ML19332F576

Proposed Tech Spec Section 3.7, Auxiliary Electrical Power.

ML19332F576
Person / Time
Site:	Oyster Creek
Issue date:	12/04/1989
From:	GENERAL PUBLIC UTILITIES CORP.
To:
Shared Package
ML19332F573	List: ML19332F572 ML19332F575 ML19332F576
References
NUDOCS 8912150171
Download: ML19332F576 (3)

Text

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• . 3.7 AUXILIARY ELECTRICAL POWER Aeolicabilitys Applies to the operating status of the auxiliary electrical power supply.

Obioetive: To assure the operability of the auxiliary electrical power supply.

Specification: A. The reactor shall not be made critical unless all of the following requirements are satisfied:

1. The following buses or panels energized.

a. 4160 volt buses IC and ID in the turbine building switchgear room.

b. 460 volt buses 1A2, 1B2, lA21, 1B21 vital MCC 1A2 and IB2 in the reacter building switchgear room:

1A3 and IB3 at tl.e intake structure; 1A21A, ID22A, 1A212, and 1B218 and vital MCC 1AP2 on 23'6" clavation in the teactor building; 1A24 and 1B24 at the stack.

c. 208/120 volt panels 3, 4, 4A, 4B, 4C and VACP-1 in the reactor building switchgear room.

d. 120 volt protection panel 1 and 2 .in the cable room,

e. 125 volt DC distribution centera C and B, and panel D, Panel DC-F, isolation valve metor control center DC-1 and 125V DC motor control center DC-2.

f. 24 volt D.C. power panels A and B in the cable room.

2. One 230 KV line is fully operational and switch gear and both startup transformers are energized to carry power to the station 4160 volt AC buses and carry power to or away from the plant.

! 3. An additional source of power consisting of one of the l following is in service connected to feed the l

appropriate plant 4160 V bus or buses:

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a. A second 230 KV line fully operational.

b. One 34.5 KV line fully operational.

4. Station batteries B and C and an associated battery changer are operable. Switchgear control power for l 4160 volt bus ID and 460 volt buses 1B2 and 183 are provided by battery B. Switchgear control power for 4160 volt bus IC and 460 volt buses 1A2 and 1A3 are provided by battery C.

5. Bus tie breakers ED and EC are in the open position.

B. The reactor shall be placed in the cold shutdown position if the availability of power falls below that required by Specification A above, except that

1. The reactor may remain in operation for a period OYSTER CREEK 3.7-1 Amendment No.: 44, 55, 80, 119 5751f/TSCR182 8912150171 891204 PDR ADOCK 05000219 P PNU

t L .

'. . n:t to ex;eed 7 C:y] in cny 30 dry period if a startup transformer is out of service. None of the engineered safety feature equipment fed by the remaining transformer may be out of service. g L 2. The reactor may remain in operation for a period not to exceed 7 days if 125 VDC Motor Control Center DC-2 is out of service, provided the l requirements of Specification 3.8 are met.

C. Standby Diesel Generators

1. The reactor shall not be made critical unless both diesel generators are operable and capable of feeding their designated 4160 volt buses.

2. If one diesel generator becomes inoperable during power operation, repairs shall be initiated '

immediately and the other diesel shall be operated at least one hour every 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> at greater than 20% rated power until repairs are completed. The  ;

reactor may remain in operation for a period I;ot to exceed 7 days in any 30-day period if a diesel generator is out of service. During the repair ,

period none of the angineered safety features normally fed by the operational diesel generator -

ray be out. of service or the reactor shal.1 be placed in the cold shutdown condition.

3. If both diesel generators become inoperable during power operation, the reactor shall be placed in the cold shutdown condition.

4 For the diesel generators to be considered operable there shall be a minimum of 14,000 gallone of diesel fuel in the standby diesel generator fuel tank.

Bases: The general objective is to assure an adequate supply of power with at least one active and one standby source of power available for operation of equipment required for a safe plant shutdown, to maintain the plant in a safe shutdown condition and L to operate the required engineered safety feature equipment ,

I following an accident.

l AC power for shutdown and operation of engineered safety feature equipment can be provided by any of four active (two 230 KV and l~ two 34.5 KV lines) and either of two standby (two diesel l generators) sources of power. Normally all six sources are y available. However, to provide for maintenance and repair of equipment and still have redundancy of power sources the requirement of one active and one standby source of power was l

established. The plant's main generator is not given credit as a l source since it is not available during shutdown.

l OYSTER CREEK 3.7-2 Amendment No.: 44, 55, 99, 119 5751f/TSCR182

i~ .I I

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.- * . The plcnt 125V DC Syctem c nristo cf three battcrico cnd conociettd distribution system. Batteries B and C are designated as the safety related subsystems while battery A is designated as a non-safety related I subsystem. Safety related loads are supplied by batteries B and C, each l with two associated full capacity chargers. One charger on each battery j is in service at all times with the second charger available in the event ]

of charger failure. These chargers are active sources and supply the l normal 125V DC requirements with the batteries and standby sources. (1) l I

In applying the minimum requirement of one active and one standby source  !

of AC power, since both 230 KV lines are on the same set of towers, ,

either one or both 230 KV lines are considered as a single active source.  !

The probability analysis in Appendix "L" of the FDSAR was based on one diesel and shows that even with only one diesel the probability of '

requiring engineered safety features at the same time as the second diesel fails is quite small. This analysis used information on peaking diesels when synchronization was required which is not the case for oyster Creek. Also the daily test of t'ne second diesel when one is temporarily out of service tends to hoprove the reliability as does the fact t. hat synchronization is nce required.

As indicated in Amendment 18 to the Licensing Application, there are numerous sources of diesel fuel which can be obtcined within 6 to 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> and 4:ht heating boiler fuel in a 75,000 gallon tank on the site could cleo be used. As indicated in Amendment 32 of the Licensing Applicatinn end irar:1uding the Secvrity System loads, the load rnquirement for the loss of offsite power sould require 12.410 gallons for a three day supply. For the case of loco of offsito power plus lone-of-coolant plus bus: failure 9790 galler.s would bo required for s three day supply.

In the case of loss of offsite power plus loss-of-coolant with both diesel generators starting the load requirements (all equipment operating) shown there would not be three days' supply. However, not all ,

of this load is required for three days and, af ter evaluation of the conditions, loads not required on the diesel will be curtailed. It is reasonable to expect that within 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> conditions can be evaluated and the following loads curtailed:

1. One Core Spray Pump

2. One Core Spray Booster Pump

3. One Control Rod Drive Pump

4. One Containment Spray Pump

5. One Emergency Service Water Pump l

l With these pieces of equipment taken off at 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> after the incident it would require a total consumption of 12,840 gallons for a three day supply. Therefore, a minimum technical specification requirement of 14,000 gallons of diesel fuel in the standby diesel generator fuel tank will exceed the engineered safety features operational requirement after an accident by approximately 9%.

References:

(1) Letter, Ivan R. Finfrock, Jr. to the Director of Nuclear Reactor Regulation dated April 14, 1978.

l l

OYSTER CREEK 3.7-3 Amendment No.: 55, 60, 99, 119 l

5751f/TSCR182 l

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