North Lake PP-CS030829Office
Memorandum
TXU
TXU Environmental Services
Date: August 12, 2003
To: Damon Crowther
From: Scott Wilde
cc: See Below
Re: North Lake Steam Electric Station
TCEQ Waste Water Discharge Permit No. 01249
Draft Permit
The Texas Commission on Environmental Quality has issued a final draft Permit and a public
notice to have published in the newspaper of greatest circulation in the county in which the
facility resides. The final draft Permit must be in a public location for public review along with
the application, the Executive Director's Preliminary Decision and the Fact Sheet. All but the
application are included in this enclosure. Please deliver this document [o:
William T. Cozby Public Library
177 North Heartz Road
Coppell, Texas
Be sure they are aware that these documents must stay on display until you receive the final
permit. Please get a copy of the stamped cover showing documentation that you have taken it to
the library. If they don't stamp the documents, please just drop me a note telling me when you
took them to the library.
If you have any questions, Please feel free to contact me at 214-812-5221.
Attachment
cc: Jerry Crawford (w/o Attachment)
Robert Thompson (w/o Attachments)
~Izq~°~
TEXAS COMMISSION ON ENVIItONMENTAL QUALITY
P. O. Box 13087
Austin, Texas 78711-3087
PERMIT TO DISPOSE OF WASTES
under provisions of
Section 402 of the Clean Water Act
and Chapter 26 of the Texas Water Code
TXU Generation Company LP
whose mailing address is
Water Permitting Coordinator
Environmental Services
Energy Plaza, 1601 Bryan Street
Dallas, Texas 75201-3411
TPDES PERMff N0.01249
For TCEQ office use only -
EPAI.D. No. TX00302951
This is a renewal of TPDES Permit No.
01249, issued on October 5, 1999.
is authori2ed to treat and dispose of wastes from the North Lake Steam Electric Station (SIC 4911)
located at 14901 North Lake Road, on the north shore of North Lake immediately southeast of the Moore Road and
Belt Line Road intersection, approximately one mile east of the City of Cappell, Dallas County, Texas
from Outfa11001 via the Once-through Cooling Discharge Canal to North Lake; thence either via the blowdown-
receiving structure to the Elm Fork Trinity River below Lewisville Lake in Segment No. 0822 ofthe Trinity River
Basin or via the reservoir spillway to the South Fork of Grapevine Creek ;thence to Grapevine Creek; thence to
the Elm Fork Trinity River below Lewisville Lake in Segment No. 0822 of the Trinity River Basin; and
from Outfa11002 to the South Fork of Grapevine Creek; thence to Grapevine Creek; thence to the Elm Fork Trinity
River below Lewisville Lake in Segment No. 0822 of the Trinity River Basin and/or to Grapevine Creek; thence
to the Elm Fork Trinity River Below Lake Lewisville in Segment No. 0822 of the Trinity River Basin
only according to effluent limitations, monitoring requirements and other conditions set forth in this permit, as well
as the rules of the Texas Commission on Environmental Quality (TCEQ), the laws of the State of Texas, and other
orders of the TCEQ. The issuance of this permit does not grant to the pernrittee the right to use private or public
property for conveyance of wastewater along the discharge route described in this permit. This includes, but is not
limited to, property belonging to any individual, partnership, corporation or other entity. Neither does this permit
authorize any invasion of personal rights nor any violation of federal, state, or local laws or regulations. It is the
responsibility of the percnittee to acquire property rights as may be necessary to use the discharge route.
This permit shall expire at midnight on October 1, 2006.
ISSUED DATE:
For the Commission
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DEFINITIONS AND STANDARD PERMIT CONDITIONS
TPDES Permit No. 01249
As required by Title 30 Texas Administrative Code (TAC) Chapter 305, certain regulations appeaz as standazd conditions in
waste discharge permits. 30 TAC §§ 305.121 - 305.129 (relating to Permit Characteristics and Conditions) as promulgated
under the Texas Water Code §§ 5.103 and 5.105, and the Texas Health and Safety Code §§ 36].017 and 361.0240, establish
the characteristicsand standards for waste dischazge permits, including sewage sludge, and those sections of 40 Code of Federal
Regulations (CFR) Part 122 adopted by reference by the Commission. The following text includes these conditions and
incorporates them into this permit. All defmitions in Section 26.001 of the Texas Water Code aad 30 TAC Chapter 305 shall
apply to this permit and are incorporated by reference. Some specific defmitions of words or phrases used in this permit aze
as follows:
1. Flow Measurements
a. Annualaverageflow-the arithmetic averageofalldailyflowdetemtinationstakenwithintheprecedingl2consecutive
calendar months. The awual average flow determination shall consist of daily flow volume determinations made by
a totalizing meter, charted on a chart recorder aad limited to major domestic wastewater dischazge facilities with a 1
million gallons per day or greater permitted flow.
b. Daily average flow -the arithmetic average of all determinations of the daily flow within a period of one calendaz
month. The daily average flow determination shall consist of determinations made on at least four sepazate days. If
instantaneous measurements aze used to detemrine the daily flow, the detemtination shall be the arithmetic average of
all instantaneous measurements taken during that month. Daily average flow determination for intemtittent dischazges
shall consist of a minimum of three flow determinations on days of discharge.
c. Daily maximum flow -the highest total flow for any 24-hour period in a calendaz month.
d. Instantaneous flow -the measured flow during the minimum time required to interpret the flow measuring device.
e. 2-hour peak flow (domestic wastewater treatment plants) -the maximum flow sustained for atwo-hour period during
the period of daily discharge. The average of multiple measurements of instantaneous maximum flow within a two-
hour period may be used to calculate the 2-hour peak flow.
f. Maximum 2-hour peak flow (domestic wastewater treatment plants) -the highest 2-hour peak flow for any 24-hour
period in a calender month.
2. Concentration Measurements
a. Daily average concentration -the arithmetic average of all effluent samples, composite or grab as required by this
permit, within a period of one calendar month, consisting of at least four separate representative measurements.
i. For domestic wastewater treatment plants -When four samples are not available in a calendar month, the
arithmetic average (weighted by flow) of all values in the previous four consecutive month period consisting of
at least four measurements shall be utilized as the daily average concentration.
ii. For all other wastewater treatment plants -When four samples are not available in a calender month, the arithmetic
average (weighted by flow) of all values taken during the month shall be utilized as Ute daily average
concentration.
b. 7-day average concentration - [he arithmetic average of all effluent samples, composite of grab as required by this
permit, within a period of one calendar week, Sunday through Saturday.
c. Daily maximum concentration -the maximum concentration measured on a single day, by the sample type specified
in the permit, within a period of one calender month.
d. Daily dischazge - Ute dischazge of a pollutant measured during a calendar day or any 24-hour period that reasonably
represents the calendar day for purposes of sampling. For pollutants with limitations expressed in terms of mass, the
daily discharge" is calculated as the total mass of the pollutant dischazged over the sampling day. For pollutants with
limitations expressed in other units of measurement, the "daily dischazge" is calculated as the average measurement
of the pollutant over the sampling day.
The "daily discharge" determination ofconcentration made using a composite sample shall be the concentration of the
composite sample. When grab samples are used, the "daily discharge" determination of concentration shall be the
Page 3
TXU Generation Company LP TPDES Permit No. 01249
arithmetic average (weighted by flow value) of all samples collected during that day
e. Fecal coliform bacteria concentration -the number of colonies of fecal coliform bacteria per 100 milliliters effluent.
The daily average fecal colifomt bacteria concentration is a geometric mean of the values for the effluent samples
collected in a calendaz month. The geometric mean shall be determined by calculating the nth root of the product of
all measurements made in a calender month, where n equals the number of measurements made; or, computed as the
antilogarithm of the arithmetic mean of the logarithms of all measurements made in a calender month. For any
measurement of fecal coliform bacteria equaling zero, a substituted value of one shall be made for input into either
computation method. The 7-day average for fecal coliform bacteria is the geometric mean of the values for all effluent
samples collected during a calender week.
£ Daily average loading (]bs/day) -the azithmetic average of all daily discharge loading calculations during a period of
one calender month. These calculations must be trade for each day of the month that a parameter is analyzed. The
daily dischazge, in terms of mass (lbs/day), is calculated as (Flow, MGD x Concentration, mg/I x 8.34).
g. Daily maximum loading (]bs/day) -the highest daily discharge, in terms of mass (]bs/day), within a period of one
calender month.
3. Sample Type
a. Composite sample -For domestic wastewater, a composite sample is a sample made up of a minimum of three effluent
portions collected in a continuous 24-hour period or during the period of daily discharge if less than 24 hours, and
combined in volumes proportional to flow, and collected at the intervals required by 30 TAC § 319.9 (a). For industrial
wastewater, a composite sample is a sample made up of a minimtun of three effluent portions collected in a continuous
24-hour period or during the period of daily discharge if less than 24 hours, and combined in volumes proportional to
flow, and collected at the intervals required by 30 TAC § 319.9 (b).
b. Grab sample - an individual sample collected in less than 15 minutes.
4. Treatment Facility(facility)-wastewater facilities usedintheconveyance,storage,treatment, recycling, reclamationand/or
disposal of domestic sewage, industrial wastes, agricultural wastes, recreational wastes, or other wastes including sludge
handling or disposal facilities under the jurisdiction of the Commission.
5. The term "sewage sludge" is defined as solid, semi-solid, or liquid residue generated during the treatment of domestic
sewage in 30 TAC Chapter 312. This includes the solids which have not been classified as hazazdous waste sepazated from
wastewater by unit processes .
6. Bypass -the intentional diversion of a waste stream from any portion of a treatment facility.
MONITORING AND REPORTING REQUIREMENTS
1. Self-Reporting
Monitoring results shall be provided at the intervals specified in the permit. Unless otherwise specified in this pertttit or
otherwise ordered by the Conunission, the peratittee shall conduct effluent sampling and reporting in accordance with 30
TAC §§ 319.4 - 319.12. Unless otherwise specified, a monthly effluent report shall be submitted each month, to the
Enforcement Division (MC 224), by the 20th day of the following month for each dischazge which is described by this
permit whether or not a dischazge is made for that month. Monitoring results must be reported on an approved self-report
fomt, that is signed and certified as required by Monitoring and Reporting Requirements No. 10.
As provided by state law, the pemtittee is subject to administrative, civil and criminal penalties, as applicable, for
negligently or lmowingly violating the Clean Water Act, the Texas Water Code, Chapters 26, 27, and 28, and Texas Health
and Safety Code, Chapter 361, including but not limited to ]mowingly making any false statement, representation, or
certification on any report, record, ar other document submitted or required to be maintained under this perndt, including
monitoring reports or reports of compliance or noncompliance, or falsifying, tampering with or knowingly rendering
inaccurate any monitoring device or method required by this permit or violating any other requirement imposed by state
or federal regulations.
2. Test Procedures
Unless otherwise specified in this permit, test procedures for the analysis of pollutants shall comply with procedures
Page 4
TXU Generation Company LP
TPDES Permit No. 01249
specified in 30 TAC §§319.11 - 319.]2. Measurements, tesu and calculations shall be accurately accomplished in a
representative manner.
3. Records of Results
a. Monitoring samples and measurements shall be taken at times and in a manner so as to be representative of the
monitored activity.
b. Except for records of monitoring infomtation required by this pemtit related to the pemtittee's sewage sludge use and
disposal activities, which shall be retained for a period of at least five years (or longer as required by 40 CFR Part 503),
monitoring and reporting records, including strip charts and records of calibration and maintenance, copies of all
records required by this permit records of all data used to complete the application for this pemti; and the certification
required by 40 CFR § 264.73(b)(9) shall be retained at the facility site, or shall be readily available for review by a
TCEQ representative for a period ofthree years fromthe date ofthe record or sample, measurement report, application
or certification. This period shall be extended at the request of the Executive Director.
c. Records of monitoring activities shall include the following
i. date, time and place of sample or measurement;
ii. identity of individual who collected the sample or made the measurement.
iii. date and time of analysis;
iv. identity of the individual and laboratory who performed the analysis;
v, the technique or method of analysis; and
vi. the results of the analysis or measurement and quality assurance/quality control records.
