NCG120101_MONITORING INFO_20190122

STORMWATER DIVISION CODING SHEET
NCG PERMITS
PERMIT NO. I /V U& 107D I 0 I
DOC TYPE ❑HISTORICAL FILE
q�IIMONITORING REPORTS
DOC DATE ❑ C� O I � o / a- �-
YYYYMMDD

DUKE
ENERGY®
PROGRESS
File: Mayo 12520-R
NC Division of Water Resources
ATT NTION: Central Files
16171 Mail Service Center
Raleigh, North Carolina 27699-1617
[]E: FIVO�1I�12019
JAN222019
Mayo Steam Plant
Duke Energy Progress
10660 Boston Road
Roxboro, NC 27574
CEN i NAL FMCS
Subject: 15A N. C. Admin. Code 2B .0506 0WR SEC710�1
Mayo Electric Generating Plant
National Pollutant Discharge Elimination System (NPDES) Number NCG120101
Monofill Stormwater Discharge Outfall Monitoring Report
Dear Sir or Madam:
Please find enclosed the 2018 July- December semi-annual Monofill Stormwater Discharge Monitoring
Report, with comments, for Permit Number NCG120101, SDO 001, SDO 002 & SDO 003, for Duke
Energy Progress, LLC. The Mayo Electric Generating Plant Monofill became operational November 7,
2014.
I certif " under penalty of law, that this document and all attachments were prepared under illy 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. 1 am aware that there are significant penalties for submitting false information,
including the possibility of fines and imprisonment for knowing violations.
Please contact Mr. Lori Tollie at [phone], if there are any questions concerning the data in this
submittal.
Sincerely,
Tom Copol anager
Mayo Electric Generating Plant
Enclosures

Semi-annual Stormwater Discharge Monitoring Report
for North Carolina Division of Water Quality General Permit No. NCG120000
Date submitted
CERTIFICATE OF COVERAGE NO. NCG120101
FACILITY NAME Mayo Steam Plant Monofill
COUNTY Person
PERSON COLLECTING SAMPLES Heath Slade
LABORATORY Pace Lab Cert. # 667,633.40 & 12
Comments on sample collection or analysis: COC: does not require fecal
sampling_
Part A: Stormwater Benchmarks and Monitoring Results
SAMPLE COLLECTION YEAR 2018
SAMPLE PERIOD Dan -June ® July -Dec
or ❑ Monthly' (month)
DISCHARGING TO CLASS ❑ORW ❑HQW ❑Trout ❑PNA
[]Zero -flow ❑Water Supply [:]SA
❑X Other Bowes Branch Class C
PLEASE REMEMBER TO SIGN ON THE REVERSE 4
❑ No discharge this period?z
Outfafl No.
Date Sample
Collected'
(mo/dd/yr)
24-hour rainfall
amount,
inches
,
Chemical Oxygen Demand
Fecal Coliform
Total Suspended Solids
Benchmarks ==_>
_
-
120 mg/L
1000 count per 100 mL
100 mg/L
001
12/12/18CO15:10
14" Snow
<12.5
Comment
8.3
002
12/12/18@14:45
14" Snow
33.8
Comment
2.5
003
12/12/18@14:30
14" Snow
<12.5
Comment
14.6
1 Monthly sampling (instead of semi-annual) must begin with the second consecutive benchmark exceedance for the same parameter at the same outfall.
z For sampling periods with no discharge at any single outfall, you must still submit this discharge monitoring report with a checkmark here.
3The total precipitation must be recorded using data from an on -site rain gauge. Unattended sites may be eligible for a waiver of the rain gauge requirement.
4 See General Permit text, Table 3, identifying the especially sensitive receiving water classifications where the more protective benchmark applies.
Note: Results must be reported in numerical format. For example, do not report Below Detection Limit, BDL, <PQL, Non -detect, ND, or other similar non -
numerical format. When results are below the applicable limits, they must be reported in the format "<XX m L" where XX is the numerical value of the
detection limit, reporting limit, etc. in mg/L. Conversely, where fecal coliform results exceed the dilution upper limit, report the result as ">XX".
Note: If you report a sample value in excess of the benchmark, you must implement Tier 1, Tier 2, or Tier 3 responses. See General Permit text.
Permit Date: 11/1/2018-05/31/2021 SWU-248, last revised 10/25/2012
Page 1 of 5

Semi-annual Stormwater Discharge Monitoring Report
for North Carolina Division of Water Quality General Permit No. NCG120000
Date submitted
CERTIFICATE OF COVERAGE NO. NCG120101
FACILITY NAME Mayo Steam Plant Monofill
COUNTY Person
PERSON COLLECTING SAMPLES _Heath Slacle
LABORATORY Pace Lab Cert. # 667,633,40 & 12
Comments on sample collection or analysis:
Part A: Stormwater Benchmarks and Monitoring Results
SAMPLE COLLECTION YEAR 2018
SAMPLE PERIOD []Jan -June ® July -Dec
or ❑ Monthly' (month)
DISCHARGING TO CLASS ❑ORW ❑HQW ❑Trout ❑PNA
❑Zero -flow [:]WaterSupply ❑SA
X❑Other Bowes Branch Class C
PLEASE REMEMBER TO SIGN ON THE REVERSE 4
❑ No discharge this period?z
Outfall No.
Date Sample
Collected
(rno/dd/yr)
24-hour rainfall
amount,
inches3
Arsenic
Selenium
Boron
Benchmarks =__>
_
-
mg/L
mg/L
mg/L
001
12/12/18915:10
14" Snow
0.00032
<0.00031
0.0173
002
12/12/18914:45
14" Snow
0.00022
<0.00031
0.009
003
12/12/18@14:30
14" Snow
0.0025
0.00049
0.121
1 Monthly sampling (instead of semi-annual) must begin with the second consecutive benchmark exceedance for the same parameter at the same outfall.
2 For sampling periods with no discharge at any single outfall, you must still submit this discharge monitoring report with a checkmark here.
3The total precipitation must be recorded using data from an on -site rain gauge. Unattended sites may be eligible for a waiver of the rain gauge requirement.
See General Permit text, Table 3, identifying the especially sensitive receiving water classifications where the more protective benchmark applies.
Note: Results must be reported in numerical format. For example, do not report Below Detection Limit, BDL, <PQL, Non -detect, ND, or other similar non -
numerical format. When results are below the applicable limits, they must be reported in the format, "<XX mg[L", where XX is the numerical value of the
detection limit, reporting limit, etc. in mg/L. Conversely, where fecal coliform results exceed the dilution upper limit, report the result as ">XX".
Note: If you report a sample value in excess of the benchmark, you must implement Tier 1, Tier 2, or Tier 3 responses. See General Permit text.
Permit Date: 11/1/2018-05/31/2021 SWU-248, last revised 10/2S/2012
Page 2 of 5

Semi-annual Stormwater Discharge Monitoring Report
for North Carolina Division of Water Quality General Permit No. NCG120000
Date submitted
CERTIFICATE OF COVERAGE NO. NCG120101
FACILITY NAME Mayo Steam Plant Monofill
COUNTY Person
PERSON COLLECTING SAMPLES Heath Slade
LABORATORY Pace Lab Cert. # _667, 633, 40 & 12
Comments on sample collection or analysis:
Part A: Stormwater Benchmarks and Monitoring Results
SAMPLE COLLECTION YEAR 2018
SAMPLE PERIODDan-June ® July -Dec
or ❑ Monthly' (month)
DISCHARGING TO CLASS ❑ORW ❑HQW ❑Trout ❑PNA
❑Zero -flow ❑Water Supply []SA
X❑Other Bowes Branch Class C
PLEASE REMEMBER TO SIGN ON THE REVERSE -->
❑ No discharge this period?'
Outfall No.
Date Sample
Collected'
(mo/dd/yr)
24-hour rainfall
amount,
Inches3
PH
Conductivity
Benchmarks===>
_
-
S.U.
.S/m
001
12/12/18@15:10
14" Snow
6.52
0.0083
002
12/12/18@14:45
14" Snow
6.42
0.0074
003
12/12/18@14:30
14" Snow
7.33
0.0234
1 Monthly sampling (instead of semi-annual) must begin with the second consecutive benchmark exceedance for the same parameter at the same outfall.
2 For sampling periods with no discharge at any single outfall, you must still submit this discharge monitoring report with a checkmark here.
3The total precipitation must be recorded using data from an on -site rain gauge. Unattended sites may be eligible for a waiver of the rain gauge requirement.
° See General Permit text, Table 3, identifying the especially sensitive receiving water classifications where the more protective benchmark applies.
Note: Results must be reported in numerical format. For example, do not report Below Detection Limit, BDL, <PQL, Non -detect, ND, or other similar non -
numerical format. When results are below the applicable limits, they must be reported in the format, "<XX me/L", where XX is the numerical value of the
detection limit, reporting limit, etc. in mg/L. Conversely, where fecal coliform results exceed the dilution upper limit, report the result as ">XX".
Note: If you report a sample value in excess of the benchmark, you must implement Tier 1, Tier 2, or Tier 3 responses. See General Permit text.
Permit Date: 11/1/2018-05/31/2021 SWU-248, last revised 10/25/2012
Page 3 of 5

Semi-annual Stormwater Discharge Monitoring Report
Note: if you report a sample value in excess of the benchmark, you must implement Tier 1, Tier 2, or Tier 3 responses. See General Permit text.
Part B: Vehicle Maintenance Area Monitoring Results: only for facilities averaging > 55 gal of new oil per month.
❑ No discharge this period?'
Outfall No.
Date Sample
Collected'
(mo/dd/yr)
24-hour rainfall
amount,
Inches3
Non -polar O&G/TPH by
EPA 1664 (SGT-HEM)
Total Suspended Solids
pH
Benchmarks ===>
_
-
15 mg/L
100 mg/L or 50 mg/L
6.0 — 9.0 SU
Footnotes from Part A also apply to this Part B
Note: if you report a sample value in excess of the benchmark, you must implement Tier 1, Tier 2, or Tier 3 responses. See General Permit text.
FOR PART A AND PART B MONITORING RESULTS:
• A BENCHMARK EXCEEDANCE TRIGGERS TIER 1 REQUIREMENTS, SEE PERMIT PART II SECTION B.
+ 2 EXCEEDANCES IN A ROW FOR THE SAME PARAMETER AT THE SAME OUTFALL TRIGGER TIER 2 REQUIREMENTS. SEE PERMIT PART II SECTION B.
• TIER 3: HAS YOUR FACILITY HAD 4 OR MORE BENCHMARK EXCEEDENCES FOR THE SAME PARAMETER AT ANY ONE OUTFALL? YES ❑ NO®
IF YES, HAVE YOU CONTACTED THE DWQ REGIONAL OFFICE? YES ❑ NO ❑
REGIONAL OFFICE CONTACT NAME:
Mail an original and one copes this DMR including all "No Discharge" reports, within 30 days of receipt of the lab results (or at end of monitoring period
in the case of "No Discharge" reports) to:
Division of Water Quality
Attn: DWQ Central Files
1617 Mail Service Center
Raleigh, North Carolina 27699-1617
YOU MUST SIGN THIS CERTIFICATION FOR ANY INFORMATION REPORTED:
"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."
Permit Date: 11/1/2018-05/31/2021 SWU-248, last revised 10/2S/2012
Page 4 of 5

(Signature of
d 1 /1-
(Date)
Permit Date: 11/l/2018-05/31/2021 SWU-248, last revised 10/25/2012
Page 5 of 5

ROY COOPER
Governor
MICHAEL S. REGAN
Secretary
WILLIAM E. (TOBY) VINSON, JR.
Interim Director
Mr. Tom Copolo
Station Manager
Duke Energy Progress, LLC
10660 Boston Road
Roxboro, NC 27574
NORTH CAROLINA
Environmental Quality
November 6, 2018
Subject: General Permit No. NCG120000 -Renewal
Mayo Steam Plant Monofiil
COC No. NCG120101
�Fc�t` 1C�^�q Person County
Dear Mr. Copolo:
Please see the attached new°�Certificaf ,VCoverage (COC) No. NCG120101 for renewed coverage
under Storwater General Pe mrmit NCG 120000 for this facility. This permit is reissued pursuant to
the requirements of North Carolina General Statute 143-215.1 and the Memorandum of Agreement
between the state of North Carolina and the U.S. Environmental Protection Agency, dated October
15, 2007 (or as subsequently amended.)
We received the company's request for clarification on this COC renewal on September 13, 2018.
Renewed coverage under this General Permit is granted with the condition that the permittee
performs additional sampling requirements as outlined in the amended conditions to the COC. These
requirements are based on the material landfilled at this site. This COC requires you to sample each
SDO semi-annually for arsenic, selenium, boron, conductivity, and pH. This COC also does not
require fecal coliform monitoring. These monitoring parameters are based on the coal combustion
residual material stored, and on monitoring results from 2014 and 2017 that were submitted with the
request.
Duke Energy indicated it would request a modification to NPDES Industrial Permit No. NCS000580
for Mayo Electric Generating Plant to include stormwater discharges from the Mayo Monofill. The
Stormwater Program agrees a modification to that individual permit to include those discharges is
preferable to continued coverage under this General Permit. Because General Permit NCG 120000
expires on May 31, 2021—six months prior to the expiration of Mayo Plant's individual permit —our
staff can coordinate a permit modification with the renewal of the individual permit.
TM D E QW��
North Carolina Department of Environmental Quality I Division of Energy, Mineral and Land Resources
St2 North Salisbury Street 1 1612 Mail service Center I Raleigh. North Carolina 27699-1612
919.707.9200

