ML20079S228

Forwards Info on SER Open Item 10 Re Safe Shutdown Analysis & Standby Shutdown Sys Confirming safety-related Batteries in Station Control Complex Not Required for Hot Standby Condition Per App R to 10CFR50

ML20079S228
Person / Time
Site:	Catawba
Issue date:	07/05/1983
From:	Tucker H DUKE POWER CO.
To:	Adensam E, Harold Denton Office of Nuclear Reactor Regulation
References
NUDOCS 8307110383
Download: ML20079S228 (34)

Text

F-4 DUKE POWER COMPANY P.O. HOX 33180 CHAMLOTTE, N.C. 28242 HALD. TUCKER Teternose vice raesionwr (704) 37MNM

- *= -= ==' July 5, 1983 .

Mr. Harold R. Denton, Director Office of Nuclear Reactor Regulation U. S. Nuclear Regulatory Commission Washington, D. C. 20555 Attdntion: Ms. E. G. Adensam, Chief y .

Licensing Branch No. 4 Re: Catawba Nuclear Station Docket Nos. 50-413 and 50-414

Dear Mr. Denton:

Section 9.5.1 of the Catawba Safety Evaluation Report identifies the Safe ,

Shutdown Analysis, Description of Standby Shutdown System, Design of Bulk Gas System and Divisional Separation in Battery Rooms as Open Item 10. The Bulk Gas System was addressed in my letter of April 14, 1983. The remaining three issues are discussed in the following attachments:

Attachment 1 - Review of Cable Separation in Catawba Unit 1 Reactor Building Attachment 2 - Discussion of Associated Circuits Attachment 3 - Information in Support of the Catawba Standby Shutdoun System , ,

Attachments 1 and 2 pertain to the Safe Shutdown Analysis; Attachment 3 pertains to the Standby Sh*utdown System.

e Information in this submit.tal confirms that the safety related batteries in the station control complex are not required for hot standby condition. Therefore, the current arrangement complies with BTP CMEB 9.5.1, Item C.S.b(2) and installa-tion of sprinklers in Fire Areas 9 and 10 is not required.

Very truly yours, 5 lg(f Hal B. Tucker ROS/php Attachments (3)

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8307110383 830705 l

PDR ADOCK 05000413 E PDR

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t Mr. Harol,d R. Denton, Director July 5, 1983 Page 2 -

cc: Mr. James P. O'Reilly, Regional Administrator U.~S. Nuclear Regulatory Commission Region II

- 101 Marietta Street, NW, Suite 2900 **

Atlanta, Georgia 30303 .

Resident Inspector fatawba Nuclear Station s' Mr. Robert Guild, Esq.

Attorney-at-Law ^

P. O. Box 12097 '

Charleston, South Carolina 29412 Palmetto Alliance- ,

2135 Devine Street y Columbia, South Carolina 29205 Mr. Jesse L. Riley Carolina Environmental Study Group -

854 Henley Place Charlotte, North Carolina 28207 s.

Mr. Henry A. Presler, Chairman Charlotte-Mecklenburg Environmental Coalition 943 Henley Place , y Charlotte, North Carolina 28207 Mr. Jim (Behn Gage Babcock and Associates 135 Addison Avenue * ' "

Elmhbrst, Illinois 60126

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, ATTACHMENT 1 I. PURPOSE This attachment is to document the assumptions, procedures and results of a detailed evaluation for Unit 1 Catawba Appendix R study.

II. CRITERIA

- a The criteria for this study is as stated in Appendix R. .

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Fire protection features shall be provided for structures, systems and components important to safe shutdown. These features shall be capable of limiting fire damage so that:

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One train of systems necessary to achieve and maintain hot shutdowr.

conditions from either the control room or emergency control station (s) is free of fire damage; and systems nec@ssary to achieve and maintain

• cold shutdown from either the control room or emergency control station (s) can be repaired and cold shutdown reached and maintained within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />.

1. Inside containment, one of the following fire protection means shall be provided. ,

'A. Separation of cables and equipment and associated non-safety circuits of redundant trains by a distance of more than 20 feet with no intervening combustibles or fire hazards; or B. Installation of fire detectors and an automatic fire suppression

. system in the fire area; or C. Separation of cables and equipment and associated non-s1fety circuits of redundant trains by a noncombustible radiant energy shield.

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, 2. Outside containment, one of the fo'llowir.g means shall be provided.

l A. Separation of cables and equipment and associated non-safety

! circuits of redundant trains by a fire barrier *having a three hour rating; or ,

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. B. Separation of cables and eqssipment and associated non-

.. safety circuits of redundant trains by a distance of more than 20 feet with no intervening cembustibles or, fire ha za rd s . In addition, fire detectors and an automatic fire suppressJon system shall be installed in the fire area; or C. Enclosure of cable and equipment and associated n6n-safety circuits of one redundant train with a fire barrier having a .1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> ra ting. In addition, fire detectors and an auto-matic fire suppression system shall be installed in the fire area.

III. ASSUMPTIONS -

1. Only the equipment required for a hot shutdown need to be considered, since at this state the containment can be eritered and necessary measures taken with damaged controls to bring the plant to a cold shutdown.

2. 'The equipment associated with the Standby Shutdown Facility, SSF, will be . sufficient to bripg the plant to a hot shutdown condition.

3. Armored cable without a PVC jack'et is a non fire propagating material and armored cable with a PVC jacket is a fire propagating material.

4. Because of the limited' amount of combustibles inside containment, the postulated fires duld be from transient combustibles and expected not to spread beyond the area of origin. This means credit can be taken:

a) for devices / cables inside containment which are not in the area of the postulated fire and, b) for devices / cables outside containment.

5. The annulus is considered part of containment. .

6. Inner Containment is considered the area inside the Con,tainment Vessel.

7. Shorts within control cables were considered for possible spurious valve operation.

I V .'

PROCEDURES (Inner Containment)

• 9 The following procedures were followed to determine to.what degree Appendix R was met within Inner Containment.

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1. Locations of areas where fires might occur were identi, fled ,

These included grates, platforms and floor areas where combustibles might be placed.

(However, due to the existing separation between the SSF and alternate devices / cables, the presence of the grates did not have any affect on the meeting of Appendix R '

requiremegts).

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2. Identified and located SSF related devices and cables.

, 3. Where SSF related devices and cables were within a postulated fire area it was determined if an alternate device existed that would provide the same function and a) not have cables in the same area as the postulated fire, or b) be located outside containment.

4. Cable separation was determined by a computer cable routing drawing study.

5. When direct alternatives did not exist, other means of providing the SSF function were identified. This procedure was accomplished by the following:

a) A study was conducted to determine the impact of the SSF function being inoperable during an Appendix R event.

b) If the impact would be negligible, then it was documented.

c) If the loss of a particular SSF function would be severe, and a direct alternate did not exist, a different approach of achieving the same function was identified. For exanggl e, ,

referer.ce section V.3.

V. RESULTS (Inner Containment)

.- 1. The following section contains SSF devices which have alternates outside containment.

a) The Nuclear Sampling System Isolation valves INM3A and INM6A have as their alternate INM78. Also Nuclear Sampling System Isolation valves INH 22A and NM25A have as their .

al terna te INM26B.

