NC0004987_Comments_19930312

.I
State of North Carolina
(Department of Environment, Health, and Natural Resources
Division of Environmental Management
512 North Salisbury Street - Raleigh, North Carolina 27604
James B. Hunt, Jr., Governor Jonathan B. Howes, Secretary
Ms. Norma Atherton
Duke Power Company
Generation Services Department
13339 Hagers Ferry Road
Huntersville, NC 28078-7929
Dear Ms. Atherton:
March 12, 1993
Subject: Draft NPDES Comments/Marshall Steam
NPDES Permit No. NC0004987
Catawba County
This office is in receipt of your letter dated January 29, 1993 regarding comments on the
NPDES draft permit. The Division of Environmental Management (DEM) appreciates your review
and comments and offers the following responses to your requests. The responses will be in the
same order as in the January 29 letter.
1. The stream classification listed in the public notice was noted to be wrong. The correct
stream classification is in the permit and is WS -IV & B CA.
2. The designation of each outfall is noted and is stated correctly on the Supplement to permit
cover sheet.
3. Your request for the footnote for Pollutant Analysis to be located on the first page with, the
parameter listing cannot be handled presently. Due to the NPDES 'permit writing system DEM is
currently using, this correction cannot be made. The shell has a zone set aside for parameters and
after the zone is full, the remaining parameters will scroll over to the next page. This problem
should be corrected with our new permit writing system and hopefully will be corrected next
permit cycle.
4. A footnote has been added for the Total Residual Chlorine. It states, °" Monitoring
requirements only apply when chlorine is added to the cooling water. If chlorine is added then
monitoring applies, if not then monitoring does not apply.
5. Over the events of issuing permits, we come across boilerplate errors or clarifications
that need to be corrected or modified. DEM will place your comments on the clarification of cause
for the next review and, if appropriate, modify the language to provide better understanding.
Regional Offices
Asheville Fayetteville Mooresville Raleigh Washington Wilmington Winston-Salem
704/251-6208 919/486-1541 704/663-1699 919/571-4700 919/946-6481 919/395-3900 919/896-7007
Pollution Prevention Pays
P.O. Box 29535, Raleigh, North Carolina 27626-0535 Telephone [phone]
An Equal Opportunity Affirmative Action Employer

Page 2
March 12, 1993
Ms. Atherton
V. In the previous permit, a 15 day written report of the non-compliance was required but
because of comments from other permittees the error was called to our attention and was modified
In the procedure as stated in number 5 above. In 40 CFR 122.41(I)(6)(i) it states that " Any
Information shall be provided orally within 24 hours from the time the permittee becames aware
of the circumstances." and "A written submission shall also be provided within 5 days of the time
the permittee becomes aware of the circumstances." As the Federal Guidelines states the 5 day
reporting time must remain and the oral report within twenty four hours must also remain due to
the guidelines and for the protection of the receiving waters. If a non-compliance action occurs on
a. Friday evening, an oral report Monday morning might be too late for any type of preventive
action. Additionally, the NPDES program is delegated by the U.S. Environmental. Protection Agency
to the State. As a delegated state, all permits issued must be able to be enforced by EPA and must
conform to the federal requirements and therefore the subject language was corrected to reflect
the Code of Federal Regulations.
8. Section M of Part III "definition of upsets" was redundant and has been removed from Part
III.
9. The parenthesis as written are correct In the first section but in the second referenced
part the parenthesis was removed.
10. In Part III "Other Requirements", Section Q; all of the requested changes have been made.
Copper complexer and -citric acid was added to 0(6)(b) and part (c) was added to state "
Neutralization step: soda ash and trisodiumphosphate". The typographical errors in section Q(8)
were corrected.
11. The typographical error was corrected.
Other Comments:
1. The biocide approval request has been received and a separate letter will be sent with
approval or disapproval of the biocides when the Aquatic Toxicity Group completes their
assessment.
2. Rainfall event sampling .deletion as requested in the January 19, 1.993 letter has been
approved and removed from the NPDES permit for Marshall Steam Station.
In accordance with your application for discharge ,permit received on September 19, 1992
we are forwarding herewith the subject state - NPDES permit. This permit is issued pursuant to
the requirements of North Carolina General Statute 143-215 .1 and the Memorandum of
Agreement between North Carolina and the US Environmental Protection agency dated December 6,
1983.
If any parts, measurement frequencies or sampling requirements contained in this permit
are unacceptable to you, you have the right to an adjudicatory hearing upon written request
within thirty (30) days following receipt of this letter. This request must be in the form of a
written petition, conforming to Chapter 150B of the North Carolina General Statutes, and filed
with the Office of Administrative Hearings, Post Office Drawer 27447, Raleigh, North Carolina
27611 -7447. Unless such demand is made,,this decision shall be final and binding.

