NC0027332_Fact Sheet_20180730

Fact Sheet
Renewal 2018 -- NPDES Permit NC0027332
Page 1

DEQ/ DWR / NPDES
EXPEDITED FACT SHEET - NPDES PERMIT DEVELOPMENT
NPDES Permit NC0027332
Derek Denard, Compliance & Expedited Permitting Unit / 919-807-6307 30Jul2018
Facility Information
Applicant/Facility Name Tennessee Valley Authority/ Chatuge Hydro Plant
Applicant Address 1101 Market Street, BR4A, Chattanooga, TN 37402
Facility Address Chatuge Dam Road, Hayesville, NC 28904
Permitted Flow (MGD) Not limited
Type of Waste 100% industrial; SIC: 4911 Primary: 48
cooling waters and wastewaters associated with Hydroelectric operations
Facility Class PCNC County Clay
Permit Status Renewal Regional Office ARO
Stream Characteristics
Receiving Stream Hiwassee River Stream Classification C
Stream Segment 1-(15) Drainage basin Hiwassee
Summer 7Q10 (cfs) – Subbasin
HUC
04-05-01
060200020203
Winter 7Q10 (cfs) – Use Support 2014: No data 30Q2 (cfs) – 303(d) Listed
Average Flow (cfs) – State Grid G3SE
IWC (%) – USGS Topo Quad Hayesville, NC
FACILITY SUMMARY: The Chatuge Hydro Plant produces electricity via hydraulic turbine generation.
The facility produces an average of 81 megawatt-hours per day of power, with peak power generation at
336 megawatt-hours per day.

The plant has three permitted outfalls as follows:

Outfall monthly average flow (gpd)
001: waters from the station sump 360,000
002: waters from the unwatering sump 600,000
003: once through cooling water 648,000
Total 1,608,000
RENEWAL SUMMARY:
We have made the following updates for the final permit:
1. The facility classification Physical Chemical Not Classified has been added to the effluent page.
2. Footnote 1 for Outfalls 001, 002 and 003 has been updated to the following:
Electronic Reporting of Discharge Monitoring Reports (eDMR):
a. The Permittee shall submit Discharge Monitoring Reports electronically using NC DWR’s
eDMR application system. See Condition A. (5.).
b. Monitoring results obtained during the previous calendar quarter shall be recorded and
reported in eDMR no later than the 30th day following the completed reporting period. The
first DMR is due on the 30th day of the month following the calendar quarter in which the
permit was issued. [Quarterly reporting for this permit is in exception to NPDES standard
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conditions found in Part I, A. (5.) and Part II, D. (2.). wherein monthly reporting is
indicated.]
3. Foot 5 for Outfalls 001 and 002 has been updated to read “In lieu of monitoring pH and O&G”.
The Division has made the following updates for permit renewal:
4. The facility map has been updated.
5. Regulatory citations have been added.
6. Electronic reporting of discharge monitoring reports (eDMR) has been added in Section A. (5.).
7. The sample types for Oil & Grease, pH and Temperature have been indicated as grab.
8. A new parameter Free Oil Visual Sheen [51689] has been added to the effluent tables for Outfalls
001 and 002 to record visual inspection of the tailrace. Monitoring for this parameter is at least once
per quarter by estimate. See footnote 3 in the permit for more information.
9. For Outfalls 001 & 002, Footnote 4 has been added as a new requirement: If oil sheen or visible
foam (other than trace amounts) are present, monitoring of the following parameters is required
until presence of oil or foam is abated: pH and O&G.
10. For Outfalls 001 & 002, Footnote 5 has been added indicating that BMPs can be employed in lieu
of monitoring.
11. For Outfall 003, semi-annual monitoring has been indicated for Temperature and pH.
12. Special Condition A. (4.) for Use of Biocides has been added.
PARAMETERS OF CONCERN:

For Outfalls 001 & 002:
EFFLUENT CHARACTERISTICS
[parameter codes]
LIMITS MONITORING REQUIREMENTS 1
Monthly
Average
Daily
Maximum
Measurement
Frequency
Sample
Type
Sample
Location2
Flow (MGD) 50050 Monitor & Report a Quarterly Estimate E
Free Oil Visual Sheen (yes=1 no=0) 3,4 51689 Monitor & Report Quarterly Estimate E
pH (su) 4,5,6 00400 Monitor & Report 6, b Footnotes 4, 5 Grab c E
Oil & Grease (O&G) (mg/L) 4,5 00556 15 mg/L d 20 mg/L d Footnotes 4, 5 Grab c E
Footnotes:
1. Electronic Reporting of Discharge Monitoring Reports (eDMR):
a. The Permittee shall submit Discharge Monitoring Reports electronically using NC DWR’s eDMR application
system. See Condition A. (5.).
b. Monitoring results obtained during the previous calendar quarter shall be recorded and reported in eDMR no later
than the 30th day following the completed reporting period. The first DMR is due on the 30th day of the month
following the calendar quarter in which the permit was issued. [Quarterly reporting for this permit is in exception
to NPDES standard conditions found in Part I, A. (5.) and Part II, D. (2.). wherein monthly reporting is indicated.]
2. Sample locations: E – Effluent
3. Free Oil Visual Sheen:
a. The tailrace shall be visually inspected for oil sheens at least once a quarter at this hydroelectric facility.
b. Chemical wheel pit cleaning is permitted on a monthly basis. When cleaning of the wheel pit occurs, the tailrace
shall be inspected visually for foam and oil. Cleaning shall be conducted only with pre-approved solvents. Should
the Permittee wish to change cleaning solvents, a written request should be made to the Division including the
MSDS for the proposed solvent. See Use of Biocides – Special Condition A. (4.).
c. Free Oil Visual Sheen shall be reported by entry of the one of the following codes into eDMR:
Yes = 1 (Oil Sheen Visible)
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No = 0 (Oil Sheen Not Visible).
4. If oil sheen or visible foam (other than trace amounts) are present, monitoring of the following parameters is required
until presence of oil or foam is abated: pH and O&G.
5. Best Management Practices (BMPs) f: In lieu of monitoring pH and O&G, BMPs must be employed to ensure that
excessive pollutants are not discharged to the surface waters of the State. These practices should include, as a
minimum, changing oil absorbent pads quarterly and cleaning accumulated sediment in the bottom of the sump
routinely. When these activities occur confirmation that BMPs have been followed shall be clearly noted in the
comments section of eDMR.
6. The pH shall not be less than 6.0 standard units nor greater than 9.0 standard units unless ambient river conditions
prevent compliance with this range.
Conditions:
• This permit does not limit mechanical cleaning operations, which do not contribute any wastewater to the discharge.
Non-discharging cleaning operations may be conducted as often as necessary to ensure safety and proper facility
operation.
• There shall be no discharge of floating solids or visible foam (other than trace amounts) in the effluent.
• All samples collected should be form a representative discharge event, a measurable discharge event that results in an
actual discharge from the permitted discharge outfall.
Permitting Notes:
a. Flow is not limited.
b. 15A NCAC 02B .0211 (14) pH: shall be normal for the waters in the area, which range between 6.0 and 9.0
except that swamp waters may have a pH as low as 4.3 if it is the result of natural conditions;
c. Grab sampling is required by 15A NCAC 02B .0505 (c)(3)(C).
d. Technology based limits for Oil & Grease.
e. 15A NCAC 02B .0211 (12) Oils, deleterious substances, colored, or other wastes: only such amounts as
shall not render the waters injurious to public health, secondary recreation, or to aquatic life and wildlife, or
adversely affect the palatability of fish, aesthetic quality, or impair the waters for any designated uses. For
the purpose of implementing this Rule, oils, deleterious substances, colored, or other wastes shall include
substances that cause a film or sheen upon or discoloration of the surface of the water or adjoining
shorelines pursuant to 40 CFR 110.3(a)-(b) which are hereby incorporated by reference including any
subsequent amendments and additions. This material is available, free of charge, at: http://www.ecfr.gov/
f. The following is information from the EPA webpage Learn About Effluent Guidelines
(https://www.epa.gov/eg/learn-about-effluent-guidelines):
“BMPs: Best Management Practices are defined as a permit condition used in place of, or in
conjunction with effluent limitations, to prevent or control the discharge of pollutants. BMPs may
include a schedule of activities, prohibition of practices, maintenance procedure, or other management
practice. Sections 304(e), 308(a), 402(a), and 501(a) of the CWA authorize EPA to prescribe BMPs as
part of Effluent Guidelines and Standards or as part of a permit.
BMP regulations:
• Direct dischargers: 40 CFR 122.2, 40 CFR 122.44(k)
• Indirect dischargers: 40 CFR 403.3(e)
CWA section 304(e) authorizes EPA to include BMPs in Effluent Guidelines for certain toxic or
hazardous pollutants for the purpose of controlling "plant site runoff, spillage or leaks, sludge or waste
disposal, and drainage from raw material storage." CWA section 402(a)(1) and 40 CFR 122.44(k) also
provide for BMPs to control or abate the discharge of pollutants when numeric limitations and
standards are infeasible.”