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P b) The steam generator secondary side isolation valves add their alternates are listed below. Please reference figure I for a typical flow path.

SSF Valve Al terna tes

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IBB8A ,

IBB10B and 1B81478 1BB19A 188218 and 1881500 ,

IBB56A 18857B and 188148B 1BB60A 188618 and 1881498 c) The Reactor Coolant Pump Seal Water Return Isolation valve INV89A has as its alternate INV918. -

2. This section consists of solenoid controlled valves that are de-4 energized to provide the SSF function. This de-energization is accomplished by disconnecting the power to the solenoids and limit switches via disengaging connectors (mounted in two separate enclosures) in the train "A" 4KV Essential Switchgear Room, and installing shorting pins in the connectors.T!.is measure eliminates the possibility of spurious valve operation.

a) Pressurizer Power Operated Relief Valves (Isolation) INC328, ~

1NC34A, and 1NC368.

b) Reactor Coolant /CVCS Train A Isolat,fon valve INVI A. .

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c) Reactor Coolant /CVCS Train B Isolation valve 1NV1228.

I d) Reactor Coolant / Pressurizer Spray Isolation valves INC27 -

and 1NC29.

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3. The following valves are associated with the Standby Hakeup Pump and are not required, since a fire inside containment will not affect equipment outside containment, where other means of charging are available.% (Desides the normal flow path for make-

! up, charging can be accomplished by alignint} a centrifugal or +

the reciprocating charging pump through the boron injection flow path to the reactor coolant cold legs). These valves isolate to compensate for the low flow capability of the Standby Makeup Pump.

a) Standby Makeup Pump / Reactor Coolant Pump Seal Water Isolation valve, INV877.

b) Standby Makeup Pump Drain Isolation valve, INV876.

c) Reactor Coolant Syste,m (Head Vent) valves, INC250A and 1NC253A.

4. The Residual Heat Removal System (ND) Isolation valves IND2A and IND37A, have as their alternates IND1B and IND36B respectively. These valves are normally closed and must remain closed to protect the lower pressure ND piping from the higher pressures in the primary loop. The isolation valves and their alternates are both located inside containment, however, Appendix R separation exist. (Cable 1*N0599, associa ted with iflD37A, provides a permissive interlock for valves INIl368,1NiiG48, and INS 388. Therefore an internal short, due to a postulated fire, would not result in spurious operation of IND37A. Thus the routing of 1*N0599 within the 20 foot separation of the train B alternate valve and associated cables is insignificant. There will be administrative procedury implemented for cable 1*ND599, to- prevent the violation of Appendix R in the future.) Reference Table I for separation distances.

5. The SSF power cable to the Pressurizer Heater is 11.E607. If the SSF Pressurizer lleater or cable ILE607 is damaged, due to a fire, the plant could be <taken to hot shutdown and maintained in that condition i

, until a cold shutdown could be achieved. -

Westinghouse has performed calculations demonstrating that heat '

losses from the pressurizer are low enough to maintain RCS pressuriza-7 tion for natural circulation for at least- four hours. (They assumed a loss of offsite power). .During this time cooldown towards ND initiation could be in progress or virtually complete. (Cooling the RCS below hot statndby conditions extends the time between loss of heaters and loss of sub-cool ing) .

6. The cables associated with the incore t'hermocou*ples, for temperature monitoring, will be separated. To comply with Appendix a criteria.

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Ta'ble 2 consists of a complete list of SSF. cables and equipment inside Inner Containment. ,

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4. The cables servin within seven (7) feet g valves IflD2A vertically ofand the IflD37A are routed train B cables serving their al terna te valves, IND10 and 1ND360 respectively, for a distance of thirty-five (35) feet.

Reference Table 1 for associated cables.

5. The Pressurizer llea ter cable routed in the ,innulus doeg .

not present a concern as explained in section V.S.

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6. The separation of the Incore Thermocouples l reference section V.G.) will be implemented.and will comply with Appendix R.

7. The SSF transmitter sensors, along with the normal I operating trans-mitters, for the Steam Generator Level, the Pressurizer Level and the Reactor Coolant System Pressure are located in the Annulus. The separation distances between the SSF transmitter sensors and the normal transmitters are pr.ovided in Table 3.

The equipment Ifsted in section VII.3. and in Table 3 include all of the SSF equipment located in the Annulus. ,

VIII. PROCEDURES (Doghouse) 1.

The SSF related valves and their locations were identified.

2.

It was dete'rmined if an alterna te device! ex:sted that would provide the same function and a) not have cables in the area as the lostulated fire, or

, b) be located outside the Doghouse.

3. When direct alterna tes did not exist, other means of providing the SSF functions.were identified. Reference Section IV.S.

IX. RESULTS (Doghouse) ,

1. The Steam Generator IC Outlet lleader 010wdown Control valve ISM 75A, could spuriously open due to a postulated fire inside the doghouse, however a flow orifice,1SitrE5770, will restrict the amount of flow. This loss would be negligible and would not hinder the capability to achieve and maintain hot stanoby.

2.

The Main Steam Isolation valve ISH3 and the Steam Generator 1C Power Operated Relief valve' 1SV7, are solenoid controlled valves that are de-energized to provide the SSF relat'ed function. This .

de-energization is accomplished in the same manner as described in i section V.2. l t

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I. PROCEDURE

S (Annulus)

The following procedures were used to determine to what extent Appendix R was met inside the Annulus. -

1. The cables associated with the Residual Heat Removal isolation valves and their alternates were identified (reference section V.4. ).

2. Transmitters used for monitoring, during normal operation, that are located inside the annulus, were identified.

3. SSF equipment and cables located inside the annulus were identified, 4 Cable separation distances were determined oy a site evalua-tion and a computer cable routing drawing study.

VII. RESULTS(Annulus)

1. For the functions which have alternates outside inner containment, (reference section V.l .) these alternates are also outside the annulus and therefore do not have any cables routed through the annulus.

2. The functions section V.2.) provided bydisconnect have their the de-energized plugs and solenoids shorting(reference pins located outside the annulus. Thus, the associa ted cables tha t transverse the annulus could not become energized.

3. The following SSF equipment and associated cables (cable # in parenthesis) a '

. located in the annulus and provides means for makeup, a) Standby Makeup Pump (INV758) ,

b) Fuel Transfer Tube Isolation valve INV805A (1*NV742 and 1*NV767) c) Standby Hakeup Pump discharge isolation valve 1NV872A (1*NV743 and 1*NV768).

d) Standby Makeup Pump discharge flow transmitter INVFT6150

, (IllV848).

The devices above are not required to function for a postulated fire in the Annulus due to the availability of the equipment outside.the Reactor Building where a much larger flow is accessible.. -

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3. The Turbine Driven Auxiliary Feedwater Pump / Steam Line isolation valve 1SAS, can be operated via 1SASV0052 which has controls on the SSF Control Board. This valve is also susceptible to spurious opera-tion, however, a postulated fire inside the Doghouse would not affect equipment outside where the normal means of feedwater is available.

X. AUXILIARY BUILDING AND STANDBY SHUTDOWN FACILITY

1. The Residual Heat Removal Islation Valves IND1B and IND37A have an alternate source of power and control from A and B train motor con-trol centers, respectively. These alternate sources will be used only when a fire has disabled the normal power and control cabling.