The permittee is required to apply for renewal no later than 180 days (six months) before the
expiration of the Plant's individual permit NCS000580 (per Part III., Section B.): by July 1, 2021 in
this case. Because that date occurs after the General Permit expires, we advise the company to
request the modification and apply for renewal of NCS000580 by December 31, 2020. This date will
give Program staff the opportunity to renew and issue the permit before the COC for the Monofill
expires.
The General Permit authorizes discharges of stormwater, and it specifies your obligations with
respect to discharge controls, management, monitoring, and record keeping. Please review the new
permit to familiarize yourself with all changes in the reissued permit. Your facility has six (6) months
from receipt of the permit to update your Stormwater Pollution Prevention Plan (SPPP) to reflect any
new permit requirements. Enclosed is a copy of the NCG 120000 General Permit.
When does electronic DMR (eDMR) reporting start, and does it affect this permit?
Because this COC requires analytical monitoring, eDMR will affect you. We are working toward on -
boarding permittees with NPDES stormwater permits into the DEQ's eDMR system next
year. Permittees will receive notification when our eDMR system is ready for permit -holders to
register and begin reporting monitoring data electronically.
Your coverage under the General Permit is transferable only through the specific action of
DEM LR. This permit does not affect the legal requirements to obtain other permits which may be
required by the N.C. Department of Environmental Quality (DEQ), nor does it relieve the permittee
from responsibility for compliance with any other applicable federal, state, or local law, rule,
standard, ordinance, order, judgment, or decree.
If you have any questions concerning this permit, please contact Bethany Georgoulias at telephone
number [phone] or by email betliany.geor oulias a.ncdenr. og_v.
Sincerely, 6��11
for William E. (Toby) Vinson, Jr., P.E., CPM, Interim Director
Division of Energy, Mineral, and Land Resources
cc: Raleigh Regional Office/ Bill Denton
Stormwater Program Niles
Lori Tollie / Duke Energy (via e-mail)
DWR Central Files
ND_E
North Carolina Department of Environmental Quality I Division of Energy, Mineral and Land Resources
512 North Salisbury Street 1 1612 Mail Service Center I Raleigh, North Carolina 27699-1612
919.707.9200

r
STATE OF NORTH CAROLINA
DEPARTMENT OF ENVIRONMENTAL QUALITY
DIVISION OF ENERGY, MINERAL, AND LAND RESOURCES
GENERAL PERMIT NO. NCG120000
CERTIFICATE OF COVERAGE No. NCG120101
STORMWATER DISCHARGES
NATIONAL POLLUTANT DISCHARGE ELIMINATION SYSTEM
In compliance with the provision of North Carolina General Statute 143-215.1, other lawful
standards and regulations promulgated and adopted by the North Carolina Environmental
Management Commission, and the Federal Water Pollution Control Act, and the North
Carolina Administrative Code in NCAC 1SA 02H .0114(b)(1), as amended,
Duke Energy Progress, Inc.
is hereby authorized to discharge stormwater from a facility located at
Mayo Steam Electric Plant Monofill
10660 Boston Road
Roxboro
Person County
to receiving waters designated as Bowes Branch, a class C water in the Roanoke River
Basin, in accordance with the effluent limitations, monitoring requirements, and other
conditions set forth in Parts I, I1, III, and IV of General Permit No. NCG120000 as attached,
and as amended in pages 2-3 of this Certificate of Coverage.
Amended conditions
1. This Certificate of Coverage is an enforceable part of the permit.
2. In accordance with 15A NCAC 021-1.0114(b)(1), the monitoring program in Part 11
Section B Table 1 Analytical Monitoring Requirements of this permit is amended
as follows:

Table 1 Analytical Monitoring Requirements
Discharge
Characteristics
Units
Measurement Frequencyl
Sample
T e2
Sample
Location3
Chemical Oxygen Demand
mg/1
semi-annual
Grab
SDO
Fecal Coliform
# per 100 ml
not re uired
N/A
N/A
Total Suspended Solids
mg/1
semi-annual
Grab
SDO
Arsenic (As)5
mg/l
semi-annual
Grab
SDO
Selenium (Se)5
mg/l
semi-annual
Grab
SDO
Boron (B)5
mg/i
semi-annual
Grab
SDO
H5
S.U.
semi-annual
Grab
SDO
Conductivity
S m
semi-annual
Grab
SDO
Total Rainfa114
inches
semi-annual
Rain gauge
F t�Q5:
1 Measurement Frequency: Twice per year, during a measureable storm event.
z Sample collection must begin within the first 30 minutes of discharge and continue to all outfalls until
completed.
3 Sample Location: Samples shall be collected at each stormwater discharge outfall (SDO) unless
representative outfall status (ROS) has been granted by NC Division of Energy, Mineral, and Land
Resources (DEMLR). A copy of the DEMLR letter granting ROS must be kept on site. DEMLR's ROS letter
remains in effect through the subsequent reissuance of this permit and as long as the pertinent site
conditions and operations remain unchanged, unless the ROS letter provides for other conditions or
duration.
4 For each sampled measureable storm event the total precipitation must be recorded from an on -site rain
gauge. (Where isolated sites are unmanned for extended periods, a local rain gauge reading may he
substituted for an on -site gauge, upon prior DEMLR written approval.)
5 No benchmark applies for these parameters. However, levels above 0.34 mg/l As, 0.056 mg/l Se, or
outside a pH range of 6.0-9.0 S.0 should be noted on the Stormwater Data Monitoring Report (SDMR)
submitted to NC DEQ,
This Certificate of Coverage shall become effective November 1, 2018.
This Certificate of Coverage shall remao in effect for the duration of the General Permit.
for William E. (Toby) Vinson, Jr., P.E., CPM
Interim Director, Division of Energy, Mineral, and Land Resources
By the Authority of the Environmental Management Commission
2 I COC No. NCG120101
effective November 1, 2018

LOCATION MAP:
NCG120101
S
Map Scale 1:24, 000
Duke Energy Progress, Inc.
Mayo Steam Electric Plant Monofill
Latitude: 360 32' 00" N
Longitude: 78055' 21" W
County: Person
Receiving Stream: Bowes Branch
Stream Ciass: C
Sub -basin: 03-02-05 (Roanoke River Basin)
r� �..Up
lit
Facility Location

i DUKE
ENERGY,
PROGRESS
File: Mayo 12520-R
Mayo Steam Plant
Duke Energy Progress
10660 Boston Road
Roxboro, NC 27574
NC Division of Water Resources 05/28/2018
ATTENTION: Central Files RECENPO
1617 Mail Service Center i� is
Raleigh, North Carolina 27699-1617 JUN 0 4 7.oib
CENT11AL HLES
Subject: 15A N. C. Admin. Code 213.0506 DWR SECTICfi'
Mayo Electric Generating Plant
National Pollutant Discharge Elimination System (NPDES) Number NCG 120101
Monofill Stormwater Discharge Outfall Monitoring Report
Dear Sir or Madam:
Please find enclosed the 2018 January -June semi-annual Monofill Stormwater Discharge Monitoring
Report, with comments, for Permit Number NCG120101, SDO 001, SDO 002 & SDO 003, for Duke
Energy Progress, LLC. The Mayo Electric Generating Plant Monofill became operational November 7,
2014.
1 certify,, under penalty of law, that this document and all attachments were prepared under my direction or-
super•s,ision in accordance with a system designed to assure that qualified personnel properly gather and evaluate
the information submitted. Based on nny inquir7, of the person or persons who manage the system, or those persons
directly responsible fur 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 .signifrccurt penalties for submitting false information,
inchrding the possibility of fines and hnprisolunent for knowing violations.
Please contact Mr. Lori Tollie at [phone], if there are any questions concerning the data in this
submittal.
Sincerely,
V
Tom Copolo - Manager
Mayo Electric Generating Plant
Enclosures

Semi-annual Stormwater Discharge Monitoring Report
for North Carolina Division of Water Quality General Permit No. NCG120000
Date submitted 5 ! ? o h �
CERTIFICATE OF COVERAGE NO. NCG120101
FACILITY NAME Mayo Steam Plant Monofill
COUNTY Person
PERSON COLLECTING SAMPLES Heath Slade
LABORATORY Pace Lab Cert. # 667 633
Comments on sample collection or analysis:
Part A: Stormwater Benchmarks and Monitoring Results
SAMPLE COLLECTION YEAR 2019
SAMPLE PERIOD X❑lan-June ❑ July -Dec
or ❑ Monthly'_ _ (month)
DISCHARGING TO CLASS ❑ORW ❑HQW ❑Trout ❑PNA
❑Zero -flow ❑Water Supply [:]SA
❑X Other Bowes Branch Class C
PLEASE REMEMBER TO SIGN ON THE REVERSE 4
❑ No discharge this period:
Outfall No.
Date Sample
Collected"
(mo/dd/yr)
24-hour rainfall
amount,
Inches3
Chemical Oxygen Demand
Fecal Conform
Total Suspended Solids
Benchmarks =__>
-
-
120 mg/L
1000 count per 100 ml.
100 mg/L
001
04/24/18 @ 10:45
1.02
14.0
117
13.6
002
04/24/18 @ 10:30
1.02
31.0
179
4.1
003
04/24/18 @ 10:15
1.02
21.0
933
33.5
1 Monthly sampling (instead of semi-annual) must begin with the second consecutive benchmark exceedance for the same parameter at the same outfall.
z For sampling periods with no discharge at any single outfall, you must still submit this discharge monitoring report with a checkmark here.
3The total precipitation must be recorded using data from an on -site rain gauge. Unattended sites may be eligible for a waiver of the rain gauge requirement.
4 See General Permit text, Table 3, identifying the especially sensitive receiving water classifications where the more protective benchmark applies.
Note: Results must be reported in numerical format. For example, do not report Below Detection Limit, BDL, <PQL, Non -detect, ND, or other similar non -
numerical format. When results are below the applicable limits, they must be reported in the format, "<XX mg/L" where XX is the numerical value of the
detection limit, reporting limit, etc. in mg/L. Conversely, where fecal coliform results exceed the dilution upper limit, report the result as ">XX".
Note: If you report a sample value in excess of the benchmark, you must implement Tier 1, Tier 2, or Tier 3 responses. See General Permit text.
.14
Permit Date: 11/1/2012-10/31/2017 SWU-248, last revised 10/25/2012
Page 1 of 5

Semi-annual Stormwater Discharge Monitoring Report
for North Carolina Division of Water Quality General Permit No. NCG120000
Date submitted . 5 I3c) i -�)GIV
CERTIFICATE OF COVERAGE NO. NCG120101
FACILITY NAME Mayo Steam Plant Monofill
COUNTY Person
PERSON COLLECTING SAMPLES Heath Slade
LABORATORY Pace I Lab Cert. # 667,633,40 & 12
Comments on sample collection or analysis:
Part A: Stormwater Benchmarks and Monitoring Results
SAMPLE COLLECTION YEAR 2018
SAMPLE PERIOD ® Jan -June ❑ July -Dec
or ❑ Monthly) (month)
DISCHARGING TO CLASS ❑ORW ❑HQW ❑Trout ❑PNA
❑Zero -flow [_]waterSupply ❑SA
❑X Other Bowes Branch Class C
PLEASE REMEMBER TO SIGN ON THE REVERSE -->
❑ No discharge this period?'
Outfali No.
Date Sample
1
Collected
(mo/dd/yr)
24-hour rainfall
amount,
inches 3
Arsenic
Selenium
Boron
Benchmarks =_->
-
-
mg/L
mg/L
mg/L
001
04/24/18 @10:45
1.02
0.0007
0.00027
0.261
002
04/24/18 @ 10:30
1.02
0.0005
<0.00017
0.028
003
04/24/18 @ 10:15
1.02
0.0049
0.00026
0.146
1 Monthly sampling (instead of semi-annual) must begin with the second consecutive benchmark exceedance for the same parameter at the same outfall.
z For sampling periods with no discharge at any single outfall, you must still submit this discharge monitoring report with a checkmark here.
3The total precipitation must be recorded using data from an on -site rain gauge. Unattended sites may be eligible for a waiver of the rain gauge requirement.
4 See General Permit text, Table 3, identifying the especially sensitive receiving water classifications where the more protective benchmark applies.
Note: Results must be reported in numerical format. For example, do not report Below Detection Limit, BDL, <PQL, Non -detect, ND, or other similar non -
numerical format. When results are below the applicable limits, they must be reported in the format. "<XX mg/L". where XX is the numerical value of the
detection limit, reporting limit, etc. in mg/L. Conversely, where fecal coliform results exceed the dilution upper limit, report the result as ">XX".
i Note: If you report a sample value in excess of the benchmark, you must implement Tier 1, Tier 2, or Tier 3 responses. See General permit text.
4
Permit Date: 11/1/2012-10/31/2017 SWU-248, last revised 10/25/2012
Page 2 of 5

DUKE
ENERGY®
PROGRESS
File: Mayo 12520-R
RECEIVED
DEC 0 7 2017
CENTRAL FILES
DWR SECTION
Mayo Steam Plant
Duke Energy Progress
10660 Boston Road
Roxboro, NC 27574
NC Division of Water Resources 1 1/28/2017
ATTENTION: Central Files
1617 Mail Service Center
Raleigh, North Carolina 27699-1617
Subject: 15A N. C. Admin. Code 213 .0506
Mayo Electric Generating Plant
National Pollutant Discharge Elimination System (NPDES) Number NCG120101
Monofill Stormwater Discharge Outfall Monitoring Report
Dear Sir or Madam:
Please find enclosed the 2017 July - December semi-annual Monofill Stormwater Discharge Monitoring
Report, with comments, for Permit Number NCG120101, SDO 001, SDO 002 & SDO 003, for Duke
Energy Progress, LLC, The Mayo Electric Generating Plant Monofill became operational November 7,
2014.
I certrfj,, under penalty of law, that this documew and all attachments were prepared under my direction or
supenlision 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 infornration, the information submitted is, to the hest 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 inrprisomnent for knowing violations.
Please contact Mr. Lori Tollie at [phone], if there are any questions concerning the data in this
submittal.
Sincerely,
�l
Tom Copolo - Manager
Mayo Electric Generating Plant
Enclosures

Semi-annual Stormwater Discharge Monitoring Report
for North Carolina Division of Water Quality General Permit No. NCG120000
Date submitted 11/27/2017
CERTIFICATE OF COVERAGE NO. NCG120101
FACILITY NAME Mayo Steam Plant Monofill
COUNTY Person
PERSON COLLECTING SAMPLES Heath Slade, Ronald Easley
LABORATORY _Pace_ Lab Cert. # 667, 633, 40 & 12
Comments on sample collection or analysis: SDO 002 & SDO 003 -
benchmark value for Fecal Coliform exceeded. Tier Two Response:
Monthly sampling.
Part A: Stormwater Benchmarks and Monitoring Results
SAMPLE COLLECTION YEAR 2017
SAMPLE PERIOD ❑ Jan -June ® July -Dec
or ❑ Monthly! (month)
DISCHARGING TO CLASS ❑ORW ❑HQW [—]Trout ❑PNA
[_]zero -flow ❑Water Supply []SA
®Other Bowes Branch Class C
PLEASE REMEMBER TO SIGN ON THE REVERSE 4
❑ No discharge this period?'
Outfall No.
Date Sample
Collected'
(mo/dd/yr)
24-hour rainfall
amount,
Inches3
Chemical Oxygen Demand
Fecal Coliform
Total Suspended Solids
Benchmarks =__>
_
-
120 mg/L
1000 count per 100 mL
100 mg/L or 50 mg/L
SDO 001
11/09/17@12:35
0.95
<12.5
520
23.9
SDO 002
11/09/17@12:15
0.95
25.0
3800
3.9
SDO 003
11/09/17@11:55
0.95
18.0
6000
10.7
1 Monthly sampling (instead of semi-annual) must begin with the second consecutive benchmark exceedance for the same parameter at the same outfall.
2 For sampling periods with no discharge at any single outfall, you must still submit this discharge monitoring report with a checkmark here.
3The total precipitation must be recorded using data from an on -site rain gauge. Unattended sites may be eligible for a waiver of the rain gauge requirement.
See General Permit text, Table 3, identifying the especially sensitive receiving water classifications where the more protective benchmark applies.
Note: Results must be reported in numerical format. For example, do not report Below Detection Limit, BDL, <PQL, Non -detect, ND, or other similar non -
numerical format. When results are below the applicable limits, they must be reported in the format, "<XX mg/L", where XX is the numerical value of the
detection limit, reporting limit, etc. in mg/L. Conversely, where fecal coliform results exceed the dilution upper limit, report the result as ">XX".
!Vote: if you report a sample value in excess of the benchmark, you must implement Tier 1, Tier 2, or Tier 3 responses. See General Permit text.
Permit Date: 11/1/2012-10/31/2017 5WU-248, last revised 10/25/2012
Page 1 of 5

