ILLINOIS ENVIRONMENTAL PROTECTION AGENCY' E
CLERK'S
C E 1
OFFICEV
E D
November 8, 2006
DEC 0 5 200E
STATE OF ILLINOIS
Pollution Control Board
Exelon Generation Company, LLC
)
Dresden Nuclear Generation Station
)
Petitioner,
)
v.
)
IEPA - 07-Cl
(Provisional Variance-Water)
ILLINOIS ENVIRONMENTAL
)
PROTECTION AGENCY,
)
Respondent .
)
Re:
Provisional Variance From Special Conditions 4A, 4D, and 4G
of NPDES Permit IL00022241
Dear Mr. Wozniak :
The Illinois Environmental Protection Agency (Agency) has completed its technical
review of the attached provisional variance request (Attachment A) submitted by Dresden
Nuclear Generation Station (Dresden Station) on November 6, 2006
. Dresden Station is
requesting a provisional variance for a six-day period, beginning November 17, 2006,
through November 22, 2006, in order to repair a Lift Station Automatic Bus Transfer
(ABT) switch
. This switch was damaged by a lighting strike on July 27, 2006
. Dresden
Station submitted a provisional variance request on October 10, 2006, requesting the
same relief for a six-day period beginning November 7, 2006, through November 12,
2006, which the Agency granted on October 23, 2006 (IEPA - 07-05 (Provisional
Variance-Water))
.
Since that time, however, Unit 2 has developed an issue internal to its condenser, and
performing the lift station repairs between November 7, 2006, and November 12, 2006,
would impose additional operating loads on Unit 2 equipment
. Dresden Station therefore
submitted its current request
. Based on its review, the Agency GRANTS a provisional
variance subject to the specific conditions set forth below
. This provisional variance
supercedes the October 23, 2006 provisional variance .
' NPDES Permit No
. IL0002224 expired on October 31, 2005 . Because the permittee timely filed for
renewal, however, the permit continues in full force and effect
.
Background
Dresden Station is a nuclear-fueled steam electric generating facility located at the
confluence of the Des Plaines and Kankakee Rivers near Morris, Illinois, at River Mile
272.3 . The two boiling reactors have a maximum generating capacity of 1824 megawatts
electric. Circulating water used to, cool and condense the steam from the generating
process is discharged to a 1275 acre cooling pond .
Dresden Station normally operates in a closed cycle mode from October 1 through June
14 (about 8 '/2 months) . In the closed cycle mode, approximately 1,000,000 gallons per
minute (gpm) of cooling water is drawn into the station's cribhouse intake structure,
passes through the station's heat exchangers, and discharges to a hot canal that routes the
water approximately two miles to the lift station
.
The lift station lifts the 1,000,000 gpm
of the cooling water approximately 20 feet from the hot canal to the aboveground cooling
pond. The cooling water routes around the cooling pond and spills over a spillway into
the cold canal, which routes the cooling water approximately two miles back to the
station . The flow regulating gates direct the majority of the cooling water back to the
cribhouse intake structure through a return canal. These gates divert approximately 5
percent or 50,000 gpm of the cooling water flow (limited to 72 million gallons per day
(MGD)) to the Illinois River via Outfall 002 . The Kankakee River provides makeup flow
through a 1/4-mile intake canal . The volume of makeup flow is equal to the blowdown
flow and water lost to evaporation .
From June 15 to September 30 of each year (about 3 V2 months), Dresden is allowed to
operate in an indirect open cycle mode . In this mode, approximately 1,000,000 gpm of
cooling water is drawn into the station's cribhouse intake structure from the Kankakee
River via the intake canal . This cooling water passes through Dresden's heat exchangers
and discharges to the hot canal that routes the water approximately two miles to the lift
station . The lift station lifts the cooling water approximately 20 feet from the hot canal to
the above ground cooling pond . The cooling water routes around the cooling pond and
spills over the spillway into the cold canal, which routes the cooling water approximately
two miles back to the station . The flow regulating gates divert all the cooling water flow
(approximately 1,000,000 gpm) to the Illinois River via Outfall 002 . The Illinois
Pollution Control Board approved this operational
scheme and the related alternate
thermal standards on July 9, 1981 .
The lift station is equipped with six lift pumps, each with a 167,000-gpm capacity
. The
pumps provide motive force that allows the cooling water to flow around the cooling
pond, over the spillway, through the cold canal to the flow regulating gates.
Relief Requested
Dresden Station seeks a variance from Special Conditions 4A, 4D,and 4G of NPDES
Permit IL0002224 (Attachment B). Special Condition 4A requires that the maximum
temperature rise above natural temperature must not exceed 5° F at the edge of the
mixing zone, in accordance with Section 302 .211(d) of Subtitle C (35 Ill . Adm. Code
Sec. 302 .211(d)) when operating in closed cycle mode
. Special Condition 4D requires
that Dresden operate in the closed cycle mode during the period October 1 to June 14
.
Special Condition 4G allows Dresden to bypass the cooling pond only when both
generating units are out of service
. A variance from these conditions will allow Dresden
Station to operate in open cycle mode (i.e .,
bypass the cooling pond) .
Dresden Station requests that the provisional variance begin on Friday, November 17,
2006, and continue through Wednesday, November 22, 2006, during which time Dresden
Station can operate in open cycle mode for 144 hours
. During this period, Dresden will
repair the existing Lift Station ABT switch and make other related electrical repairs . This
activity will restore the Lift Station electrical equipment redundancy and reliability
.