Open/Close pushbuttons are mounted on the respective motor control center compartments and cabling from these compartments to their respective electrical penetrations will be provided, but will be dis-connected on the penetration end.

2. The remainder of the SSF cables are restricted to the Electrical Penetration Room, the 4KV Essential Switchgear Room, the Auxiliary -

Feedwater Pump Room, Standby Shutdwon Facility, and the ' associated tray and trenches which form the route from the SSF to the Auxiliary Building. Therefore, the equipment and associated cables will not be addressed.

i XI.

SUMMARY

A. Unit 1 The following items comply with Appendix R as stated.

a. Cables 1*ND524, 525, 526, and 595 are protected from 0 to 65" (approximately 65 feet), in the Annulus, with a sprinkler system and fire detection system. This will protect cables for-Valves IND2A and IND37A from the cables associated with their alternates, INDlB and lND368.

b. Cable 1*NC704 is protected with a sprinkler system and fire detection system in the Annulus from 105 to 180 (approximately 75 feet). This will protect the SSF Related NC System Pressure Transmitter Sensor, INCPT5121, and Cable INC810 from transmitter 1NCPT5140.

c. Steam Generator B Level transmitter ICFLT5540 and Cable 1*CF501 in the Annulus are protected with a sprinkler system and a fire detection system. The cable in the Annulus which is approximate-ly six feet in length will be protected from the SSF dedicated

, Transmitter Sensor 1CFLT5622 and Cable ICF675.

d. In Core Thermocouples have been rerouted and separated to meet Regulatory Guide'l.97 and Appendix R. -

B. Unit 2 In the Auxiliary Building, at least one train of equipment required for hnt standby will be protected from redundant trains by three hour rated fire barriers. In the Reactor Building, redundant trains of cable and equipment needed for hot standby will be separated by more than 20 feet.

l TABLE 1:

SSF/ Alternate Function Separation Within Inner Containment 3SF ALTERNATE SEPARATION FUNCTION VALVE VALVE HORZ. VERT.

1N02A INDlB 20 NA ND Isolation /RCS Loop 2 IND37A IND16B 22 NA ND Isolation /RCS Loop 3 Notes:

1. Valve IND37A has cable 1*ND599 routed within six (6) feet vertically of the cables associated with IND36B. Reference Section V.4. for the analysis.

2. Valve INDlB has cables 1*ND503 and 1*ND596 associated with it inside Inner Containment and cables 1*ND524,1*N0525, and 1*ND595 associated with it in the Annulus.

3. Valve IND368 is associated with cable 1*ND518 within Inner Contain-ment and it's respective cable in the Annulus is 1*ND526.

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TABLE 2:

SSF Control Cables / Equipment Within Inner Containment CABLE # CABLE # ALTERNATE WITHIN INNER IN OUTSIDE INNER CONTAINMENT ANNULUS DEVICE SSF FUNCTION ALTERNATE CONTAINMENT ILE607 ILE606 Pressurizer None Hea ter Note l l*NV527 1*NV526 INV89A Normal RCP Seal 1NV91 B Yes 1*NV539 l*NV538 1NV89A Water Return Isol . Viv.

INV760 INV759 INV876 Standby Makeup None INV755 1NV754 1NV876 Pmp Drain Isol. Note 2 Viv.

INV757 INV756 1NV877 Standby None 1 NV761 1NV759 1NV877 Makeup Note 2 Pmp/RCP Seal Water Isol. Viv.

1*ND504 1*ND527 1ND2A ND/RCS Train A 1NDlB No Isol. Viv.

1 *ND511 1*ND523 1ND37A ND/RCS Train B IND36B No 1*ND599 1*ND528 1ND37A Isol. Viv.

1*BB545 1*BB571 1BB60A S.G. Secondary 1BB61B Yes 1 *B8518 1 *BB 570 1BB60A Side Isol. 1BB149B Yes 1*BB508 1*BB507 1BB60A

, 1 *BB510 1*BB509 1BB8A 18B147B Yes 1*BB523 1*BB570 1BB8A 18B10B Yes 1*BB542 1*BB571 1BB8A

, 1*BB543 1*BB571 1BB19A 18B218 Yes 1 *BB519 1*BB570 IBB19A 1881508 Yes 1*BB506 1*BB505 1BB19A 1*BB544 1 *BB 571 1BB56A 18B57B Yes ,

1*BB524 1*BB570 1BB56A 1881488 Yes  !

1 *BB512 l*BB511 1BB56A, l

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l CABLE ! CABLE # ALTERNATE WITHIN INNER IN OUTSIDE INNER CONTAINMENT ANNULUS DEVICE SSF FUNCTION ALTERNATE CONTAINMENT L*NM578 1*NM611 1NM3A Nuclear Sampling INM7B Yes 1*NM540 1 *NM610 1NM3A System Isol.

1 *NM515 1"NM514 1NM3A Vlvs.

1*NM579 l*NM611 1NM6A INM7B Yes 1*NM541' l *NM610 INM6A 1 *NM517 1 *NM516 INM6A 1*NM580 1 *NM61-1 1NM22A INM26B Yes 1*NM542 1 *NM610 1NM22A 1*NM511 1 *NM510 INM22A 1*NM581 1*NM611 1NM25A INM268 Yes 1*NM543 1 *NM610 1NM25A o 1*NM509 1*NM508 1NM25A lENA524 lENA533 Incore Temp. Hot & Cold No lENA525 lENA534 T/C Monitoring Leg RTDs lENA526 lENA535 (Note 3) 1ENA527 l ENA536,1 NC809 l ENA712 l ENA713 Reference RTO 1*NC838 1*NC837 1NC250A RCS Isolation None 1 *NC861 1*NC860 1NC250A (Head Vent) Note 4 1*NC840 1*NC839 lNC253A None 1*NC863 1*NC862 INC253A Note 4 1*NC596 1*NC830 INC32B PORV 1NC31B No 1*NC823 1*NC830 (Isolation) Note 5 1*NC599 1*NC828 1NC34A INC33A No l*NC825 1*NC824 Note 5 1*NC596 1*NC830 1NC36B INC358 No 1*NC823 1*NC830 INC36B Note 5 1*NV547 1*NV835 1NV1A RCS/CVCS INV2A No Isol. Viv. Note 5 l*NV581 1*NV836 1NV1228 RCS/CVCS 1NV123 or No Isol. Viv. 1NV124B Note 5 D

TABLE 2 NOTES SSF CABLES WITHIN INNER CONTAINMENT

1. It has been determined that the Pressurizer Heater is not required to perform the necessary SSF functions.

2. These cables are associated with valves, used in the alignment of the Standby Makeup Pump, which are not required to operate due to a postulated fire inside containment,and would not affect the normal means of charging which is located cutside the Reactor Building.

3. An alternate ' for the Incore Thermocouples is a pair of Wide Range RTDs located in the hot and cold legs of one loop. However, the RTD cables may be routed with the Incore Thermocouple cables, making them unrel ia bl e.

Due to Licensing commitments to meet Reg. Guide 1.97, the Incore Thermocouples will be separated and at that time, Appendix R will be taken into account and satisfied.

4. These SSF Isolation functions are initiated because of the low flow capability of the Standby Makeup Pump. However, the reasoning of Note 2 above applies here as well.