Semi-annual Stormwater Discharge Monitoring Resort
for North Carolina Division of Water Quality General Permit No. NCG120000
Date submitted 11/27/2017
CERTIFICATE OF COVERAGE NO. NCG120101
FACILITY NAME Mayo Steam Plant Monofill
COUNTY Person
PERSON COLLECTING SAMPLES Heath Slade, Ronald Easley
LABORATORY_ Pace_ Lab Cert. # 667, 633, 40 & 12
Comments on sample collection or analysis:
Part A: Stormwater Benchmarks and Monitoring Results
SAMPLE COLLECTION YEAR 2017
SAMPLE PERIOD ❑ Jan -June ® July -Dec
or ❑ Monthly'_ _ (month)
DISCHARGING TO CLASS ❑ORW ❑HQW ❑Trout ❑PNA
❑Zero -flow ❑Water Supply ❑SA
®Other Bowes Branch Class C
PLEASE REMEMBER TO SIGN ON THE REVERSE 4
❑ No discharge this period?'
Outfall No.
Antimony
Total
Arsenic
Barium
Total
Beryllium
Total
Boron
Cadmium
Total
Chloride
Total
Chromium
Total
Units
mg/1
mg/I
mg/I
mg/I
mg/I
mg/I
mg/1
mg/I
Benchmarks ==_>
SDO 001
0.00075
0.0363
SDo 002
0.00055
0.0333
sDo 003
0.0025
0.0493
1 Monthly sampling (instead of semi-annual) must begin with the second consecutive benchmark exceedance for the same parameter at the same outfall.
2 For sampling periods with no discharge at any single outfall, you must still submit this discharge, monitoring report with a checkmark here.
3The total precipitation must be recorded using data from an on -site rain gauge. Unattended sites may be eligible for a waiver of the rain gauge requirement.
4 See General Permit text, Table 3, identifying the especially sensitive receiving water classifications where the more protective benchmark applies.
Note: Results must be reported in numerical format. For example, do not report Below Detection Limit, BDL, <PQL, Non -detect, ND, or other similar non -
numerical format. When results are below the applicable limits, they must be reported in the format, "<XX mg/L", where XX is the numerical value of the
detection limit, reporting limit, etc. in mg/L. Conversely, where fecal coliform results exceed the dilution upper limit, report the result as ">XX".
Note: If you report a sample value in excess of the benchmark, you must implement Tier 1, Tier 2, or Tier 3 responses. See General Permit text.
Permit Date: 11/1/2012-10/31/2017 SWU-248, last revised 10/25/2012
Page 2 of 5

Semi-annual Stormwater Discharge Monitoring Report
for North Carolina Division of Water Quality General Permit No. NCG120000
Date submitted 11/27/2017
CERTIFICATE OF COVERAGE NO. NCG120101
FACILITY NAME Mayo Steam Plant Monofill
COUNTY Person
PERSON COLLECTING SAMPLES Heath Slade, Ronald Easley
LABORATORY_ Pace_ Lab Cert. # 667, 633, 40 & 12
Comments on sample collection or analysis:
Part A: Stormwater Benchmarks and Monitoring Results
SAMPLE COLLECTION YEAR 2017
SAMPLE PERIOD ❑ Jan -June ® July -Dec
or ❑ Monthly' _ (month)
DISCHARGING TO CLASS ❑ORW ❑HQW ❑Trout ❑PNA
❑Zero -flow ❑Water Supply [:]SA
®Other Bowes Branch Class C
PLEASE REMEMBER TO SIGN ON THE REVERSE 4
❑ No discharge this period?z
Outfall No.
Conductivity
Copper
Total
Fluoride
Total
Hardness
Total
Lead
Total
Mercury
Total
Molybdenum
Total
Nickel
Total
Units
S/m
mg/I
mg/I
mg/I
mg/I
mg/I
mg/I
mg/I
Benchmarks ===>
SDO 001
0.00491
5130 002
0.0063
5130 003
0.00994
i Monthly sampling (instead of semi-annual) must begin with the second consecutive benchmark exceedance for the same parameter at the same outfall.
2For sampling periods with no discharge at any single outfall, you must still submit this discharge monitoring report with a checkmark here.
3The total precipitation must be recorded using data from an on -site rain gauge. Unattended sites may be eligible for a waiver of the rain gauge requirement.
See General Permit text, Table 3, identifying the especially sensitive receiving water classifications where the more protective benchmark applies.
Note: Results must be reported in numerical format. For example, do not report Below Detection Limit, BDL, <PQL, Non -detect, ND, or other similar non -
numerical format. When results are below the applicable limits, they must be reported in the format, "<XX m /L", where XX is the numerical value of the
detection limit, reporting limit, etc. in mg/L. Conversely, where fecal coliform results exceed the dilution upper limit, report the result as ">XX".
Note: If you report a sample value in excess of the benchmark, you must implement Tier 1, Tier 2, or Tier 3 responses. See General Permit text.
Permit Date: 11/1/2012-10/31/2017 SWU-248, last revised 10/25/2012
Page 3 of 5

Semi-annual Stormwater Discharge Monitoring Report
for North Carolina Division of Water Quality General Permit No. NCG120000
Date submitted 11/27/2017
CERTIFICATE OF COVERAGE NO. NCG120101
FACILITY NAME Mayo Steam Plant Monofill
COUNTY Person
PERSON COLLECTING SAMPLES Heath Slade, Ronald Easley
LABORATORY_ Pace_ Lab Cert. # 667, 633, 40 & 12
Comments on sample collection or analysis:
Part A: Stormwater Benchmarks and Monitoring Results
SAMPLE COLLECTION YEAR 2017
SAMPLE PERIOD ❑ Jan -June ® July -Dec
or ❑ monthly' month
DISCHARGING TO CLASS ❑ORW ❑HQW [—]Trout ❑PNA
❑Zero -flow ❑Water Supply []SA
®Other Bowes Branch Class C
PLEASE REMEMBER TO SIGN ON THE REVERSE -->
❑ No discharge this period?'
Outfall No.
pH
Selenium
Silver
Total
Sulfate
Total
Thallium
Total
Zinc
Total
Units
S.U.
mg/I
mg/I
mg/I
mg/I
mg/I
Benchmarks =_=>
SDO 001
7.41@16.2
0.00084
SDO 002
7.38@15.0
<0.00031
SDO 003
8.88@14.6
0.00071
1 Monthly sampling (instead of semi-annual) must begin with the second consecutive benchmark exceedance for the same parameter at the same outfall.
2 For sampling periods with no discharge at any single outfall, you must still submit this discharge monitoring report with a checkmark here.
3The total precipitation must be recorded using data from an on -site rain gauge. Unattended sites may be eligible for a waiver of the rain gauge requirement.
4 See General Permit text, Table 3, identifying the especially sensitive receiving water classifications where the more protective benchmark applies.
Note: Results must be reported in numerical format. For example, do not report Below Detection Limit, BDL, <PQL, Non -detect, ND, or other similar non -
numerical format. When results are below the applicable limits, they must be reported in the format "<XX m L" where XX is the numerical value of the
detection limit, reporting limit, etc. in mg/L. Conversely, where fecal coliform results exceed the dilution upper limit, report the result as ">XX".
Note: if you report a sample value in excess of the benchmark, you must implement Tier 1, Tier 2, or Tier 3 responses. See General Permit text.
Permit Date: 11/1/2012-10/31/2017 SWU-248, last revised 10/25/2012
Page 4 of 5

Part B: Vehicle Maintenance Area Monitoring Results: only for facilities averaging > 55 gal of new oil per month.
❑ No discharge this period:
Outfall No.
Date Sample
Collected'
(mo/dd/yr)
24-hour rainfall
amount,
Inches;
Non -polar O&G/TPH by
EPA 1664 (SGT-HEM)
Total Suspended Solids
pH
Benchmarks ===>
_
1S mg/L
100 mg/L or SO mg/L
6.0 — 9.0 SU
Footnotes from Part A also apply to this Part B
Note: If you report a sample value in excess of the benchmark, you must implement Tier 1, Tier 2, or Tier 3 responses. See General Permit text.
FOR PART A AND PART B MONITORING RESULTS:
• A BENCHMARK EXCEEDANCE TRIGGERS TIER 1 REQUIREMENTS. SEE PERMIT PART II SECTION B.
• 2 EXCEEDANCES IN A ROW FOR THE SAME PARAMETER AT THE SAME OUTFALL TRIGGER TIER 2 REQUIREMENTS. SEE PERMIT PART 11 SECTION B.
• TIER 3: HAS YOUR FACILITY HAD 4 OR MORE BENCHMARK EXCEEDENCES FOR THE SAME PARAMETER AT ANYONE OUTFALL? YES ❑ NO
IF YES, HAVE YOU CONTACTED THE DWQ REGIONAL OFFICE? YES ❑ NO ❑
REGIONAL OFFICE CONTACT NAME:
Mail an on inol and one copy of this DMR includin all "No Dischar e" reports, within 30 days of receipt of the lab results or at end of monitoring eriod
in the case of "No Discharge" reports) to:
Division of Water Quality
Attn: DWQ Central Files
1617 Mail Service Center
Raleigh, North Carolina 27699-1617
YOU MUST SIGN THIS CERTIFICATION FOR ANY INFORMATION REPORTED:
"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."
(Signature of Pe
19LO I l I-7
(Date)
Permit Date: 11/1/2012-10/31/2017 SWU-248, last revised 10/25/2012
Page 5 of 5

DUKE
Mayo Steam Plant
ENERGY.
PROGRESS
Duke Energy Progress
10660 Boston Road
Roxboro, NC 27574
File: Mayo 12520-R
NC Division of Water Resources 07/19/2017
ATTENTION: Central Files RECEIVED
1617 Mail Service Center R
Raleigh, North Carolina 27699-1617 JUL 2
6 2011
Subject: 15A N. C. Admin. Code 213.0506 CENTRAL FILES
Mayo Electric Generating Plant DWR SECTION
National Pollutant Discharge Elimination System (NPDES) Number NCG 120101
Monofill Stormwater Discharge Outfall Monitoring Report
Dear Sir or Madam:
Please find enclosed the 2017 January -,tune semi-annual Monofill Stormwater Discharge Monitoring
Report, with comments, for Permit Number NCG120101, SDO 001, SDO 002 & SDO 003, for Duke
Energy Progress, LLC. The Mayo Electric Generating Plant Monofill became operational November 7,
2014.
1 certify,, under penalty of law, that this document and all attachments were prepared under my direction or
superNsion in accordance with a system designed to assure that qualified personnel properly gather and evaluate
the information sir6nritted. Based on my ingrcin� of the person or persons tt!ho 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. 1 am aware that there are significant penalties for submitting false information,
including the possibility of fines and imprisonment for knowing violations.
Please contact Mr. Lori Tollie at [phone], if there are any questions concerning the data in this
submittal.
Sincerely,
lrlj
Tom Copolo - Manager
Mayo Electric Generating Plant
Enclosures

Semi-annual Stormwater Discharge Monitoring Report
for North Carolina Division of Water Quality General Permit No. NCG120000
Date submitted 07/19/2017
CERTIFICATE OF COVERAGE NO. NCG120101
FACILITY NAME Mayo Steam Plant Monofill
COUNTY Person
PERSON COLLECTING SAMPLES Heath Slade, Ronald Easley
LABORATORY _Pace_ Lab Cert. li 667, 633, 40 & 12
Comments on sample collection or analysis: SDO 002 - Fecal Coliforrr
analyzed out of hold time. SDO 002 & SDO 003 - benchmark value for
Fecal Coliform exceeded.
Part A: Stormwater Benchmarks and Monitoring Results
SAMPLE COLLECTION YEAR 2017
SAMPLE PERIOD ® Jan -June ❑ July -Dec
or ❑ Monthly' (month)
DISCHARGING TO CLASS ❑ORW ❑HQW ❑Trout ❑PNA
❑zero -flow []water Supply []SA
®Other Bowes Branch Class C
PLEASE REMEMBER TO SIGN ON THE REVERSE 4
El No discharge this period?2
Outfall No.
Date Sample
Collected'
(mo/dd/yr)
24-hour rainfall
amount,
inches'
Chemical Oxygen Demand
Fecal Coliform
Total Suspended Solids
Benchmarks ===>
-
-
120 mg/L
1000 count per 100 mL
100 mg/L or 50 mg/L°
SDO 001
06/19/17 @ 07:35
0.43
15.0
112
12.5
SDO 002
06/20/17 @ 07:12
1.53
21.0
41500
42.5
SDO 003
06/19/17 @ 07:10
0.43
52.0
12000
24.5
' Monthly sampling (instead of semi-annual) must begin with the second consecutive benchmark exceedance for the same parameter at the same outfall.
2 For sampling periods with no discharge at any single outfall, you must still submit this discharge monitoring report with a checkmark here.
3The total precipitation must be recorded using data from an on -site rain gauge. Unattended sites may be eligible for a waiver of the rain gauge requirement.
4 See General Permit text, Table 3, identifying the especially sensitive receiving water classifications where the more protective benchmark applies.
Note: Results must be reported in numerical format. For example, do not report Below Detection Limit, BDL, <PQL, Non -detect, ND, or other similar non -
numerical format. When results are below the applicable limits, they must be reported in the format, "<XX me/L",, where XX is the numerical value of the
detection limit, reporting limit, etc. in mg/L. Conversely, where fecal coliform results exceed the dilution upper limit, report the result as ">XX".
Note: If you report a sample value in excess of the benchmark, you must implement Tier 1, Tier 2, or Tier 3 responses. See General Permit text.
Permit Date: 11/1/2012-10/31/2017 SWU-248, last revised 10/25/2012
Page 1 of 5

Semi-annual Stormwater Discharge Monitoring Report
for North Carolina Division of Water Quality General Permit No. NCG120000
Date submitted 07/19/2017
CERTIFICATE OF COVERAGE No. NCG120101
FACILITY NAME Mayo Steam Plant Monofill
COUNTY Person
PERSON COLLECTING SAMPLES Heath Slade, Ronald Easley
LABORATORY_ Pace_ Lab Cert. # 667, 633, 40 & 12
Comments on sample collection or analysis:
Part A: Stormwater Benchmarks and Monitoring Results
SAMPLE COLLECTION YEAR 2017
SAMPLE PERIOD ® Jan -June ❑ July -Dec
or ❑ Monthly' fmonthJ
DISCHARGING TO CLASS ❑ORW ❑HQW ❑Trout ❑PNA
❑Zero -flow []WaterSupply ❑SA
®Other Bowes Branch Class C
PLEASE REMEMBER TO SIGN ON THE REVERSE 4
❑ No discharge this period:2
Outfall No.
Antimony
Total
Arsenic
Barium
Total
Beryllium
Total
Boron
Cadmium
Total
Chloride
Total
Chromium
Total
Units
mg/I
mg/I
mg/I
mg/I
mg/I
mg/I
mg/I
mg/I
Benchmarks ===>
SDO 001
<0.010
<0.004
0.0184
<0.001
<0.056
<0.005
3.5
0.0094
SDO 002
<0.010
<0.004
0.0211
<0.001
<0.056
<0.005
0.98
0.0126
SDO 003
<0.010
0.0054
0.0438
0.0013
<0.056
<0.005
5.9
<0.009
1 Monthly sampling (instead of semi-annual) must begin with the second consecutive benchmark exceedance for the same parameter at the same outfall.
2 For sampling periods with no discharge at any single outfall, you must still submit this discharge monitoring report with a checkmark here.
3The total precipitation must be recorded using data from an on -site rain gauge. Unattended sites may be eligible for a waiver of the rain gauge requirement.
4 See General Permit text, Table 3, identifying the especially sensitive receiving water classifications where the more protective benchmark applies.
Note: Results must be reported in numerical format. For example, do not report Below Detection Limit, BDL, <PQL, Non -detect, ND, or other similar non -
numerical format. When results are below the applicable limits, they, must be reported in the format,_"<XX m L", where XX is the numerical value of the
detection limit, reporting limit, etc. in mg/L. Conversely, where fecal coliform results exceed the dilution upper limit, report the result as ">XX".
Note: If you report a sample value in excess of the benchmark, you must implement Tier 1, Tier 2, or Tier 3 responses. See General Permit text.
Permit Date: 11/1/2012-10/31/2017 SWU-248, last revised 10/25/2012
Page 2 of 5