The period during which records are required to be kept shall be automatically extended to the date of the final
disposition of any administrative or judicial enforcement action that maybe instituted against the permittee.
4. Additional Monitoring by Pemtittee
If the permittee monitors any pollutant at the location(s) designated herein more frequently than required by this permit
using approved analytical methods as specified above, all results of such monitoring shall be included in the calculation
and reporting of the values submitted on the approved self-report form Increased frequency of sampling shall be indicated
an the self-report form
5. Calibration of Instruments
All automatic flow measuring or recording devices and all totalizing meters for measuring flows shall be accurately
calibrated by a trained person at plant start-up and as often thereafter as necessary to ensure accuracy, but not less often than
annually unless authorized by the Executive Director for a longer period. Such person shall verify in writing that the device
is operating properly and giving accurate results. Copies of the verification shall be retained at the facility site and/or shall
be readily available for review by a TCEQ representative for a period of three years.
6. Compliance Schedule Reports
Reports of compliance or noncompliance with, or any progress reports on, interim and fatal requirements contained in any
compliance schedule of the permit shall be submitted no later than 14 days following each schedule date to the Regional
Office and the Enforcement Division (MC 224).
7. Noncompliance Notification
a. In accordance with 30 TAC § 305.125(9) any noncompliance which may endanger human health or safety, or the
environment shall be reported by the permittee to the TCEQ. Report of such information shall be provided orally or
by facsimile transmission (FAX) to the Regional Office within 24 hours of becoming aware of the noncompliance.
A written submission of such information shall also be provided by the pemilttee to the Regional Oflice and the
Enforcement Division (MC 224) within five working days of becoming aware of the noncompliance. The written
submission shall contain a description of the noncompliance and its cause; the potential danger to human health or
safety, or the environment; the period of noncompliance, including exact dates and times; if the noncompliance has
not been corrected, the time it is expected to continue; and steps taken or planned to reduce, eliminate, and prevent
recurrence of the noncompliance, and to mitigate its adverse effects.
b. The following violations shall be reported under Monitoring and Reporting Requirement 7.a
Page 5
TXU Generation Company LP TPDES Permit No. 01249
i. Unauthorized dischazges as defined in Pemrit Condifion 2(g).
ii. Any unanticipated bypass which exceeds any effluent limitation in the pemvt.
iii. Violatton of a permitted maximum daily dischazge limitation for pollutants listed specifically in the Other
Requirements section of an Industrial TPDES permit.
c. In addition to the above, any effluent violation which deviates from the permitted effluent limitation by more than 40%
shall be reported by the permittee in writing to the Regional Office and Ute Enforcement Division (MC 224) within 5
working days of becoming aware of the noncompliance.
d. Any noncompliance other than that specified in this section, or any required information not submitted or submitted
incorrectly, shall be reported to the Enforcement Division (MC 224) as promptly as possible. For effluent limitation
violations, noncompliances shall be reported on the approved self-report form
8. In accordance with the procedures described is 30 TAC §§ 35.301 - 35.303 (relating to Water Quality Emergency and
Temporary Orders) if the permittee knows in advance of the need for a bypass, it shall submit prior notice by applying for
such authorization.
9. Changes in Dischazges of Toxic Substances
All existing manufacturing, commercial, mining, and silvicultural pertnittees shall notify the Regional Office, orally or by
facsimile transmission within 24 hours, and both the Regional Office and the Enforcement Division (MC 224) in writing
within five (5) working days, after becoming aware of or having reason to believe:
a. That any activity has occurred or will occur which would result in the discharge, on a routine or frequent basis, of any
toxic pollutant listed at 40 CFR Part 122, Appendix D, Tables R and III (excluding Total Phenols) which is not limited
in the permit, if that discharge will exceed the highest of the following "notification levels":
i. One hundred microgams per liter (]00 µg2);
ii. Two hundred micrograms per liter (200 µg2) for acrolein and acrylonitrile; five hundred micrograms per liter
(500 µg2) for 2,4-dinitraphenol and for 2-methyl-0,Crdinitrophenol; and one milligram per liter (1 mgt) for
antimony;
iii. Five (5) times the maximum concentration value reported for that pollutant in the pemrit application; or
iv. The level established by the TCEQ.
b. That any activity has occurred or will occur which would result in any dischazge, on a nomoutine or infrequent basis,
of a toxic pollutant which is not limited in the permit, if that discharge will exceed the highest of the following
"notification levels":
i. Five hundred micrograms per liter (500 µg2);
ii. One milligram per liter (1 mg/L) for antunony;
iii. Ten (10) times the maximum concentration value reported for that pollutant in the permit application; or
iv. The level established by the TCEQ.
10. Signatories to Reports
All reports and other information requested by the Executive Duector shall be signed by the person and in the manner
required by 30 TAC § 305.128 (relating to Signatories to Reports).
11. All Publicly Owned Treatment Works (POTWs) must provide adequate notice to the Executive Duector of the following:
a. Any new introduction of pollutants into the POTW from an indirect discharger which would be subject to section 301
or 306 of the CWA if it were dvectly discharging those pollutants;
b. Any substantial change in the volume or character of pollutants being introduced into that POTW by a source
introducing pollutants into the POTW at the time of issuance of the permit; and
c. For the purpose of this paragraph, adequate notice shall include information on:
i. The quality and quantity of effluent introduced into the POTW; and
ii. Any anticipated impact of the change on the quantity or quality of ettluent to be discharged from the POTW.
Page 6
TXU Generation Company LP
PERMIT CONDITIONS
1. General
TPDES Permit No. 01249
a. When the perinittee becomes awaze that it failed to submit any relevant facts in a pemrit application, oi• submitted
incorrect infamtation in an application or in any report to the Executive Duector, it shall promptly submit such facts
or information.
b. This pemilt is granted on the basis of the information supplied and representations made by the pemtittee during action
on an application, and relying upon the accuracy and completeness ofthat information and those representations. After
aotlce and opportunity for a hearing, this permit may be modified, suspended, or revoked, in whole or in part, in
accordance with 30 TAC Chapter 305, Subchapter D, during its term for good cause including, but not limited to, the
following:
i. Violation of any terms or conditions of this pemrit;
ii. Obtaining this permit by misrepresentation or failure to disclose fully all relevant facts; or
iii. Achangeinanyconditionthatrequireseitheratemporaryorpermanentteductionoreliminationoftheauthorized
dischazge.
c. The permittee shall furnish to the Executive Duector, upon request and within a reasonable time, any infomration to
determine whether cause exists for amending, revoking, suspending or terminating the permit. The permittee shall also
famish to the Executive Duector, upon request, copies of records required to be kept by the permit.
2. Compliance
a. Acceptance of the pemtit by the person to whom it is issued constitutes aclmawledgment and agreement that such
person will comply with all the terms and conditions embodied in the permit, and the rules and other orders of the
Commission.
b. The permittee has a duty to comply with all conditions of the pemtit. Failure to comply with any permit condition
constitutes a violation of the permit and the Texas Water Code or the Texas Health and Safety Code, and is grounds
for enforcement action, for permit amendment, revocation or suspension, or for denial of a permit renewal application
or an application for a permit for another facility.
c. It shall not be a defense for a pemrittee in an enforcement actlon that it would have been necessary to halt or reduce
the pemvtted activity in order to maintain compliance with the conditions of the permit.
d. The pemuttee shall take all reasonable steps to min;mi~e or prevent any discharge or sludge use or disposal or other
pemtit violation which has a reasonable likelihood of adversely affecting human health or the environment.
e. Authorization from the Commission is required before beginning any change in the pemritted facility or activity that
may result in noncompliance with any permit requirements.
f. A permit maybe amended, suspended and reissued, or revoked for cause in accordance with 30 TAC §§ 305.62 and
305.66 and Texas Water Code Section 7.302. The filing of a request by the permittee for a pemrit amendment,
suspension and reissuance, or temunation, or a notification ofplanned changes or anticipated noncompliance, does not
stay any permit condition.
g. There shall be no unauthorized dischazge of wastewater or any other waste. For the purpose of this permit, an
unauthorized discharge is considered to be any discharge of wastewater into or adjacent to water in the state at any
location not permitted as an outfall or otherwise defined in the Other Requirements secrion of th;s permit.
h. In accordance with 30 TAC § 305.535(a), the pemrittee may allow any bypass to occur from a TPDES pemritted
facility which does not cause pemtitted ellluent limitations to be exceeded or an unauthorized discharge to occur, but
only if the bypass is also for essential maintenance to assure efficient operation.
i. Thepermitteeissubjecttoadministtative,civil,andcriminalpenalties, as applicable, under Texas Water Code§§7.051
- 7.075 (relating to Administrative Penalties), 7.101 - 7.111 (relating to Civil Penalties), and 7.141 - 7.202 (relating
to Criminal Offenses and Penalties) for violations including, but not limited to, negligently or knowingly violating the
federal Clean Water Act, §§ 301, 302, 306, 307, 308, 318, or 405, or any condition or limitation implementing any
sections in a permit issued under the CWA § 402, or any requirement imposed in a pretreatment program approved
under the CWA §§ 402 (a)(3) or 402 (b)(8).
Page 7
TXU Generation Company LP
3. Inspections aad Entry
TPDES Permit No. 01249
a. Inspection and entry shall be allowed as prescribed in the Texas Water Code Chapters 26, 27, and 28, and Texas Health
and Safety Code Chapter 361.
b. The members of the Commission and employees and agents of the Commission are entitled to enter any public or
private property at any reasonable time for the purpose of inspecting and investigating conditions relating to the quality
of water in the state or the compliance with any rule, regulation, pemdt or other order of the Commission. Members,
employees, or agents of the Commission and Commission contractors aze entitled to enter public or private property
at any reasonable time to investigate or monitor or, if the responsible party is not responsive or there is an immediate
danger to public health or the environment, to remove or remediate a condition related to the quality of water in the
state. Members, employees, Commission contractors, or agents acting under this authority who enter private property
shall observe the establishment's rnles and regulatons concerning safety, internal security, and fue protection, and if
the property has management in residence, shall notify management or the person then in charge of his presence and
shall exhibit proper credentials. If any member, employee, Commission contractor, or agent is refused the right to
enter in or on public or private property under this authority, the Executive Duector may invoke the remedies
authorized in Texas Water Code Section 7.002. The statement above, that Commission entry shall occur in accordance
with an establishment's rules and regulations concerning safety, internal security, and fire protection, is not grounds
for denial or restriction of entry to any part of the facility, but merely describes the Commission's duty to observe
appropriate rules and regulations during an inspection.
4. Permit Amendment and/or Renewal
a. The permittee shall give notice to the Executive Director as soon as possible of any planned physical alterations or
additions to the permitted facility if such alterafions or additions would require a permit amendment or result in a
violation of permit requirements. Notice shall also be required under this paragraph when:
i. The alteration or addition to a permitted facility may meet one of the criteria for deternuning wheffier a facility
is a new source in accordance with 30 TAC § 305.534 (relating to New Sources and New Dischargers); or
ii. The alteration or addition could significantly change the nature or increase the quantity of pollutants discharged.
This notification applies to pollutants which are subject neither to effluent limitations in the permit, nor to
notification requirements in Monitoring and Reporting Requirements No. 9;
iii. The alteration or addition results in a significant change in the permittee's sludge use or disposal practices, and
such alteration, addition, or change may justify the applicaton of permit conditions that are different from or
absent in the existing permit, including notification of additional use or disposal sites not reported during the
permit application process or not reported pursuant to an approved land application plan.
b. Prior to any facility modifications, additions, or expansions that will increase the plant capacity beyond the permitted
flow, the permittee must apply for and obtain proper authorization from the Commission before commencing
construction.
c. The permittee must apply for an amendment or renewal prior to expiration of the existing perrnit in order to continue
a permitted activity after the expiration date of the perndt. If an application is submitted prior to the expiration date
of the perrrrit, the existing permit shall remain in effect until the application is approved, denied, or returned. If the
application is returned or denied, authorization to continue such activity shall terminate upon the effective date ofthe
action. If an application is not submitted prior to the expiration date of the pemtit, the permit shall expire and
authorization to continue such activity shall terminate.
d. Prior to accepting or generating wastes which aze not described in the permit application or which would result in a
significant change in the quantity or quality of the existing dischazge, the permittee must report the proposed changes
to the Commission. The permittee must apply for a permit amendment reflecting any necessary changes in pemrit
conditions, including effluent limitations for pollutants not identified and limited by this pemdt.
e. In accordance with the Texas Water Code § 26.029(b), after a public hearing, notice of which shall be given to the
pemdttee, the Cormtussioa may require the pemittee, from time to time, for good cause, in accordance with applicable
laws, to conform to new or additional conditons.
f. If any toxic effluent standard or prohibition (including any schedule of compliance specified in such effluent standazd
or prohtbition) is promulgated under Section 307(a) of the Clean Water Act for a toxic pollutant which is present in
the discharge and that standard or prohibition is more stringent than any limitation on the pollutant in this permit, this
Page 8
TXU Generation Company LP
TPDES Permit No. 01249
permit shall be modified or revoked and reissued to conform to the toxic effluent standard or prolu'bition. The pemilttee
shall comply with effluent standazds or prohibitions established under Section 307(a) of the Clean Water Act for toxic
pollutants within the time provided in the regulations that established those standards or prohibitions, even ifthe pernilt
has not yet been modified to incorporate the requirement.