5. These cables are de-energized by disengaging connectors and installing shorting pins. Therefore the solenoid operated valves,which they control, fail to their respective SSF position and are not susceptible to spurious operation.

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TABLE 3:

SSF/ Normal Function Transmitter Separation SSF DEDICATED TRANSMITTER NORMAL PLANT SENSOR TRANSMITTER SEPARATION (FT)

(NOTE 1) CABLE # (NOTE 1) CABLE # (NOTE 2)

DEVICE # (NOTE 3) ' DEVICE # (NOTE 3) CHNL. HORZ. VERT. FUNCTION I NCLT5151 INC811 1NCLT5160 1*NC608 1 NA 5 Pr.essurizer Level

- INCLT5150 1 *NC615 2 19 NA 1 NCLT5170 1*NC622 3 64 NA INCPT5121 INC810 INCPT5120 1*NC703 Train 10 15 NC System A Pressure I NCPT5140 1*NC704 Train 2 NA B

I CFLT5612 1CF674 1CFLT5501 1*CF663 1 NA 1 Steam Generator 1 CFLT5510 1*CF505 2 1 NA A Level I CFLT5500 1*CF509 3 7 NA 1CFLT5490 1 *CF513 4 NA 20

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1CFLT5622 1CF675 1CFLT5540 1 *CF501 1 11 17 Steam Generator ICFLT5521 1*CF665 2 1 NA B Level 1CFLT5530 1 *CF510 3 NA 1 1CFLT5520 1 *CF514 4 NA 5 1CFLT5632 1CF676 1CFLT5570 1*CF503 1 13 12 Steam Generator 1CFLT5551 1*CF666 2 3 3 C Level 1CFLT5560 1*CF511 3 NA 1 1CFLT5550 1 *CF515 4 24 NA

'lCFLT5642 ICF677 1CFLT5591 1*CF664 1 NA 5 Steam Generator 1CFLT5600 1*CF506 -2 20 53 D Level 1CFLT5590 1 *CF512 3 8 NA 1CFLT5580 1*CF539 4 5 5 TABLE 3 NOTES

1. The SSF related transmitter sensors and the normal operating transmitters are located is the Annulus except for the normal operating pressurizer level transmitter, which is located within Inner Containment. The SSF related transmitter amplifiers are located in the Auxiliary Building col . AA-47, elev. 580 ft.

2. This is the minimum distance of separation.

3.. Cables that are located in the Annulus. -

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FIGURE 1 STEAM GENERATOR 1 A SECONDARY SIDE FLOW PATH SG 1 A C 3 C 3

\ / E l l E YD S AM J

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--e,K-K l RB l l N

V g m . GENERATOR BLOWDOWN 1BB56A I I 1BB57B -

l l TANK CVlRB lDH DH l YD -l TB C 3

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IBB148B 2 e

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ATTACHfiENT 2 The safe shutdown capability outside the Reactor Building is assured by the separation of the shutdown related cables / equipment from alternate cables /

equipment by three hour fire barriers. Associated circuits, if present, which may be associated with the redundant shutdown cables / equipment, do not have the same three hour fire barrier requirements.

Associated cables can be divided into two categories as follows:

1) The cables considered associated by being electrically connected to a shut-down power distribution system.

2) The cables considered associated by proximity, by sharing raceway, etc.

The first category does not exist at Catawba due to the use of optical isola-tors which isolate the Non QA Condition cables from the QA Condition' power sources. The second category does not exist at Catawba either, due to design requirement for cable separation which is as follows:

Neither redundant Class IE circuits nor a combination of Class IE and Non Class IE circuits may be routed through the same raceway.

Therefore, Catawba meets Appendix R in regard to associated cables, since none '

of the cables at Catcwba fall into the category of associated cables.

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1-DUKE P0WER COMPANI

. CATAWBA NUCLEAR STATION I

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INFORMATION IN SUPPORT OF STANDBY SHUTDOWN FACILITY t

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TABLE OF CONTENTS Page

1.0 INTRODUCTION

1 2.0 STRUCTURE 1

2.1 FACILITY DESCRIPTION 1 2.2 DESIGN BASES 1 3.0 STANDBY SHUTDOWN SYSTEM 2 3.1 SYSTEM PURPOSE 2 3.2 DESIGN BASIS 2 3.2.2 CRITERIA FOR FIRE PROTECTION 2 3.3 DESIGN DESCRIPTION P 2 3.3.1 SYSTEM DESCRIPTION 2 3.3.1.1 Gcneral Description 3 3.3.1.2 Primary Side Volume Control 3 3.3.1.3 Secondary Side Volume Control 3 3.3.1.4 Primary Side Natural Circulation 4 3.3.1.5 Main Steam Safety Valves 4 3.3.1.6 Instrumentation and Controls 4 3.3.l'.7 Supporting Services 4 3.3.1.8 Electric Power Supply 4 3.

3.2 DESCRIPTION

OF INDIVIDUAL COMPONENTS 4 3.3.2.1 Standby Makeup Pump 4 3.3.2.3 Turbine Driven Auxiliary Feedwater Pump 5 3.3.2.4 Pressurizer Heaters 5 -

3.3.3 INSTRUMENTATION AND CONTROL (Per Unit) 5 3.3.3.1 Tempera ture 5 3.3.3.1.1 Reactor Coolant System Temperature 5 3.3,3.2 Pressure 5 3.3.3.2.1 Reactor Coolant System Pressure 5 3.3.3.2.2 Standby Makeup Filter Differentia.1 Pressure 5

3.3.3.2.3 Turbine Driven Auxiliary Feedwater Pump Suction Pressure 5 i

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Page 3.3.3.3- Level 5 3.3.3.3.1 Pressurizer Level 5 3.3.3.3.2 Steam Generator Level 6 3.3.3.4 Flow 6 3.3.3.4.1 Standby Makeup Pump Discharge Flow 6 3.3.5 PERIODIC TESTING 6 4.0 ELECTRICAL POWER SYSTEMS 6 4.1 DESIGN BAS _ES 6 4.2 DESIGN DESCRIPTION 6 4.2.1 AC POWER SYSTEM 7

4. 2.1.1 600/208/120 VA SSF Power System 7 4.2.2 DC POWER SYSTEM 8 4.2.2.1 250/125 VDC SSF Power System 8 4.2.3 SSF DIESEL GENERATDR AND AUXILIARIES 8 4.2.3.1 Starting Circuit 8 4.2.3.2- Starting System 8 4.2.3.3 Intake and Exhaust 9 ,

4.2.3.4 Diesel Generator Protection 9 4.2.3.5 Fuel Oil 9 4.2.3.6 Lube Oil 10 4.2.3.7 Jacket Cooling '

10 5.0 SSF SUPPORT SYSTEMS 10 5.1 DESIGN BASES 10 5.2 DESIGN DESCRIPTION 10 5.2.1 SSF LIGHTING SYSTEMS 10 5.2.1.1 Normal Lighting System 10 5.2.1.2 Emergency DC Lighting System 10 5.2.2 FIRE PROTECTION AND DETECTION 10 5.2.2.1 Protection 10 5.2.2.1.1 Sprinkler System 11

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5.2.2.1.2 Hose Racks .