Semi-annual Stormwater Discharge Monitoring Report
for North Carolina Division of Water Quality General Permit No. NCG120000
Date submitted 07/19/2017
CERTIFICATE OF COVERAGE NO. NCG120101
FACILITY NAME Mayo Stearn Plant Monofill
COUNTY Person
PERSON COLLECTING SAMPLES Heath Slade, Ronald Easley
LABORATORY_ Pace_ Lab Cert. # 667, 633, 40 & 12
Comments on sample collection or analysis:
Part A: Stormwater Benchmarks and Monitoring Results
SAMPLE COLLECTION YEAR 2017
SAMPLE PERIOD M Jan -June ❑ July -Dec
or ❑ Monthly' (month)
DISCHARGING TO CLASS ❑ORW ❑HQW [—]Trout ❑PNA
❑Zero -flow ❑Water Supply ❑SA
®Other Bowes Branch Class C
PLEASE REMEMBER TO SIGN ON THE REVERSE 4
❑ No discharge this period?'
Outfall No.
Conductivity
Copper
Total
Fluoride
Total
Hardness
Total
Lead
Total
Mercury
Total
Molybdenum
Total
Nickel
Total
Units
S/m
mg/I
mg/I
mg/I
mg/I
mg/I
mg/I
mg/I
Benchmarks =__>
SDO 001
0.0098
<0.011
0.089
32.30
<0.009
<0.00007
0.016
<0.044
SDO 002
0.00702
<0.011
0.052
24.9
<0.009
<0.00007
<0.011
<0.044
SDO 003
0.0156 1
<0.011
0.055
44.70
<0.009
I <0.00007
<0.011
<0.044
1 Monthly sampling (instead of semi-annual) must begin with the second consecutive benchmark exceedance for the same parameter at the same outfall.
z For sampling periods with no discharge at any single outfall, you must still submit this discharge monitoring report with a checkmark here.
3The total precipitation must be recorded using data from an on -site rain gauge. Unattended sites may be eligible for a waiver of the rain gauge requirement.
4 See General Permit text, Table 3, identifying the especially sensitive receiving water classifications where the more protective benchmark applies.
Note: Results must be reported in numerical format. For example, do not report Below Detection Limit, BDL, <PQL, Non -detect, ND, or other similar non -
numerical format. When results are below the applicable limits, they must be reported in the format, "<XX me/L", where XX is the numerical value of the
detection limit, reporting limit, etc. in mg/L. Conversely, where fecal coliform results exceed the dilution upper limit, report the result as ">XX".
Note: If you report a sample value in excess of the benchmark, you must implement Tier 1, Tier 2, or Tier 3 responses. See General Permit text.
Permit Date: 11/1/2012-10/31/2017 SWU-248, last revised 10/25/2012
Page 3 of 5

Semi-annual Stormwater Discharge Monitoring Report
for North Carolina Division of Water Quality General Permit No. NCG120000
Date submitted 07/19/2017
CERTIFICATE OF COVERAGE NO. NCG120101
FACILITY NAME Mayo Steam Plant Monofill
COUNTY Person
PERSON COLLECTING SAMPLES Heath Slade, Ronald Easley
LABORATORY_ Pace_ Lab Cert. # 667, 633, 40 & 12
Comments on sample collection or analysis:
Part A: Stormwater Benchmarks and Monitoring Results
SAMPLE COLLECTION YEAR 2017
SAMPLE PERIOD ® Jan -June ❑ July -Dec
or ❑ Monthly' rmonth)
DISCHARGING TO CLASS ❑ORW ❑HQW ❑Trout ❑PNA
[]Zero -flow [-]Water Supply ❑SA
®Other Bowes Branch Class C
PLEASE REMEMBER TO SIGN ON THE REVERSE 4
❑ No discharge this period?2
Outfall No.
pH
Selenium
Silver
Total
Sulfate
Total
Thallium
Total
Zinc
Total
Units
S.U.
mg/I
mg/I
mg/I
mg/I
mg/1
Benchmarks ===>
SDO 001
7.13 @ 26.2
<0.031
<0.007
2.1
<0.0015
<0.24
SDO 002
7.29 @ 25.5
<0.031
<0.007
3.7
<0.0015
<0.24
SDO 003
7.76 @ 23.9
<0.031
<0.007
14.2
0.0022
<0.24
1 Monthly sampling (instead of semi-annual) must begin with the second consecutive benchmark exceedance for the same parameter at the same outfall.
Z For sampling periods with no discharge at any single outfall, you must still submit this discharge monitoring report with a checkmark here.
a The total precipitation must be recorded using data from an on -site rain gauge. Unattended sites may be eligible for a waiver of the rain gauge requirement.
4 See General Permit text, Table 3, identifying the especially sensitive receiving water classifications where the more protective benchmark applies.
Note: Results must be reported in numerical format. For example, do not report Below Detection Limit, BDL, <PQL, Non -detect, ND, or other similar non -
numerical format. When results are below the applicable limits, they must be reported in the format, "<XX me/L", where XX is the numerical value of the
detection limit, reporting limit, etc. in mg/L. Conversely, where fecal coliform results exceed the dilution upper limit, report the result as ">XX".
Note: if you report a sample value in excess of the benchmark, you must implement Tier 1, Tier 2, or Tier 3 responses. See General Permit text.
Permit Date: 11/1/2012-10/31/2017 5WU-248, last revised 10/25/2012
Page 4 of 5

Part B: Vehicle Maintenance Area Monitoring Results: only for facilities averaging > 55 gal of new oil per month.
❑ No discharge this period:2
Outfall No.
Date Sample
Collected'
(mo/dd/yr)
24-hour rainfall
amount,
Inches3
Non -polar O&G/TPH by
EPA 1664 (SGT-HEM)
Total Suspended Solids
pH
Benchmarks =__>
_
-
15 mg/L
100 mg/L or 50 mg/L
6.0 — 9.0 SU
Footnotes from Part A also apply to this Part B
Note: If you report a sample value in excess of the benchmark, you must implement Tier 1, Tier 2, or Tier 3 responses. See General Permit text.
FOR PART AND PART B MONITORING RESULTS:
• A BENCHMARK EXCEEDANCE TRIGGERS TIER 1 REQUIREMENTS. SEE PERMIT PART II SECTION B.
• 2 EXCEEDANCES IN A ROW FOR THE SAME PARAMETER AT THE SAME OUTFALL TRIGGER TIER 2 REQUIREMENTS. SEE PERMIT PART II SECTION B.
• TIER 3: HAS YOUR FACILITY HAD 4 OR MORE BENCHMARK EXCEEDENCES FOR THE SAME PARAMETER AT ANYONE OUTFALL? YES ❑ NO ❑
IF YES, HAVE YOU CONTACTED THE DWQ REGIONAL OFFICE? YES ❑ NO ❑
REGIONAL OFFICE CONTACT NAME:
Mail an original and one copy of this DMR, including al! "No Discharae" reports, within 30 dovs of receipt of the lab results for at end of monitorina period
in the case of "No Discharae" reports) to:
Division of Water Quality
Attn: DWQ Central Files
1617 Mail Service Center
Raleigh, North Carolina 27699-1617
YOU MUST SIGN THIS CERTIFICATION FOR ANY INFORMATION REPORTED:
"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."
(Signature of�Qere{iittee)
07111411-7
(Date)
Permit Date:11/1/2012-10/31/2017
SWU-248, last revised 10/25/2012
Page 5 of 5

\�
�ry
Semi-annual Stormwater Discharge Monitoring Report
for North Carolina Division of Water Quality General Permit No. NCG120000
Date submitted
CERTIFICATE OF COVERAGE NO. NCG120101
FACILITY NAME Mayo Steam Plant Monofill
COUNTY Person
PERSON COLLECTING SAMPLES Heath Slade
LABORATORY Pace Lab Cert. ## 667,633,40 & 12
Comments on sample collection or analysis:
Part A: Stormwater Benchmarks and Monitoring Results
01/03/2017
SAMPLE COLLECTION YEAR 2016
SAMPLE PERIOD ❑ Jan -June ® July -Dec
or ❑ Monthly' (month)
DISCHARGING TO CLASS ❑ORW ❑HQW ❑Trout ❑PNA
❑Zero -flow [:]WaterSupply ❑SA
X❑Other Bowes Branch Class C
PLEASE REMEMBER TO SIGN ON THE REVERSE 4
❑ No discharge this period?2
Outfall No.
Date Sample
Collected'
(mo/dd/yr)
24-hour rainfall
amount,
inches
Arsenic
Selenium
Boron
Benchmarks
-
-
mg/L
mg/L
mg/L
001
12/06/2016
0.71
0.0005
<0.00031
0.674
002
12/06/2016
0.71
0.0007
<0.00031
0.029
003
12/06/2016
0.71
0.0072
0.00046
0.186
1 Monthly sampling (instead of semi-annual) must begin with the second consecutive benchmark exceedance for the same parameter at the same outfall.
z For sampling periods with no discharge at any single outfall, you must still submit this discharge monitoring report with a checkmark here.
3The total precipitation must be recorded using data from an on -site rain gauge. Unattended sites may be eligible for a waiver of the rain gauge requirement.
4 See General Permit text, Table 3, identifying the especially sensitive receiving water classifications where the more protective benchmark applies.
Note: Results must be reported in numerical format. For example, do not report Below Detection Limit, SQL, <PQL, Non -detect, ND, or other similar non -
numerical format. When results are below the applicable limits, th_ey_must be reported in the format, "<XX m L", where XX is the numerical value of the
detection limit, reporting limit, etc. in mg/L. Conversely, where fecal coliform results exceed the dilution upper limit, report the result as ">XX".
Note: If you report a sample value in excess of the benchmark, you must implement Tier 1, Tier 2, or Tier 3 responses. See General Permit text.
Permit Date: 11/1/2012-10/31/2017 5WU-248, last revised 10/25/2012
Page 2 of 4

Semi-annual Stormwater Discharge Monitoring Report
for North Carolina Division of Water Quality General Permit No. NCG120000
Date submitted 01/03/2017
CERTIFICATE OF COVERAGE NO. NCG120101
FACILITY NAME Mayo Steam Plant Monofill_
COUNTY Person
PERSON COLLECTING SAMPLES Heath Slade
LABORATORY Pace Lab Cert. # 667,633.40 & 12
Comments on sample collection or analysis:
Part A: Stormwater Benchmarks and Monitoring Results
SAMPLE COLLECTION YEAR 2016
SAMPLE PERIODDan-June ® July -Dec
or ❑ Monthly' (month)
DISCHARGING TO CLASS ❑ORW ❑HQW ❑Trout ❑PNA
❑Zero -flow ❑Water Supply []SA
❑X Other Bowes Branch Class C
PLEASE REMEMBER TO SIGN ON THE REVERSE 4
❑ No discharge this period?2
Outfall No.
Date Sample
Collected
(mo/dd/yr)
24-hour rainfall
amount,
Inches3
Chemical Oxygen Demand
Fecal Coliform
Total Suspended Solids
Benchmarks =__>
-
-
120 mg/L
1000 count per 100 mL
100 mg/L
001
12/06/2016
0.71
13.0
89
7.7
002
12/06/2016
0.71
28.0
241
12.4
003
12/06/2016
0.71
43.0
437
44.8
1 Monthly sampling (instead of semi-annual) must begin with the second consecutive benchmark exceedance for the same parameter at the same outfall.
2 For sampling periods with no discharge at any single outfall, you must still submit this discharge monitoring report with a checkmark here.'
3The total precipitation must be recorded using data from an on -site rain gauge. Unattended sites may be eligible for a waiver of the rain gauge requirement.
4 See General Permit text, Table 3, identifying the especially sensitive receiving water classifications where the more protective benchmark applies.
Note: Results must be reported in numerical format. For example, do not report Below Detection Limit, BDL, <PQL, Non -detect, ND, or other similar non -
numerical format. When results are below the applicable limits, they must be reported in the format "<XX m L", where XX is the numerical value of the
detection limit, reporting limit, etc. in mg/L. Conversely, where fecal coliform results exceed the dilution upper limit, report the result as ">XX".
Note: If you report a sample value in excess of the benchmark, you must implement Tier 1, Tier 2, or Tier 3 responses. See General Permit text.
Permit Date: 11/1/2012-10/31/2017 SWU-248, last revised 10/25/2012
Page 1 of 4

Semi-annual Stormwater Discharge Monitoring Report
for North Carolina Division of Water Quality General Permit No. NCG120000
Date submitted Ol/03/2017
CERTIFICATE OF COVERAGE NO. NCG120101
FACILITY NAME Mayo Steam Plant Monofill
COUNTY Person
PERSON COLLECTING SAMPLES Heath Slade
LABORATORY Pace Lab Cert. # _667, 633, 40 & 12
Comments on sample collection or analysis:
Part A: Stormwater Benchmarks and Monitoring Results
SAMPLE COLLECTION YEAR 2016
SAMPLE PERIOD Dan -June ® July -Dec
or ❑ Monthly' month
DISCHARGING TO CLASS ❑ORW [—]HQW ❑Trout ❑PNA
❑Zero -flow ❑Water Supply [:]SA
X�Other Bowes Branch Class C
PLEASE REMEMBER TO SIGN ON THE REVERSE 4
No discharge this period?z
Outfall No.
Hate Sample
Collected
(mo/dd/yr)
24-hour rainfall
amount,
Inches
pH
Conductivity
Benchmarks
-
-
S.U.
S/m
001
12/06/2016
0.71
6.96
0.0444
002
12/06/2016
0.71
7.34
0.0070
003
12/06/2016
0.71
8.09
0.0168
1 Monthly sampling (instead of semi-annual) must begin with the second consecutive benchmark exceedance for the same parameter at the same outfall.
2 For sampling periods with no discharge at any single outfall, you must still submit this discharge monitoring report with a checkmark here.
3The total precipitation must be recorded using data from an on -site rain gauge. Unattended sites may be eligible for a waiver of the rain gauge requirement.
4 See General Permit text, Table 3, identifying the especially sensitive receiving water classifications where the more protective benchmark applies.
Note: Results must be reported in numerical format. For example, do not report Below Detection Limit, BDL, <PQL, Non -detect, ND, or other similar non -
numerical format. When results are below the applicable limits, they must be reported in the format, "<XX mg/L", where XX is the numerical value of the
detection limit, reporting limit, etc. in mg/L. Conversely, where fecal coliform results exceed the dilution upper limit, report the result as ">XX".
Note: if you report a sample value in excess of the benchmark, you must implement Tier 1, Tier 2, or Tier 3 responses. See General Permit text.
Permit Date: 11/1/2012-10/31/2017 SWU-248, last revised 10/25/2012
Page 3 of 4