5. Permit Transfer
a. Prior to any transfer of this perrrtit, Commission approval must be obtained. The Commission shall be notified in
writing of any change in control or ownership of facilities authorized by this pemdt. Such notification should be sent
to the Water Quality Applications Team (MC 161) of the Registration, Review, and Reporting Division.
b. A permit may be transferred only according to the provisions of 30 TAC § 305.64 (relating to Transfer of Pemrits) and
30 TAC § 50.133 (relating to Executive Director Action on Application or WQMP update).
6. Relationship to Hazardous Waste Activities
This permit does not authorize any activity of hazardous waste storage, processing, or disposal which requires a perailt or
other authorization pursuant to the Texas Health and Safety Code.
7. Relationship to Water Rights
Disposal of treated effluent by any means other than dischazge directly to water in the state must be specifically authorized
in this pemilt and may requue a permit pursuant to Chapter 11 of the Texas Water Code.
8. Property Rights
A permit does not convey any property rights of any sort, or any exclusive privilege.
9. Permit Enforceability
The conditions of this permit aze severable, and if any provision of this permit, or the application of any provision of this
permit to any circumstances, is held invalid, the application of such provision to other circumstances, and the remainder
of this permit, shall not be affected thereby.
OPERATIONAL REQUIREMENTS
1. The permittee shall at all times ensure that the facility and all of its systems of collection, treatrnent, and disposal are
properly operated and maintained. This includes, but is not limited to, the regulaz, periodic examination of wastewater
solids within the treatment plant by the operator in order to maintain an appropriate quantity and quality of solids inventory
as described in the various operator training manuals and according to accepted industry standazds for process control.
Process control, maintenance, and operations records shall be retained at the facility site, or shall be readily available for
review by a TCEQ representative, for a period of three yeazs.
2. Upon request by the Executive Director, the pemdttee shall take appropriate samples and provide proper analysis in order
to demonstrate compliance with Commission rules. Unless otherwise specified in this permit or otherwise ordered by the
Commissioq the permittee shall comply will[ all applicable provisions of30 TAC Chapter 312 concerning sewage sludge
use and disposal and 30 TAC §§ 319.21 - 319.29 concerning the discharge of certain hazardous metals.
3. Domestic wastewater treatment facilities shall comply with the following provisions:
a. The pemilttee shall notify the Municipal Permits Team, Wastewater Permitting Section (MC 148) of the Water Quality
Division, in writing, of any facility expansion at least 90 days prior to conducting such activity.
b. The pemtittee shall submit a closure plan for review and approval to the Agriculhlre and Sludge Team, Wastewater
Permitting Section (MC 148) ofthe Water Quality Division, for any closure activity at least 90 days prior to conducting
such activity. Closure is the act ofpemranently taking a waste management unit or treatment facility out of service and
includes dre permanent removal from service of any pit, tank, pond, lagoon, surface impoundment and/or other
treatment unit regulated by this perntit.
4. 'The permittee is responsible for installing prior to plant start-up, and subsequently maintaining, adequate safeguards to
prevent the dischazge of untreated or inadequately treated wastes during electrical power failures by means of alternate
power sources, standby generators, and/or retention of inadequately treated wastewater.
Page 9
TXU Generation Company LP
TPDES Permit No. 01249
5. Unlessotherwisespecified,thepermitteeshallprovideareadilyaccessiblesamplingpointand,whereapplicable,aneffluent
flow measuring device or other acceptable means by which effluent flow may be determined.
6. The pemittee shall remit an annual water quality fee to the Commission as requved by 30 TAC Chapter 21. Failure to pay
the fee may result in revocation of this permit under Texas Water Code § 7.302(b)(ti).
7. Documentation
For all written notifications to the Commission required of the pemilttee by this permit, the permittee shall keep and make
available a copy of each such notification under the same conditions as self-monitoring data are required to be kept and
made available. Except for information required for TPDES pemtit applications, effluent data, including effluent data in
permits, draft permits and permit applications, and other information specified as not confidential in 30 TAC § 1.5(d), any
information submitted pursuant to this pemrit maybe claimed as confidential by the submitter. Any such claim must be
asserted in the manner prescribed in the applicafion form or by stamping the words "confidential business information" on
each page containing such information. If no claim is made at the time of submission, information maybe made available
to the public without further notice. If the Commission or Executive Duector agrees with the designation of co~den6ality,
the TCEQ will not provide the information for public inspection unless required by the Texas Attorney General or a court
pursuant to an open records request. If the Executive Duector does not agree with the designation of confidentiality, the
person submitting the information will be notified.
8. Facilities which generate domestic wastewater shall comply with the following provisions; domestic wastewater treatment
facilities at permitted industrial sites are excluded.
a. Whenever flow measurements for any domestic sewage treatment facility reach 75 percent of the permitted daily
average or annual average flow for three consecutive months, the permittee must initiate engineering and fmancial
planning for expansion and/or upgrading of the domestic wastewater treatment and/or collection facilities. Whenever
the flow reaches 90 percent of the permitted daily average or annual average flow for three consecutive months, the
pemvttee shall obtain necessary authorization from the Commission to commence constmction of the necessary
additional treatment and/or collection facilities. In the case of a domestic wastewater treatment facility which reaches
75 percent of the pemvtted daily average or annual average flow for three consecutive months, and the planned
population to be served or the quantity of waste produced is not expected to exceed the design limitations of the
treatment facility, the permittee shall submit an engineering report supporting this claim to the Executive Dtrector of
the Commission.
If in the judgement of the Executive Duector the population to be served will not cause permit noncompliance, then
the requirement of this section may be waived. To be effective, any waiver must be in writing and signed by the
Drector of the Enforcement Division (MC 149) of the Commission, and such waiver of these requirements will be
reviewed upon expiration of the existing pemuh however, any such waiver shall not be interpreted as condoning or
excusing any violation of any permit parameter.
b. The plans and specifications for domestic sewage collection and treatment works associated with any domestic permit
must be approved by the Commission, and failure to secure approval before commencing construction of such works
or making a discharge is a violation of this permit and each day is an additional violation until approval has been
secured.
c. Pemtits for domestic wastewater treatment plants are granted subject to the policy of the Commission to encourage the
development of azea-wide waste collection, treatment and disposal systems. The Commission reserves the right to
amend any domestic wastewater pemtit in accordance with applicable procedural requirements to require the system
covered by this permit to be integrated into an area-wide system, should such be developed; to require the delivery of
' the wastes authorized to be collected in, treated by or discharged from said system, to such area-wide system; or to
amend this pernut in any other particular to effectuate the Commission's policy. Such amendments may be made when
the changes required are advisable for water quality control purposes and are feasible on the basis of waste treatment
technology, engineering, fmancial, and related considerations existing at the time the changes are required, exclusive
of the loss of investment in or revenues from any then existing or proposed waste collection, treatment or disposal
system
9. Domestic wastewater treatmentplantsshallbeoperatedandmaintainedbysewageplantoperatorsholdingavalidcertificate
of competency at the required level as defined in 30 TAC Chapter 30.
] 0. For Publicly Owned Treatment Works (POTWs), the 30-day average (or monthly average) percent removal for BOD and
TSS shall not be less than 85 percent, unless otherwise authorized by this pemrit.
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TXCJ Generation Company LP
TPDES Permit No. 01249
11. Facilities which generate industrial solid waste as defined in 30 TAC § 335.1 shall comply with these provisions:
a. Any solid waste, as defined in 30 TAC § 335.1 (including butnotlimited tosuch wastes as gazbage, refuse, sludge from
a waste treatment, water supply treatment plant or air pollution control facility, discarded materials, discazded materials
to be recycled; whether the waste is solid, liquid, or semisolid), generated by the pemrittee during the management and
treatment of wastewater, must be managed in accordance with all applicable provisions of 30 TAC Chapter 335,
relating to Industrial Solid Was[e Management.
b. Industrial wastewater that is being collected, accumulated, stored, or processed before discharge through any final
discharge outfall, specified by this pemtit, is considered to be industrial solid waste until the wastewater passes through
the actual point source discharge and must be managed in accordance with all applicable provisions of 30 TAC Chapter
335.
c. The perrnittee shall provide written notification, pursuant to the requirements of 30 TAC § 335.8(b)(1), to the
Corrective Action Section (MC 127) of the Remediation Division informing the Commission of any closure activity
involving an Industrial Solid Waste Management Unit, at least 90 days prior to conducting such an activity.
d. Construction of any industrial solid waste management unit requires the prior written notification of the proposed
activity to the Registration and Reporting Section (MC 129) of the Registration, Review, and Reporting Division. No
person shall dispose of industrial solid waste, including sludge or other solids from wastewater treatment processes,
prior to fulfilling the deed recordation requirements of 30 TAC § 335.5.
e. The term "industrial solid waste management unit" means a landfill, surface impoundment, waste-pile, industrial
fiunace, incinerator, cement kiln, injection well, container, drum, salt dome waste containment cavern, or any other
structure vessel, appurtenance, or other improvement on land used to tnanage industrial solid waste.
f. The permittee shall keep management records for all sludge (or other waste) removed from any wastewater treatment
process. These records shall fulfill all applicable requirements of 30 TAC Chapter 335 and must include tiie following,
as it pertains to wastewater treatment and dischazge:
i. Volume of waste and date(s) generated from treatment process;
ii. Volume of waste disposed of on-site or shipped off-site;
iii. Date(s) of disposal;
iv. Identity of hauler or transporter;
v. Location of disposal site; and
vi. Method of final disposal.
The above records shall be maintained on a monthly basis. The records shall be retained at the facility site, or shall
be readily available for review by authorized representatives of the TCEQ for at least five years.
12. For industrial facilities to which the requirements of 30 TAC Chapter 335 do not apply, sludge and solid wastes, including
tank cleaning and contaminated solids for disposal, shall be disposed of in accordance with Chapter 361 of the Texas Health
and Safety Code.
TCEQ Revision 04/2003
Page 11
TXU Generation Company LP
OTHER REOUIl2EMENTS
TPDES Permit No. 01249
1. Violations of daily maximum limitations for the following~pollutants shall be reported orally to TCEQ Region
4, within 24 hours from the time the permittee becomes aware of the violation followed by a written report '
within five days:
POLLUTANT(S) MAL (m¢/Ll
Copper (Total) 0.010
Test methods utilized to determine compliance with the permit limitations shall be sensitive enough to detect
the parameters listed above at the minimum analytical level (MAL). Permit compliance/noncompliance
determinations will be based on the effluent limitations contained in this permit with consideration given to the
MAL for toxic organic and toxic inorganic pazameters. When an analysis of an effluent sample for these
pazameters results in a measurement of less than the MAL, that pazameter shall be reported as "< (MAL value)"
and this shall be interpreted as a value of zero (0) for compliance purposes.
2. There shall be no discharge of polychlorinated biphenyl transformer fluid.
3. Daily average temperature is defined as the flow weighted average temperature (FWAT) and shall be computed
and recorded on a daily basis. FWAT shall be computed at equal time intervals not greater than two hours.
