NC0027359_Renewal (Application)_20170310

Water Resources
ENVIRONMENTAL QUALITY
March 10, 2017
Mr. David Sorrick, Senior Vice President
Tennessee Valley Authority
1101 Market Street, BR4A
Chattanooga, TN 37402
Subject: Permit Renewal
Application No. NCO027359
Hiwassee Hydro Plant
Cherokee County
Dear Mr. Sorrick:
ROY COOPER
Governor
MICHAEL S. REGAN
Acting Secretary
S. JAY ZIMMERMAN
Director
The Water Quality Permitting Section acknowledges receipt of your permit application and
supporting documentation received on February 27, 2017. The primary reviewer for this renewal
application is John Hennessy.
The primary reviewer will review your application, and he will contact you if additional
information is required to complete your permit renewal. Per G.S. 15OB-3 your current permit
does not expire until permit decision on the application is made. Continuation of the current permit
is contingent on timely and. sufficient application for renewal of the current permit.
Please respond in a timely manner to requests for additional information necessary to
complete the permit application. If you have any additional questions concerning renewal of the
subject permit, please contact John Hennessy at 919-807-6377 or [e-mail].
cc: Central Files
NPDES
Asheville Regional Office
Sincerely,
?ti" '74dond
Wren Thedford
Wastewater Branch
State of North Carolina I Environmental Quality I Water Resources
1617 Mail Service Center I Raleigh, North Carolina 27699-1617
919-807-6300

Tennessee Valley Authority, 1101 Market Street, BR4A, Chattanooga, Tennessee 37402
February 16, 2017
Ms. Wren Thedford
North Carolina Department of Environmental
Quality
Division of Water Resources
NPDES Unit
1617 Mail Service Center
Raleigh, North Carolina 27699-01617
Dear Ms. Thedford:
TENNESSEE VALLEY AUTHORITY (TVA) - HIWASSEE HYDRO (HIH) NPDES PERMIT NO.
NC0027359 - PERMIT RENEWAL APPLICATION
Enclosed are one signed original and two copies of a complete permit renewal application for
HIH. There have been no changes since the issuance of the last permit.
Solids may be removed from the station sumps manually or using a vacuum truck or similar
device. The waste is analyzed for hazardous constituents and characterized for appropriate
disposal. Any oil absorbent materials removed from the station sumps are handled in a similar
manner.
TVA requests that the following, which is consistent with language currently in General Permit
No. NCG500000 for discharges associated with hydroelectric operations, be included in the
renewed NPDES permit for HIH:
Submittal of monthly Discharge Monitoring Reports (DMRs) shall not be required except
upon demand by the Division. This section supersedes the requirement for submitting
monthly Discharge Monitoring Reports (DMRs) specified in Part U., Section D.2. of this
permit. Even though the submittal of the monthly monitoring reports to the Division is
suspended, all monitoring requirements remain. The data will be maintained on site for a
period of not less than three years.
TVA requests a 30 -day period between the issuance date and the effective date of the reissued
permit. If you have questions or need additional information, please contact Mike Stiefel by
email at [e-mail] or by phone at [phone].
Sincerely,
VerrVVI
�.�;.
heek
Senior Manager
Water Permits, Compliance, and Monitoring

Ms. Wren Thedford
Page 2
February 16, 2017
MBS:SMF
Enclosures
cc (Enclosures - Electronic Distribution):
C. B. Cothron, BR 4A -C
A. R. Deimling, RAC 1A -C
A. L. Moore, OHP 1A-BNT
C. M. Richards, MR BA -C
ECM, ENVrecords

NPDES PERMIT APPLICATION - SHORT FORM C -Minor Industrial
Minor industrial, manufacturing and commercial facilities.
Mail the complete application to:
N. C. Department of Environment and Natural Resources
Division of Water Quality / NPDES Unit
1617 Mail Service Center, Raleigh, NC 27699-1617
NPDES Permit Number INCO027359
Please print or type.
1. Contact Information:
Owner Name
Facility Name
Mailing Address
City
State / Zip Code
Telephone Number
Fax Number
e-mail Address
Tennessee Valley Authority - David W. Sorrick, Sr. VP Power
Operations
Hiwassee Hydro Plant
1101 Market Street, LP 3K
Chattanooga
Tennessee 37402
[phone]
[phone]
[e-mail]
2. Location of facility producing discharge:
Check here if same as above ❑
Street Address or State Road
City
State / Zip Code
County
600 Powerhouse Road
near Murphy
North Carolina, 28906
Cherokee
3. Operator Information:
Name of the firm, consultant or other entity that operates the facility. (Note that this is not referring to the
Operator in Responsible Charge or ORC)
Name Tennessee Valley Authority
Mailing Address 1101 Market Street, LP 3K
City Chattanooga
State / Zip Code Tennessee 37402
Telephone Number [phone]
Fax Number [phone]
4. Ownership Status:
Page 1 of 5 C -MI 10/08