t c `
Page 3
March 12, 1993
Ms. Atherton
Please take notice this permit is not transferable. Part II, B.2. addresses the requirements
to be followed in case of change in ownership or control of this discharge. This permit does not
affect the legal requirements to obtain other permits which may be required by the Division of
Environmental Management or permits required by the Division of Land Resources, Coastal Area
Management Act or any other Federal or Local governmental permit that may be required.
If you have any questions, please contact Mr. Randy Kepler at telephone number 919/733-
5083.
cc. Mr. Jim Patrick, EPA
Mooresville Regional Office
Permits and Engineering Unit
Central Files
M.D. McIntosh, Duke Power Company
P.O. Box 210
Terrell, NC 28682
Sincerely,
Original Signed By
Coleen H. Sullins
A. Preston Howard, Jr., P.E., Acting Director
Division of Environmental Management

Permit No. NC0004987
STATE OF NORTH CAROLINA '
DEPARTMENT OF ENVIRONMENT, HEALTH;AND NATURAL RESOURCES
DIV ZION OF ENVIRONMENTAL MANAGEMENT
PERMIT
TO DISCHARGE WASTEWATER UNDER THE
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, as amended,
Duke Power Company
is hereby authorized to discharge wastewater from a facility located at
Marshall Steam Station
Terrell
Catawba County
to receiving waters designated as the Catawba River (Lake Norman) in the Catawba River Basin
in accordance with effluent limitations, monitoring requirements, and other conditions set forth in
Parts I, Ii, and III hereof.
This permit shall become effective April 1, 1993
This permit and the authorization to discharge shall expire at midnight on June 30, 1995
Signed this day March 12, 1993
Original Signed By
Coleen H. Sullins
A. Preston Howard, Jr., Acting Director
Division of Environmental Management
By Authority of the Environmental Management Commission

z . `
Permit No. NCO004987
SUPPLEMENT TO PERM i COVER SHEET
Duke Power Company
is hereby authorized to:
1. Continue to discharge once -through cooling water (outfall 001); an ash pond discharge (outfall
002) consisting of domestic wastewater, wastewater from yard sumps, ash removal lines,
stormwater runoff, metal cleaning wastewater, and intake screen backwash; and a non -contact
cooling water discharge (003) consisting of wastewater from an air conditioning unit located at
Marshall Steam Station, ,Terrell, Catawba County (See Part III of this Permit), and
2. Discharge from said treatment works at the location specified on the attached map into the
Catawba River (Lake Norman) which is classified Class WS -IV & B CA waters in the Catawba
River Basin.

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A. (). EFFLUENT LIMITATIONS AND MONITORING REQUIREMENTS FINAL
Permit No. NC0004987
During the period beginning on the effective date of the permit and lasting until expiration, the Permittee is authorized to discharge from
outfall(s) serial number 001, once through cooling water. Such discharges shall be limited and monitored by the permittee as specified below:
Effluent Cheracterlstle. Discharge Limltationi
Lbs/clay Units (saeclfv
Mon. Avg. Deily Max Mon. Avg. Dally Max.
Flown
Temperature °C(°F)••• 33.3°C (92°F)
* Sample Location: E • Effluent
,'**Or similar reading
✓ ***During the period July 1 to October 15, 34.4°C (94°F) is permitted.
Monitoring Reauirementi
Measurement Samai5am21e
Freauencv Tvee ,location
Daily Pump Logs" E
Daily
Grab E
t/Chlorination of the once through cooling water shall not be allowed at this facility, Should Duke Power wish to chlorinate its once through
cooling water, a permit modification must be requested and received prior to commencing chlorination.
The Regional Administrator has determined pursuant to Section 316(a) of the Act that the thermal component of the discharge assures the
protection and propagation of a balanced, indigenous population of shellfish and wildlife in and on the receiving body of water. Water quality
temperature standards must be maintained outside of the approved 316(a) zone.
,,- There shall be no discharge of floating solids or visible foam in other than trace amounts.