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Renewal 2018 -- NPDES NC0027332
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For Outfall 003:
EFFLUENT CHARACTERISTICS
[parameter codes]
LIMITS MONITORING REQUIREMENTS 1
Monthly
Average
Daily
Maximum
Measurement
Frequency
Sample
Type
Sample
Location2
Flow (MGD) 50050 Monitor & Report g Semi-annually Estimate E
Temperate (°C) 3 00010 Monitor & Report 3, h Semi-annually Grab i E
pH (su) 4 00400 Monitor & Report 4, j Semi-annually Grab i E
Footnotes:
1. Electronic Reporting of Discharge Monitoring Reports (eDMR):
a. The Permittee shall submit Discharge Monitoring Reports electronically using NC DWR’s eDMR application
system. See Condition A. (5.).
c. Monitoring results obtained during the previous calendar quarter shall be recorded and reported in eDMR no later
than the 30th day following the completed reporting period. The first DMR is due on the 30th day of the month
following the calendar quarter in which the permit was issued. [Quarterly reporting for this permit is in exception
to NPDES standard conditions found in Part I, A. (5.) and Part II, D. (2.). wherein monthly reporting is indicated.]
2. Sample locations: E – Effluent
3. The temperature of the effluent will be regulated so that the temperature of the receiving stream does not increase
more than 2.8°C above the natural water temperature. Receiving water temperature shall not exceed a maximum of
29°C due to the facility’s operation. h
4. The pH shall not be less than 6.0 standard units nor greater than 9.0 standard units unless ambient river conditions
prevent compliance with this range. j
Conditions:
• All non-contact cooling water sample locations shall provide representative samples of the discharge and require
sampling prior to discharge commingling with any other waters or substances, such as stormwater or surface water to
enable characterization of a pollutant of concern.
• There shall be no discharge of floating solids or visible foam (other than trace amounts) in the effluent.
• All samples collected should be form a representative discharge event, a measurable discharge event that results in an
actual discharge from the permitted discharge outfall.

Permitting Notes:
g. Flow is not limited.
h. 15A NCAC 02B .0211 (18) Temperature: not to exceed 2.8 degrees C (5.04 degrees F) above the
natural water temperature, and in no case to exceed 29 degrees C (84.2 degrees F) for mountain and
upper piedmont waters and 32 degrees C (89.6 degrees F) for lower piedmont and coastal plain Waters;
the temperature for trout waters shall not be increased by more than 0.5 degrees C (0.9 degrees F) due
to the discharge of heated liquids, but in no case to exceed 20 degrees C (68 degrees F).
i. Grab sampling is required by 15A NCAC 02B .0505 (c)(3)(C).
j. 15A NCAC 02B .0211 (14) pH: shall be normal for the waters in the area, which range between 6.0
and 9.0 except that swamp waters may have a pH as low as 4.3 if it is the result of natural conditions.

COMPLIANCE HISTORY: No compliance issues noticed with the past five (5) years.
DATA SUMMARY:
Sep2013-Feb2018
Parameter Outfall Max Min Average Count UoM
50050 - Flow, in conduit or thru treatment plant 001 0.36 0.36 0.36 285 mgd
002 2.4 2.4 2.4 15 mgd
003 0.648 0.648 0.648 100 mgd