To minimize the thermal discharge from the plant, the provisional variance period
coincides with a scheduled refueling outage of one of the facilities two units
.
Agency Determinations
The Agency has reviewed the requested provisional variance and has concluded the
following:
No significant environmental impact will occur as a result of this
provisional variance . Dresden Station will closely monitor the
environmental impact from the requested relief and will immediately
notify the Agency of any significant impact along with actions taken to
remedy the problem ;
2.
No reasonable alternatives appear available ;
3 .
No public water supplies will be affected
;
4 .
No federal regulations will preclude the granting of this request ; and
5 .
Dresden Station will face an atbitrary and unreasonable hardship if the
request is not granted
.
Conditions
The Agency hereby GRANTS the Dresden Station a provisional variance from Special
Conditions 4A, 4D, and 4G of NPDES Permit IL0002224, subject to the following
conditions
:
A.
The provisional variance shall begin on Friday, November 17, 2006, and
continue through Wednesday, November 22, 2006, during which time
Dresden Station can operate in open cycle mode for 144 hours
;
B .
Dresden Station shall comply with the General Use thermal discharge
standards outlined in its NPDES permit's Special Condition 4B during
the variance period;
C .
Dresden Station shall continuously monitor intake, discharge and Dresden
Lock
and Dam temperatures so it can document environmental
conditions during the variance period . Dresden Station shall also
conduct visual inspections on a daily basis in the vicinity of the intake
and the discharge, so it can document the effects of any
increased
thermal output to the river
. Dresden Station shall notify the Agency if
it identifies any unusual or unexpected environmental impact;
D.
Dresden Station shall conduct additional biological monitoring
of the
resident fish community, which shall consist of fish sampling during and
after the variance period . Dresden Station shall conduct two surveys at
eight locations using electrofishing, and two surveys at seven locations
using seining
. Dresden Station shall also monitor the physical conditions
by compiling temperature and oxygen profiles in all appropriate survey
locations;
E.
Dresden Station shall conduct additional biological monitoring of the
benthos community, which shall consist of macro invertebrate sampling
just prior to and just after the variance period
. These two surveys shall be
performed at six locations using a Ponar grab sampler ;
F .
Dresden Station shall notify Roger Callaway of the Agency by telephone
at 217/782-9720 when the need to operate in direct open mode begins, and
again when the 144 hours are utilized . Written confirmation of each
notice shall be sent within five days to the following address
:
Illinois Environmental Protection Agency
Bureau of Water - Water Pollution Control
Attention: Roger Callaway
1021 North Grand Avenue East, MC #19
Springfield, Illinois 62794-9276
G.
Dresden Station shall sign
a certificate of acceptance of this provisional
variance and forward that certificate to Roger Callaway at the address
indicated above within one day of the date of this order
. The certification
should take the following form:
I (We) ,
hereby accept and agree to be bound by all terms
and conditions of the provisional variance granted by the Agency in
dated
Petitioner
Authorized Agent
Title
Date
Dresden Station shall continue to monitor and maintain compliance with all other
parameters and conditions specified in its NPDES Permit No
. 1L0002224 .
Conclusion
The Agency grants this provisional variance in accordance with its authority contained in
Sections 35(b), 36 (c),
and 37(b) of the Illinois Environmental Protection Act (415 ILCS
5/35(b), 36(c), and 37(b) (2004)
. The decision to grant this provisional variance is not
intended to address compliance with any other applicable laws or regulations
.
Robert A. Messina
Chief Legal Counsel
c :
Marcia Willhite
Roger Callaway
Vera Herst
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November 6, 2006
DBWLTR 06-044
VIA AIRBORNE EXPRESS
Mr . Mike Garretson
Manager, Compliance Assurance Section 419
Illinois Environmental Protection Agency
Bureau of Water
1021 North Grand Avenue East
P. 0
. Box 19276
Springfield, Illinois 62794-9276
Subject :
Dresden Nuclear Generation Station
NPDES Permit No . IL0002224
Provisional Variance -
Request for Lift Station ABT Repairs
Dear Mr . Garretson :
On October 23, 2006, EPA granted Provisional Variance 07-05 allowing Dresden to operate in direct open
cycle mode for 6 days (144 hours) in order to implement repairs to the cooling pond Lift Station
. The
Provisional Variance is scheduled to start on November 7'" and continue through November 12`
h .
Due to
emergent operational issues, which arose following the issuance of the Provisional Variance order, Dresden
must delay the Lift Station outage (and repairs) for 10 days
.
Dresden intended to perform the Lift Station repairs during the current refueling outage on Unit 3
. However,
Unit 2 has developed an issue internal to its condenser
. Performing the Lift Station work as planned would
impose additional operating loads on Unit 2 equipment, necessitating a delay
. Therefore, Dresden
respectfully requests that EPA issue a revised Provisional Variance Order indicating that the Provisional
Variance period will instead start on November 17
1h
and continue (for the same 6-day duration) through
November 22"d .
Dresden has begun the pre-variance aquatic monitoring studies
. Exelon Corporate and
Dresden personnel presented this issue to EPA personnel by telephone conference on Friday, November
3, 2006 and Monday, November 6, 2006 .
All other provisions of the Provisional Variance request remain the same
. Please review this request and
revise the Order at your earliest convenience .
Should you require any further information in order to expedite the processing of this request or have any
questions, please contact Ed Rowley of my staff at 815-416-3287
.
incerely,
-Aft
David B
. Wozniak
Dresden Station Plant Manager
CC:
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. Papanic
B . Rybak
J
. Schmitz
S . Neal
J . Strmec
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