NPDES PERMIT APPLICATION - SHORT FORM C - Minor Industrial
Minor industrial, manufacturing and commercial facilities.
Federal ® State ❑ Private ❑ Public ❑
5. Standard Industrial Classification (SIC) code(s): 4911 - Electric Services
6. Number of employees: 25
7. Describe the treatment system List all installed waste treatment components with capacities,
describe the processes that generate wastewaters. If the space provided is not sufficient attach a
separate sheet of paper with the system description.
Water discharged from Outfalls 001, 002, and 005 includes floor drains, wheel pit
leakage, draft tube unwatering operations, and lower and upper gallery drains collected in
sumps. Refer to the enclosed flow schematic. Oil absorbent pads are used in sumps and
points of equipment oil leaks. These pads are changed at least once per quarter in
addition to the removal of sediment to ensure that excessive pollutants are not
discharged to surface waters of the State. It is assumed that the oil absorbent pads treat
100% of the volume before discharge at normal flow.
8. Is facility covered under federal effluent limitation guidelines? No ® Yes ❑
If yes, specify the category?
9. Principal product(s) produced: Electric Power
Principal raw material(s) consumed: N/A
Briefly describe the manufacturing process(es):
TVA's conventional hydro plants typically include a dam to control the flow of a river, a
powerhouse containing turbines and generators to make electricity, a switchyard to step up the
electricity's voltage for distribution to customers, and a large reservoir of water behind the dam.
Water from the upper reservoir flows through a penstock (a large pipe connecting the reservoir
to the powerhouse) impacting the blades of a turbine. Water impacting the blades makes the
turbine rotate. A large diameter shaft connects the rotating turbine to a generator in the
powerhouse. The generator consists of a large rotating electromagnet (driven by the turbine)
located in the middle of an even larger set of stationary wire coils. When running at the proper
speed (typically around 100 revolutions per minute for TVA hydro generators), electricity is
produced in the coils at anywhere from about 13,000 to 23,000 volts. Generator leads take the
electricity to the switchyard where the voltage is increased and put into the TVA transmission
system for delivery to distributors across the Tennessee Valley. The water used to turn the
turbine then flows out of the powerhouse in a draft tube where it is released into the water
supply. Hiwassee Hydro Plant has two units, one conventional hydroelectric unit, and one
reversible pump storage/ hydroelectric unit.
Page 2 of 5 C -MI 10108

NPDES PERMIT APPLICATION - SHORT FORM C - Minor Industrial
Minor industrial, manufacturing and commercial facilities.
10. Amount of principal product produced or raw material consumed
List s eci c amounts consumed and/or units of roductton over the last three ears
11. Frequency of discharge: Continuous* ® Intermittent ❑
If intermittent:
Days per week discharge occurs: Duration:
* While individual discharges may not flow continuously, it is unlikely that there would be no discharge from
any outfall on any given day unless both units were in outage.
12. Types of wastewater discharged to surface waters only
Discharge
Product Produced or Raw Material
Consumed
AVERAGE
Product Produced or Raw Material
Consumed
PEAK
per Day
858 mWh generation
3,743 mWh generation
per Month
26,113 mWh generation
88,521 mWh generation
per Year
313,352 mWh generation
421,134 mWh generation
11. Frequency of discharge: Continuous* ® Intermittent ❑
If intermittent:
Days per week discharge occurs: Duration:
* While individual discharges may not flow continuously, it is unlikely that there would be no discharge from
any outfall on any given day unless both units were in outage.
12. Types of wastewater discharged to surface waters only
Discharge
Flow*
GALLONS PER DAY
Sanitary - monthly average
No discharge to surface water (subsurface disposal)
Utility water, etc. - monthly average
N/A
Process water - monthly average
432,000 (Outfall 001), 7,200,000 (Outfall 002**), and
1,641,000 (Outfall 005)
Stormwater - monthly average
N/A
Other - monthly average
Explain: Noncontact Cooling Water
4,250,000
Monthly Average
5,950,000
total discharge (all types)
Note: stows are estimated for average operating conditions using pump rated capacity or design capacity. "Umvatering
operations (Outfall 002) are intermittent and typically occur approximately once every two years per unit. Sec attached flow
schematic.
13. Number of separate discharge points: 5 Outfall Identification number(s) Outfalls 001,
002, 003, 004, and 005
14. Name of receiving stream(s) (Provide a map shouring the exact location of each outfall, including
latitude and longitude):
Hiwassee River (See attached map)
Page 3 of 5 C -MI 10108