Part B: Vehicle Maintenance Area Monitoring Results: only for facilities averaging > 55 gal of new oil per month.
❑ No discharge this period?z
Outfall No.
Date Sample
Collected'
(mo/dd/yr)
24-hour rainfall
amount,
Inches3
Non -polar O&G/TPH by
EPA 1664 (SGT-HEM)
Total Suspended Solids
pH
Benchmarks =__>
_
-
15 mg/L
100 mg/L or 50 mg/L
6.0 — 9.0 SU
Footnotes from Part A also apply to this Part B
Note: if you report a sample value in excess of the benchmark, you must implement Tier 1, Tier 2, or Tier 3 responses. See General Permit text.
FOR PART A AND PART B MONITORING RESULTS:
• A BENCHMARK EXCEEDANCE TRIGGERS TIER 1 REQUIREMENTS. SEE PERMIT PART II SECTION B.
• 2 EXCEEDANCES IN A ROW FOR THE SAME PARAMETER AT THE SAME OUTFALL TRIGGER TIER 2 REQUIREMENTS. SEE PERMIT PART II SECTION B.
• TIER 3: HAS YOUR FACILITY HAD 4 OR MORE BENCHMARK EXCEEDENCES FOR THE SAME PARAMETER AT ANY ONE OUTFALL? YES ❑ NO©
IF YES, HAVE YOU CONTACTED THE DWQ REGIONAL OFFICE? YES ❑ NO ❑
REGIONAL OFFICE CONTACT NAME:
Mail an oriainal and one coov of this DMR. includina all "No Discharae" reports. within 30 days of receipt of the lob results (or at end of monitoring period
in the case d"No Discharge" reports) to:
Division of Water Quality
Attn: DWQ Central Files
1617 Mail Service Center
Raleigh, North Carolina 27699-1617
YOU MUST SIGN THIS CERTIFICATION FOR ANY INFORMATION REPORTED:
"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."
01 jd+"/ II?
(Signature of Permi ee) (Date)
Permit Date: 11/l/2012-10/31/2017 SWU-248, last revised 10/25/2012
Page 4 of 4

DUKE
ENERGY®
PROGRESS
File: Mayo 12520-R
Mayo Steam Plan%
Duke Energy Progress
10660 Boston Road
Roxboro, NC 27574
NC Division of Water Resources 01/03/2017
ATTENTION: Central Files
1617 Mail Service Center
Raleigh, North Carolina 27699-1617
Subject: 15A N. C. Admin. Code 213 .0506
N,Iavo Electric Generating Plant
National Pollutant Discharge Elimination System (NPDES) Number NCG120101
Monofill Stormwater Discharge Outfall Monitoring Report
Dear Sir or Madam:
Please find enclosed the 2016 July -Dec. semi-annual Monofill Stormwater Discharge Monitoring Report
for Permit Number NCG l 20101, SDO 001, SDO 002 & SDO 003, for Duke Energy Progress, LLC. The
Mayo Electric Generating Plant Monofill became operational November 7, 2014.
I certify, under- penalty of law, that this document and all attachments were prepared under nrr direction or
supervision in accordance with a system designed to assure that qualified personnel proper!• lather and evaluate
the information submitted. Based orr my inquiry' cif the person or persons who manage the system, or those parsons
directly responsible forgathering the information, the information submitted is, to the hest of'mr knowledge and
belief true, accurate, and complete. 1 corn aware that there are significant penalties for suhcititting false information.
inchcding the po.ssihilitti• of fines and imprisornnnent for knowing i-iolations.
Please contact Mr. Shannon Langley at [phone], if there are any questions concerning the data in
this submittal.
Sincerely,
Enclosures
Tom Copolo - Manager
Mayo Electric Generating Plant

DUKE
ENERGY,
PROGRESS
File: Mayo 12520-R
Mayo Steam Plant
Duke Energy Progress
10660 Boston Road
Roxboro, NC 27574
NC Division of Water Resources C61 V FO6 44/2016
ATTENTION: Central Files JUN 2 g
1617 Mail Service Center
Raleigh, North Carolina 27699-1617�� FILES
R
Subject: 15A N. C. Admin. Code 213.0506
Mayo Electric Generating Plant
National Pollutant Discharge Elimination System (NPDES) Number NCG 120101
Monofill Stormwater Discharge Outfall Monitoring Report
Dear Sir or Madam:
Please find enclosed the 2016 Jan. -June semi-annual Monofill Stormwater Discharge Monitoring Report
for Permit Number NCG120101, SDO 001, SDO 002 & SDO 003, for Duke Energy Progress, LLC. The
Mayo Electric Generating Plant Monofill became operational November 7, 2014,
I certify, trader penalty of law, that this document and all atrachments 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 ttry knowledge and
belief, true, accurate, and complete. 1 can aware that there are significant penalties for subanitting false information,
including fire possibility of fines and imprisavunent for knowing violations.
Please contact Mr. Shannon Langley at [phone], if there are any questions concerning the data in
this submittal.
Sincerely,
Enclosures
Tom Copolo - Manager
Mayo Electric Generating Plant

Semi-annual Stormwater Discharge Monitoring Report
for North Carolina Division of Water Quality General Permit No. NCG120000
Date submitted
CERTIFICATE OF COVERAGE NO. NCG120101
FACILITY NAME Mayo Steam Plant Monofill
COUNTY Person
PERSON COLLECTING SAMPLES Heath Slade
LABORATORY Pace Lab Cert. # 667,633.40 & 12
Comments on sample collection or analysis:
Part A: Stormwater Benchmarks and Monitoring Results
06/14/2016
SAMPLE COLLECTION YEAR 2016
SAMPLE PERIOD ❑X Jan -June ❑ July -Dec
or ❑ Monthly' month
DISCHARGING TO CLASS ❑ORW ❑HQW ❑Trout ❑PNA
❑Zero -flow []Water Supply ❑SA
RCF_w ❑X Other Bowes Branch Class C
jo S $ J16 PLEASE REMEMBER TO SIGN ON THE REVERSE 4
nwR sECT%ON
❑ No discharge this period?'
outfall No.
Date Sample
Collected'
(mo/dd/yr)
24-hour rainfall
amount,
Inches3
Chemical Oxygen Demand
Fecal Coliform
Total Suspended Solids
Benchmarks =__>
-
-
120 mg/L
1000 count per 100 mL
100 mg/L
001
05/17/2016
0.90
27.0
2420
15.5
002
05/17/2016
0.90
32.0
2420
13.0
003
05/17/2016
0.90
19.0
2420
44.1
' Monthly sampling (instead of semi-annual) must begin with the second consecutive benchmark exceedance for the same parameter at the same outfall.
z For sampling periods with no discharge at any single outfall, you must still submit this discharge monitoring report with a checkmark here.
3The total precipitation must be recorded using data from an on -site rain gauge. Unattended sites may be eligible for a waiver of the rain gauge requirement.
4 See General Permit text, Table 3, identifying the especially sensitive receiving water classifications where the more protective benchmark applies.
Note: Results must be reported in numerical format. For example, do not report Below Detection Limit, BDL, <PQL, Non -detect, ND, or other similar non -
numerical format. When results are below the applicable limits, they must be reported in the format. "<XX mg/L", where XX is the numerical value of the
detection limit, reporting limit, etc. in mg/L_ Conversely, where fecal coliform results exceed the dilution upper limit, report the result as ">XX".
Note: If you report a sample value in excess of the benchmark, you must implement Tier 1, tier 2, or Tier 3 responses. See General Permit text.
Permit Date: 11/l/2012-10/31/2017 SWU-248, last revised 10/25/2012
Page 1 of 4

Semi-annual Stormwater Discharge Monitoring Report
for North Carolina Division of Water Quality General Permit No. NCG120000
Date submitted 06/14/2016
CERTIFICATE OF COVERAGE NO. NCG120101
FACILITY NAME Mayo Steam Plant Monofill
COUNTY Person
PERSON COLLECTING SAMPLES Heath Slade
LABORATORY Pace Lab Cert. ## 667,633.40 & 12
Comments on sample collection or analysis:
Part A: Stormwater Benchmarks and Monitoring Results
SAMPLE COLLECTION YEAR 2016
SAMPLE PERIOD ® Jan -June ❑ July -Dec
or ❑ Monthly' (month)
DISCHARGING TO CLASS ❑ORW ❑HQW [—]Trout ❑PNA
[]Zero -flow ❑Water Supply []SA
X❑Other Bowes Branch Class C
PLEASE REMEMBER TO SIGN ON THE REVERSE 4
❑ No discharge this period?z
Outfall No.
Date Sample
Collected'
(mo/dd/yr)
24-hour rainfall
amount,
Inches
Arsenic
Selenium
Boron
Benchmarks =__>
-
-
mg/L
mg/L
mg/L
001
05/17/2016
0.90
0.0025
0.00094
0.396
002
05/17/2016
0.90
0.00066
<0.00031
0.0304
003
05/17/2016
0.90
0.0042
0.00056
0.071
1 Monthly sampling (instead of semi-annual) must begin with the second consecutive benchmark exceedance for the same parameter at the same outfall.
Z For sampling periods with no discharge at any single outfall, you must still submit this discharge monitoring report with a checkmark here.
3The total precipitation must be recorded using data from an on -site rain gauge. Unattended sites may be eligible for a waiver of the rain gauge requirement.
4 See General Permit text, Table 3, identifying the especially sensitive receiving water classifications where the more protective benchmark applies.
Note: Results must be reported in numerical format. For example, do not report Below Detection Limit, BDL, <PQL, Non -detect, ND, or other similar non -
numerical format. When results are below the applicable limits, they must be reported in the format, "<XX me/L", where XX is the numerical value of the
detection limit, reporting limit, etc. in mg/L. Conversely, where fecal coliform results exceed the dilution upper limit, report the result as ">XX".
Note: if you report a sample value in excess of the benchmark, you must implement Tier 1, Tier 2, or Tier 3 responses. See General Permit text.
Permit Date: 11/1/2012-10/31/2017 5WU-248, last revised 10/25/2012
Page 2 of 4

Semi-annual Stormwater Discharge Monitoring Report
for North Carolina Division of Water Qu lity General Permit No. NCG120000
Date submitted
CERTIFICATE OF COVERAGE NO. NCG120101
FACILITY NAME Mayo Steam Plant Monofill
COUNTY Person
PERSON COLLECTING SAMPLES Ronald Easley
LABORATORY Pace Lab Cert. ## 667,633,40 & 12_
Comments on sample collection or analysis:
* 42 hour rainfall event = 1.30"
Part A: Stormwater Benchmarks and Monitoring Results
SAMPLE COLLECTION YEAR ' 2015
SAMPLE PERIOD ❑ Jan -June ❑x July -Dec
or ❑ Monthly'(month
DISCHARGING TO CLASS ❑ORW ❑HQW ❑Trout `[!PNA
❑Zero -flow []Water Supply ❑SA
© Other Bowes Branch Class C
PLEASE REMEMBER TO SIGN -�
No discharge this period?z
Outfall No.
Date Sample
Collected
(mo/dd/yr)
24-hour rainfall
amount,
Inches
Chemical oxygen Demand
Fecal Coliform
Total Suspended Solids
Benchmarks =__>
-
-
120 mg/L
1000 count per 100 mL
100 mg/L or 50 mg/L
001
10/28/2015
* 1,30"
<12.5
54.7
4.9
002
10/28/2015
* 1.30"
19.0
69.8
12.1
003
10/28/2015
* 1.30"
15.0
38.2
7.0
' Monthly sampling (instead of semi-annual) must begin with the second consecutive benchmark exceedance for the same parameter at the same outfall.
z For sampling periods with no discharge at any single outfall, you must still submit this discharge monitoring report with a checkmark here.
3The total precipitation must be recorded using data from an on -site rain gauge. Unattended sites may be eligible for a waiver of the rain gauge requirement.
4 See General Permit text, Table 3, identifying the especially sensitive receiving water classifications where the more protective benchmark applies.
Note: Results must be reported in numerical format. For example do not report Below Detection Limit, BDL, <PQL, Non -detect, ND, or other similar non -
numerical format. When results are below the applicable limits, they must be reported in the format, "<XX me/L", where XX is the numerical value of the
detection limit, reporting limit, etc. in mg/L. Conversely, where fecal coliform results exceed the dilution upper limit, report the result as ">XX".
Note: if you report a sample value in excess of the benchmark, you must implement Tier 1, Tier 2, or Tier 3 responses. See General Permit text.
Permit Date: 11/1/2012-10/31/2017 SWU-248, last revised 10/25/2012
Page 1 of 5

Semi-annual Stormwater Discharge Monitoring Report
for North Carolina Division of Water Quality General Permit No. NCG120000
Date submitted //12-o
CERTIFICATE OF COVERAGE NO. NCG120101
FACILITY NAME Mayo Steam Plant Monofill
COUNTY Person
PERSON COLLECTING SAMPLES Ronald Easley
LABORATORY Pace Lab Cert. # 667,633,40 & 12
Comments on sample collection or analysis:
* 42 hour rainfall event = 1.30"
Part A: Stormwater Benchmarks and Monitoring Results
SAMPLE COLLECTION YEAR 2015
SAMPLE PERIOD ❑ Jan -June ❑x luly-Dec
or ❑ monthly' (month)
DISCHARGING TO CLASS ❑ORW ❑HQW ❑Trout ❑PNA
[]Zero -flow ❑Water Supply ❑SA
❑x Other Bowes Branch Class C
PLEASE REMEMBER TO SIGN 4
No discharge this period:2
Outfall No.
Hate Sample
Collected'
(mo/dd/yr)
24-hour rainfall
amount,
inches
Arsenic
Selenium
Boron
Benchmarks =__>
_
-
mg/L
mg/L
mg/L
001
10/28/2015
* 1.30"
0.00083
0.00028
<0.0250
002
10/28/2015
* 1.30"
0.00041
0.00017
0.0255
003
10/28/2015
* 1.30"
0.00380
0.00044
0.1120
Monthly sampling (instead of semi-annual) must begin with the second consecutive benchmark exceedance for the same parameter at the same outfall.
z For sampling periods with no discharge at any single outfall, you must still submit this discharge monitoring report with a checkmark here.
3The total precipitation must be recorded using data from an on -site rain gauge. Unattended sites may be eligible for a waiver of the rain gauge requirement.
" See General Permit text, Table 3, identifying the especially sensitive receiving water classifications where the more protective benchmark applies.
Note: Results must be reported in numerical format. For example, do not report Below Detection Limit, BDL, <PQL, Non -detect, ND, or other similar non -
numerical format. When results are below the applicable limits, they must be reported in the format "<XX m L", where XX is the numerical value of the
detection limit, reporting limit, etc. in mg/L. Conversely, where fecal coliform results exceed the dilution upper limit, report the result as ">XX".
Note: If you report a sample value in excess of the benchmark, you must implement Tier 1, Tier 2, or Tier 3 responses. See General Permit text.
Permit Date: 11/1/2012-10/31/2017 5WU-248, last revised 10/25/2012
Page 2 of 5