11 l 5.2.2.2.2 Detection 11 t

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Page 5.2.3 HVAC 11 5.2.3.1 Ventilation System 11 5.2.3.2 Air Conditioning System . 12

.5.2.4 SSF SUMP SYSTEM 12 4

9 6.0 DESIGN EVALUATION 12 .

6.1 , DESIGN BASES 12 6.2 EVALUATION OF FIRE PROTECTION RELATED FEATURES 13 O

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1.0 INTRODUCTION

In a May 1,1978 submittal, Duke Power Company provided a conceptual descrip-tion of the Standby Shutdown Facility (SSF) for McGuire Nuclear Station. This concept was reviewed and approval provided by the NRC staff in March,1979.

A similar facility, with individual power supply, instrumentation and controls to bring the units to Hot Standby Condition, is provided at Catawba. This facility fulfills requirements of BTP CMEB 9.5-1 Item C.S.C, and Appendix R,Section III G.2 as described herein. This submittal includes mechanical, elec-3 trical, structural, and support system descriptions.

The Standby Shutdown System (SSS) is designed to mitigate the consequences of postulated fire incidents to one or both units at Catawba. The SSF contains independent sources of AC and DC electrical power and associated electrical distribution systems and support systems. The SSS supplements the current shutdown capability described in the Catawba FSAR. It would be operated only in the event installed normal and emergency systems are inoperable. Manual operator action is required to actuate the system.

2.0 STRUCTURAL 2.1 Facility Description The Standby Shutdown Facility is a steel frame, masonry, structure consisting of a diesel generator room, electrical equipment room, battery room, control room and on the second elevation a shared equipment room. The diesel generator room occupies the north side of the structure. This room is the equivalent of two stories in height although there is no intermediate floor level. The remainder of the rooms occupy the east side and south end of the structure.

The control room, battery room, and shared equipment rooms make up the two levels south of the diesel generator room. A single level electrical equipment room occupies the east end of the structure. The diesel generator floor is six inches above grade. The shared equipment room is one level above the battery and control rooms. Access is provided by one equipment door and one personnel door at grade level . These are three hour fire rated door units. Openings for HVAC air intake and discharge are provided. The intake is a protected opening flush with the second level of the north end of the diesel generator room. The discharge, a walled labyrinth area, is at the north end of the diesel generator room. The genecal arrangement of major equipment and structures is in Figure 2.1-1.

2.2 Design Bases The Standby Shutdown Facility is not designed to withstand design basis seismic loadings nor is it nuclear safety related. The facility is designed in accord-ance with requirements for Category III structures as defined in the Catawba FSAR Table 3.2.1-1.

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w 3.0 STANDBY SHUTDOWN SYSTEM 3.1 SYSTEM PURPOSE The Standby Shutdown System provides an alternate and independent means to achieve and main'.ain a hot standby condition for one or both units. This sys-tem supplements the current shutdown capability described in the Catawba FSAR.

The system has the capability to maintain hot standby in both units for 3-1/2

• days (12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> more than the Appendix R requirement) without credit for use of equipment made available through damage control measures.

Since the Standby Shutdown System is provided as an alternate means to achieve and maintain a hot standby condition following postulated fire events, the sys-tem (except where it interfaces with existing safety related systems) is designed in accordance with accepted fire protection requirements and thus is neither designed to withstand design basis seismic loadings nor is it nuclear safety related.

3.2 DESIGN BASIS 3.2.1 CRITERIA FOR FIRE PROTECTION The SSF design far fire protection concerns is based on the following criteria:

A) A fire is not postulated concurrent with non-fire-related failures in safety systems, other plant accidents, or the most severe natural phenomena.

B) Destruction of all equipment and cabling within a single fire zone shall not preclude the capability to achieve and maintain hot standby. No credit for use of equipment made available through damage control measures is allowed for a period of 3-1/2 days.

C) No credit is allowed for fire protection, devices.

The design basis is to maintain hot standby conditions for 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> (without offsite power) while necessary damage control measures are taken. After 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />, it is assumed offsite power is restored and the plant is taken to cold shutdown conditions. The method of achieving cold shutdown will be determined based on what equipment is available which in turns depends on the location and extent of damage caused by the fire and any damage control measures taken to restore operability.

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l The Catawba SSS has been designed to meet the intent of Appendix R by providing separation in order to maintain hot standby conditions. Once damage control measures have been taken, cold shutdown is achieved through use of the same equipment normally used to establish this condition.

1 3.3 DESIGN DESCRIPTION l 3.3.1 SYSTEM DESCRIPTION 2

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3.3.1.1 General Description 1 -

The Standby Shutdown System consists mainly of one diesel generator set and

, supporting equipment, one standby makeup pump per unit with filter, valves and associated piping, and one turbine driven auxiliary feedwater pump per unit

', with supporting equipment. Utilizing this equipment, hot standby capability is achieved as follows.

3.3.1.2 Primary Side Volume Control A standby makeup pump is located in the annulus of each unit to supply makeup .

to the Reactor Coolant System'should the normal system be unavailable. The 4

pump provides makeup to the Reactor Coolant System to recover normal system leakage and reactor coolant pump seel leakage. The pump draws borated water l 3

from the spent fuel pool through a three inch pipe connected to the fuel trans-i fer tube in the annulus. This line contains one normally closed electric motor -

c operated valve which is controlled from the SSF control room. This single, normally closed valve, is adequate isolation between the Class B fuel transfer i- tube and the Class E pump suction piping. There is sufficient borated water available from the spent fuel pool to allow 3-1/2 days of standby makeup pump operation without adverse effect on the spent fuel pool (assuming the spent

fuel pool cooling system is not available and maximum spend fuel heat load).

A filter in the pump discharge piping removes debris which might be harmful to i the reactor coolant pump seals. This portion of the Standby Shutdown System is shown in FSAR Figures 9.3.4-6 and 9.3.4-9 (Duke Flow Diagrams CN-1554-1.5 and

CN-1554-1.8).

l The standby makeup pump is a rositive displacement design and therefore adds a constant quantity of borated water to the Reactor Coolant System. If it becomes necessary to remove some water to maintain acceptable pressurizer -

j liquid level, electric motor operated valves, powered by the standby shutdown i diesel, can be opened to letdown RCS water to the pressurizer relief tank.

j These valye,s are operated from the SSF control room. Refer to FSAR Figures l 5.1-1 and 5.1-2 or Duke Flow Diagrams CH-1553-1.0 and CN-1553-1.1.

3.3.1.3 Secondary Side Volume Control l

The existing turbine driven auxiliary feedwater pump is utilized to maintain

adequate secondary side volume. The water in the embedded condenser circulat-l ing water pipe will be utilized to maintain hot standby for at least 3-1/2 days.

I The Nuclear Service Water. System (FSAR Figures 9.2.1-6 and 9.2.1-10 or CN-1574-2.1 and CN-1574-2.5) provides the flow path from embedded pipe to the l Auxiliary Feedwater System. Two direct current (DC) power operated valves are

required to provide an assured source of water to the turbine driven auxiliary ,

feedwater pump (Refer to FSAR Figure 10.4.9-1 or Duke Flow Diagram CN-1592-1.0).