NPDES PERMIT APPLICATION — SHORT FORM C — Minor Industrial
Minor industrial, manufacturing and commercial facilities.
15. Effluent Data [for new or proposed discharges]
Provide data for the parameters listed. Temperature and pH shall be grab samples, for all other parameters 24-hour
composite sampling shall be used. If more than one analysis is reported, report daily maximum and monthly average.
If only one analysis is reported, report as daily maximum.
NOTE: Permittees requesting renewal should complete the table ONLY for the parameters
...,..e..t1.• ...,...it-. 4 IRo n"ct A .,onrc of oft7fiont rlfftlf_
Parameter
Daily
Maximum
Monthly
Average
Units of
Measurement
Biochemical Oxygen Demand (BOD5)
Chemical Oxygen Demand (COD)
Total Organic Carbon
TVA is applying for permit renewal.
Currently no analytical monitoring is
required. Best Management Practices have
been implemented and visual inspections of
the tailrace have been performed in
accordance with the current NPDES permit.
Total Suspended Solids
Ammonia as N
Temperature (Summer)
Temperature (Winter)
pH
Fecal Coliform (If sanitary waste is
present)
Total Residual Chlorine (if chlorine is
used)
16. List all permits, construction approvals and/or applications (check all that apply and provide permit
numbers or check none if not applicableP
Type Permit Number Type Permit Number
Hazardous Waste (RCRA)
UIC (SDWA)
NPDES
PSD (CAA)
Non -attainment program (CAA)
NCO027359
NESHAPS (CAA)
Ocean Dumping (MPRSA)
Dredge or fill (Section 404 or CWA)
Other
17. List any chemicals that may be discharged (Please list and explain source and potential
amounts.)
Small amounts of Oil and Grease may be discharged from outfalls as oil containing equipment
is located on site. Visual monitoring has occurred and BMPs have been implemented
under the current permit. No visible sheens have been observed.
Page 4 of 5 C -MI 10/08

NPDES PERMIT APPLICATION - SHORT FORM C - Minor Industrial
Minor industrial, manufacturing and commercial facilities.
18. Is this facility located on Indian country? (check one)
Yes ❑ No
19. Applicant Certification
I certify that I am familiar with the information contained in the application and that to the
best of my knowledge and belief such information is true, complete, and accurate.
North Carolina General Statute 143-215.6 (b)(2) provides that: Any person who knowingly makes any false
statement representation, or certification in any application, record, report, plan, or other document files or
required to be maintained under Article 21 or regulations of the Environmental Management Commission
implementing that Article, or who falsifies, tampers with, or knowingly renders inaccurate any recording or
monitoring device or method required to be operated or maintained under Article 21 or regulations of the
Environmental Management Commission implementing that Article, shall be guilty of a misdemeanor punishable
by a fine not to exceed $25,000, or by imprisonment not to exceed six months, or by both. (18 U.S.C. Section
1001 provides a punishment by a fine of not more than $25,000 or imprisonment not more than 5 years, or both,
for a similar offense.)
Page 5 of 5 C -MI 10/08

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Outfalls 001 - 005
Tennessee Valley Authority
Hiwassee Hydro Plant — NCO027359
Sate Grid/Quad: G2NW/Unaka, NC Drainage Basin: Hiwassee River
Latitude: 35°09' 01" N
Longitude: 840 10'41"W
Receivin�Stream: Hiwassee River
Stream Class: C
�r NPDES Permit No. NC0027359
Cherokee County

Intake from Hiwassee River
Upper
Gallery Drains
..
Outfall
Lower
1.440 MGD
Sum ^
................................ p...........................ll..........;......................................� 005
Gallery Drains 1.641 MGD
Unit 2 Floor DrainsStation
.......................... .0
Sump...............................,
0.2016 MGD
Unit 2 Wheel Pit
Leakage
Unit 1 2.052 MGD
_
Generator Air& .—.—.—.—.—.—•—•—•—•—•—•—•—•—•—•—•—•—•—•—•—•—•-> 003
Bearing Cooling Water......................................................... Unit 2 2,606 MGD 004
Draft Tube Unwatering
Unwatering Operations Sum -0 .................................................. � 002
p 7.200 MGD
Unit 1 Floor Drains
And Wheel Pit Leakage
Station
Sump
Potable —�I Sanitary Sewage Drains I Septic Tank
Water ....
Symbols:
Raw River Water, Potable Water, Precipitation, Leakage, or Ground Water
— Non -Contact Cooling Water
"•••""" Other Wastewater
OMotor -Driven Pump
Notes:
1. All effluents discharge into the Hiwassee River.
2. Flows are based on pump -rated capacities and maximum design flows.
................................ 30. 001
0.432 MGD
Subsurface Disposal Field
Tennessee Valley Authority
Hiwassee Hydro Plant
NPDES Permit No. NC 0027359
Cherokee County, North Carolina
February 2017