understanding that with this modification to the existing permit application, no permit
modification would be necessary and Duke is authorized to utilize these additives to assure compliance with NPDES
permit limits and keep the dewatering system operational.
If you have any questions regarding this letter, please contact Mrs. Joyce Dishmon at [phone] or
ioyce.dishmonCaduke-energycom.
I certify under penalty of law, that this document and all attachments were prepared under my direction or
supervision in accordance with a system designed to assure that qualified personnel properly gather and
evaluate the information submitted. Based on my inquiry of the person or persons who manage the system,
or those persons directly responsible for gathering the information, the information submitted is, to the best
of my knowledge and belief, true, accurate, and complete. I am aware that there are significant penalties
for submitting false information, including the possibility of fines and imprisonment for knowing violations
Sincerely,
�
Michael Lanning�
GM II — Regulated Stations
Dan River Combined Cycle
Attachment
Cc: Sherri Knight, W/S Regional Office, 450 W. Hanes Mill Rd, Suite 300, Winston-Salem, NC 27105
Joyce Dishmon/Filenet, Sr Env Specialist
Dana Newcomb, Lead EHS Field Support
Shannon Langley, Principle

Form 2C — Item VI Potential Discharges Not Covered by Analysis
Location
Chemical
Quantity
Frequency
Purpose
Water treatment
60% Ferric
5000 gal tank
As needed
Coagulant
(Clarifier)
Sulfate/Ferralyte 8130
Water Treatment
25% Sodium
3000 gal tank
As Needed
pH control
(Clarifier)
Hydroxide
Water Treatment
12.5% Sodium
6000 gal tank
As Needed
disinfection
(Clarifier)
Hypochlorite
Water Treatment
Nalclear 7768
400 gal tote
As Needed
Flocculant
(Clarifier and Thickener
Tank)
Water Treatment
Ferralyte 8130
5000 gal tank
As Needed
Flocculant
(Clarifier and
Thickener Tank)
Water Treatment
PolyClean 7
5 gal pails
As Needed
Polymer pump
(Polymer Pumps)
cleaning solution
Cooling Tower
31) Trasar 3DT187
2000 gals tank
As needed
Dispersant/corrosion
(shared with Chiller
inhibitor
Tower)
Cooling Tower
12.5% Sodium
6000 gals tank
As needed
Disinfection/biological
(shared with Chiller
Hypochlorite
growth control
Tower)
Cooling Tower
Trasar 3DT199
110 gal tote
As needed
Corrosion inhibitor
(shared with Chiller
Tower)
Cooling Tower
Nalco 7468
5 gal pails
As needed
Defoamer
Chiller System
DOWFROST HD
63000 gals
Circulated,
Cooling Agent
(propylene glycol)
(system)
closed system
Chiller System
Dupont SUVA 123
2000 gals
Circulate,
Refrigerant
closed system
Chiller System
NalPrep IV
200 gals
1/year
Layup Chemical
Closed Cooling Water
33% Propylene
21000 gals
As needed
Cooling Agent
Glycol
(system)
Closed Cooling Water
Nalco C-4710
5 gal pail
As needed
Corrosion Inhibitor
Demineralizer Bldg
38% Sodium
330 gal tote
As needed
Dechlorination
(RO and Cooling Tower
bisulfite
Blow down)
Demineralizer Bldg
25% Sodium
330 gal tote
As needed
pH control
(RO system)
hydroxide
Demineralizer Bldg
50% Citric acid
350 gal tote
As needed
OF acid cleaning
(UF system)
Demineralizer Bldg (UF
12.5% sodium
330 gal tote
As needed
OF bleach cleaning
system)
hypochlorite
Demineralizer Bldg
AntiscalantPC-
110 gal tote
As needed
Corrosion inhibitor
(RO system)
191T
Demineralizer Bldg
RoCide DB20
150 ml
1/quarter or as
Biocide
(RO cleaning biocide)
needed
Demineralizer Bldg
RoClean P303
96 Ibs
1/quarter or as
RO acid cleaning
(RO cleaning)
needed
Demineralizer Bldg
RoCide IS2
1/quarter or as
Biocide
(RO cleaning)
needed

Demineralizer Bldg
RoClean P111
96 Ibs
1/quarter or as
RO caustic cleaning
(RO cleaning)
needed
Aux Boiler Bldg
19% Aqueous
330 gal tote
As needed
pH control
(HRSG Water)
Ammonia
Aux Boiler Bldg
Eliminox
75 gal tote
As needed
Oxygen scavenger
(HRSG Water)
Unit 9 HRSG phosphate
Trisodium
300 gal tank
As needed
Corrosion Inhibitor
skid
phosphate
(HRSG Water)
Unit 8 HRSG phosphate
Trisodium
300 gal tank
As needed
Corrosion Inhibitor
skid
phosphate
(HRSG water)
Steam Turbine Bldg
19% Aqueous
350 gal tote
As needed
pH control
(HRSG Water)
ammonia
Selective Catalytic
19% Aqueous
20000 gal tank
As needed
NOx emissions
Reduction
ammonia
reduction
Treated Domestic
Bio-sanitizer
135 Ibs
As needed
Disinfection/biological
Sewage
Tablets
growth control
(Calcium
Hypochlorite)
Ash Basin
25-50% Sodium
250 gal tote
As needed
pH control
hydroxide
Ash Basin
Sulfuric Acid
250 gal tote
As needed
pH control
Ash Basin
Compressed CO2
Cylinders I
As needed
pH control
Ash Basin
Hydrochloric Acid
250 gal tote
As needed
pH control