These valves will open automatically on low pump suction pressure. Steam-operator low level logic has been added to insure the automatic start of the turbine driven' auxiliary feedwater pump. The pump discharge valves are normal-

. ly open, this injection to the steam generators is assured (Refer to FSAR Figure 10.4.9-2 or Duke Flow Diagram CN-1592-1.1).

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3.3.1.4 Primary Side Natural Circulation Decay heat is removed from the core by utilizing primary side natural circula-

. tion. With the Auxiliary Feedwater System operating, the Reactor Coolant Sys-tem is capable of providing adeq'uate natural circulation flow for core heat removal in the event of a loss of normal station power.

3.3.5 Main Steam Safety Valves The main steam safety valves lift and dump steam to the atmosphere. These valves maintain a constant pressure in the secondary side which in turn main-tains the Reactor Coolant System at the correct-temperature and pressure to

! maintain hot standby.

i 3.3.1.6 Instrumentation and Controls 4

Sufficient instrumentation and controls.are provided to allow operator initia-tion and control _ of the orderly progression of each unit to hot standby condi-tions. These' instruments and controls are located in the Standhy Shutdown Facility.

3.'3.1.7 Supporting Services -

t j The Standhy Shutdown Facility (SSF) is provided to house some of the equipment i described herein. This equipment includes the diesel generator, battery, power i _ distribution equipment, HVAC for the structure, shutdown panels and miscellane-ous support equipment.

3.3.1.8 Electric Power Supply An _ independent power system is supplied to support the above equipment and instrumentation. See Section 4.0 for further information.

3.3 DESCRIPTION

OF INDIVIDUAL COMPONENTS 3.3.2.1 Standby Makeup Pump

, The standby makeup pump delivers water from the spent fuel pool to the Reactor Coolant System at the rate of 26 GPM. Approximately 18 GPM is required for seal leakage and 8 GPM for Reactor Coolant System makeup and boration. Makeup is through the reactor coolant pump seals. The standby makeup pump is a posi-tive displacement pump driven by an induction motor, powered hy the star.dby shutdown power supply. .The pump is located sufficiently below the fuel pool to -

assure that adequate net positive suction head is available.

3.3.~2.2 Standby Makeup Filter ,

The standby makeup filter removes particulate matter larger than five microns which could be harmful . to the seal faces. The filter is sized to accept three times the flow output of the standby makeup pump with a negligible pressure l drop. Fouling of this filter is not considered to be a problem since the fuel pool .is normally filtered to three microns and since this filter has been con-  :

servatively sized. ,

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3.3.2.3 Turbine Driven Auxiliary Feedwater Pump Refer to the A'uxiliary Feedwater System description in the Catawba FSAR Section 10.4.9.1 for the sizing criteria for this pump.

3.3.2.4 Pressurizer Heaters One subbank of pressurizer heaters (approximately 70 KW) are powered from the standby shutdown diesel. These heaters may be necessary within approximately 15 hours1.736111e-4 days <br />0.00417 hours <br />2.480159e-5 weeks <br />5.7075e-6 months <br /> following the initiating event to insure that the steam bubble remains in the pressurizer.

3.3.3 INSTRUMENTATION AND CONTROL (Per Unit) ,,

'3.3.3.1 Temperature

,3.3.3.1.1 Reactor Coolant System Temperature This instrument displays the Reactor Coolant System temperature in the SSF using existing incore instrument thermocouples. Manual means are provided in the SSF of switching the power supply and output signal from the normal path to the Standby Shutdown Facility.

3.3.3.2 Pressure

3. 3. 3. 2.1 Reactor Coolant System Pressure This instrument displays the Reactor Coolant System pressure in the SSF. The transmitter is separate from the normal Reactor Coolant System pressure trans-mitters and the receiver gauge is located on the SSF control panel.

3.3.3.2.2 Standby Makeup Filter Differential Pressure A local pressure gauge in the annulus indicates the differential pressure across the Standby Makeup Filter.

3.3.3.2.3 Turbine Driven Auxiliary Feedwater Pump Suction Pressure Pressure switches are located at the suction of the Turbine Driven Auxiliary Feedwater Pump and powered from the SSF. These switches automatically align -

the pump suction to the embedded condenser circulating water pipe on low pres-sure. This assures a source of water for the Auxiliary Feedwater' Pump.

3.3.3.3 Level 3.3.3.3.l Pressurizer Level This instrumentation displays the pressurizer liquid level on the SSF control panel. The operator utilizes this readout to control letdown. The transmitter is powered from the SSF power supply..

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3.3.3.3.2 Steam Generator Level Separate and dedicated steam generator level transmitters are supplied to indi-cate the liquid level in each Steam Generator on the SSF control panel. The transmitters are powered by the SSF power supply and the receiver gauges are located on the SSF control panel. An electrical logic scheme is pro'vided such that a two out of four low level signal will automatically open the steam supply which starts the Turbine Driven Auxiliary Feedwater Pump.

3.3.3.4 Flow 3.3.3.4.1 Standby Makeup Pump Discharge Flow

, This instrumentation indicates the Standby Makeup Pump discharge flow rate at the SSF control panel. This instrument is mainly utilized for periodic testing of the Standby Makeup Pump.

3.3.5 PERIODIC TESTING A complete inplace periodic test of the Standby Shutdown System cannot be done without upsetting the water chemistry in both the primary and secondary side

• systems. However, periodic testing is performed for individual system compon-nents. ,

4.0 ELECTRICAL POWER SYSTEMS 4.1 DESIGN BASES -

The Standby Shutdown Facility (SSF) Power System is designed to provide a reli-able source of AC and DC power to those loads required to achieve and maintain hot standby conditions in either or both of the two Catawba units for the fol-lowing events:

1. Lose of all non-SSF onsite (safety and non-safety) and offsite po.ter.

2. Loss of control capability for the normal shutdown systems.

The SSF Power System is designed to function independent of all other onsite and offsite power systems. For achieving and maintaining hot standby condi-tions, this system serves as a backup to existing redundant plant power sys-tems. The SSF Power System design is such that any one failure in the system will not prevent the existing plant power systems from performing ~ their intend-ed function. ConvEcsely, any one failure in the existing plant power systems will not prevent the SSF Power System from performing its intended function.

The SSF Power System is not desinged to withstand design basis seismic loadings, nor is its nuclear safety related, except for interfaces to existing safety

• related systems.

4.2 DESIGN DESCRIPTION The SSF Power System includes onsite 600 VAC, 208 VAC,120 VAC, .250 VbC, and 125 VDC power. The'SSF Power System including.its associated loads is shown on Figures 4.2-1, 4.2-2, 4.2-3, 4.2-4, and Tables 4.2-1, 4.2-2, and 4.2-3.

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4.2.1 AC POWER SYSTEt1 4.2.1.1 600/208/120 VAC SSF Power System

'The 600/208/120 VAC SSF Power System consists of one 600 VAC shared load center, one 600 VAC non-safety shared motor control center, two 600 VAC safety related motor control

• centers, two inverter supplied 120 VAC systems, and a 208/120 VAC power panelboard. ,

600 V Load Center ISLXG is loc'ated in ,the SSF and is shared by the two Catawba un i ts . This load center is normally energized from the Unit 16900 V Power System and is available to power the SSF 125 VDC battery chargers, and 600 V Motor dontrol Center SMXG. Standby power is also available to the 600 VAC SSF Power System by means of the SSF diesel generator. The SSF standby power source is described in Section 4.2.3.

