ML20004C824

Responds to 810225 Ltr Re Emergency Procedures & Training for Station Blackout Events.Upon Loss of Reserve Auxiliary Transformer,Power Will Be Quickly Restored by Either Emergency Reserve Auxiliary Transformer or Diesel Generator

ML20004C824
Person / Time
Site:	Clinton
Issue date:	06/01/1981
From:	Wuller G ILLINOIS POWER CO.
To:	Eisenhut D Office of Nuclear Reactor Regulation
References
L30-81(06-01)-L, U-0240, U-240, NUDOCS 8106050403
Download: ML20004C824 (3)

Text

_ _

U-0240

/LLINDIS POWER COMPANY L30.gt(os.ot) L 500 SOUTH 27TH STREET, DECATUR, ILLINOIS 62525 June 1, 1981 r

/Wfit.hk11.

Cl ( 0.lC) ?)as jut; O 1 '981

• C Mr. Darrell G. Eisenhut, Director 3 u 4

Division of Licensing h\ .s. ewi ewo".Q}

^

Office of Nuclear Reactor Regulation #

U. S. Nuclear Regulatory Commission Washington, D. C. 20555

/ Ni M*

Reference:

Your letter of 2/25/81, subject: Emergency Procedures and Training for Station Blackout Events (Generic Letter 81-04)

Dear Mr. E:

.senhut:

Clinton Power Station Units 1 & 2 Docket Nos. 50-461 and 50-462 This is in response to the referenced letter. A review was conducted of the existing Clinton procedu.es and training require-ments for a station blackout and the following comments are offered:

a) The Level Control Emergency Guidelines procedure will adequately cover action necessary for monitoring reactor level and decay heat removal with only DC power avail-able. The Reactor Core Isolation Cooling (RCIC) and Automatic Depressurization System (ADS) are designed to operate without support from auxiliary systems such as cooling water or ventilation.

, b) The estimated time available to restore AC power cannot be determined without a specific scenario.

! c) The action for restoring AC power in the event of a l

loss of the grid will be directed by the Supervisor -

Electric Suppl / as per the Electric Emergency Plan of Operation.

d) The actions for restoring offsite AC power when its loss is due to postulated onsite equipment failure was examinea for the loss of the Reserve Auxiliary.

Transformer (RAT) and the Emergency Re<3erve Auxiliary Transformer.(ERAT). Upon a loss of the RAT, power will be quickly restored by either the ERAT or diesel 300j S

l 10 8106050 O lO - -~ . _ __ _-

L s s' ~ . Y U-0240-c Mr...Darrell G.'Eisenhut- L30-81(06-01)-L

[- Page 2 June!1,11981=

o generators. Power to the non-lE buses can be res'tored

. by manually disconnecting the main' generator . from . the ' '

generator bus and-back feeding throughithe Unit' z

' Auxiliary Transformers. Permanentfrestoration of power to.the11E buses and-startup power to the.non-lE buses will be accomplished.upon removal of the' failed

RAT and. installation of the spare 1 RAT.

l Upon a loss-of the ERATi power will be restored to;the: .

i class lE buses by the: RAT or diesel generators. .The

' ERAT.will be ' replaced by a spare transformer :from Illinois' Power Company's Electric Plant spare transformer ,

pool.

e) The action-necessary to restore emergency onsite AC. power E

will be to restart the diesel. generators. The diesel generators are designed to start without' dependence on external AC power.. The starting. systems'are designed . '

for five starts on their own starting air system. ,

4 Division III additionally has a diesel-driven air-compressor to supply its starting system.

Upon loss of AC power all 4-KV motor loads are shed on

Divisions I and II. buses. Division III loads are not shed. After each diesel generator reaches rated.fre-quency and voltage,.its breaker shuts and 4-KV motor-loads are automatically sequentially started on Division I'and II. Division III loads pick up with the diesel.

f) D.C. emergency lighting.will beginstalled inLthe main control room and in areas required forqsafe shutdown of' the plant.such as ECCS'and RCIC equipment rooms and-essential switchgear areas.

Emergency lighting automatically switches on upon a loss; of AC power to normal station lighting.

The adequacy of emergency lighting will be evaluated during the Preoperational. Phase of the startup of Clinton Power Station. .

l

[ g) Current-Off Normal procedures will be revised to includo

~

[ restoration of power to buses'following a station: black-

[ out condition. .Special concerns involving restoration ,

l of power will be addressed.'

_ , . --_.,,___,L.,_._.,_...,,-...-_.___..._,-.,.-_.__ . . . _ . _ - _ . . . _ - . _ _ _ _ , _ . , . . -

g.

U-0240 Mr. Darrell G. Eisenhut- L30- 81(06-01) -L Page 3 June 1, 1981 The training department will revise the annual requalification training program prior to initial licensing to include. training in loss of all AC power.

Siricerely,

/ dsE.%f6 G. E. Wuller Supervisor-Licensing Nuclear Station Engineering GEW:ks cc: C. I. Grimes, NRC Proj ect Manager H. H. Livermore, NRC Resident Inspector s

)

t l

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