A. (). EFFLUENT LIMITATIONS AND MONITORING REQUIREMENTS FINAL
Permit No. NC0004987
During the period beginning on the effective date of the permit and lasting until expiration, the Permittee is authorized to discharge from
outfall(s) serial number 002, Ash settling pond. Such discharges shall be limited and monitored by the permittee as specified below:
Effluent Chareaterlstle.
Discharge Llmltatloni
Monitoring
Requirements
Lbs/de-
Units
(speclfv
Measurement
Sample
*Sample
Mon. Avg D®Ily
Mex Mon. Avg.
Dally Max.
Freguencv
Tvoe
)socatlon
Flow
Weekly
Pump Logs (+)
E
-Oil and Grgasa.
9.0 mg/1
12.0 mg/I
2/Month
Grab
E
Total Suspended ResiduO**
20.0_mg/I
_65.0 mg/I
2/Month
Grab
E
&-Total Co r __ _ _
1.0_ m-g/I;
1.0 mg/I
2/Month
Grab
E
Total Iron _ _ _ — _
1..0 m9/1
.1.0 mg/I
2/Month
Grab
E
YTotal Arsenic
_ yo3
4L5.0 µg/I
2/Month
Grab
E
-Total Selenium
yam.
_41_0 µg/l
2/Month
Grab
E
Zinc
Monthly
Grab
E
,,Total Nitrogen (NO2+NO3+TKN)
Monthly
Grab
E
'Total Phosphorus
Monthly
Grab
E
- Chronic Toxicity"
Quarterly
Grab
E
* Sample Locations: E - Effluent
"Effluent sampling shall be conducted at the discharge from the ash settling pond prior tD mixing with any other wastestream.
o.** Chronic Toxicity (Ceriodaphnia) P/F at 12%; February, May, August, November, See Part III, Condition N.
** See Part ffi, Condition O.. - AuA)uAl FY110tANT
�* ** Monthly average of 40 mg/l is permittted provided that the permittee can satisfactorily demonstrate that the difference between 20 mg/l
and 40 mg/l is due to the concentration of total suspended solids in the source body.
v(+) Or Similar Readings
,'The metal cleaning waste, coal pile runoff, ash transport water, low volume waste, and domestic wastewater shall be discharged into the ash
settling pond.
The pH shall not be less than 6.0 standard units nor greater than 9.0 standard units and shall be monitored weekly at the effluent by grab
sample.
vlMere shall be no discharge of floating solids or visible foam in other than trace amounts.

A. (). EFFLUENT LIMITATIONS AND MONITORING REQUIREMENTS FINAL Permit No. NCO004987
During the period beginning on the effective date of the permit and lasting until expiration, the Permittee is authorized to discharge from .
outfall(s) serial number 002, Ash settling pond. (Continued)
Effluent Cherecterlatic. Discharge 1_Imltatloni Monitoring Requirement!
Lbs/day Other Units .fsROclfv) Measurement $omnis *Samol•
Mon.Avg. Dally Max Mon, Avg. Dallg Max. Freguencv Tve• kqcatlon
Pollutant Analysis*** Annually E

A. (). EFFLUENT LIM[I TATIONS AND MONITORING REQUIREMENTS FINAL Permit No. NC0004997
During the period beginning on the effective date of the permit and lasting until expiration, the Permittee is authorized to discharge,from
outfall(s) serial number 003. Such discharges shall be limited and monitored by the permittee as specified below:
Effluent Characteristic. Discharge L.Imitatloni Monitoring Requirements
Lbs/day Units (speclfy Measurement Sa- male •Sam,�le
Mon. Avg. Dally Max Mon. Avg. Bally Max. Frequency Type Loca o
-11
Flow
Temperature
Total Residual Chlorine'
THERE SHALL BE NO CI-IROMMM, ZINC, OR COPPER ADDED TO THE TREATMENT SYSTEM EXCEPT AS PRE -APPROVED
ADDITIVES TO BIOCIDAL COMPOUNDS.
✓ ** The temperature of the effluent shall be such as not to cause an increase in the temperature of the receiving stream of -more than 2.8°C and in
no case cause the ambient water temperature to exceed 29°C.
***Monitoring requirements only apply if chlorine is added to the cooling water.
i The permittee shall obtain authorization from the Division of Environmental Management prior to utilizing any biocide in the cooling water (See
Part III of this Permit).
✓ The pH shall not be less than 6.0 standard units nor greater than 9.0 standard units.
r There shall be no discharge of floating solids or visible foam in other than trace amounts.