In the event that the normal power source to the 600 VAC SSF load center is lost, the incoming feeder breaker is manually tripped a separate it from the normal source, and the SSF diesel generator is manually started and connected to the load center. The 600 VAC SSF loads are manually sequenced as necessary to achieve and maintain hot standby.

600 VAC shared Motor Control Center StiXG, located in the SSF, is tne zlternate power supply to two 600 VAC safety-related motor control

• centers (IEMXS and 2El1XS), and is the normal power supply to non-safety loads required for hot standby of either or both units from the SSF.

• Motor Control Center SMXG also supplies those loads directly associated with the SSF (e.g., diesel generator auxiliaries, SSF sump pumps and SSF lighting

. system)..

The two 600 VAC safety-related motor control centers located in the station are normally energized from their associated Class lE auxliary power systems. Upon loss of the Class lE auxiliary power system, the motor control centers will be manually transferred to 600 VAC SSF Motor Control Center StiXG where they can be powered from the SSF diesel generator. A kirk key interl'ock scheme is provided between the normal and alternate motor control center feeder breakers to pre-vent par,alleling of the SSF Power System and the Class lE~ auxiliary power system.

The 600 VAC SSF Power System is shown on Figure 4.2-1 and Tables 4.2-1, 4.2-2, and 4.2-3. .

The 208/120 VAC portion of the 600/208/120 VAC Power System distributes power to all SSF 208 VAC and interruptible 120 VAC 16 ads (such as fans and space heating equipment). The 600 VAC motor control center supplies power to 208 VAC Power Panelboard SKPG via a 600/208 VAC transformer. This portion of the power system is shown on Figure 4.2-3.

The uninterruptible 120 VAC portion of the 600/208/120 VAC SSF Power System normally receives its power from the 250/125 VDC SSF Power System via Static Inverter 2KSI. Inverter 2 KSI has two outputs with one output supplying power to the security system and one output supplying the SSF instrumentation and controls (Panelboard SKXP). This inverter system has an alternate source of power from 600 VAC Motor Control Center 2MXX via a 600/120 VAC transformer.

120 VAC Panelboard SKXP is shown on Figure 4.2 4.

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• Upon loss of a static inverter (s) or the 125 VDC SSF Power System, the inverter system (s) is automatically transferred to its alternate source. .

4.2.2 DC POWER SYSTEM 4.2.2.1 250/125 VDC SSF Power System The 250/125 VDC SSF Power System consists of three 125 VDC batteries and asso-cia,ted chargers, one DC distribution center, and two power panelboards.

This system is designed'to provide an uninterruptible source of power for the Catawba security system and to supply the SSF equipment controls and instrumen-tation.

Normally, two 125 VDC batteriesP and associated chargers are connected to the 250/125 VDC distribution center to supply the 250 VDC and 125 VDC SSF loads.

In this alignment, each battery is floated on the distribution center and is available to assume load without interruption upon loss of its associated bat-tery charger or the charger's AC power source. The other 125 VDC battery and associated charger is in a' standby mode and can be manually connected to the 250/125 VDC distribution center to replace one of the normal 125 VDC batteries and/or the normal charger.

All of the battery chargers are fed from the shared 600 VAC load center and are designed .to prevent their associated battery from discharging back into any internal charger circuits in the event of an AC power failure or a charger malfunction.

Any two of the three 125 VDC batteries connected in a 250/125 VDC combination are sized to supply the required SSF and security loads for a minimum of one hour without its associated charger and without decreasing the battery voltage

.below an acceptable level.

The 250/125 VDC SSF Power System is shown on Figures 4.2-2 and 4.2-4. e 4.2.3 SSF DIESEL GENERATOR AND AUXILIARIES -

The SSF Power System is provided with standby power from a dedicated diesel ,

generator. This.SSF diesel generator is rated for continuous operation at 700 KW, 0.8 pf, and 600 VAC. The SSF design load does not exceed the continuous rating of the diesel generator. The auxiliaries required to assure proper operation of the SSF diesel generator are supplied entirely from the SSF Power System. -

4.2.3.1 Starting Circuit s

The SSF diesel generator starting system must be manually initiated from the SSF.

4.2'.3.2 Starting System -

L The diesel engine has dual 24 VDC positive engagement starting motors. A 24 VDC battery and charger combination supplies power to the starting motors. -

This starting. system is capable of providing ten successive starts.

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4.2.3.3 Intake and Exhaust The combustion air for the diesel is taken from the diesel room area and passes through a replaceable filter. The diesel exhaust travels through silencers and

- then is discharged outside the building via an outlet plenum.

• 4.2.3.4 Diesel- Generator Protection The diesel generator protection system initiates automatic and immediate pro-tective action to prevent or limit damage to the SSF diesel generator. The following protective trips are provided to protect the diesel generator at all times and are not bypassed when the dies.el generator is in the emergency mode:

1. Engine Overspeed

2. Generator Differential Protection Overspeed protection is provided by a centrifugal overspeeg trip device, the setpoint of which is above the engine speed of a full-load rejection. Genera-tor differential protection is provided through relaying in the 600 volt load cqnter. -

The following additional trips and associated alarms are provided to protect the diesel generator during test periods:

, 1. Low Pressure Lube Oil - .

2. High Temperature Jacket Water *

3. Generator Overcurrent Protection ,

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GeneratorReversePowerPro(ection 5.* Generator Ground Protection These electrical trips are bypassed when the diesel generator is in the emer-gency mode. However, the associated alarms remain functional to alert the operator to any abnormal conditions.

4.2.3.5 Fuel Oil The fuel oil storage and supply ;ystem fo'r the standby diesel is entirely sepa-rate from those which supply the

h emergency diesels. The system consists of an underground fuel oil storage tank, a recirculation loop containing a pump and a filter to maintain the fuel oil in the storage tank within acceptable limits, a fuel oil day tank and pump to maintain day tank level, and the duplex filter unit and fuel oil pump which are a part of the shutdown diesel package.

The underground storage tank contains sufficient fuel to' supply the shutdown diesel for over 3-1/2 days of continuous operation. The day tank contains suf-l ficent fuel to start the engine and permit orderly shutdown of the diesel on loss of fuel from the storage tank. The equipment and piping associated with the recirculation loop and day tank which is located inside the SSF building l are located within a retaining wall which would control spreading of fuel oil i due to spills or leaks.

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4.2.3.6 Lube Oil The lube oil system is an entirely.self-contained part of the diesel engine skid. Draining the lube oil sys' tem completely, refilling, or adding lube oil <

when necessary is a manual operation.

4 4.2.3.7 Jacket Cooling The engine cooling water system is supplied as a portion of the diesel package.

It is a closed loop which rejects heat through a radiator to air which is sub-sequently discharged from the building.

5.0 SSF SUPPORT SYSTEMS 5.1 DESIGN BASES -

Thg SSF support systems are designed to provide lighting, fire protection, fire detection, service water, HVAC. sump drainage, and potable water for the Stand-by Shutdown Facility. The lighting, the fire protection system, the fire detection system, the HVAC system, the sump drain, age system, and the potable water system are not seismically designed or safety related. The fire protec- #

tion systems and the fire detection system are designed and constructed to meet National Fire Codes as appropriate. Fire protection and detection equipment is Underwriter's Laboratories listed or Factory Mutual approved.