The method of calculating FWAT is as follows:
FWAT =
FLOW)
"Daily average temperature shall be the arithmetic average ofall FWAT's calculated during the calendarmonth.
"Daily maximum temperature" shall be the highest FWAT calculated during the calendaz month.
4. The term "total residua] chlorine" (or total residual oxidants for intake water with bromides) means the value
obtained using the amperometric method for total residual chlorine described in 40 CFR Part 136.
Total residual chlorine may not be dischazged from any single generating unit for more than two hours per day
unless the discharger demonstrates to the permitting authority that dischazge formore than two hours is required
for macroinvertebrate control.
Simultaneous multi-unit chlorination is permitted.
5. The term "free available chlorine" shall mean the value obtained using the amperometric titration method for
free available chlorine described in "Standard Methods for the Examination of Water and Wastewater".
Neither free available chlorine nor total residual chlorine may be discharged from any unit for more than two
hours in any one day and not more than one unit in any plant may discharge free available or total residual
chlorine at any one time unless the petmittee can demonstrate to the permitting Agency that the units in a
particular location cannot operate at or below the limitations specified in this permit.
6. The term "low volume waste sources" means wastewaters from, but not limited to: wet scrubber air pollution
control systems, ion exchange watertreatment system, watertreatmentevaporatorblowdown, boilerblowdown,
laboratory and sampling streams, floor drainage, cooling tower basin cleaning wastes, and blowdown from
recirculating house service water systems. Sanitary and air conditioning wastes are not included.
7. The term "metal cleaning waste" means any wastewater resulting from cleaning (with or without chemical
compounds) any metal process equipment including, but not limited to, boiler tube cleaning, boiler fireside
cleaning, and air preheater cleaning.
The term "chemical metal cleaning waste" means any wastewater resulting from the cleaning of any metal
Page 12
TXU Generation Company LP
TPDES Permit No. 01249
process equipment with chemical compounds, including, but not limited to, boiler tube cleaning.
8. There shall be no discharge of domestic sewage. This waste shall be routed to the City of Coppell sanitary
sewer system.
9. Chronic toxic criteria apply at the edge of the mixing zone. The mixing zone for Outfall 001 is defined as a
volume of water within a radius of 100 feet extending over the receiving water from the point where the
dischazge enters North Lake.
For the discharge from Outfall 002 to South Fork Grapevine Creek, there is no mixing zone established for this
dischazge to an intermittent stream with perennial pools. Chronic toxic criteria apply at the point ofdischarge.
For the discharge from Outfa11002 to Grapevine Creek, the mixing zone is defined as 300 feet downstream and
100 feet upstream from the point of discharge. Chronic toxic criteria apply at the edge of the mixing zone.
10. This provision supersedes and replaces Provision 1, Paragraph 1 of Monitorine and Reporting Requirements
found on Page 4 of this permit.
Monitoring results shall be provided at the intervals specified in the permit. Unless otherwise specified in this
permit or otherwise ordered by the Commission, the permittee shall conduct effluent sampling and reporting
in accordance with 30 TAC §§ 319.4 - 319.12. Unless otherwise specified, a monthly effluent report shall be
submitted each month, to the location(s) specified on the reporting form or the instruction sheet, by the 25th
day of the following month for each discharge which is described by this permit whether or not a discharge is
made for that month. Monitoring results must be reported on the approved TPDES self-report form, Discharge
Monitoring Report (DMR) Form EPA No. 3320-1, signed and certified as required by Monitoring and
Reporting Requirements No. 10.
11. Ifmore than one source is associated with this particulaz waste category, the permittee may obtain grab samples
from each source. Samples maybe analyzed individually and composited by arithmetic average or report the
highest value for reporting purposes. TXU Generation Company LP submitted a letter dated July 28, 1999
from Mr. Gerald Johnson to Mr. Chris Linendoll of the TCEQ which requested and described an alternate
sampling procedure using EPA approved method 1664A, hexane extractable material (HEM) method in order
to maintain the ability to composite samples by flow weighting from individual sources. This alternate
sampling procedure has been approved by the Executive Director of the TCEQ and maybe used to obtain oil
and grease samples as described in the letter from multiple discharge locations for a single outfall.
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TXU Generation Company LP TPDES Permit No. 01249
CHRONIC BIOMONITORING REOUIItEMENTS: FRESHWATER
The provisions of this Section apply to Outfall 001 for whole effluent toxicity testing (biomonitoring).
Scope. Frequency and Methodoloev
a. The permittee shall test the effluent for toxicity in accordance with the provisions below. Such testing
will determine if an appropriately dilute effluent sample adversely affects the survival, reproduction,
or growth of the test organism(s). Toxicity is herein defined as a statistically significant difference at
the 95% confidence level between the survival, reproduction, or growth of the test organism(s) in a
specified effluent dilution compared to the survival, reproduction, or growth of the test organism(s) in
the control (0% effluent).
b. The permittee shall conduct the following toxicity tests utilizing the test organisms, procedures and
quality assurance requirements specified in this Part of the permit and in accordance with "Short-Term
Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater
Organisms, Third Edition" (EPA-600-4-91-002), or the most recent update thereof:
1) Chronic static renewal survival and reproduction test using the water flea (Ceriodaohnia dubia
(Method 1002.0 or the most recent update thereof). This test should be terminated when 60% of
the surviving adults in the control produce three broods. This test shall be conducted once per six
months.
2) Chronic static renewal 7-day larval survival and growth test using the fathead minnow
(Pimephales romelas (Method 1000.0 or the most recent update thereof). A minimum of five
replicates with eight organisms per replicate shall be used in the control and in each dilution.
This test shall be conducted once per six months.
The permittee must perform and submit a valid test for each test species during the required reporting
period for that species. The repeat test shall include the control and all effluent dilutions and use the
appropriate number of organisms and replicates, as specified above. An invalid test is herein defined
as any test failing to satisfy the test acceptability criteria, procedures, and quality assurance
requirements specified in the test methods and permit.
c. The permittee shall use five effluent dilution concentrations and a control in each toxicity test. These
additional effluent concentrations are 32%, 42%, 56%, 75%, and 100%effluent. The critical dilution,
defined as 100% effluent, -is the effluent concentration representative of the proportion of effluent in
the receiving water during critical low flow or critical mixing conditions.
d. ThispermitmaybeamendedtorequireaWholeEflluentToxicity(WET)limit,Chemical-Specific(CS)
limits, a Best Management Practice (BMP), additional toxicity testing, and/or other appropriate actions
to address toxicity. The permittee may be required to conduct additional biomonitoring tests and/or a
Toxicity Reduction Evaluation (TRE) ifbiomonitoring data indicate multiple numbers ofunconfirmed
toxicity events.
2. Required Toxicity Testine Conditions
a. Test Acceptance -The permittee shall repeat any toxicity test, including the control and all effluent
dilutions, which fails to meet any of the following criteria:
1) a control mean survival of 80% or greater;
2) a control mean number of Ceriodaphnia dubia neonates per surviving adult of 15 or greater;
Page 14
TXU Generation Company LP TPDES Permit No. 01249
3) a control mean dry weight of surviving fathead nrinnow larvae of 0.25 mg or Beater;
4) a control Coefficient of Variation percent (CV%) of40 or less in between replicates for the young ,
ofsurviving females in the Ceriodaohnia dubia reproduction and survival test; and the gowth and
survival endpoints in the Pime hales romelas gowth and survival test.
5) a critical dilution CV% of 40 or less for young of surviving females in the Ceriodanhnia dubia
reproduction and survival test; and the growth and survival endpoints forthe Pimephales nromelas .
gowth and survival test. However, if statistically significant lethal or nonlethal effects are
exhibited at the critical dilution, a CV% greater than 40 shall not invalidate the test._
b. Statistical Interpretation
1) If the conditions of test acceptability are met and the survival of the test organism is equal to or
greater than 80% in the critical dilution and all dilutions below that, the test shall be considered
a passing test. The permittee shall report an No Observed Effect Concentration (NOEC) of not
less than the critical dilution forthe reporting requirements.
2) For the Ceriodanhnia dubia survival test, the statistical analyses used to determine if there is a
significant difference between the control and the critical dilution shall be Fisher's Exact Test as
described in the "Short-Term Methods for Estimating the Chronic Toxicity of Effluents and
Receiving Waters to Freshwater Organisms, Third Edition" (EPA/600/4-91/002), or the most
recent update thereof.
3) For the Ceriodaphnia dubia reproduction test and the fathead minnow larval survival and gowth
tests, the statistical analyses used to determine if there is a significant difference between the
control and the critical dilution shall be in accordance with the methods for determining the No
Observed Effect Concentration (NOEC) as described in the "Short-Term Methods for Estimating
the Chronic Toxicity ofEftluents and Receiving Waters to Freshwater Organisms, Third Edition"
(EPA/600/4-91/002), or the most recent update thereof.
c. Dilution Water
1) Dilution water used in the toxicity tests shall be the receiving water collected as close as possible
to the dischazge point, but unaffected by the discharge.
2) Where the receiving water proves unsatisfactory as a result of preexisting instream toxicity (i.e.
fails to fulfill the test acceptance criteria of item 2.a.), the permittee may substitute synthetic
dilution water for the receiving water in all subsequent tests provided the unacceptable receiving
water test met the following stipulations:
a) a synthetic lab water control was performed (in addition to the receiving water control)
which fulfilled the test acceptance requirements of item 2.a;
b) the test indicating receiving water toxicity was tamed out to completion (i.e., 7 days);
c) the permittee submitted all test results indicating receiving water toxicity with the reports
and information required in Part 3 of this Section.
The synthetic dilution water shall have a pH, hardness, and alkalinity similar to that of the receiving
water or a natural water in the drainage basin that is unaffected by the dischazge, provided the
magnitude of these pazameters will not cause toxicity in a synthetic dilution water control that has been
Page 15
TXU Generation Company LP
TPDES Permit No. 01249
formulated to match the pH, hardness, and alkalinity naturally found in the receiving water. Upon
approval, the permittee may substitute other appropriate dilution water with chemical and_ physical
characteristics similar to that of the receiving water.
d. Samples and Composites
1) The permittee shall collect a minimum of three flow-weighted 24-hour composite samples from
Outfall 001. The second and third 24-hour composite samples will be used for the renewal of the
dilutionconcentrationsforeachtoxicitytest. A24-hour compositesamp]econsistsofaminimum
of 12 effluent portions collected at equal time intervals representative of a 24-hour operating day
and combined proportionally to flow, or a sample continuously collected proportionally to flow
over a 24-hour operating day.
2) The permittee shall collect the 24-hour composite samples such that the samples are
representative of any periodic episode of chlorination, biocide usage, or other potentially toxic
substance discharged on an intermittent basis.
3) The permittee shall initiate the toxicity tests within 36 hours after collection of the last portion
of the first 24-hour composite sample. The holding time for any subsequent 24-hour composite
sample shall not exceed 72 hours. Samples shall be maintained at a temperature of 4 degrees
Centigrade during collection, shipping, and storage.
4) If flow from the outfall being tested ceases during the collection of effluent samples, the
requirements for the minimum number of effluent samples, the minimum number of effluent
portions, and the sample holding time, aze waived during that sampling period. However, the
permittee must have collected an effluent composite sample volume sufficient to complete the
required toxicity tests with daily renewal of the effluent. When possible, the effluent samples
used for the toxicity tests shall be collected on separate days if the dischazge occurs over multiple
days. The effluent composite sample collection duration and the static renewal protocol
associated with the abbreviated sample collection must be documented in the full report required
in Part 3 of this Section.
Reportine
All reports, tables, plans, summaries, and related correspondence required in any Part of this Section shall
be submitted to the attention of the Water Quality Assessment Team (MC 150) of the Water Permits &
Resource Management Division.
a. The permittee shall prepare a full report of the results of al] tests conducted pursuant to this permit in
accordance with the Report Preparation Section of "Short-Term Methods for Estimating the Chronic
Toxicity of Effluents and Receiving Waters to Freshwater Organisms, Third Edition" (EPA 600/4-
91/002), or the most recent update thereof, for every valid and invalid toxicity test initiated whether
carried to completion or not. All full reports shall be retained for 3 years at the plant site and shall be
available for inspection by TCEQ personnel.
b. A full report must be submitted with the first valid biomonitoring test results for each test species and
with the first test results any time the permittee subsequently employs a different test laboratory. Full
reports need not be submitted for subsequent testing unless specifically requested. The permittee shall
routinely report the results of each biomonitoring test on the Table 1 forms provided with this permit.
