NCS000546_MONITORING REPORT_20210115

AKE
P ENERGY
January 13, 2021
NCDEQ, Mooresville Regional Office
Attn: DEMLR Stormwater Program
610 East Center Ave., Suite 301
Mooresville, N.C. 28115
Subject: Duke Energy Carolinas, LLC
NPDES Storm Water Discharge Monitoring Report for:
Allen Steam Station — NCS000546 — Gaston County
Allen Steam Station
253 Plant Allen Rd.
Belmont, NC 28012
704 829-2587
RECEIVED
JAN 15 2021
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In accordance with Part III, E(2) of the above referenced NPDES Storm Water permit, the original and one
copy of the monthly monitoring reports are attached. The samples collected are required monthly due to
Tier Two or Tier Three Status. The period for sampling ended December 31, 2020. Samples were collected
for the period at outfalls SW007, SW009, SW010, SW016, SW018 and SW020 on December 14, 2020.
The laboratory analysis results were received on December 29, 2020. Duke Energy has performed the
steps required by the Tier II and Tier III for these outfalls. There was no sample collected at outfalls SW001,
SWO13-10 and SW013-13 for the period, due to No Qualifying Flow condition.
Outfalls SW002, SWO08 and SW015 were sampled on December 14, 2020 and the analysis results are
included on this DMR. This DMR also contains the NO FLOW status of outfalls during the period of October
1, 2020 through December 31, 2020.
Analytes sampled above the benchmark values for analytical monitoring are as follows.
Outfall
Parameter
Result
Benchmark
SWO07
Zinc
0.283 mg/L
0.126 mg/L
SW010
Copper
0.0104 mg/L
0.010 mg/L
SW020
TSS
2200 mg/L
100 mg/L
W020
Copper
0.288 mg/L
0.010 mg/L
W020
Zinc
0.395 mg/L
0.126 mg/L
All values reported on the attached reports are dependent on the accuracy of approved analytical methods
used to measure parameters.

Please direct any correspondence or questions concerning the Allen Steam Station NPDES Storm Water
Program to Elizabeth Glenn [phone] or Randy Gantt [phone].
Yours truly,
Rick R. Roper, General Manager III
Allen Steam Station
Duke Energy Carolinas, LLC
Attachments
be: w/attachment Elizabeth Glenn
UPS Tracking: 1Z X67 601 42 9293 1283

STORMWATER DISCHARGE OUTFALL (SDO)
MONITORING REPORT
Permit Number NCS000546
FACILITY NAME Allen Steam Station
PERSON COLLECTING SAMPLE(S) Josh Sexton/Steve Hamilton
CERTIFIED LABORATORY(S) Duke Energy Carolinas, LC Lab # 248
Pace Analytical Services Lab #329
Part A: Specific Monitoring Requirements
SAMPLES COLLECTED DURING CALENDAR YEAR: 2020
(This monitoring report shall be received by the Division no later than 30 days from
the date the facility receives the sampling results from the laboratory.)
e_ 1
COUNTY Gaston
a
PHONE NO. ( 704 ) 860-4945
Cdt
ev `-
SIGNATURE OF PERMITTEE OR DESIGNEE
REQUIRED ON PAGE 4.
Outfall
Date
50050
00400
01077
01002
01022
01012
01027
No.
Sample
Collected
Total
Flow (if app.)
Total
Rainfall
pH
Silver, Total (as
A)
Arsenic, Total
(as As)
Boron, Total
(as B)
Beryllium,
Total (as Be)
Cadmium,
Total (as Cd)
mo/dd/yr
MG
inches
m
m
m
mg1L
m
SW001
N/A
N/A
NO QUALIFYING FLOW FOR THE MONTH OF DECEMBER 2020
SWOOIA
N/A
N/A
NO QUALIFYING FLOW FOR OCTOBER 1, 2020 - DECEMBER 31, 2020
SW002
12/14/20
N/A
0.43 17.6 1 <0.0002 1 <0.001 1 <0.05 <0.001 <0.001
SW003
N/A
N/A
NO QUALIFYING FLOW FOR OCTOBER 1, 2020 - DECEMBER 31, 2020
SW005
N/A
/A
NO QUALIFYING FLOW FOR OCTOBER 1, 2020 - DECEMBER 31, 2020
SW007
12/14/20
/A
0.43
7.6
<0.0002
<0.001
<0.05
<0.001
<0.001
SW008
12/14/20
N/A
0.43
7.7
<0.0002
<0.001
<0.05
<0.001
<0.001
SW009
12/14/20
N/A
0.43
7.4
<0.0002
0.00179
<0.05
<0.001
<0.001
SW010
12/14/20
N/A
0.43
7.2
<0.0002
0.00399
<0.05
<0.001
<0.001
SW013-07
N/A
/A
NO QUALIFYING FLOW FOR OCTOBER 1, 2020 - DECEMBER 31, 2020
SW013.08
N/A
N/A
NO QUALIFYING FLOW FOR OCTOBER 1, 2020 - DECEMBER 31, 2020
SW013-09
N/A
N/A
NO QUALIFYING FLOW FOR OCTOBER 1, 2020 - DECEMBER 31, 2020
SW013.10
N/A
N/A
NO QUALIFYING FLOW FOR THE MONTH OF DECEMBER 2020
SW013-11
N/A
N/A
NO QUALIFYING FLOW FOR OCTOBER 1, 2020 - DECEMBER 31, 2020
SW013-12
N/A
N/A
NO QUALIFYING FLOW FOR OCTOBER 1, 2020 - DECEMBER 31, 2020
SW013.13
N/A
/A
NO QUALIFYING FLOW FOR THE MONTH OF DECEMBER 2020
SW013-14
N/A
/A
NO QUALIFYING FLOW FOR OCTOBER 1, 2020 - DECEMBER 31, 2020
SW013-15
N/A
N/A
NO UALIFYING FLOW FOR OCTOBER 1, 2020 -DECEMBER 31, 2020
SWO15
12/14/20
N/A
0.43
17.5
1 <0.0002
10.0218
10.186
<0.001
I <11.1101
SW016
12/14/20
N/A
0.43
7.3
<0.0002
0.00106
<0.05
<0.001
<0.001
SW018
12/14/20
N/A
0.43
7.3
<0.0002
1 <0.001
<0.05
1 <0.001
<0.001
SW020
12/14/20
1 N/A
0.43
17.6
1 <0.0002
10.00277
1 <0.05
10.00344
1 <0.001
Permit Number NCS000546
Form SWU-247, last revised 61122015
Page 1 of 4

