ML17306B337

Special Rept 2-SR-93-001:on 930314,control Room Personnel Manually Tripped Reactor Due to Rapid Decrease in Pressurizer Heaters.Personnel Commenced Controlled Plant Cooldown.Unit Remains Shut Down for Further Investigation

ML17306B337
Person / Time
Site:	Palo Verde
Issue date:	03/15/1993
From:	James M. Levine ARIZONA PUBLIC SERVICE CO. (FORMERLY ARIZONA NUCLEAR
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
192-00834-JML-T, 192-834-JML-T, 2-SR-93-001, 2-SR-93-1, NUDOCS 9303190182
Download: ML17306B337 (8)

Text

ACCELERA. <D DOCUMENT DIST BUTION SYSTEM REGUL Y INFORMATION DISTRIBUTI SYSTEM (RIDS)

DEACCESSION NBR:9303190182 DOC.DATE: 93/03/15 NOTARIZED: NO DOCKET FACIL STN-50-529 Palo Verde Nuclear Station, Unit 2, Arizona Publi 05000529 AUTH. NAME AUTHOR AFFILIATION LEVINEgJ.M. Arizona Public Service Co. (formerly Arizona Nuclear Power RECIP.NAME RECIPIENT AFFILIATION Document Control Branch (Document Control Desk)

SUBJECT:

Special rept 2-SR-93-001:on 930314,control room personnel manually tripped reactor due to rapid decrease in pressurizer heaters. Personnel commenced controlled plant cooldown.Unit remains shut down for further investigation.

D1STRIBUTION CODE: IE22D COPIES RECEIVED:LTR ENCL SIZE:

TITLE: 50.73/50.9 Licensee Event Report '(LER), Incident Rpt, etc.

NOTES:Standardized plant. 05000529 RECIPIENT COPIES RECIPIENT, COPIES ID CODE/NAME LTTR ENCL ID CODE/NAME LTTR ENCL PD5 LA 1 1 PD5 PD 1 1 TRAMMELLgC 1 1 TRAN,L 1 1 INTERNAL: ACNW 2 2 ACRS 2 2 AEOD/DOA 1 1 AEOD/DSP/TPAB 1 1

~

AEOD/ROAB/DSP 2 2 NRR/DE/EELB 1 1 NRR/DE/EMEB 1 1 NRR/DORS/OEAB 1 1 NRR/DRCH/HHFBHE 1 1 NRR/DRCH/HICB 1 1 NRR/DRCH/HOLB 1 1 NRR/DRIL/RPEB 1 1 NRR/DRSS/PRPB 2 2 NRR/DSSA/SPLB 1 1 NRR/DSSA/SRXB 1 1 6% 1 1 RES/DSIR/EIB 1 1 RGN5 FILE Ol 1 1 EXTERNAL: EGSG BRYCEgJ.H 2 2 L ST LOBBY WARD 1 1 NRC PDR 1 1 NSIC MURPHY,G.A 1 1 NSIC POOREiW. 1 1 NUDOCS FULL TXT 1 1 NOTE TO ALL"RIDS" RECIPIENTS:

PLEASE HELP US TO REDUCE WASTETH CONTACI'HE DOCUMENT CONTROL DESK, ROOM Pl-37 (EXT. 504-2065) TO ELIMINATEYOUR NAME FROM DISTRIBUTION LISTS FOR DOCUMENTS YOU DON'7 NEED)

TOTAL NUMBER OF COPIES REQUIRED: LTTR 33 ENCL 33

0 Arizona Public Service Company PALO VERDE NUCLEAR GENERATING STATION P.O. BOX 52034 ~ PHOENIX. ARIZONA 85072-2034 JAMES M LEVINE VICE PAKSIOENT 192-00834-JML/TRB/NLT NUCI.EAII PrIODUCTION March 15, 1993 U. S. Nuclear Regulatory Commission ATTN: Document Control Desk Mail Station P1-37 Washington, DC 20555

Subject:

Palo Verde Nuclear Generating Station (PYNGS)

Unit 2 Docket No. STN 50-529 (License No. NPF-51)

Special Report 2-SR-93-001 File: 93-020-404 Enclosed please find Special Report 2-SR-93-001 prepared and submitted pursuant to PVNGS Emergency Plan Implementing Procedure (EPIP-04), "Alert, Site Area and General Emergency Implementing Actions." This report discusses a condition requiring the declaration of an Alert due to Reactor Coolant System leakage greater than 44 gallons per minute.

lf you have any questions, please contact Thomas R. Bradish, Manager, Nuclear Regulatory Affairs at. (602) 393-5421, Sincerely, l>

JML/TRB/NLT/nit Enclosure cc: W. F. Conway (all with enclosure)

J. B. Martin J. A. Sloan 9303190i82 9303i5 PDR S

ADOCK 05000529 PDR g gf I

ENCLOSURE PALO VERDE NUCLEAR GENERATING STATION UNIT 2 ALERT DOCKET NO. 50-529, LICENSE NO. NPF-51 SPECIAL REPORT 2-SR-93-001

PALO VERDE NUCLEAR GENERATING STATION UNIT 2 ALERT DOCKET NO. 50-529, LICENSE NO. NPF-51 SPECIAL REPORT 2-SR-93-001 This Special Report is being provided pursuant to PVNGS Emergency Plan Implementing Procedure (EPIP-04), "Alert, Site Area and General Emergency Implementing Actions" to report a condition requiring the declaration of an Alert for Palo Verde Unit 2 at approximately 0502 MST on March 14, 1993. The Alert was terminated at approximately 0115 MST on March 15, 1993.

On March 14, 1993, at approximately 0435 MST, Palo Verde Unit 2 was operating at approximately 98 percent power in Mode 1 (POWER OPERATION) when Control Room personnel noticed pressurizer pressure and level were decreasing and energized the pressurizer heaters. At approximately 0447 MST, Control Room personnel manually tripped the reactor due to a rapid decrease in pressurizer level. At approximately, 0448 MST, valid actuations of the Safety Injection Actuation System and the Containment Isolation Actuation System were received and at approximately 0458 MST, a Notification of Unusual Event was declared in accordance with Emergency Plan Implementing Procedure (EPIP-02), "Emergency Classification."

At approximately 0502 MST, it was determined that Reactor Coolant System (RCS) leakage was greater than 44 gallons per minute and the emergency classification was upgraded to an Alert in accordance with EPIP-02. Control Room personnel entered emergency procedures, as required, to diagnose and mitigate the event. At approximately 0514 MST, the appropriate state and local agencies were notified of the condition requiring the declaration of an Alert (i.e., RCS leakage greater than 44 gallons per minute). The Nuclear Regulatory Commission (NRC) Operations Center was notified at approximately 0530 MST.

At approximately 0603 MST, Control Room personnel commenced a controlled plant cooldown. At approximately 0640 MST, the Control Room Supervisor diagnosed a Steam Generator Tube Rupture in Steam Generator 2.

At approximately 0115 MST on March 15, 1993, the Alert was terminated in accordance with EPIP-04. By approximately 01 37 MST, the appropriate state local agencies and the NRC Operations Center were notified of the termination of the Alert.

Unit 2 will remain in shutdown conditions and will transition into a scheduled refueling outage. Further investigation into the circumstances surrounding this event is being performed in accordance with the APS incident Investigation Program. The results of the investigation will be reported pursuant to 10CFR50.73.