All Table I reports must include the information specified in the Table 1 form attached to this pemrit.
1) Annual biomonitoring test results aze due on orbefore January 20th for biomonitoring conducted
during the previous 12 month period.
Page 16
TXU Generation Company LP TPDES Permit No. 01249
2) Semiannual biomonitoring test results are due on or before July 20th and January 20th for
biomonitoring conducted during the previous 6 month period.
3) Quarterly biomonitoring test results are due on or before April 20th, July 20th, October ZOth, and
January 20th, for biomonitoring conducted during the previous calendar quarter.
4) Monthly biomonitoring test results are due on or before the 20th day of the month following
sampling.
c. Enter the following codes on the DMR for the appropriate pazameters for valid tests only:
1) For the water flea, Pazameter TLP3B, enter a "1" ifthe NOEC for survival is less than the critical
dilution; otherwise, enter a "0."
2) For the water flea, Pazameter TOP3B, report the NOEC for survival.
3) For the water flea, Parameter TPP3B, report the NOEC for reproduction.
4) For the fathead minnow, Parameter TLP6C,enter a "1" if the NOEC for survival is less than the
critical dilution; otherwise, enter a "0."
5) For the fathead minnow, Parameter TOP6C, report the NOEC for survival.
6) For the fathead minnow, Pazameter TPP6C, report the NOEC for growth.
d. Enter the following codes on the DMR for retests only:
1) For retest number 1, Parameter 22415, enter a "1" if the NOEC for survival is less than the critical
dilution; otherwise, enter a "0."
2) For retest number 2, Parameter 22416, enter a "1" if the NOEC for survival is less than the critical
dilution; otherwise, enter a "0."
4. Persistent Lethality
The requirements of this Part apply only when a toxicity test demonstrates significant lethality at the critical
dilution. Significant lethality is defined as a statistically significant difference, at the 95% confidence level,
between the survival of the test organism in a specified effluent dilution when compared to the survival of the
test organism in the control.
a. The permittee shall conduct a total of two additional tests (retests) for any species that demonstrates
significant lethality at the critical dilution. The two retests shall be conducted monthly during the next
two consecutive months. The permittee shall not substitute either of the two retests in lieu of routine
toxicity testing. All reports shall be submitted within 20 days of test completion. Test completion is
defined as the last day of the test. The retests shall also be reported on the DMRs as specified in Part
3.d.
b. If one or both of the two retests specified in item 4.a. demonstrates significant lethality at the critical
dilution, the permittee shall initiate the T12E requirements as specified in Part 5.
c. The provisions of item 4.a. are suspended upon completion ofthe two retests and submittal of the THE
Action Plan and Schedule defined in Part 5 of this Section.
Page 17
TXiJ Generation Company LP
5. Toxiciri Reduction Evaluation
TPDES Permit No. 01249
a. Within 45 days of the last test day of the retest that confirms significant lethality at the critical dilution, _
the pemtittee shall submit a General Outline for initiating a TRE. The outline shall include, but not be
limited to, a description of project personnel, a schedule for obtaining consultants (if needed), a
discussion of influent and/or effluent data available for review, a sampling and analytical schedule, and
a proposed THE initiation date.
b. Within 90 days of the last test day of the retest that confirms significant lethality at the critical dilution,
the permittee shall submit a THE Action Plan and Schedule for conducting a TRE. The plan shall
specify the approach and methodology to be used in performing the TRE. A Toxicity Reduction
Evaluation is astep-wise investigation combining toxicity testing with physical and chemical analysis
to determine actions necessary to eliminate or reduce effluent toxicity to a level not effecting significant
lethality at the critical dilution. The THE Action Plan shall lead to the successful elimination of
significant lethal effects at the critical dilution for both test species defined in item l.b. As a minimum,
the THE Action Plan shall include the following:
1) Specific Activities - The THE Action Plan shall specify the approach the permittee intends to
utilize in conducting the TRE, including toxicity characterizations, identifications, confirmations,
source evaluations, treatability studies, and/or alternative approaches. When conducting
characterization analyses, the permittee shall perform multiple characterizations and follow the
procedures specified in the document entitled, "Toxicity Identification Evaluation:
Characterization of Chronically Toxic Effluents, Phase I" (EPA/600/6-91/OOSF), or alternate
procedures. Thepermittee shall performmultiple identifications and follow the methods specified
in the documents entitled, "Methods for Aquatic Toxicity Identification Evaluations, Phase II
Toxicity IdentificationProcedures for Samples ExhibitingAcute and Chronic Toxicity" (EPA/60-
0/R-92/080) and "Methods for Aquatic Toxicity Identification Evaluations, Phase III Toxicity
Confirmation Procedures for Samples Exhibiting Acute and Chronic Toxicity" (EPA/600/R-
92/O81). All characterization, identification, and confirmation tests shall be conducted in an
orderly and logical progession;
2) Sampling Plan -The THE Action Plan should describe sampling locations, methods, holding
times, chain of custody, and preservation techniques. The effluent sample volume collected for
all tests shall be adequate to perform the toxicity characterization/ identification/ confirmation
procedures, and chemical-specific analyses when the toxicity tests show significant lethality.
Where the permittee has identified or suspects specific pollutant(s) and/or source(s) of effluent
toxicity, the permittee shall conduct, concurrent with toxicity testing, chemical-specific analyses
for the identified and/or suspected pollutant(s) and/or source(s) of effluent toxicity;
3) Quality Assurance Plan -The THE Action Plan should address record keeping and data
evaluation, calibration and standardization, baseline tests, system blanks, controls, duplicates,
spikes, toxicity persistence in the samples, randomization, reference toxicant control charts, as
well as mechanisms to detect artifactual toxicity; and
4) Project Organization -The THE Action Plan should describe the project staff, project manager,
consulting engineering services (where applicable), consulting analytical and toxicological
services, etc.
c. Within 30 days of submittal of the THE Action Plan and Schedule, the permittee shall implement the
THE with due diligence.
d. The permittee shall submit quarterly THE Activities Reports concerning the progress of the TRE. The
quarterly reports are due on or before Apri120th, July 20th, October 20th, and January 20th. The report
Page 18
TXU Generation Company LP TPDES Permit No. 01249
shall detail information regarding the THE activities including:
1) results and interpretation of any chemical specific analyses for the identified and/or suspected
pollutant(s) performed during the quarter;
2) results and interpretation ofanycharacterization,identification, andconfirmationtestsperformed ,
during the quarter;
3) any data and/or substantiating documentation which identifies the pollutant(s) and/or source(s)
of effiuent toxicity;
4) results of any studies/evaluations concerning the treatability of the facility's effluent toxicity;
5) any data which identifies effluent toxicity control mechanisms that will reduce effluent toxicity
to the level necessary to meet no significant lethality at the critical dilution; and
6) any changes to the initial THE Plan and Schedule that aze believed necessary as a result of the
THE fmdings.
Copies of the THE Activities Report shall also be submitted to the U.S. EPA Region 6 office (6WQ-PI)
and the TCEQ Region 4 Office.
e. During the TRE, the permittee shall perform, at a minimum, quarterly testing using the more sensitive
species; testing for the less sensitive species shall continue at the frequency specified in Part l.b. If the
effiuent ceases to effect significant lethality (herein as defined below) the permittee may end the TRE.
A "cessation of lethality" is defined as no significant lethality at the critical dilution for a period of 12
consecutive months with at least monthly testing. At the end of the 12 months, the permittee shall
submit a statement of intent to cease the THE and may then resume the testing frequency specified in
Part I.b.
This provision does not apply as a result of corrective actions taken by the permittee. "Corrective
actions" are herein defined as proactive efforts which eliminate or reduce effluent toxicity. These
include, but are not limited to, source reduction or elimination, improved housekeeping, changes in
chemical usage, and modifications of influent streams and/or effluent treatment.
The permittee may only apply this cessation of lethality provision once. If the effiuent again
demonstrates significant lethality to the same species, then this permit will be amended to add a WET
limit with a compliance period, if appropriate. However, prior to the effective date of the WET limit,
the permittee may apply for a permit amendmentremovingthe WET limit, in lieu ofan alternate toxicity
control measure, by identifying and confirming the toxicant and/or an appropriate control measure.
f. The permittee shall complete the THE and submit a Final Report on the THE Activities no later than
28 months from the last test day of the retest that confirmed significant lethal effects at the critical
dilution. The permittee may petition the Executive Director (in writing) for an extension of the 28-
monthlimit. However, to warrant an extension the permittee must have demonstrated due diligence in
their pursuit of the TIElTRE and must prove that circumstances beyond their control stalled the
TIE/'I'RE. The report shall provide informationpertainingtothespecificcontro]mechanism(s)selected
that will, when implemented, result in reduction of effluent toxicity to no significant lethality at the
critical dilution. The report will also provide a specific corrective action schedule for implementing the
selectedcontrolmechanism(s). CopiesoftheFinalReportontheTREActivitiesshallalsobesubmitted
to the U.S. EPA Region 6 office (6WQ-PI) and the TCEQ Region 4 office.
Page 19
TXU Generation Company LP
TPDES Permit No. 01249
g. Based upon the results of the THE and proposed corrective actions, this permit may be amended to
modify_the biomonitoring requirements where necessary, to require a compliance schedule for
implementation of corrective actions, to specify a WET limit, to specify a BMP, and/or to specify
Chemical-Specific (CS) limits.
Page 20
TXU Generation Company LP
TPDES Permit No. 01249
TABLE 1 (SHEET' 1 OF 4)
BIOMONTTORING REPORTING
CERIODAPHNIA DUBIA SURVIVAL AND REPRODUCTION
Date Time Date Time
Dates and Times No. 1 FROM: TO:
Composites
Collected No.2 FROM: TO:
No.3 FROM: TO:
Test initiated: am/pm date
Dilution water used: Receiving Water Synthetic Dilution Water
NUMBER OF YOUNG PRODUCED PER ADULT AT END OF TEST
Percehf'e$Iuerit' % ~~~
':' ~ ~ r _.
REP -- - - 0% - 32"/0 - 42% c~`' S6°r ;.e x`-75%' : 100%-
A
B ~`
~G
._f _..
,
D,, ~..-.
,~
F
_::: ~-
_:G - '_
,H -' .;
~, I ~-'.
J ,
Surviv. Mem s. t~+..
Tool Mm '
CV%#~
"`coefficient of variation = standazd deviation x 100/mean (calculation based -on young of the surviving adults)
Designate males (M), and dead females (D), along with number of neonates (x) released prior to death.
Page 21 '
TXU Generation Company LP
TABLE 1 (SHEET 2 OF 4)
BIOMONTTORING REPORTING
TPDES Permit No. 01249
CERIODAPHNIA DUBIA SURVNAL AND REPRODUCTION TEST
1. Dunnett's Procedure or Steel's Many-One Rank Test or Wilcoxon Rank Sum Test (with Bonfenoni
adjustment) or t-test (with Bonferroni adjustment) as appropriate:
Is the mean number of young produced per adult significantly less (p=0.05) than the number of young per
adult in the control for the % effluent corresponding to significant nonlethal effects?
CRITICAL DILUTION (100%): YES NO
PERCENT SURVNAL
~~ ~ ~*~ ~. ~ ,;Percent etlluept ~` ~~ ~,~,~ } ~ ~
`
.. .~ .1_..
l a zs,..aa
~ '4.`~'. a; )'SV~..:. ~ -
~~ ,.:ts~
y„-3vdk
6
' ~7'c.~l~r E, jv.. ...t g+~vk63
~~
Time of Rea
m 0% ~ 32% ~ - 42% - 5
°10 ...75% '? 100%' ;
- --
.z
,
,
~ .
24h <
_ ~ ~~.
h
°4
~
._i~,.k
~+" >--;.
~' End o~Test'~ `', ,'
m..~ '~`
>t,. ,
2.- Fisher's Exact Test:
Is the mean survival at test end significantly less (p=0.05) than the control survival for the % effluent
corresponding to lethality?