Outfall
No.
Date
Sample
Collected
01034
01042
01067
01051
01097
01147
01059
01092
Chromium,
total (as Cr)
Copper,
Total
(as Cu)
Nickel, Total
(as Ni)
Lead, Total (as
Pb)
Antimony,
Total (as Sb)
Selenium, Total
(as Se)
Thallium,
(Total as TI)
Zinc, Total (as
Zn)
mo/dd/yr
mg/L
mg/L
m
m
m
m
m
m
SW001
NIA
NO QUALIFYING
FLOW FOR THE MONTH OF
DECEMBER 2020
SWOOIA
NIA
NO QUALIFYING FLOW FOR OCTOBER 1, 2020 - DECEMBER 31, 2020
SWO02
12/14/20
<0.001 0.00526 0.00117 <0.001 <0.001 <0.001 <0.0002 10.055
SWO03
NIA
NO QUALIFYING FLOW FOR OCTOBER 1, 2020 - DECEMBER 31, 2020
SWO05
NIA
NO QUALIFYING
FLOW FOR OCTOBER 1, 2020
- DECEMBER 31, 2020
SWO07
12/14/20
<0.001
<0.001
<0.001
<0.001
<0.001
<0.001
<0.0002
0.283
SWO08
12/14/20
0.00103
0.00384
0.00122
<0.001
<0.001
<0.001
<0.0002
0.022
SWO09
12/14/20
0.00114
0.00398
0.00125
0.00270
<0.001
0.00471
<0.0002
0.105
SWO10
12/14/20
0.00408
0.0104
0.00694
10.00313
<0.001
10.00362
<0.0002
0.050
SWO13-07
N/A
NO QUALIFYING
FLOW FOR OCTOBER 1, 2020
- DECEMBER 31, 2020
SWO13-08
N/A
NO QUALIFYING FLOW FOR OCTOBER 1, 2020 - DECEMBER 31, 2020
SWO13-09
NIA
NO QUALIFYING FLOW FOR OCTOBER 1, 2020 - DECEMBER 31, 2020
SWO13-10
N/A
NO QUALIFYING FLOW FOR THE MONTH OF DECEMBER 2020
SWO13-11
N/A
NO QUALIFYING FLOW FOR OCTOBER 1, 2020 - DECEMBER 31, 2020
SWO13-12
N/A
NO QUALIFYING FLOW FOR OCTOBER 1, 2020 - DECEMBER 31, 2020
SWO13-13
N/A
NO QUALIFYING FLOW FOR THE MONTH OF DECEMBER 2020
SWO13-14
N/A
NO QUALIFYING FLOW FOR OCTOBER 1, 2020 - DECEMBER 31, 2020
SWO13-15
N/A
NO QUALIFYING
FLOW FOR OCTOBER 1, 2020
- DECEMBER
31, 2020
SWO15
12/14/20
<0.001
0.00115
0.00109
<0.001
<0.001
<0.001
<0.0002
<0.005
SWO16
12/14/20
0.00133
0.00181
<0.001
<0.001
<0.001
<0.001
<0.0002
0.070
SWO18
12/14/20
<0.001
0.00156
<0.001
<0.001
<0.001
<0.001
<0.0002
<0.005
SW020
12/14/20
10.0451
0.288
0.0520
10.020
<0.001
<0.001
0.000651
0.395
Permit Number NCS000546 Form SWU-247, last revised 611212015
Page 2 of 4