r' Part III Permit No. N00004987
E. There shall be no discharge of po]ychIorinated by
phenyl compounds such as those commonly
used for transformer fluid.
F. Biocide Condition
The permittee shall obtain authoriztion from the Division of Environmental Management prior to
utilizing any biocide in the cooling water. The permittee shall notify the Director in writing not
later than ninety (90) days prior to instituting use of any additional biocide used in cooling systems
which may be toxic to aquatic life other than those previously reported to the Division of
Environmental Management. 'Such notification shall include completion of Biocide Worksheet
Form 101 and a map locating the discharge point and receiving stream.
Concentrations of chromium, copper, or zinc added to biocides shall not exceed applicable water
quality standards or action levels in the receiving stream, as determined by calculations from the
biocide worksheet Form 101, with Supplemental Metals Analysis worksheet.
G. Continued intake screen backwash discharge is permitted without limitations or monitoring
requirements, except that there shall be no discharge of oil.
H. Nothing contained in this permit shall be constructed as awaiver by permittee or any right to a
hearing it may have pursuant to State or Federal laws or regulations.
I. The term "low volume waste sources" means, taken collectively as if from one source,
wastewater from all sources except those for which specific limitations are other wise established
in this part. Low volume wastes sources include, but are not limited to: Wastewater from wet
scrubber air pollution control .systems, ion exchange water treatment system water treatment
evaporator blowdown, laboratory and sampling streams, boiler blowdown,41oor drains, cooling
tower basin cleaning wastes, and recirculating house service water systems. Sanitary and air
conditioning wastes are not included
J. The term "metal cleaning waste" means any wastewater resulting from cleaning (with or without
chemical cleaning compounds) any metal process equipment including , but not limited to boiler
tube cleaning, boiler fireside cleaning, and air preheater cleaning. Metals cleaning will be
conducted according to Duke Power's approved equivalency demonstration.
K. The term " chemical metals cleaning waste" means any wastewater resulting from the cleaning
of any metal process equipment with chemical compounds, including, but not limited to, boiler
tube cleaning.
L. It has been determined from information submitted that the plans and procedures in place at
Marshall Steam Station are equivalent to that of a BMP.
M. If the permittee, after monitoring for at least six months, determines that he is consistently
meeting the effluent limits contained herein, the permittee may request of the Director that the
monitoring requirements be reduced to a -lesser frequency.

N. CHRONIC TOXICITY PASS/FAIL PERMIT LIMIT (QRTRLY)
The effluent discharge shall at no time exhibit chronic toxicity using test procedures outlined in:
1.) The North Carolina Ceriodaphnia chronic effluent bioassay procedure (North Carolina Chronic
Bioassay Procedure - Revised *September 1989) or subsequent versions.
The effluent concentration at which there may be no observable inhibition of reproduction or
significant mortality is 12% (defined as treatment two in the North Carolina procedure document).
The permit holder shall perform quarterly monitoring using this procedure to establish compliance
with the permit condition. The first test will be performed after thirty days from the effective date
of this permit during the months of February, May, August and November. Effluent sampling for
this testing shall be performed at the NPDES permitted final effluent discharge below all treatment
processes.
All toxicity testing results required as part of this permit condition will be entered on the Effluent
Discharge Monitoring Form (MR -1) for the month in which it was performed, using the parameter
code TGP3B. Additionally, DEM Form AT -1 (original) is to be sent to the following address:
Attention:
Environmental Sciences Branch
North Carolina Division of
Environmental Management
4401 Reedy Creek Road
Raleigh, N.C. 27607
Test data shall be complete and accurate andInclude all supporting chemical/physical measurements.
performed in association with the toxicity tests, as well as all dose/response data. Total residual
chlorine of the effluent toxicity sample must be measured and reported if chlorine is employed for
disinfection of the waste stream.
Should any single quarterly monitoring indicate a failure to meet specified limits, then monthly
monitoring will begin immediately until such time that a single test is passed. Upon passing, this
monthly test requirement will revert to quarterly in the months specified above.
Should any test data from this monitoring requirement or tests performed by the North Carolina
Division of Environmental Management indicate potential impacts to the receiving stream, this
permit may be re -opened and modified to include alternate monitoring requirements or limits.
NOTE: Failure to achieve test conditions as specified in the cited document, such as minimum
control organism survival and appropriate environmental controls, shall constitute an invalid test
and will require immediate retesting(within 30 days of initial monitoring event). Failure to submit
suitable test results will constitute noncompliance with monitoring requirements.
O. Pollutant Analysis Condition
The permittee shall conduct a test for pollutants annually at the effluent from the treatment plant.
The discharge shall be evaluated as follows: 1) A pollutant analysis of the effluent must be
completed annually. using EPA approved methods for the following analytic fractions: (a)
purgeables (i.e., volatile organic compounds); (b) acid extractables; (c) base/neutral extractables;
(d) organochlorine pesticides and PCB's (e) herbicides; and (f) metals and other inorganics. The
Annual Pollutant Analysis Monitoring (APAM) Requirement Reporting Form A and accompanying
memo, to be provided to all discharges affected by this monitoring requirement, describes the
sampling and analysis requirements and lists chemicals, to be included in the pollutant analysis.
This monitoring requirement is to be referred'to as the "Annual Pollutant Analysis Monitoring
Requirement" (APAM).
(2) Other significant levels of organic chemicals must be identified and approximately quantified.
For the purpose of implementing this requirement, the largest 10 GC/MS peaks in the purgeable