CRITICAL DILUTION (100%): YES NO
3. Enter percent effluent corresponding to each NOEC below
a.) NOEC survival = % effluent
b.) NOEC reproduction = % effluent
Page 22 '
TXU Generation Company LP
TPDES Permit No. 01249
TABLE 1 (SHEET'3 OF 4)
BIOMONITORING REPORTING
FATHEAD MINNOW LARVAE GROWTH AND SURVNAL
Date Time
Dates and Times No. 1 FROM: TO:
Composites
Collected No.2 FROM: TO:
No.3 FROM: TO:
Date Time
Test initiated: am/pm date
Dilution water used: Receiving Water Synthetic Dilution Water
FATFTFArI MiT.TT.Tnw l:AnW'i'Gr Tl eTe
Effluent Average Dry Werght m rml~igrams ' ~ Mean 4' k~ -
Concentration (%} <.:
m r hat
m'liei
a"' E '
h
'"D
`er'=''
'~ y` x'~ ?
e c
a
s ry `
~ .er ~r~
; s~,~erght;~ s
' e~%
~m. .
,~ .
- , - O%} 4x ~r~~,
42%~^' max
rx ~y
r ~;
° u
~
__ .56/0
._._ _
.
100% '~ -
* coefficient of variation = standazd deviation x 100/mean
1. Dunnett's Procedure or Steel's Many-One Rank Test or Wilcoxon Rank Sum Test (with Bonferroni
adjustment) or t-test (with Bonferroni adjustment) as appropriate:
Is the mean dry weight (growth) at 7 days significantly less (p=0.05) than the control's dry weight (growth)
for the % effluent corresponding to significant nonlethal effects?
CRITICAL DILUTION (100%): YES NO
Page 23 '
TXLT Generation Company LP
TABLE 1 (SHEET 4 OF 4)
BIOMONITORING REPORTING
FATHEAD MINNOW GROWTH AND SURVIVAL TEST
FATFTF D P A.frATT.Tllvl) nT me rn r. , .~
TPDES Permit No. 01249
------~ •l Vl\YlYA~ . Lt11 t1
~'t ...:
,, tEfl7uent n Sx ,:
"' , Percent Sui•vtv`al in "~~;~
'~~
~~~"~ ~"`~'~
i "
Concentration 'f ".~ `` hcate,chambers '' ~~.. ,
a~f,~`sWvi ~ a o
n ~ ,,4 ~
Aa sr <.~
~- B ~'
C ~ .i
r D zi
$
4b
~
metro
r 0°/O "
s
' `32%
r.-z "
56%' "
( 75%
100% - ' - -
* coefficient of variation =standard deviation x 100/mean
2. Dunnett's Procedure or Steel's Many-One Rank Test or Wilcoxon Rank Sum Test (with Bonferroni
adjustment) or t-test (with Bonferroni adjustment) as appropriate:
Is the mean survival at 7 days significantly less (p=0.05) than the control survival for the % etlluent
corresponding to lethality?
CRITICALDII.UTION (100%): YES NO
3. Enter percent effluent corresponding to each NOEC below:
a.) NOEC survival = % effluent
b.) NOEC growth = % effluent
Page 24
TXU Generation Company LP TPDES Permit No. 01249
24-HOUR ACUTE BIOMONITORING REOUIREMENTS• FRESHWATER
The provisions of this Section apply individually and separately to Outfal] 001 for whole effluent toxicity testing
(biomonitoring). No samples or portions of samples from one outfall maybe composited with samples or portions
of samples from another outfall.
1. Scone. Frecuencv and Methodoloev
a. The permittee shall test the effluent for lethality in accordance with the provisions in this Section. Such
testing will determine compliance with the Surface Water Quality Standard, 30 TAC §307.6(e)(2)(B),
of greater than 50% survival of the appropriate test organisms in 100% effluent fora 24-hour period.
b. The toxicity tests specified shall be conducted once per six months. The permittee shall conduct the
following toxicity tests utilizing the test organisms, procedures, and quality assurance requirements
specified in this section of the permit and in accordance with "Methods for Measuring the Acute
Toxicity of Effluents and Receiving Waters to Freshwater and Marine Organisms, Fourth Edition" (EPA
600/4-90/027F), or the most recent update thereof:
1) Acute 24-hour static toxicity test using the water flea a hnia ulex . A minimum of five
replicates with eight organisms per replicate shall be used in the control and in each dilution.
2) Acute 24-hour static toxicity test using the fathead minnow (Pimephales romelas . A minimum
of five replicates with eight organisms per replicate shall be used in the control and in each
dilution.
A valid test result must be submitted for each reporting period. The permittee must report, then repeat,
an invalid test during the same reporting period. The repeat test shall include the control and the 100%
effluent dilution and use the appropriate number of organisms and replicates, as specified above. An
invalid test is herein defined as any test failing to satisfy the test acceptability criteria, procedures, and
quality assurance requirements specified in the test methods and permit.
c. In addition to an appropriate control, a 100% effluent concentration shall be used in the toxicity tests.
Except as discussed in item 2.b, the control and/or dilution water shall consist of a standard, synthetic,
moderately hard, reconstituted water.
d. This permit may be amended to require a Whole Effluent Toxicity (WET) limit, a Best Management
Practice (BMP), Chenvcal-Specific (CS) limits, additional toxicity testing, and/or other appropriate
actions to address toxicity. The permittee may be required to conduct additional biomonitoring tests
and/or a Toxicity Reduction Evaluation (TRE) if biomonitoring data indicate multiple numbers of
unconfirmed toxicity events.
e. If the biomonitoring dilution series specified in the Chronic biomonitoring requirements includes a
100% effluent concentration, those results may fulfill the requirements of this Section. The results of
any test with a 100% effluent concentration performed in the proper time interval may be substituted
in lieu of performing a separate 24-hour acute test. Compliance will be evaluated as specified in item
a. The greater than 50% survival in 100% effluent fora 24-hour period standard applies to all tests
utilizing a 100% effluent dilution, regardless of whether the results aze submitted to comply with the
minimum testing frequency defined in item b.
2. Required Toxiciri Testine Conditions
a. Test Acceptance -The permittee shall repeat any toxicity test, including the control, if the control fails
to meet a mean survival equal to or greater than 90%.
Page 25
TXU Generation Company LP
TPDES Permit No. 01249
b. Dilution Water - In accordance with item l.c., the control and/or dilution water shall normally consist
of a standard, synthetic, moderately hard, reconstituted water. If the pemuttee utilizes the results of a
48-How Acute test or a Chronic test to satisfy the requirements in item l.e., the permittee may use the
receiving water or dilution water that meets the requirements of item 2.a. as the control and dilution
water.
c. Samples and Composites
1) The permittee shall collect one flow-weighted 24-how composite sample from Outfa11001. A
24-how composite sample consists of a minimum of 12 effluent portions collected at equal time
intervals representative of a 24-how operating day and combined proportional to flow, or a
sample continuously collected proportional to flow over a 24-how operating day.
2) The permittee shall collect the 24-how composite samples such that the samples aze
representative of any periodic episode of chlorination, biocide usage, or other potentially toxic
substance discharged on an intermittent basis.
3) The permittee shall initiate the toxicity tests within 36 hours after collection of the last portion
of the 24-how composite sample. Samples shall be maintained at a temperatwe of 4 degees
Centigade during collection, shipping, and storage.
4) If the Outfall ceases discharging during the collection of the effluent composite sample, the
requirements for the minimum number of effluent portions are waived. However, the permittee
must have collected a composite sample volume sufficient for completion of the required test.
The abbreviated sample collection, dwation, and methodology must be documented in the full
report required in Part 3 of this Section.
3. Reoortine
All reports, tables, plans, summaries, and related correspondence required in any Part of this Section shall
be submitted to the attention of the Water Quality Assessment Team (MC 150) of the Water Permits &
Resowce Management Division.
a. The permittee shall prepare a full report of the results of all tests conducted pursuant to this permit in
accordance with the Report Preparation Section of "Methods for Measuring the Acute Toxicity of
Eflluents and Receiving Waters to Freshwater and Marine Organisms, Fourth Edition" (EPA 600/4-
90/027F), or the most recent update thereof, for every valid and invalid toxicity test initiated. Al] full
reports shall be retained for three years at the plant site and shall be available for inspection by TCEQ
personnel.
b. A full report must be submitted with the first valid biomonitoring test results for each test species and
with the first test results any time the permittee subsequently employs a different test laboratory. Full
reports need not be submitted for subsequent testing unless specifically requested. The permittee shall
routinely report the results of each biomonitoring test on the Table 2 forms provided with this permit.
All Table 2 reports must include the information specified in the Table 2 form attached to this pemrit.
1) Semiannual biomonitoring test results are due on or before January 20th and July 20th for
biomonitoring conducted during the previous 6 month period.
2) Quarterly biomonitoring test results are due on or before January 20th, April 20th, July 20th, and
October 20th, for biomonitoring conducted during the previous calendar quarter.
c. Enter the following codes on the DMR for the appropriate parameters for valid tests only:
1) For the water flea, Parameter TIE3D, enter a "0" if the mean survival at 24-hows is Beater than
Page 26
TXU Generation Company LP
TPDES Permit No. 01249
50% in the 100% effluent dilution; if the mean survival is less than or equal to 50%, enter a "1."
2) For the fathead minnow, Parameter TIE6C, enter a "0" if the mean survival at 24-hours is Beater
than 50% in the 100% effluent dilution; if the mean survival is less than or equal to 50%, enter
a "1."
4. Persistent Mortaliri
The requirements of this Part apply when a toxicity test demonstrates significant lethality, here defined as a
mean mortality of 50% or Beater to organisms exposed to the 100% effluent concentration after 24-hours.
a. The permittee shall conduct two additional tests (retests) for each species that demonstrates significant
lethality. The two retests shall be conducted once per week for two weeks. Five effluent dilution
concentrations in addition to an appropriate control shall be used in the retests. These additional
effluent concentrations are 6%, 13%, 25%, 50% and 100% effluent. The first retest shall be conducted
within 15 days ofthe laboratory detemrination of significant lethality. All test results shall be submitted
within 20 days of test completion of the second retest. Test completion is defined as the 24th hour.
b. If one or both of the two retests specified in item 4.a. demonstrates significant lethality, the permittee
shall initiate the THE requirements as specified in Part 5 of this Section.
Toxicity Reduction Evaluation
a. Within 45 days of the retest that demonstrates significant lethality, the permittee shall submit a General
Outline for initiating a TRE. The outline shall include, but not be limited to, a description of project
personnel, a schedule for obtaining consultants (ifneeded), a discussion of influent and/or effluent data
available for review, a sampling and analytical schedule, and a proposed THE initiation date.
b. Within 90 days of the retest that demonstrates significant lethality, the permittee shall submit a THE
Action Plan and Schedule for conducting a TRE. The plan shall specify the approach and methodology
to be used in performing the TRE. A Toxicity Reduction Evaluation is a step-wise investigation
combining toxicity testing with physical and chemical analysis to determine actions necessary to
eliminate or reduce effluent toxicity to a level not effecting significant lethality at the critical dilution.
The THE Action Plan shall lead to the successful elimination of significant lethality for both test species
defined in item l.b. As a minimum, the THE Action Plan shall include the following:
1) Specific Activities - The THE Action Plan shall specify the approach the permittee intends to
utilize in conducting the TRE, includingtoxicitycharacterizations,identifications, confirmations,
source evaluations, treatability studies, and/or alternative approaches. When conducting
characterization analyses, the permittee shall perform multiple characterizations and follow the
procedures specified in the document entitled, "Methods for Aquatic Toxicity Identification
Evaluations: Phase I Toxicity Chazacterization Procedures" (EPA/600/6-91/003), or alternate
procedures. The permittee shall perform multiple identifications and follow the methods specified
in the documents entitled, "Methods for Aquatic Toxicity Identification Evaluations, Phase II
Toxicity Identification Procedures for Samples ExhibitingAcute and Chronic Toxicity" (EPA/60-
0/R-92/080) and "Methods for Aquatic Toxicity Identification Evaluations, Phase III Toxicity
Confirmation Procedures for Samples Exhibiting Acute and Chronic Toxicity" (EPA/600/R-
92/O81). All characterization, identification, and confirmation tests shall be conducted in an
orderly and logical progession;
2) Sampling Plan -The THE Action Plan should describe sampling locations, methods, holding
times, chain of custody, and preservation techniques. The effluent sample volume collected for
all tests shall be adequate to perform the toxicity chazacterization/ identification/ confirmation
procedures, and chemical-specific analyses when the toxicity tests show significant lethality.