Outfall
No.
Date
Sample
Collected
71900
CO530
00556
Mercury, Total,
Method 1631E
Solids, Total
Suspended —
Concentration
Oil & Grease
mo/dd/yr
ng/L
mg/L
m
SW001
N/A
NO QUALIFYING FLOW FOR THE MONTH
OF DECEMBER 2020
SWO01A
N/A
NO QUALIFYING FLOW FOR OCTOBER 1, 2020 — DECEMBER 31,
2020
SW002
12/14/20
2.65 14.7
SW003
N/A
NO QUALIFYING FLOW FOR OCTOBER 1, 2020 — DECEMBER 31,
2020
SW005
N/A
NO QUALIFYING FLOW FOR OCTOBER 1, 2020 — DECEMBER 31,
2020
SW007
12/14/20
1.34
15
SW008
12/14/20
2.83
6.6
SWO09
12/14/20
3.01
10
SWO10
12/14/20
6.24
143
SW013-07
N/A
NO QUALIFYING FLOW FOR OCTOBER 1, 2020 — DECEMBER 31,
2020
SWO13-08
N/A
NO QUALIFYING FLOW FOR OCTOBER 1, 2020 — DECEMBER 31,
2020
SW013-09
N/A
NO QUALIFYING FLOW FOR OCTOBER 1, 2020 — DECEMBER 31,
2020
SW013-10
N/A
NO QUALIFYING FLOW FOR THE MONTH OF DECEMBER 2020
SW013-11
N/A
NO QUALIFYING FLOW FOR OCTOBER 1, 2020 — DECEMBER 31,
2020
SW013-12
N/A
NO QUALIFYING FLOW FOR OCTOBER 1, 2020 — DECEMBER 31,
2020
SWO13-13
N/A
NO QUALIFYING FLOW FOR THE MONTH OF DECEMBER 2020
SW013-14
N/A
NO QUALIFYING FLOW FOR OCTOBER 1, 2020 — DECEMBER 31,
2020
SWO13-15
N/A
NO QUALIFYING FLOW FOR OCTOBER 1, 2020 — DECEMBER 31,
2020
SWO15
12/14/20
2.75
5.4
SWO16
12/14/20
3.56
35
SWO18
12/14/20
2.74
15
<5
SWO20
12/14/20
13.6 Avg
2200
Avg — Average of primary and duplicate mercury samples for SW020 (13.8 ng/L and 13.4 ng/L = 13.6 ng/L).
Benchmark exceedances include Zinc at SW007 and SW020; Copper at SWO10 and SW020; TSS at SW020.
Note: The Hg result for outfall SW020 was 13.6 ng/L (average). This Hg value is above the 12 ng/L North Carolina water quality standard for mercury and is noted on this DMR
but does not trigger a Tier response.
Permit Number NCS000546 Form SWU-247, last revised 611212015
Page 3 of 4

Does this facility perform Vehicle Maintenance Activities using more than 55 gallons of new motor oil per month? O yes @ no
(if yes, complete Part B)
Part B: Vehicle Maintenance Activity MonitoringRe uirements
Outfall
No.
Date
Sample
Collected
50050
00556
00530
00400
Total Flow
(if applicable)
Total
Rainfall
Oil & Grease
(if appl.)
Non -polar
O&G/TPH
(Method 1664
SGT-HEM), if
appl.
Total
Suspended
Solids
pH
New Motor
Oil Usage
mo/dd/yr
MG
inches
mg/l
mg/l
unit
gal/mo
STORM EVENT CHARACTERISTICS:
Date 12/14/20
Total Event Precipitation (inches): 0.43
Event Duration (hours): (only if applicable —see permit.)
(if more than one storm event was sampled)
Date
Total Event Precipitation (inches):
Event Duration (hours): (only if applicable— see permit.)
Mail Original and one copy to:
Division of Energy Mineral and Land Resources
Attn: Central Files
1617 Mail Service Center
Raleigh, North Carolina 27699-1617
"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."
Wl i
(Signature of Permittee) ( te)
Permit Number NCS000546 Form SWU-247, last revised 611212015
Page 4 of 4