Semi-annual Stormwater Discharge Monitoring Report
for North Carolina Division of Water Quality General Permit No. NCG120000
Date submitted
CERTIFICATE OF COVERAGE NO. NCG120101 SAMPLE COLLECTION YEAR 2015
FACILITY NAME Mayo Steam Plant Monofill SAMPLE PERIOD ❑ Jan -June ❑x luly-Dec
COUNTY Person or ❑ Monthly) (month)
PERSON COLLECTING SAMPLES Ronald Easley DISCHARGING TO CLASS ❑ORW ❑HOW ❑Trout ❑PNA
LABORATORY Pace Lab Cert. # 667,633,40 & 12 ❑Zero -flaw [_]WaterSupply ❑SA
Comments on sample collection or analysis: ❑x Other Bowes Branch Class C
* 24 hour rainfall event = 1.30"
Part A: Stormwater Benchmarks and Monitoring Results
PLEASE REMEMBER TO SIGN 4
❑ No discharge this period?'
Outfall No.
Date Sample
Collected'
(mo/dd/yr)
24-hour rainfall
amount,
Inches3
P H
Conductivity
(Mayo Plant Lab)
Conductivity
(Pace Lab)
Benchmarks =__>
-
-
S.U.
S/m
S/m
001
10/28/2015
* 1.30"
8.12
0.007384
0.00836
002
10/28/201S
* 1.30"
6.93
0.007811
0.00838
003
10/28/2015
* 1.30"
7.95
0.020710
0.02400
1 Monthly sampling (instead of semi-annual) must begin with the second consecutive benchmark exceedance for the same parameter at the same outfall.
z For sampling periods with no discharge at any single outfall, you must still submit this discharge monitoring report with a checkmark here.
3The total precipitation must be recorded using data from an on -site rain gauge. Unattended sites may be eligible for a waiver of the rain gauge requirement.
4 See General Permit text, Table 3, identifying the especially sensitive receiving water classifications where the more protective benchmark applies.
Note: Results must be reported in numerical format. For example, do not report Below Detection Limit, BDL, <PQL, Non -detect, ND, or other similar non -
numerical format. When results are below the applicable limits, they must be reported in the format, "<XX mg/L", where XX is the numerical value of the
detection limit, reporting limit, etc. in mg/L. Conversely, where fecal coliform results exceed the dilution upper limit, report the result as ">XX".
Note: If you report a sample value in excess of the benchmark, you must implement Tier 1, Tier 2, or Tier 3 responses. See General Permit text.
Permit Date: 11/1/2012-10/31/2017 SWU-248, last revised 10/25/2012
Page 3 of 5

Part B: Vehicle Maintenance Area Monitoring Results: only for facilities averaging > 55 gal of new oil per month.
❑ No discharge this period?'
Outfall No.
Date Sample
Collected'
(mo/dd/yr)
24-hour rainfall
amount,
Inches3
Non -polar O&G/TPH by
EPA 1664 (SGT-HEM)
Total Suspended Solids
pH
Benchmarks =__>
_
-
15 mg/L
100 mg/L or 50 mg/L
6.0 — 9.0 SU
Footnotes from Part A also apply to this Part B
Note: If you report a sample value in excess of the benchmark, you must implement Tier 1, Tier 2, or Tier 3 responses. See General Permit text.
FOR PART A AND PART B MONITORING RESULTS:
• A BENCHMARK EXCEEDANCE TRIGGERS TIER 1 REQUIREMENTS. SEE PERMIT PART II SECTION B.
• 2 EXCEEDANCES 1N A ROW FOR THE SAME PARAMETER AT THE SAME OUTFALL TRIGGER TIER 2 REQUIREMENTS. SEE PERMIT PART II SECTION B.
• TIER 3: HAS YOUR FACILITY HAD 4 OR MORE BENCHMARK EXCEEDENCES FOR THE SAME PARAMETER AT ANY ONE OUTFALL? YES ❑ NO®
IF YES, HAVE YOU CONTACTED THE DWQ REGIONAL OFFICE? YES ❑ NO
REGIONAL OFFICE CONTACT NAME:
Mail an orirfinal and one copy of -this DMR, including all "No Discharge" reports, within 30 days of receipt of the lab results for at end of monitoring aeriod
in the case of "No Discharge" reports) to:
Division of Water Quality
Attw DWQ Central Files
1617 Mail Service Center
Raleigh, North Carolina 27699-1617
YOU MUST SIGN THIS CERTIFICATIQN FOR ANY INFORMATION_ REPORTED:
"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,
am aware that there are significant penalties for submitting false information, including the possibility of fines and imprisonment for knowing violations."
(Signature of Perni
11 1141 Ig
(Date)
Permit Date: 11/1/2012-10/31/2017 SWU-248, last revised 10/25/2012
Page 5 of 5

NOV , 2 0 2015,,:
DUKE
ENERGY®
PROGRESS
File: Mayo 12520-R
RECEIVED
NA 2 4 2015
Mayo Steam Plant
Duke Energy Progress
10660 Boston Road
Roxboro, NC 27574
NC Division of Water Resources
ATTENTION: Central Files CENTRAL FILES
1617 Mail Service Center DWR SECTION
Raleigh, North Carolina 27699-1617
Subject: 15A N. C. Admin. Code 213.0506
Mayo Electric Generating Plant
National Pollutant Discharge Elimination System (NPDES) Number NCG 120101
Monofill Stormwater Discharge Outfall Monitoring Report
Dear Sir or Madam:
Please find enclosed the 2015 July -Dec. semi-annual Monofill Stormwater Discharge Monitoring Report
for Permit Number NCG120101, SDO 001, SDO 002 & SDO 003, for Duke Energy Progress, LLC. The
Mayo Electric Generating Plant Monofill became operational November 7, 2014.
1 certih,, under penalty of last', that this docrnnew and all attachments were prepared under my direction or
supen4sion in accordance with a system designed to assure that qualified personnel properly gather and evoluate
the information submitted. Based on my inquin� of the person or persons who manage the system, or those persons
directly responsible far gathering the information, the it formation submitted is, to the best of my knowledge cold
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.
Please contact Mr. Shannon Langley at [phone], if there are any questions concerning the data in
this submittal.
Sincerely,
Enclosures
Tom Copolo - Manager
Mayo Electric Generating Plant

Semi-annual Stormwater Discharge Monitoring Report
for North Carolina Division of Water Qua ity General Permit No. NCG120000
Date submitted O S
CERTIFICATE OF COVERAGE No. NCG120101
FACILITY NAME Mayo Steam Plant Monofill
COUNTY Person
PERSON COLLECTING SAMPLES Ronald Easley
LABORATORY Pace Lab Cert. # 667,633.40 & 12
Comments on sample collection or analysis:
Part A: Stormwater Benchmarks and Monitoring Results
SAMPLE COLLECTION YEAR 2015
SAMPLE PERIOD K❑ an -June ❑ July -Dec
or ❑ Monthly( (month)
DISCHARGING TO CLASS ❑ORW ❑HQW []Trout ❑PNA
RECEIVED
❑Zero-flow []Water Supply []SA
❑X Other Bowes Branch Class C
JUL f 1 4iiD
CENTRAL FIJ
DWR SECT1L0-
PLEASE REMEMBER TO SIGN ON THE REVERSE 4
No discharge this period?2
Outfall No.
Date Sample
Collected'
(mo/dd/yr)
24-hour rainfall
amount,
Inches3
Chemical Oxygen Demand
Fecal Colifarm
Total Suspended Solids
Benchmarks =__>
-
-
120 mg/L
1000 count per 100 mL
100 mg/L
001
06/03/2015
3.3
23.0
3.1
75.4
002
06/03/2015
3.3
23.0
3.1
37.6
003
06/03/2015
3.3
30.0
152
62.5
1 Monthly sampling (instead of semi-annual) must begin with the second consecutive benchmark exceedance for the same parameter at the same outfall.
z For sampling periods with no discharge at any single outfall, you must still submit this discharge monitoring report with a checkmark here.
3The total precipitation must be recorded using data from an on -site rain gauge. Unattended sites may be eligible for a waiver of the rain gauge requirement.
° See General Permit text, Table 3, identifying the especially sensitive receiving water classifications where the more protective benchmark applies.
Note: Results must be reported in numerical format. For example, do not report Below Detection Limit, BDL, <PQL, Non -detect, ND, or other similar non -
numerical format. When results are below the applicable limits, they must be reported in the format, "<XX mg/L", where XX is the numerical value of the
detection limit, reporting limit, etc. in mg/L. Conversely, where fecal coliform results exceed the dilution upper limit, report the result as ">XX".
Note: If you report a sample value in excess of the benchmark, you must implement Tier I, Tier 2, or Tier 3 responses. See General Permit text.
Permit Date: 11/1/2012-10/31/2017 SWU-248, last revised 10/25/2012
Page 1 of 5

Semi-annual Stormwater Discharge Monitoring Report
for North Carolina Division of Water Quality General Permit No. NCG120000
Date submitted 2—Ci'S
CERTIFICATE OF COVERAGE NO. NCG120101
FACILITY NAME Mayo Steam Plant Monofill
COUNTY Person
PERSON COLLECTING SAMPLES Ronald Easley
LABORATORY Pace Lab Cert. # 667,633,40 & 12
Comments on sample collection or analysis: -
Part A: Stormwater Benchmarks and Monitoring Results
SAMPLE COLLECTION YEAR 2015
SAMPLE PERIOD ® Jan -June ❑ July -Dec
or [:]Monthly' (month)
DISCHARGING TO CLASS ❑ORW ❑HQW ❑Trout ❑PNA
❑Zero -flaw [—]Water Supply ❑SA
❑X Other Bowes Branch Class C
PLEASE REMEMBER TO SIGN ON THE REVERSE 4
❑ No discharge this period?z
Outfall No.
date Sample
Collected'
(mo/dd/yr)
24-hour rainfall
amount,
Inches
Arsenic
Selenium
Boron
Benchmarks =__>
-
-
mg/L
mg/L
mg/L
001
06/03/2015
3.3
0.0016
0.00044
0.0364
002
06/03/2015
3.3
0.0029
0.00038
0.084
003
06/03/2015
3.3
0.0009
0.00029
0.0335
' Monthly sampling (instead of semi-annual) must begin with the second consecutive benchmark exceedance for the same parameter at the same outfall.
2 For sampling periods with no discharge at any single outfall, you must still submit this discharge monitoring report with a checkmark here.
3The total precipitation must be recorded using data from an on -site rain gauge. Unattended sites may be eligible for a waiver of the rain gauge requirement.
`See General Permit text, Table 3, identifying the especially sensitive receiving water classifications where the more protective benchmark applies.
Note: Results must be reported in numerical format. For example, do not report Below Detection Limit, BDL, <PQL, Non -detect, ND, or other similar non -
numerical format. When results are below the applicable limits, they must be reported in the format, "<XX mg/L", where XX is the numerical value of the
detection limit, reporting limit, etc. in mg/L. Conversely, where fecal coliform results exceed the dilution upper limit, report the result as ">XX".
Note: If you report a sample value in excess of the benchmark, you must implement Tier 1, Tier 2, or Tier 3 responses. See General Permit text.
Permit Date: 11/1/2012-10/31/2017 SWU-248, last revised 10/25/2012
Page 2 of 5

Semi-annual Stormwater Discharge Monitoring Report
for North Carolina Division of Water Quality General Permit No. NCG120000
Date submitted Z© L_�E:
CERTIFICATE OF COVERAGE NO. NCG120101
FACILITY NAME Mayo Stearn Plant Monofiil
COUNTY Person
PERSON COLLECTING SAMPLES Ronald Easley
LABORATORY Pace Lab Cert. # _667, 633, 40 & 12
Comments on sample collection or analysis:
Part A: Stormwater Benchmarks and Monitoring Results
SAMPLE COLLECTION YEAR 2015
SAMPLE PERIOD K�lan-June ❑ July -Dec
or ❑ Monthly' (month)
DISCHARGING TO CLASS ❑ORW ❑HQW []Trout ❑PNA
❑Zero -flow Water Supply ❑SA
Other Bowes Branch Class C
PLEASE REMEMBER TO SIGN ON THE REVERSE 4
❑ No discharge this period?z
Outfall No.
date Sample
Collected'
(mo/dd/yr)
24-hour rainfall
amount,
Inches
pH
Conductivity
Manganese
Benchmarks
-
-
S.U.
S/m
mg/L
001
06/03/2015
3.3
7.33
0.01031
0.077
002
06/03/2015
3.3
6.97
0,006148
0.0617
003
06/03/2015
3.3
7.94
0.009131
0.0348
1 Monthly sampling (instead of semi-annual) must begin with the second consecutive benchmark exceedance for the same parameter at the same outfall.
2 For sampling periods with no discharge at any single outfall, you must still submit this discharge monitoring report with a checkmark here.
3The total precipitation must be recorded using data from an on -site rain gauge. Unattended sites may be eligible for a waiver of the rain gauge requirement.
4 See General Permit text, Table 3, identifying the especially sensitive receiving water classifications where the more protective benchmark applies.
Note: Results must be reported in numerical format. For example, do not report Below Detection Limit, BDL, <PQL, Non -detect, ND, or other similar non -
numerical format. When results are below the applicable limits, they must be reported in the format, "<XX mg/L", where XX is the numerical value of the
detection limit, reporting limit, etc. in mg/L. Conversely, where fecal coliform results exceed the dilution upper limit, report the result as ">XX".
Note: if you report a sample value in excess of the benchmark, you must implement Tier 1, Tier 2, or Tier 3 responses. See General Permit text.
Permit Date: 11/1/2012-10/31/2017 SWU-248, last revised 10/25/2012
Page 3 of 5

Semi-annual Stormwater Discharge Monitoring Report
for North Carolina Division of Water Quality/ General Permit No. NCG120000
Date submitted q r z®�J
CERTIFICATE OF COVERAGE NO. NCG120101
FACILITY NAME Mayo Steam Plant Monofill
COUNTY Person
PERSON COLLECTING SAMPLES _ Ronald Easley
LABORATORY Pace Lab Cert. # 667. 633, 40 & 12
Comments on sample collection or analysis:
Part A: Stormwater Benchmarks and Monitoring Results
SAMPLE COLLECTION YEAR 2015
SAMPLE PERIOD K❑Jan-June ❑ July -Dec
or ❑ Monthly' (month)
DISCHARGING TO CLASS ❑ORW ❑HQW ❑Trout ❑PNA
❑Zero -flow ❑Water Supply []SA
© Other Bowes Branch Class C
PLEASE REMEMBER TO SIGN ON THE REVERSE 4
❑ No discharge this period?z
Outfall No.
Date Sample
Collected'
(mo/dd/yr)
24-hour rainfall
amount,
Inches
Thallium
Benchmarks ===>
-
-
mg/L
001
06/03/2015
3.3
<0.00005
002
06/03/2015
3.3
<0.00005
003
06/03/2015
3.3
<0.00005
' Monthly sampling (instead of semi-annual) must begin with the second consecutive benchmark exceedance for the same parameter at the same outfall.
2For sampling periods with no discharge at any single outfall, you must still submit this discharge monitoring report with a checkmark here.
3The total precipitation must be recorded using data from an on -site rain gauge. Unattended sites may be eligible for a waiver of the rain gauge requirement.
See General Permit text, Table 3, identifying the especially sensitive receiving water classifications where the more protective benchmark applies.
Note: Results must be reported in numerical format. For example, do not report Below Detection Limit, BDL, <PQL, Non -detect, ND, or other similar non -
numerical format. When results are below the applicable limits, they must be reported in the format, <XX„me/L", where XX is the numerical value of the
detection limit, reporting limit, etc. in mg/L. Conversely, where fecal coliform results exceed the dilution upper limit, report the result as ">XX".
Nate: If you report a sample value in excess of the benchmark, you must implement Tier 1, Tier 2, or Tier 3 responses. See General Permit text.
Permit Date: 11/1/2012-10/31/2017 SWU-248, last revised 10/25/2012
Page 4 of 5