3 a base/neutral extractable, and ' acid extractable .fractions (or fewer than 10, if less than 10
unidentified peaks occur) for chemicals other than those specified on the ADAM Requirement
Reporting Form A should be identified and approximately quantified as stated in the APAM
Reporting Form A instructions. This part (item 2) of the APAM requirement is to be referred to as
the "10 significant peaks rule".
P. Discharge of any product registered under the Fedral Insecticide, Fungicide, .and Rodenticide
Act to any wastestream which may ultimately be released to lakes, rivers,streams, or other waters
of the United States is prohibited unless specifically authorized elsewere in this permit. Discharge
of chlorine from the use of chlorine gas, sodium hypochlorite, or other similar chlorination
compounds for disinfection in plant potable and service water systems and in sewage treatment is
authorized. Use of restricted use pesticides for lake management purposed by applicators licensed
by the N. C. Pesticide Board is allowed.
Q. It has been demonstrated that under certain conditions it is possible to reduce the concentration
of metals in boiler cleaning wastes in the range of 92 to 99+ percent by treatment in ash ponds.
Because of dilution problems, and the existence of boundary interface layers at the extremities of
the plume, it is difficult to prove beyond doubt that the quantity of iron and copper discharged will
always be less than one milligram per liter times the flow of metal cleaning wastes when treated in
this manner.
The application of physical/chemical methods of treating wastes has also been demonstrated to be
effective in the treatment of metal cleaning wastes. However, the effectiveness of ash pond
treatment should be considered in relation to the small differences in effluent quality realized
between the two methods.
It has been demonstrated that the presence of ions of copper, iron, nickel, and zinc in the ash pond
waters was not measurably increased during the ash pond equivalency demonstration at the Duke
Power Company's Riverbend . Steam Station. -Therefore, when the following conditions are
implemented during metal cleaning procedures, effective treatment for metals can be obtained at
this facility:
1. Large ash basin providing potential reaction volumes in the ratio of 100 to 1.
2. Well-defined shallow ash delta near the ash basin influent.
3. Ash pond pH of no less than 6.5 prior to metal cleaning waste addition.
4. Four days retention time in ash pond with effluent flow virtually stopped.
5. Boiler volume'less than 86,000 gallons.
6. - Chemicals for cleaning to include only one or more of the following:
a. Copper removal step -sodium bromate, NaBrO; ammonium carbonate, (NH)CO; and
ammonium hydroxide, NHOH.
b. Iron removal step -hydrochloric acid, HCl; and ammonium bifluoride, (NH)BF, copper
complexer, citric acid and proprietory inhibitors.
c. Neutralization step, soda ash and trisodium phosphate.
7. Maximum dilution of wastes before entering ash pond 6 to 1.
8. After treatment of metal cleaning wastes; if monitoring of basin effluents as required by
the permit reveals discharges outside the limits of the permit, permittee will re=close the basin
discharge, conduct such in -basin sampling necessary to determine the cause of nonconformance,
will take appropriate corrective actions, and will file a report with EPA including all pertinent data
R. Beginning on the effective date of this permit and lasting until expiration, there shall be no
discharge of plant wastes to the ash pond unless the permittee provides and maintains at all times a

mimmum tree water volume (between the top of the sediment level and the minimum discharge
elevation) equivalent to the sum of the maximum 24-hour plant discharges plus all direct rainfall' `
and all runoff flows to the pond resulting from a 10 -year, 24-hour rainfall event, when using a
runoff coefficient of 1.0. During the term of the permit, the permittee shall remove settled material y
from the ponds or otherwise enlarge the available storage capacities in order to maintain the
required minimum volumes at all times. No later than December 31, 1990 and annually thereafter,
the permittee shall determine and report to the permit issuing authority: (1) the actual free water
volume of the ash pond, (2) physical measurements of the dimensions of Labe free water volume in
sufficient detail to allow validation of the calculated volume, and (3) a certification that the required
volume is available with adequate safety factor to include all solids expected to be deposited in the
ponds for the following year. Present information indicates a needed volume of 723.7 A -ft in
addition to solids which will be deposited in the ash pond. Any changes to plant operations
affecting such certification shall be reported to the Director within five days.
NOTE: In the event that adequate volume has been certified to exist for the term of the permit,
periodic certification is not needed
S. The permittee shall report all visible discharges of floating materials, such as, an oil sheen to
the Director when submitting DMR's.