Where the permittee has identified or suspects specific pollutant(s) and/or source(s) of effluent
Page 27
TXU Generation Company LP
TPDES Pernilt No. 01249
toxicity, the permittee shall conduct, concurrent with toxicity testing, chemical-specific analyses
for the identified and/or suspected pollutant(s) and/or source(s) of effluent toxicity; _ * .
3) Quality Assurance Plan -The THE Action Plan should address record keeping and data
evaluation, calibration and standardization, baseline tests, system blanks, controls, duplicates,
spikes, toxicity persistence in the samples, randomization, reference toxicant control charts, as
well as mechanisms to detect artifactual toxicity; and
4) Project Organization -The THE Action Plan should describe the project staff, project manager,
consulting engineering services (where applicable), consulting analytical and toxicological
services, etc.
c. Within 30 days of submittal of the THE Action Plan and Schedule, the pemtittee shall implement the
THE with due diligence.
d. The permittee shall submit quarterly THE Activities Reports concerning the progress of the TRE. The
quarterly THE Activities Reports are due on or before Apri120th, July 20th, October 20th, and January
20th. The report shall detail information regarding the THE activities including:
1) results and interpretation of any chemical-specific analyses for the identified and/or suspected
pollutant(s) performed during the quarter;
2) results and interpretationofanycharacterization,identification, andconfirmationtests.performed
during the quarter;
3) any data and/or substantiating documentation which identifies the pollutant(s) and/or source(s)
of effluent toxicity;
4) results of any studies/evaluations concerning the treatability of the facility's effluent toxicity;
5) any data which identifies effluent toxicity control mechanisms that will reduce effluent toxicity
to the level necessary to eliminate significant lethality; and
6) any changes to the initial THE Plan and Schedule that are believed necessary as a result of the
THE findings.
Copies of the THE Activities Report shall also be submitted to the U.S. EPA Region 6 office (6WQ-PI)
and the TCEQ Region 4 office.
e. During the TRE, the permittee shall perform, at a minimum, quarterly testing using the more sensitive
species; testing for the less sensitive species shall continue at the frequency specified in Part l.b. If the
effluent ceases to effect significant lethality (herein as defined below) the pemuttee may end the TRE.
A "cessation of lethality" is defined as no significant lethality at the critical dilution for a period of 12
consecutive weeks with at least weekly testing. At the end of the 12 weeks, the pemrittee shall submit
a statement of intent to cease the THE and may then resume the testing frequency specified in Part l .b.
This provision does not apply as a result of corrective actions taken by the permittee. "Corrective
actions" are herein defined as proactive efforts which eliminate or reduce effluent toxicity. These
include, but are not limited to, source reduction or elimination, improved housekeeping, changes in
chemical usage, and modifications of influent streams and/or effluent treatment.
The permittee may only apply this cessation of lethality provision once. If the effluent again
demonstrates significant lethality to the same species, then this permit will be amended to add a WET
limit with a compliance period, if appropriate. However, prior to the effective date of the WET limit,
the permittee may apply for a permit amendment removing the WET limit, in lieu ofan alternate toxicity
Page 28
TXU Generation Company LP
TPDES Permit No. 01249
control measure, by identifying and confirming the toxicant and/or an appropriate control measure.
f The pemrittee shall complete the THE and submit a Final Report on the THE Activities no later than
18 months from the last test day of the retest that demonstrates significant lethality. The permittee may
petition the Executive Director (in writing) for an extension ofthe 18-month limit. However, to warrant
an extension the permittee must have demonstrated due diligence in their pursuit of the TIE/TRE and
must prove that circumstances beyond their control stalled the TIE/TRE. The report shall specify the
control mechanism(s) that will, when implemented, reduce etfluenttoxicity as specified in item S.g. The
report will also specify a corrective action schedule for implementing the selected control
mechanism(s). The permittee shall also submit copies of the Final Report on the THE Activities to the
U.S. EPA Region 6 office (6WQ-PI) and the TCEQ Region 4 office.
g. Within three years of the last day of the test confirming toxicity, the permittee shall comply with 30
TAC 307.6.(e)(2)(B), which requires greater than 50% survival of the test organism in 100% etlluent
at the end of 24-hours. The permittee may petition the Executive Director (in writing) for an extension
of the 3-year limit. However, to warrant an extension the permittee must have demonstrated due
diligence in their pursuit ofthe TIE/TRE and must prove that circumstances beyond their control stalled
the TIE/TRE.
The requirement to comply with 30 TAC 307.6.(e)(2)(B)may be exempted upon proof that toxicity is
caused by an excess, imbalance, or deficiency of dissolved salts. This exemption excludes instances
where individually toxic components (e.g. metals) form a salt compound. Following the exemption, the
permit may be amended to include an ion-adjustment protocol, alternate species testing, or single
species testing.
h. Based upon the results of the THE and proposed corrective actions, this permit may be amended to
modify the biomonitoring requirements where necessary, to require a compliance schedule for
implementation of corrective actions, to specify a WET limit, to specify a BMP, and/or to specify a
Chemical-Specific (CS) limit(s).
Page 29
TXU Generation Company LP
TABLE 2 (SHEET 1 OF 2)
WATER FLEA SURVNAL
GENERAL INFORMATION
TPDES Permit No. 01249
'~•
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PERCENT SURVNAL
Time Rep Percent effluent %)
0% 6% 13% 25% 50% 100%
A
24h B
C
D
E
MEAN'
Enter percent effluent corresponding to the LC50 below:
24 hour LC50 a hnia or Ceriodanhnia) _ % effluent
(circle appropriate genus)
95% confidence limits:
Method of LC50 calculation:
If 24-hour survivorship data from the chronic Ceriodaohnia dubia test is being used, the mean survival per
dilution for all 10 replicates shall be reported on this row.
Page 30
TXU Generation Company LP
_ . TABLE 2 (SHEET 2 OF 2)
FATHEAD MINNOW SURVNAL
GENERAL INFORMATION
TPDES Permit No. 01249
T
~
une ahm ^
~ yS~ :~Dat -
3 rt
~°~ ~ `` ~n Co £ ;srte Sa , le ~9Uecfeii~ -
~. , ,
'"
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Test I
tiated'~ P ~`
~. ~, -
PERCENT SURVNAL
Time Rep Percent effluent
0% 6% 13% 25% 50% 100%
A
24h B
C
D
E
MEAN
Enter percent effluent corresponding to the LC50 below:
24 hour LC50 (Pimeohales) _ % effluent
95% confidence limits:
Method of LC50 calculation:
Page 31
STATEMENT OF BASIS/TECIINICAL SUMMARY AND
EXECUTIVE DIItECTOR'S PRELIMINARY DECISION
DESCRIPTION OF APPLICATION -
Applicant: TXU Generation Company LP; Texas Pollutant Discharge Elimination System (TPDES)
Permit No. 01249 (TX0030295).
Regulated Activity: Industrial Wastewater Permit.
Type of Application: Renewal.
Request: Renewal with changes to the location description of the facility.
Authority: Federal Clean Water Act -Section 402; Texas Water Code § 26.027; 30 TAC Chapter 305,
Subchapters C-F, Chapters 307 and 319, Commission Policies and EPA Guidelines.
EXECUTIVE DIRECTOR RECOMMENDATION
The Executive Director has made a preliminary decision that this permit, if issued, meets all statutory and regulatory
requirements. It is proposed the permit be issued to expire on October 1, 2006 in accordance with 30 TAC Section
305.71, Basin Permitting.
REASON FOR PROJECT PROPOSED
The applicant has applied to the TCEQ for a renewal of its existing permit.
PROJECT DESCRIPTION AND LOCATION
The applicant operates the North Lake Steam Electric Station.
The wastewater system consists ofonce-through cooling water that is withdrawn from North Lake and dischazged
via a canal into North Lake. This once-through cooling water is periodically chlorinated and dischazged via Outfall
001. The chlorine dissipates into the atmosphere and the cooling pond (North Lake) removes heat from the water.
Periodically, metal cleaning wastes are treated to remove copper and iron and then routed into the low volume waste
treatment facility for neutralization for discharge via internal Outfall 101 (prior to commingling with the once-
throughcooling water). Some low volume wastes, including boiler blowdown, also discharge via Outfall 101. All
of these waste streams are monitored prior to discharge into the once-through cooling water canal. Other low
volume wastes are routed into three (3) oil/water separators (northeast, northwest and southeast) for treatment and
discharge via Outfall 002. Storm water runoff collected in yard drains is also routed through the oil water
separators. Domestic wastes are collected and routed into the City of Coppell sanitary sewer system.
The plant site is located at 14901 North Lake Road on the north shore of North Lake immediately southeast of the
Moore Road and Belt Line Road intersection, approximately one mile east of the City of Coppell, Dallas County,
Texas.
The effluent is discharged from Outfall 001 via the once-through cooling discharge canal to North Lake; thence
either via the blowdown-receiving structure to the Elm Fork Trinity River below Lewisville Lake in Segment No.
0822 of the Trinity River Basin; or via the reservoir spillway to the South Fork of Grapevine Creek; thence to
Grapevine Creek; thence to the Elm Fork Trinity River below Lewisville Lake in Segment No. 0822 of the Trinity
River Basin; and from Outfa11002 to the South Fork of Grapevine Creek; thence to Grapevine Creek; thence to the
Elm Fork Trinity River below Lewisville Lake in Segment No. 0822 of the Trinity River; and/or to Grapevine
Creek; thence to Elm Fork Trinity River below Lewisville Lake in Segment No. 0822 of the Trinity River Basin.
Stream Segment No. 0822 is water quality limited. The unclassified receiving waters have a high aquatic life use
for North Lake and Grapevine Creek and a limited aquatic life use for the South Fork of Grapevine Creek. The
designated uses for Segment No. 0822 are high aquatic life use, contact recreation, and public water supply. The
Page 1
STATEMENT OF BASIS/TECHNICAL SUMMARY AND
EXECUTIVE DIItECTOR'S PRELIMINARY DECISION
TPDES Permit No, 01249
effluent limits in the draft permit will maintain and protect the existing instream uses. All determinations aze
preliminary and subject to additional review and/or revisions.
There is no priority watershed of critical concern with respect to endangered and threatened species in Segment No.
0822 in Dallas County. Therefore, no endangered or threatened aquatic or aquatic dependent species (including
proposed species) occur in this area. This determination was made by referencing Appendix A of the U.S. Fish and
Wildlife Service biological opinion, dated September 14, 1998, on the State of Texas authorization of the Texas
Pollutant Discharge Elimination System. This is a renewal of the existing permit with no change in the pernritted
flow. Due to the low level ofoxygen-demanding constituents in the wastewater, no significant dissolved oxygen
depletion is expected as a result of this discharge.
Segment No. 0822 is currently listed on the State's inventory of impaired and threatened waters (the Clean Water
Act Section 303(d) list). The listing is specifically for depressed dissolved oxygen concentrations in the upper 15
miles of the segment and for elevated lead concentrations throughout the segment. The discharger is in the
dissolved oxygen impaired portion of the segment. The dischazge should not cause or contribute to further
impairment because this permit does not authorize an increase in discharge over the previous pemut and nor does
the permit authorize the discharge ofdomestic wastes. Domestic wastes are routed to the publicly-owned treatment
works.