5.2 DESIGN DESCRIPTION .

5.2.1 SSF LIGHTING SYSTEMS '

5.2.1.1 Normal Lighting System Normal lighting for the SSF is provided by fluorescent and high pressure sodium lighting units. These lighting units are located to provide adequate levels of light with good distribution throughout the structure.

The normal lighting system is powered from the 600 VAC SSF Motor Control Center SMXG via a 600/208/120 VAC dry-type transformer. In the event that the normal source of power to MCC SMXG is lost and the SSF is being powered by the diesel generator, the normal lighting system will be reconnected via MCC SMXG.

5.2.1.2 Emergency DC Lighting System Emergency DC lighting for the SSF is provided by self-contained 12 VDC battery pack lighting units. These units are located to provide adequate levels of lighting for control panel operation and for entering and leaving the structure.

These battery pack lights are energized automatically upon a loss of voltage in the normal lighting system power supply.

L 5.2.2 FIRE PROTECTION AND DETECTION 5.2.2.1 Protection The Catawba Fire Protection System suppljps the following primary and secondary protection systems for the Standby Shutdown . Facility. '

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. a e-Area Primary Protection Secondary Prptection Diesel Engine Room Automatic Sprinkler 11ose Racks

, System .

Battery Room Hose Racks C02 Portable Extinguishers Control Room Hose Racks C02 Portable Extinguishers Electrical Equipment' Area H'ose Racks C02 Portable Extinguishers, o

HVAC Equipment Area Hose Racks C02 Portable Extinguishers 5.2.2.1.1 SprinklerSystIm The SSF diesel generator and diesel generator room are protected by a closed head sprinkler system. Each sprinkler head fuses and discharges water when it is heated to its rated temperature. An alarm check valve is installed in the sprinkler header which alarms to the Unit 1 and 2 control room when activated.

5.2.2.1.2 Hose Racks Hose racks are installed throughout the SSF. From these locations, the hose lengths are such that the entire SSF can be served.

5.2.2.2.2 Detection Detection devices are located throughout the Standby Shutdown Facility. These devices alarm locally and annuciate in the Unit I and 2 control room in the event of a fire. ,,

5.2.3 HVAC The purpose of this system is to satisfy the. heating, ventilating and air con-ditioning requirements of the Standby Shutdown Facility. The system consists

, of an air conditioning subsystem for the battery and control rooms, and a ven-tilating subsystem for the remaining areas of the SSF. Components necessary for SSF operation are powered from the SSF diesel generator. All HVAC compo-nents are controlled from a central panel in the HVAC equipment room.

5.2.3.1 Ventilation System The electrichl equipment room and HVAC equipmemt room are each provided with a wall mounted supply fan, intake and relief dampers, and electric room thermo-stat for fan control. Fan capacities are selected to maintain maximum area temperatures below 105 F. Electric unit heaters are provided to maintain mini-mum area temperatures of 60 F during periods of insufficient heat load.

The diesel generator room is provided with a wall mounted supply fan, intake and relief dampers, and room thermostat for far. control. Fan capacity is selected to maintain maximum area temperature below 105 F during periods when the diesel generator is not operating. Electric unit heaters are provided to

. maintain a minimum area temperature 'of 60 F during periods when the diesel generator is not operating. Room ventilation during diesel generator operation s

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is provided by the engine mounted radiator cooling fan, and room conditions will vary according to outdoor air temperature. Sidewall intake and relief dampers provide a flow path for engine radiator cooling air.

5.2.3.2 Air Conditioning System The battery and control rooms are served by a packaged, air-cooled air condi-

'tioning unit located in the HVAC equipment room. Duct mounted electric heating coils and electric room thermostats are provided to maintain desired conditions in each room. Equipment capacities are selected to maintain the battery room at 771PF and the control room at 7515 F. A centrifugal roof exhauster serves the battery room to limit hydrogen gas accumulation.

5.2.4 SSF SUMP SYSTEM The SSF sump system provides a collection and discharge function for normal equipment drainage within the Standbh Shutdown Facility. The main components of the system are the sump and a sump pump which handles the flow routed to the sump via the floor drain system located throughout the SSF. The pump receives power from the SSF Power System.

6.0 DESIGN EVALUATION -

6.1 DESIGN BASES The Standby Shutdown Facility (SSF) is designed as a standby system for use under extreme emergency conditions. The system provides additional " defense-in-depth" protection for the health and safety of the public by serving as a

• backup to existing safety systems. The SSF is provided as an alternate means to achieve and maintain hot standby conditions following postulated fire or sabotage events, and is designed in accordance with criteria associated with these events. Loss of all other station power is assumed for each event. In that the SSF is a backup to existing safety systems, the single failure crite-rion is not required. However, failures in the SSF systems will not cause failures or inadvertent operations in existing plant systems.

The SSF requires manual activation and would only be activated under adverse fire conditions when existing redundant emergency systems are not available. t The SSF utilizqs equipment in vital areas (e.g., containment, SSF) to achieve and maintain hot standby conditions.

l The SSF has been designed to:

1. Maintain a minimum water level above the reactor core.

2. Achieve and maintain cold shutdown reactivity conditions.

3. Maintain the primary coolant system filled to a sufficient level in the pressurizer to assure natural circulation and core cooling and maintain sufficient secondary side cooling water.

4. Transfer decay heat from the fuel to an ultimate heat sink.

5. Provide direct readings of the process variables necessary to perform and control .the above functions.

6. Provide process cooling, lubrication, etc., for equipment required for safe shutdown.

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3.2 EVALUATION OF FIRE PROTECTION RELATED FEATURES In some locations (such as the cable spreading room), it is not feasible to protect redundant safe shutdown systems against adverse effects of fire or fire suppression activities. Only through the use of fire protection features can these safe shutdown systems be protected. Because for given fire areas, the redundant safe shutdown systems are*too close to each other. Therefore, an alternative shutdown capability has been provided from the SSF which is indepen-dent from the areas mentioned above. .

This dedicated safe shutdown cap' ability assures that fire protection features are provided for structures, systems, and components important to safe shut-down, which will be capable of limiting fire damage so that:

A. One train of systems necessary to achieve and maintain hot shutdown condi-tions from either the control room or emergency control station (s) is free of fire damage; and B. Systems necessary to achieve and maintain cold shutdown from either the control room or emergency contrdi station (s) can be repaired within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />. ,

In the Auxiliary Building, at least one train of equipment needed for hot shut-down is separated from other. trains by three hour rated barriers. In Unit 1 Feactor Building, automatic sprinklers and fire detection are being installed and in Unit 2 Reactor Building, cable separation of more than 20 feet will be maintained, to assure that one train of equipment would be unaffected by a postulated fire.

Upon transfer to the SSF, isolation is provided between the normal operating circuiting and the SSF circuiting. This is true for both the controls and power sources. Since the instrumentation and some equipment is dedicated to i the SSF, the need for isolation does not exist.

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With the design of Catawba's dedicated Standby Shutdown Facility, which meets

. Appendix R criteria, through fire protection features and the non existence of

, associated circuits, an assured shutdown capability exist for an all consuming l fire in a given fire area. . -

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