Part.B: Vehicle Maintenance Area Monitoring Results: only for facilities averaging > 55 gal of new oil per month.
❑ No discharge this period?2
Outfall No.
Date Sample
Collected'
(mo/dd/yr)
24-hour rainfall
amount,
Inches
Non -polar O&G/TPH by
EPA 1664 (SGT-HEM)
Total Suspended Solids
pH
Benchmarks =__>
_
-
15 mg/L
100 mg/L or 50 mg/L
6.0 — 9.0 SU
Footnotes from Part A also apply to this Part B
Note: If you report a sample value in excess of the benchmark, you must implement Tier 1, Tier 2, or Tier 3 responses. See General Permit text.
FOR PART A AND PART B MONITORING RESULTS:
• A BENCHMARK EXCEEDANCE TRIGGERS TIER 1 REQUIREMENTS. SEE PERMIT PART II SECTION B.
* 2 EXCEEDANCES IN A ROW FOR THE SAME PARAMETER AT THE SAME OUTFALL TRIGGER TIER 2 REQUIREMENTS. SEE PERMIT PART II SECTION B.
• TIER 3: HAS YOUR FACILITY HAD 4 OR MORE BENCHMARK EXCEEDENCES FOR THE SAME PARAMETER AT ANY ONE OUTFALL? YES ❑ NO®
IF YES, HAVE YOU CONTACTED THE DWQ REGIONAL OFFICE? YES ❑ NO ❑
REGIONAL OFFICE CONTACT NAME:
Mail an oriainal and one copv of this DMA, includina all "No Discharae" reports, within 30 days of receipt of the lab results (or at end of monitorina period
in the case of "No Discharae" reports) to:
Division of Water Quality
Attn: DWQ Central Files
1617 Mail Service Center
Raleigh, North Carolina 27699-1617
YOU MUST SIGN THIS CERTIFICATION FOR ANY INFORMATION REPORTED:
"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.
am aware that there are significant penalties for submitting false information, including the possibility of fines and imprisonment for knowing violations."
� 4
(Signature of Permittee)
(Date)
Permit Date: 11/1/2012-10/31/2017 SWU-245, last revised 10/25/2012
Page 5 of S

DUKE
ENERGY,
PROGRESS
File: Mayo 12520-R
NC Division of Water Resources
ATTENTION: Central Files
1617 Mail Service Center
Raleigh, North Carolina 27699-1617
JUL 0 9 2015 Mayo Steam Plant
Duke Energy Progress
10660 Boston Road
Roxboro, NC 27574
Subject: 15A N. C. Admin. Code 2B .0506
Mayo Electric Generating Plant
National Pollutant Discharge Elimination System (NPDES) Number NCG 120101
Monofill Stormwater Discharge Outfall Monitoring Report
Dear Sir or Madam:
Please find enclosed the 2015 Jan -June semi-annual Monofill Stormwater Discharge Monitoring Report
for Permit Number NCG120101, SDO 001, SDO 002 & SDO 003, for Duke Energy Progress, Inc. The
Mayo Electric Generating Plant Monofill became operational November 7, 2014.
I certify. under penalty of law, that this document and all attachments were prepared under mti� direction or
supervision in accordance with a system designed to assure that qualified personnel properly gather and evahrate
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 hest of my knowledge and
belief, true, accurate, and complete. 1 am aware that there are significant penalties for submitting false nrforrnation,
including the possibility of fines and irnprisonntent for knowing violations.
Please contact Mr. Shannon Langley at [phone], if there are any questions concerning the data in
this submittal.
Enclosures RECEIVED
JUL 13 Z015
CENTRAL FILES
DWR SECTION
Sincerely,
eyk (5, gj"vc
5�1_ -) 0&'1
William J. Thacker- Manager
Mayo Electric Generating Plant
R"ECEIVED
JUL z .-�
CE��N�TjRAL,�+FILERS

Lea, Herbert
From: Thacker, Jody
Sent: Thursday, July 02, 2015 7:34 AM
To: Draovitch, Paul; Strickland, Suzy; Honeycutt, Donald; Lea, Herbert; Long, Beverly;
Montgomery, Amanda; Talbott, Jason; Wilborn, Christopher; Draovitch, Paul; Neal, Brian;
Miller, Robert M
Subject: Thacker Out Of Office
Sensitivity: Private
All,
I will be out of office starting 7/3 and returning 7/13.
In my absence Chris Wilborn will be on point for the station and will have my signature authority for matters
that may arise. Chris can be reached via cell at 434-579-2578.
I will be available by phone or email should you need to reach me.
Jody
1

Mayo Steam Plant
ENERGY® Duke Energy Progress
PROGRESS rr 10660 Boston Road
U �� Roxboro, NC 27574
File: Mayo 12520-R
NC Division of Water Resources RECEIVED
IVED
ATTENTION: Central Files
1617 Mail Service Center Mai .0 $ 2fli�
Raleigh, North Carolina 27699-1617 CENTRAL FILES
DWR SECTION
Subject: 15A N. C. Admin. Code 213 .0506
Mayo Electric Generating Plant
National Pollutant Discharge Elimination System (NPDES) Number NCG120101
Monofill Stormwater Discharge Outfall Monitoring Report
Dear Sir or Madam:
Please find enclosed an amended semi-annual Monofill Stormwater Discharge Monitoring Report for
Permit Number NCG120101, SDO 003, for Duke Energy Progress, Inc. The Mayo Electric Generating
Plant Monofill became operational November 7, 2014. Original report submitted December 2014 for
sample date 1 1/17/2014. Report amended due to formatting discrepancy.
1 certify,, udder penalty! of law, that this document and all attachments were prepared under any direction or
supervision in accordance with a system designed to assure that qualified personnel properly gather- and evaluate
the information submitted. Based on nay inquire' 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 in)! knowledge and
belief, true, accurate, and complete. I ana aware that there are significant penalties for submitting false info ranation,
including the possibility of fines and imprisonment for knowing violations.
Please contact Mr. Shannon Langley at [phone], if there are any questions concerning the data in
this submittal.
Sincerely,
Enclosures
lwg J
J kv�
William J. Thacker- Manager
Mayo Electric Generating Plant

MONOFILL STORMWATER DISCHARGE OUTFALL SDO 003 (SDO)
MONITORING REPORT
Permit Number: NC NCG120101
FACILITY NAME
PERSON COLLECTING SAMPLE(S)
CERTIFIED LABORATORY(S)
Part A: Specific Monitoring Requirements
Mayo Steam Electric Plant
Easley, Slade, & Lea
Mayo Plant Lab Lab #
PACE Analytical Lab #
SAMPLES COLLECTED DURING CALENDAR YEAR: 2014 Amended
(This monitoring report shall be received by the pivision no later than 30 days from
the date the tocitity receives the sampling results tram the laboratory.]
County Person
hone No. 336-597-73 2
5064
40/503/530 (SIGNATURE OF PERMITEE OR E5IGNEE)
By this signature, I certify that this report is accurate
and complete to the best of my knowledge.
Outfall
No.
Date
Sample
Collected
01012
01027
01034
01051
01067
01077
01059
01092
Beryllium
Cadmium
Chromium
Lead
Nickel
Silver
Thallium
Zinc
mo/dd/yr
mg/I
mg/I
mg/I
mg/I
mg/I
mg/I
mg/I
mg/I
Out all SDO 003
11 17 2014
0.00074
<0.00005
0.0358
0.0054
0.0198
<0.00005
<0.0005
0.0812
Does this facility perform Vehicle Maintenance Activities using more than 55 gallons of new motor oil per month? No
( if yes complete Part B )
Part B: NA
Mail Original and one copy to:
STORM EVENT CHARACTERISTICS { if more than one storm event was sampled) Division of Water Resources
Date 11/17/2014 Date Attn: Central Files
Total Event Precipitation (inches) 0.67 Total Event Precipitation (inches) 1617 Mail Services Center
event duration (hours): 12 event duration (hours): 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 penalities for submitting false
information, including the possibility of fines and imprioonment for knowing violations." ���
William J. Thacker CtA D Date
Permittee ( nature of Permitteel

MONOFILL STORMWATER DISCHARGE OUTFALL SDO 003 (SDO)
MONITORING REPORT
Permit Number: NC NCG120101 SAMPLES COLLECTED DURING CALENDAR YEAR: 2014
FACILITY NAME Mayo Steam Electric Plant
PERSON COLLECTING SAMPLE(S) Easley, Slade, & Lea
CERTIFIED LABORATORY(S) Mayo Plant Lab Lab #
PACE Analytical Lab #
Part A: Specific Monitoring Requirements
{This monitoring report shall be received by the Oivision no later than 30 days from
the date the facility receives the sampling results from the laboratory.)
County Person
Phone No. 336-597-7332
5064 P
40/503/530 (SIGNATURE OF PERMITEE OR ESIGNEE)
By this signature, I certify that this report is accurate
and complete to the best of my knowledge.
Amended
Outfall
No.
Date
Sample
Collected
00530
31616
01002
01042
80103
71900
01147
00400
01097
01022
00945
00094
Total
Suspended
Solids
Fecal
Coliform
Arsenic
Total
Copper
Total
COD
Mercury
Selenium
PH
Antimony
Boron
Sulfate
Conductivity
mo/dd/yr
mg/I
CFU/100 ml
mg/I
mg/1
mg/I
mg/I
mg/I
std. units
mg/I
mg.1
mg/1
S/m
Out all SDO 003
11 17 2014
445
120
0.0021
0.0401
39.0
<0.0001
0,0015
7.55
<0.0005
<0.025
18.5
0.02707
Does this facility perform Vehicle Maintenance Activities using more than 55 gallons of new motor oil per month? No
( if yes complete Part B )
Part B: NA
Mail Original ana one copy to:
STORM EVENT CHARACTERISTICS ( if more than one storm event was sampled) Division of Water Resources
Date 11/17/2014 Date Attn: Central Files
Total Event Precipitation inches} 0.67 Total Event Precipitation (inches) 1617 Mail Services Center
event duration (hours): 12 event duration (hours): 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 penalities for submitting false
information, including the possibility of fines and imprioonment for knowing violations."
William J. Thacker
Permittee
61f'1111' 'j /'-)-47///' -
V V
( signA&I of Permittee)
Date

MONOFILL STORMWATER DISCHARGE OUTFALL SDO 003 (SDO)
MONITORING REPORT
Permit Number: NC NCG120101
FACILITY NAME
PERSON COLLECTING SAMPLE(S)
CERTIFIED LABORATORY(S)
Part A: Specific Monitoring Requirements
Mayo Steam Electric Plant
Easley, Slade, & Lea
Mayo Plant Lab Lab #t
PACE Analytical Lab #t
SAMPLES COLLECTED DURING CALENDAR YEAR: 2014 Amended
(This monitoring report shall be received by the Division no later than 30 days from
the Gate the taclllty receives the sampling results from the laboratory.)
County Person
hone No. 336-597-73 2
5064
40/503/530 SI NATURE OF PERMITEE OR SIGNEE)
By this signature, I certify that this rdpbrt is accurate
and complete to the best of my knowledge.
Outfall
No.
Date
Sample
Collected
00951
00940
00900
01007
01062
Floride
Chloride
Total
Hardness
as CaCO3
Barium
Molybdenum
mo/dd/yr
mg/I
mg/I
mg/I
mg/I
mg/1
Outfall SDO 003
11 17 2014
0.51
26.9
103
0.178
0.0014
Does this facility perform Vehicle Maintenance Activities using more than 55 gallons of new motor oil per month? No
( if yes complete Part B )
Part B: NA
Mail original and one copy to:
STORM EVENT CHARACTERISTICS ( if more than one storm event was sampled) Division of Water Resources
Date 11/17/2014 Date Attn: Central Files
Total Event Precipitation (inches) 0.67 Total Event Precipitation (inches) 1617 Mail Services Center
event duration (hours): 12 event duration (hours): 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. 9ased 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 penalams for submitting fal
information, including the possibility of fines and imprisonment for knowing violations.'
William J. Thacker JAed Date
Permittee na(e of rmittee) r

DUKE
ENERGY,
PROGRESS
Pile: Mayo 12520-R
JAN 2 9 2015
DECEIVED
FEB 0 3 2015
Mayo Steam Plant
Duke Energy Progress
10660 Boston Road
Roxboro, NC 27574
NC Division of Water Resources CENTRAL FILES
ATTENTION: Central Files DWR SECTION
1617 Mail Service Center
Raleigh, North Carolina 27699-1617
Subject: 15A N. C. Admin. Code 213.0506
Mayo Electric Generating Plant
National Pollutant Discharge Elimination System (NPDES) Number NCG 120101
Monofill Storrnwater Discharge Outfall Monitoring Report
Dear Sir or Madam:
Please find enclosed the semi-annuai Monofill Storrnwater Discharge Monitoring Report for Permit
Number NCG120101, SDO 001 and SDO 002, for Duke Energy Progress, Inc. The Mayo Electric
Generating Plant Monofill became operational November 7, 2014. This report fulfills the first sampling
requirement for SDO 001 and SDO 002.
I certify, raider 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 inquire, of the person or persons who manage the systenz, or those persons
directly responsible for gathering the information, the information submitted is, to the hest of my knowledge and
belief, true, accurate, and complete. 1 am aware that there a re significant penalties for submitting./alse
information, including the possibility of fines and inrpri.sonment for knowing violations.
Please contact Mr. Shannon Langley at [phone], if there are any questions concerning the data in
this submittal.
Sincerely,
Enclosures U�'& J i4v'L�
William J. Thacker- Manager
Mayo Electric Generating Plant

MONOFILL STORMWATER DISCHARGE OUITFALL SDO 002 (SDO)
MONITORING REPORT
Permit Number: NC NCG120101 SAMPLES COLLECTED DURING CALENDAR YEAR: 2014
FACILITY NAME Mayo Steam Electric Plant
PERSON COLLECTING SAMPLE(S) - Easley, Slade, & Talley
CERTIFIED LABORATORY(S) Mayo Plant Lab
PACE Analytical
Part A: Specific Monitoring Requirements
(This monitoring report shall he received by the Division no later than 30 days from
the date the facility receives the sampling results from the laboratory.)
County Person
Phoyle No. 336-597-7332
Lab # 5064/J�
Lab # 40/503/530 (SIGNATURE OF PERMITEE OR SIGNEE)
By this signature, I certify that this report is accurate
and complete to the best of my knowledge.
Outfall
No.
Date
Sample
Collected
00530
31616
01002
01042
80103
71.900
01147
00400
01097
01022
00945
00094
Total
Suspended
Solids
Fecal
Coliform
Arsenic
Total
Copper
Total
COD
Mercury
Selenium
pH
Antimony
Boron
Sulfate
Conductivity
mo/dd/yr
mg/I
MPN/100 mi
mg/1
mg/I
I mg/I
mg/I
mg/I
std. units
mg/I
mg.l
mg/1
S/m
Outfall SDO 002
12 29 2614
149
15.8
0.0011
0.0235
310
<0.0001
0.00055
7.38
<0.0005
<0.025
4.4
0.00723
Does this facility perform Vehicle Maintenance Activities using more than 55 gallons of new motor oil per month? No
( if yes complete Part B )
Part B: NA
Mail Original an one copy to:
STORM EVENT CHARACTERISTICS ( if more than one storm event was sampled) Division of Water Resources
Date 12/29/2014 Date Attn: Central Files
Total Event Precipitation (inches) 0.47" Total Event Precipitation (inches) 1617 Mail Services Center
event duration (hours): 10.5 event duration (hours): 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 penalities for submitting false
information, including the possibility of fines and imprioonment for knowing violations." r
William J. Thacker W1V A La&Date Z c� L t
Permittee ( Sig atur of Permittee)