SUMMARY OF EFFLUENT DATA
The following is a quantitative description of the dischazge described in the Monthly Effluent Report data for the
period November 1999 through Apri12001. The "Average of Daily Avg" values presented in the following table
are the average of all daily average values for the reporting period for each parameter. The "Maximum of Daily
Max" values presented in the following table are the individual maximum values for the reporting period for each
pazameter:
Flow
Average of Maximum of
Outfal] Frequency Daily Avp. (MGDI Daily Max (MGDI
001 Continuous 245.8 594.0
101 Intermittent 0.089 0.2680
002 Intemilttent 0.1387 0.985
Temperature (degrees F)
Outfall Daily Avg Daily Max
001 72 107
Effluent Chazacteristics
Outfall Parameter
001 Total Residual Chlorine'
Free Available Chlorine
101 pH (standard units)
Total Suspended Solids
Oil and Grease
Total Copper
Total Iron
Average of Maximum of
Dail~Ave Daily Max
N/A 0
0 0
6.3 minimum 8.7
4.6 mg/L 54 mg/L
4.2 mg/L 5.0 mg/L
no discharge of metal cleaning wastes
no discharge of metal cleaning wastes
Page 2
STATEMENT OF BASIS/I'ECHNICAL SUMMARY AND
EXECUTIVE DIItECTOR'S PRELIMINARY DECISION
TPDES Permit No, 01249
Average of Maximum of
Outfall Parameter Daily Avg Daily Max
002 pH 7.6 minimum 8.6
Total Suspended Solids 4.5 mg/L 7.0 mg/L
Oil & Grease 0.51 mg/L 1.30 mg/L
PROPOSED PERMIT CONDITIONS
The draft permit authorizes a dischazge ofonce-through cooling water and previously monitored effluents (low
volume waste sowces, and/or metal cleaning wastes via Outfall 101) via Outfa11001 at a daily average flow not to
exceed 594 million gallons per day and the dischazge of low volume waste sources and/or storm water via Outfall
002 on an continuous and flow variable basis.
Final effluent limitations aze established in th
Outfall Number Pollutant
001 Flow, MGD
Temperature, degrees F
Total Residual Chlorine
Free Available Chlorine
draft permit as follows:
Daily Average Daily Maximum
594 594
I10 116
N/A 247.81bs/day (0.2 mg/L)
82.5 lbs/day (0.2 mg/L) 2061bs/day (0.5 mg/L)
101 Flow, MGD Report R ort
Total Suspended Solids 30 mg/L 1 0 mg/L
Total Copper 0.5 mg/L 1.0 mg/L
Total Iron 1.0 mg/L 1.0 mg/L
Oil & Grease 15 mg/L 20 mg/L
pH no more than 9.0 standazd units nor less than 6.0
002 Flow, MGD Report Report
Total Suspended Solids 30 mg/L 100 mg/L
Chemical Oxygen Demand N/A 150 mg/L
Oil & Grease 15 mg/L 20 mg/L
PH no more than 9.0 standazd units nor less than 6.0
See Appendix A for a discussion of the effluent limits at each outfall. Biomonitoring requirements aze included in
the draft permit at Outfall 001. From August 19, 1999 to January 18, 2001, the permittee conducted four 7-day
chronic toxicity tests using both Ceriodaphnia dubia and Pimephales promelas with all tests passing lethal and
sublethalrequirements. During thesameperiod,thepermitteealsoconductedfow24-howacutetoxicitytestsusing
the same species with no toxicity.
SUMIv1ARY OF CHANGES FROM EXISTING PERMIT
1. Added an address to the location description of the permit at the request of the applicant.
2. Added a description of the discharge volume characteristics at Outfall 002 to clarify existing operations.
~No data was available in the PCS database for this outfall. These data represent the period from
October 1998 through October 1999.
Page 3
STATEMENT OF BASIS/TECHNICAL SUMMARY AND
EXECUTNE DIItECTOR'S PRELIMINARY DECISION
TPDES Permit Noy 01249
Changed the discharge route of Outfall 002 to reflect the actual operation of the discharge which enters
South Fork of Grapevine Creek or directly into Grapevine Creek.
4. Added mixing zone definitions for Outfa11002.
BASIS FOR PROPOSED DRAFT PERMIT
The following items were considered in developing the proposed permit draft:
1. Application submitted with letter dated Mazch 9, 2001 and additional information submitted with letters
dated April 9, 2001, Apri119, 2001, July 20, 2001, November 21, 2001, August 14, 2002, and January 27,
2003.
2. Existing permits: TPDES Permit No. 01249 issued October 5, 1999.
3. TCEQ Rules.
4. Texas Surface Water Quality Standazds - 30 TAC Sections 307.1-307.10, effective Apri130, 1997.
5. "Implementation of the Texas Natural Resource Conservation Commission Standazds via Permitting,"
Texas Natural Resource Conservation Commission, August 1995.
6. Memos from the Water Quality Standards Team and the Water Quality Assessment Team of the Water
Quality Assessment Section of the TCEQ.
7. "Guidance Document for Establishing Monitoring Frequencies for Domestic and Industrial Wastewater
Discharge Permits," TCEQ Document No. 98-001.000-OWR-WQ, May 1998.
8 . EPA Effluent Guidelines: 40 CFR 423 (NSPS, BAT, BCT, and BPT). Anew source determination was
performed and the discharge of once-through cooling water, low volume waste sources, metal cleaning
wastes, and storm water is not a new source as defined at 40 CFR Section 122.2.
9. Consistency with the Coastal Management Plan: N/A
PROCEDURES FOR FINAL DECISION
When an application is declared administratively complete, the Chief Clerk sends a letter to the applicant advising
the applicant to publish the Notice of Receipt of Application and Intent to Obtain Permit in the newspaper. In
addition, the Chief Clerk instructs the applicant to place a copy of the application in a public place for review and
copying in the county where the facility is or will be located. This application will be in a public place throughout
the comment period. The ChiefClerkalso mails this notice to any interested persons and, ifrequired, to landowners
identified in the permit application. This notice informs the public about the application, and provides that an
interested person may file comments on the application or request a contested case hearing or a public meeting.
Once a drag permit is completed, it is sent, along with the Executive Director's preliminary decision, as contained
in the technical summary or fact sheet, to the Chief Clerk. At that time, Notice of Application and Preliminary
Decision will be mailed to the same people and published in the same newspaper as the prior notice. This notice
sets a deadline for making public comments. The applicant must place a copy of the Executive Director's
preliminary decision and draft permit in the public place with the application. This notice sets a deadline for public
comment.
Any interested person mayrequest a public meeting on the application until the deadline for filingpublic comments.
A public meeting is intended for the taking of public comment, and is not a contested case proceeding. After the
public comment deadline, the Executive Director prepares a response to all significant public comments on the
application or the draft permit raised during the public comment period. The Chief Clerk then mails the Executive
Director's Response to Comments and Final Decision to people who have filed comments, requested a contested
case hearing, or requested to be on the mailing list. This notice provides that if a person is not satisfied with the
Page 4
STATEMENT OF BASIS/TECHNICAL SUNIMARY AND
EXECUTNE DIRECTOR'S PRELIMINARY DECISION
TPDES Permit Noy 01249
Executive Director's response and decision, they can request a contested case hearing or file a request to reconsider
the Executive Director's decision within 30 days after the notice is mailed.
The Executive Director will issue the permit unless a written hearing request or request for reconsideration is filed
within 30 days after the Executive Director's Response to Comments and Final Decision is mailed. If a hearing
request or request for reconsideration isfiled, the Executive Director will not issue the permit and will forward the
application and request to the TCEQ Commissioners for their consideration at a scheduled Commission meeting.
If a contested case hearing is held, it will be a legal proceeding similar to a civil trial in state district court.
If the Executive Director calls a public meeting or the Commission grants a contested case hearing as described
above, the Commission will give notice of the date, time, and place of the meeting or hearing. If a hearing request
or request for reconsideration is made, the Commission will consider all public comments in malting its decision
and shall either adopt the Executive Director's response to public comments or prepare its own response.
For additional information about this application contact Kelly Holligan at (512) 239-2369
7~23~03
Kelly lligan Date
Page 5
STATEMENT OF BASIS/TECIINICAL SUMMARY AND
EXECUTIVE DIRECTOR'S PRELINIINARY DECISION
TPDES Permit No, 01249
APPENDIX A
Outfa11001
The once-through cooling water discharged via Outfa11001 is subject to BPT limitations at 40 CFR §423.12(b)(6)
& (8) and BAT limitations at 40 CFR§423.13(b)(1) & (2). There are no BCT ]imitations currently established at
40 CFR Part 423.
40 CFR §423.12(b)(6) & (8)
The applicant is allowed to discharge on average 594 MGD. 40 CFR §423.12(b)(8) specifies that free available
chlorine shall not be dischazged more than two hows in any one day. Applying the BPT limitations at 40 CFR
§423.12(b)(6), the following mass-based equivalent limitations were calculated using the following formula:
Mass Loading = (Flow, MGD)(Concentration, mg/L)(1 day/24hows)(2hrs chlorination/day)(3 Units)(8.345)
Free Available Chlorine Limitations:
Daily Average = (594 MGD)(0.2 mg/L)(1/24)(2)(8.345)(3 Units) = 247.8 Ibs/day
Daily Maximum = (594 MGD)(0.5 mg/L)(1/24)(2)(8.345)(3 Units) = 619.61bs/day
The proposed permit also includes concentration limits for free available chlorine which is consistent with the
existing TPDES permit.
40 CFR§423.13(b)(1)
40 CFR §423.13(b)(1) specifies that total residual chlorine shall not be discharged more than two hows in any one
day. Applying the BAT limitations at 40 CFR §423.13(b)(1), the following mass-based equivalent limitation was
calculated using the equation above:
Total Residual Chlorine Limitation:
Daily Maximum = (594 MGD)(0.2 mg/L)(1/24)(2)(3 Units)(8.345) = 247.81bs/day
The proposed permit also includes concentration limits for free available chlorine which is consistent with the
existing TPDES permit.
Total Dissolved Solids ('I'DS), Sulfates, and Chlorides
The effluent data submitted with the application showed total dissolved solids and sulfate concentrations that may
present a potential concern when compared to the segment criteria. The TCEQ met with the permttee to discuss
this issue, and the permiee submitted additional and historical data regazding these parameters. After review of
the additional data, the Water Quality Standards Team determined that no degradation of high quality water is
expected and that existing uses will be maintained and protected.
Outfalls 101 and 002
The discharge of low volume wastes is subject to BPT limitations at 40 CFR § 423.12(b)(3). There are no BAT
or BCT limitations for low volume wastes. This section specifies limits for total suspended solids and oil and
grease. 40 CFR § 423(b)(11) allows the permitting authority to specify mass-based limits or concentration limits
for these pollutants. The proposed permit contains concentrations limits which is consistent with the existing
Page 6
STATEMENT OF BASISl1'ECHNICAL SUMMARY AND
EXECUTIVE DIItECTOR'S PRELIMINARY DECISION
TPDES Pemilt No. 01249
TPDES permit. The proposed limits aze:
Total Suspended Solids (Daily Average) = 30 mg/L
Total Suspended Solids (Daily Maximum) = 100 mg/L
Oil and Grease (Daily Average) = 15 mg/L
Oil and Grease (Daily Maximum) = 20 mg/L
Outfall 101
The discharge of metal cleaning wastes from this outfall is subject to BPT limitations at 40 CFR 423.12(b)(5) and
BAT limitations at 40 CFR 423.13(e). The proposed permit contains concentrations limits which is consistent with
the existing TPDES permit. The proposed limits aze:
Total Copper (Daily Average) = 0.5 mg/L (based on 30 TAC 319.23)
Total Copper (Daily Maximum) = 1.0 mg/L
Total Iron (Daily Average) = 1.0 mg/L
Total Iron (Daily Maximum) = 1.0 mg/L
Outtfall 002
Effluent limits for chemical oxygen demand, total suspended solids, oil and grease, and pH were tamed forward
from the existing TPDES permits. There aze no technology-based requirements for the discharge of storm water
in 40 CFR Part 423.
Chemical Oxygen Demand (Daily Average) = N/A
Chemical Oxygen Demand (Daily Maximum) = 150 mg/L
General Permit Requirements
The pH limitations of 6.0-9.0 S.U. as specified at 40 CFR §423.12(b)(1) were applied to all outfalls except Outfall
001 consistent with TCEQ practice. Outfa11001 is exempted because of the once-through cooling water discharge
is exempted from pH requirements in 40 CFR 423.
The provision that there shall be no dischazge ofpo]ychlorinated biphenyl transformer fluid as required in 40 CFR
§423.12(b)(2)-BPT and §423.13(a) was required in the proposed permit.
Page 7