MONOFILL STORMWATER DISCHARGE OUTFALL SDO 002 (SDO)
MONITORING REPORT
Permit Number: NC NCG120101 SAMPLES COLLECTED DURING CALENDAR YEAR: 2014
(This monitoring report shall be received by the Division no later than 30 days from
the date the tacility receives the sampling results trom the laboratory.)
FACILITY NAME Mayo Steam Electric Plant County Person
PERSON COLLECTING SAMPLE(S) Easley, Slade, & Talley Pone No. 336-597-7 2
CERTIFIED LABORATORY(S) Mayo Plant Lab Lab # 5064 f
PACE Analytical Lab # 40/503/530 (SIGNATURE OF PERMITEE OR SIGNEE)
By this signature, I certify that this re rt is accurate
and complete to the best of my knowledge.
Part A: Specific Monitoring Requirements
Outfall
No.
Date
Sample
Collected'
01012
01027
01034
01051
01067
01077
01059
01092
Beryllium
Cadmium
Chromium
Lead
Nickel
Silver
Thallium
Zinc
mo/dd/yr
mg/1
mg/I
mg/I
mg/I
mg/I
mg/I
mg/I
mg/I
Out all SDO 002
12 29 2014
0.00026
<0.00005
0.016
0.0024
0,010
<0.00005
<0.0005
0,0156
Does this facility perform Vehicle Maintenance Activities using more than 55 gallons of new motor oil per month?
( if yes complete Part B )
Part B: NA
STORM EVENT CHARACTERISTICS ( if more than one storm event was sampled)
Date 12/29/2014 Date
Total Event Precipitation (inches) 0.47 Total Event Precipitation (inches)
event duration (hours): 10.5 event duration (hours):
No
Mail Original and one copy to:
Division of Water Resources
Attn: Central Files
1617 Mail Services Center
Raleigh, North Carolina 27699-2617
" 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 an my inquiryof the person or persons who manage the system, or those persons directly responsibie for gathering
the information, the information submitted is, to the best of my knowiedge and belief, true, accurate, and complete. I am aware that there are significant penalits for submitting false
information, including the pcssibllity of fines and impdoonment for knowing violations." / I r\
William J. Thacker
Permittee ( Signature of er ittee
Date�S

MONOFILL STORMWATER DISCHARGE OUTFALL SDO 002 (SDO)
MONITORING REPORT
Permit Number: NC NCG120101
FACILITY NAME
PERSON COLLECTING SAMPLE(S)
CERTIFIED LABORATORY(S)
Part A: Specific Monitoring Requirements
Mayo Steam Electric Plant
Easley, Slade, & Talley
Mayo Plant Lab
PACE Analytical
Lab #
SAMPLES COLLECTED DURING CALENDAR YEAR: 2014
(This monitoring report shall be received by the Division no later than 30 days from
the date the taality receives the sampling results trom the laboratory.)
County Person
Phone No. 336-597-7 32
5064 r'
Lab # 40/503/530 (SIGNATURE OF PERMITEE O ESIGNEE)
By this signature, I certify that this ort is accurate
and complete to the best of my knowledge.
Outfall
No.
Date
Sample
Collected
00951
00940
00900
01007
01062
Floride
Chloride
Total
Hardness
as CaCO3
Barium
Molybdenum
mo/dd/yr
mg/I
mg/I
mg/I
mg/I
mg/I
Outfall SDO 002
12/29/20141
0.33
9.5
37.9
0,0806
<0.0005
Does this facility perform Vehicle Maintenance Activities using more than 55 gallons of new motor oil per month?
( if yes complete Part B )
Part B: NA
STORM EVENT CHARACTERISTICS ( if more than one storm event was sampled)
Date 12/29/2014 Date
Total Event Precipitation (inches) O— Total Event Precipitation (inches)
event duration {hours): 10.5 event duration (hours):
" 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 penallties for submitting false
information, including the possibility of fines and imprioonment for knowing violations." ' ^ I /
William J. Thacker (/��
Permittee Signa ur of Pe ittee)
No
Mail Original and one copy to:
Division of Water Resources
Attn: Central Files
1617 Mail Services Center
Raleigh, North Carolina 27699-1617
Date Z q,

MONOFILL STORMWATER DISCHARGE OUTFALL SDO 001 (SDO)
MONITORING REPORT
Permit Number: NC NCG120101 SAMPLES COLLECTED DURING CALENDAR YEAR: 2014
FACILITY NAME Mayo Steam Electric Plant
PER50N COLLECTING SAMPLE(S) Easley, Slade, & Talley
CERTIFIED LABORATORY(5) Mayo Plant Lab
PACE Analytical
Part A: Specific Monitoring Requirements
(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.)
County Person
Phone No. 336-597-7332
Lab # 5064
Lab # 40/503/530 (SIGNATURE OF PERMITEE OR 51GNEE)
By this signature, I certify that this re ort is accurate
and complete to the best of my knowledge.
Outfall
No.
Date
Sample
Collected
00530
31616
01002
01042
80103
71900
01147
00400
01097
01022
00945
00094
Total
Suspended
Solids
Fecal
Coliform
Arsenic
Total
Copper
Total
COD
Mercury
Selenium
pH
Antimony
Boron
Sulfate
Conductivity
mo/dd/yr
mg/I
MPN/100 ml
mg/I
mg/I
mg/I
mg/I
mg/I
std. units
mg/1
mg.1
mg/I
S/m
Outfall SOO 001
12717 2614
3.1
4.1
<0.0005
0.0014
8.0
<0.0001
<0.0005
6,92
<0.0005
<0.025
2.6
0.00628
Does this facility perform Vehicle Maintenance Activities using more than 55 gallons of new motor oil per month? No
( if yes complete Part B )
Part B: NA
mail original and one copy to:
STORM EVENT CHARACTERISTICS { if more than one storm event was sampled) Division of Water Resources
Date 12/16/2014 Date Attn: Central Files
Total Event Precipitation (inches) 0.12" Total Event Precipitation (inches) 1617 Mail Services Center
event duration (hours): 3 event duration (hours): Raleigh, North Carolina Z7699-1617
" 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 penalities for submitting false
information. includine the possibility of fines and imprioonment for knowing violations."
William J. Thacker Date
Permittee Si natt+re of Permittee)

MONOFILL STORMWATER DISCHARGE OUTFALL SOO 001(SDO)
MONITORING REPORT
Permit Number: NC NCG120101
FACILITY NAME
PERSON COLLECTING SAMPLE(S)
CERTIFIED LABORATORY(S)
Part A: Specific Monitoring Requirements
Mayo Steam Electric Plant
Easley, Slade, & Talley
Mayo Plant Lab Lab #
PACE Analytical Lab #
SAMPLES COLLECTED DURING CALENDAR YEAR: 2014
(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 IabOratOry.j
County Person
Phone No. 336-597-7332
5064 L
40/503/530 (SIGNATURE OF PERMITEE OR 51GNEE)
hat By this signature, I certify tthis rep is accurate
and complete to the best of my knowledge.
Outfall
No.
Date
Sample
Collected
01012
01027
01034
01051
01067
01077
01059
01092
Beryllium
Cadmium
Chromium
Lead
Nickel
Silver
Thallium
Zinc
mo/dd/yr
mg/I
mg/I
mg/I
mg/I
mg/I
mg/I
mg/I
mg/I
Out all SDO 001
12 16 2 114
<0.00005
<0.00005
0.0012
<0.0005
<0.00062
<0.00005
<0.0005
0.0084
Does this facility perform Vehicle Maintenance Activities using more than 55 gallons of new motor oil per month?
( if yes complete Part B )
Part B: NA
STORM EVENT CHARACTERISTICS (if more than one storm event was sampled)
Date 12/16/2014 Date
Total Event Precipitation (inches) 0�1211 Total Event Precipitation (inches)
event duration (hours): 3 event duration (hours):
No
Mail Original and one copy to:
Division of Water Resources
Attn: Central Files
1617 Mail Services 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 wlth 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 coml I am aware that there are significant penalities for submitting false
information, including the possibility of fines and imprisonment for knowing violations." A r 1 / J,
William J. Thacker
Permittee ( Signature Permittee)
Date Z /,

MONOFILL STORMWATER DISCHARGE OUTFALL 5DO 001(SDO)
MONITORING REPORT
Permit Number: NC NCG120101
FACILITY NAME
PERSON COLLECTING SAMPLE(S)
CERTIFIED LABORATORY(S)
Part A. Specific Monitoring Requirements
Mayo Steam Electric Plant
Easley, Slade, & Talley
Mayo Plant Lab Lab #
SAMPLES COLLECTED DURING CALENDAR YEAR: 2014
(This monitoring report shall be received by the Division no later than 30 days from
the date the tacility receives the sampling results from the laboratory.)
County Person
hone No. 336-597-7332
5064
PACE Analytical Lab # 40/503/530 (SIGNATURE OF PERMITEE OR ESIGNEE)
By this signature, I certify that this rep r is accurate
and complete to the best of my knowledge.
Outfall
No.
Date
Sample
Collected
00951
00940
00900
01007
01062
Floride
Chloride
Total
Hardness
as CaCO3
Barium
Molybdenum
mo/dd/yr
mg/I
mg/I
mg/l
mg/l
mg/I
Out all Soo 001
12 16 2014
<0.25
1.3
15.4
0.0131
<0.0005
Does this facility perform Vehicle Maintenance Activities using more than 55 gallons of new motor oil per month?
( if yes complete Part B )
Part B: NA
STORM EVENT CHARACTERISTICS ( if more than one storm event was sampled)
Date 12/16/2014 Date
Total Event Precipitation (inches) 0,12 Total Event Precipitation (inches)
event duration (hours): 3 event duration (hours):
"1 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 forgathering
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 penalities for submitting false
information, including the possibility of fines and imprioonment for knowing violations.' /I
William 1. Thacker � I (\
Permittee ( Sign tur of Pe mittee)
No
Mail Original and one copy to:
Division of Water Resources
Attn: Central Files
1617 Mail Services Center
Raleigh, North Carolina 27699-1617
Date Z i

AVZJ
_I
iv�A
North Carolina Department of Environment and Natural Resources
Pat McCrary
Governor
William J. Thacker
Duke Energy Progress, Inc.
Mayo Steam Electric Plant
10660 Boston Read
Roxboro, NC 27574
Dear Mr. Thacker:
May 20, 2014
John E, Skvarla, III
Secretary
RECEIV �
MAY 2 0 2014
CENTRAL FILES
DWQ/80G
Subject: General Permit No. NCG120000
Mayo Stearn Plant Monofill
CQC NCG120101
Person County
We received your request to modify the monitoring provisions in the above permit
Certificate of Coverage (CDC) on May 15, 2014. You requested to delay the initial sampling
period of several of the additional parameters by six months to allow time for the monofill to
begin full operation. Your request has been approved, and the modified monitoring schedule
is attached. Please replace the second page of your COC with the enclosed revision.
This permit does not affect the legal requirements to obtain other permits which may
be required by the Division of Energy, Mineral and Land Resources, or permits required by the
Division of Water Resources, Coastal Area Management Act, or any other federal or local:
governmental permit that may be required. If you have any questions concerning this' permit
modification, please contact Bradley Bennett at telephone [phone], or Bethany
Georgqulias at telephone [phone].
Sincerely,
for Tracy E. Davis, P.E., CPM'
cc: Toby Vinson, Land Quality Section
Dave Parnell, Raleigh Regional Office
Autumn Romanski, DWR Raleigh Regional Office
Sergei Chernikov, DWR Water Quality Permitting Section
Stormwater Permitting Program Files
DWR Central Files
enclosure
Division of Energy, Mineral, and Land Resources
Energy Section • Geological Survey Section • Land Quality Section
1612 Mail Service Center, Raleigh, North Carolina 27699-1612.919-707-92001 FAX: [phone]
512 North Salisbury Street, Raleigh, North Carolina 27604 • Internet: htt :11 ortal.ncdenr.or Iwebllrl
An Equal Opportunity 1 Affirmative Action Employer— 50% Recycled 110% Post Consumer Paper

Table 1 Analytical Monitoring Requirements
.Discharge,
Mess renient Preyuencyf ;
`'S m1ple
Sarnpye
Characteristics
Units
` '. :�, ,
--
TPb 2
Lt?Catigil3
Chemical Oxygen Demand
mg/1
.
isemi-annual
Grab
SDO
Fecal Coliform
4ter 100 ml
semi-annual
Grab
SDO
Total Suspended Solids
m 1
semi-annual
Grab
SDO
Arsenic (As)5
mg/1
semi-annual
Grab
SDO
Selenium Se S
mg/l
semi-annual
Grab
SDO
-Boron B 5
nng/1
semi-annual
Grab
SDO
S
S.U.
semi-annual
Grab
SDO
Conductivity
S rn
semi-annuai
Grab
SDO
Antimony (Sb), Total
mg/1
Grab
SDO
Recoverable
Barium (Sa); Toull
mg/1
Grab
SDO
Recoverable
Beryllium (Be), Tptal'
mg/1
Grab
SDO
Recoverable
Cadmium (Cd), Total
mg/1
Gram
SDO
Recoverable
Chromium (Cr), Total
mg/1
Grab
SDO
Recoverable
Copper (Cu), Total
nng/1
Grab
SDO
Recoverable
Lead (Pb), Total
rng/l
Grab
SDO
Recoverable
Once during Jul 1-Dec 31., 201.4;
Mercury (Hg), Total
mg/1
Grab.
SDO
Recoverable
Once during Jan 1-Jun 30, 2017
Molybdenum (Mo), Total
mg/1
Grab
SDO
Recoverable
Nickel (Ni), Total
mg/1
Grab
SDO
Recoverable
Silvei (Ag), Tofial
nng/l
Grab
SILO
Recoverable
Thallium.(TI), Total
mg/1
Grab
SOU
Recoverable
Zinc (Zn), Total
rng/l
Grab
SDO
Recoverable
Total Chloride(Cl).m
I.
Grab
$DO
Total Fluoride F
mg/1
Grab
SDO
Total Sulfate
MEZI
Grab .
SDO
Total Hardness
m 1
Grab
SDO
Total Rainfal14
inches
semi-annual
Rain
gauge
FoptUotes:
1 Measurement Frequency: Twice per year or during the specified period, during a measureable storm event.
2 f COC No. NCG120101
I effective January 6, 2014, modified May 20, 2014