ML17306B423

Suppl 1 to Special Repts 2-SR-92-004 & 3-SR-92-006:on 921222 Unit 2 PASS Declared Inoperable Due to Failure of Containment Air Flow Indicator.On 921217,Unit 3 PASS Declared Inoperable.Equipment Replaced & Sample Obtained

ML17306B423
Person / Time
Site:	Palo Verde
Issue date:	04/24/1993
From:	LEVINE J M ARIZONA PUBLIC SERVICE CO. (FORMERLY ARIZONA NUCLEAR
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
192-00838-JML-T, 192-838-JML-T, 2-SR-92-004, 2-SR-92-4, 3-SR-92-006, 3-SR-92-6, NUDOCS 9305050113
Download: ML17306B423 (19)

Text

ACCELER ED DOCUMENT DISTR IBUT1ON SYSTEM REGUL~ORY INFORMATION DISTRIBUT.SYSTEM (RIDE)ACCF(SSION NBR:9305050113 DOC.DATE: 93/04/24 NOTARIZED:

NO DOCKET FACIL:STN-50-529 Palo Verde Nuclear Station, Unit,2,arizona-Pub1i.,05000529 STN-50-530 Palo Verde Nuclear Station, Uiii't'3,Arizona Publi 05000530 AUTH.NAME AUTHOR AFFILIATION LEVINE,J.M.

Arizona Public Service Co.(formerly Arizona Nuclear Power RECIP.NAME RECIPIENT AFFILIATION Document.-Control Branch (Document Control Desk)I i

SUBJECT:

Suppl 1 to Special.Repts 2-SR-92-.004&.3-SR-92-006:on 921222 unit 2 PASS declared inoperable due to failure of containment air flow indicator.

On 921217,Unit 3 PASS declared inoperable.

Equipment replaced&sample obtained.DISTRIBUTION CODE: IE22D COPIES RECEIVED:LTR ENCL SIZE: TITLE: 50.73/50.9 Licensee Event Report (LER), ncident Rpt, etc.NOTES:Standardized plant.Standardized plant.05000529 05000530 RECIPIENT ID CODE/NAME PDV LA TRAMMELL,C INTERNAL: ACNW'AEOD/DOA AEOD/ROAB/DSP NRR/DE/EMEB NRR/DRCH/HHFB NRR/DRCH/HOLB NRR/DRSS/PRPB NRR/DSSA/SRXB RES/DSIR/EIB EXTERNAL: EG&G BRYCE,J.H NRC PDR NSIC POOREFW.COPIES LTTR ENCL 1 1 1 1 2 2 1 1 2 2 1 1 1 1 1 1 2 2 1 1 1 1 2 2 1 1 1 1 RECIPIENT ID CODE/NAME PDV PD TRAN,L ACRS AEOD/DSP/TPAB NRR/DE/EELB NRR/DORS/OEAB NRR/DRCH/HICB NRR/DRIL/RPEB NR SPLB EG FI E 02 R ILE 01 L ST LOBBY WARD NSIC MURPHYiG~A NUDOCS FULL TXT COPIES LTTR ENCL 1 1 1-1 2 2 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1-1 1 1 NOTE TO ALL"RIDS" RECIPIENTS PLEASE HELP US TO REDUCE WASTE!CONTACT fHE DOCUMENT COiNTROL DESK.ROOM Pl-37 (EXT.504-2065)TO ELIMINATE YOUR NAME FROM DISTRIBUTION LISTS FOR DOCUMENTS YOU DON'T iNEED!TOTAL NUMBER OF COPIES REQUIRED: LTTR 33 ENCL 33 I" ll Arizona Public Service Company PALO VERDE NUCLEAR GENERATING STATION P.O.BOX 52034~PHOENIX, ARIZONA 85072-2034 JAMES M LEVINE VICE PRES'lOENT NUCLEAR PAODUC1ION 192-00838-JML/TRB/KR April 24, 1993 U.S.Nuclear Regulatory Commission Attention:

Document Control Desk Mail Station P1-37 Washington, D.C, 20555

Subject:

Palo Verde Nuclear Generating Station (PVNGS)Units 2 and 3 Docket Nos.STN 50-529 and 50-530 License Nos.NPF-51 and NPF-74 Supplement 1 to Special Reports 2-SR-92-004 and 3-SR-92-006 File: 93-020-404 Enclosed is Supplement 1 to Special Reports 2-SR-92-004 and 3-SR-92-006 prepared and submitted pursuant to Technical Specifications (TS)3.3.3.1 ACTION 28 and TS 6.9.2.Enclosure 1 contains the reports which discuss the Post Accident Sampling System (PASS)being inoperable for greater than seven (7)days in Units 2 and 3.Enclosure 2 contains the cause of the inoperability and the actions to prevent recurrence as determined by our evaluation performed in accordance with the PVNGS Incident investigation Program.A copy of this supplement is being forwarded to the Regional Administrator, NRC Region V.lf you have any questions, please contact T.R.Bradish, Manager, Nuclear Regulatory Affairs at (602)393-5421.-JML/TRB/KR/rv Sincerely,/~(

Enclosures:

1.Special Reports 2-SR-92-004-01 and 3-SR-92-006-01 2.Cause of Post Accident Sampling System Inoperability

, cc: W.F.Conway (all with enclosures)

J.B.Martin J.A.Sloan AAAc A~]9305050ii3 930424 PDR ADQCK 05000529 8 PDR~pvF

ENCLOSURE 1 SPECIAL REPORTS 2-SR-92-004-01 AND 3-SR-92-006-01

PALO VERDE NUCL'EARGENERATING STATION UNIT 2'POST ACCIDENT SAMPLING SYSTEM INOPERABLE GREATER THAN SEVEN DAYS-Docket No.50-529 1 License No.NPF-51 Special Report No.2-SR-92-004-01 INITIAL CONDITIONS:

This Special Report is being submitted pursuant to Technical Specifications (TS)3.3.3.1 ACTION 28 and TS 6.9.2 to report an event in which the Post Accident Sampling System (PASS)was inoperable for a period greater than seven (7)days.The seven-day period for returning PASS to service was exceeded at approximately 0830 MST on December 29, 1992.BACKGROUND INFORMATION'ASS is designed to sample reactor coolant and containment atmosphere under post accident conditions.

The liquid sample portion of the system provides pressurized and depressurized reactor coolant samples as required for analysis.The gas sample portion of the system provides containment atmosphere samples as required for analysis.ACTIONS TAKEN: On December 22, 1992, Palo Verde Unit 2 was in Mode 1 (POWER OPERATION) when Control Room personnel declared PASS inoperable at approximately 0830 MST due to the failure of the containment air flow indicator and the indication of water leakage at the PASS reactor coolant system sample septum.The Preplanned Alternate Sampling Program was initiated in accordance with TS 3.3.3.1 ACTION 28.I The failures were identified during the performance of the TS monthly functional surveillance.

On December 23, 1992, the containment air flow indicator was repaired and tested, On December 24, 1992, troubleshooting commenced to identify the source of the leakage.The troubleshooting involved extensive coordination between Unit 2 Maintenance and Unit 2 Chemistry personnel to simulate system parameters and valve lineups necessary to draw the reactor coolant system pressurized sample.The source of the leakage was difficult to identify and the replacement of multiple valves was required in order to obtain a pressurized sample and declare the system operable.

l I Special Report 2-SR-92-004-01 On January 3, 1993, following restoration of PASS, a pressurized sample was obtained and the acceptance criteria for the monthly functional surveillance requirement was met.The work documents were closed on January 5, 1993.PLANS AND SCHEDULE FOR RESTORING THE SYSTEM TO SERVICE: Following satisfactory completion of repairs and required surveillance testing, PASS was returned to OPERABLE status at approximately 1545 MST on January 5, 1993.

PALO VERDE NUCLEAR GENERATING STATION UNIT 3 POST ACCIDENT SAMPLING SYSTEM INOPERABLE GREATER THAN SEVEN DAYS Docket No.50-530~1 License No.NPF-74 Special Report No.3-SR-92-006-01 INITIAL CONDITIONS:

This Special Report is being submitted pursuant to Technical Specifications (TS)3.3.3.1 ACTION 28 and TS 6.9.2 to report an event in which the Post Accident Sampling System (PASS)was inoperable for a period greater than seven (7)days.The seven-day period for returning PASS to service was exceeded at approximately 1515 MST on December 24, 1992.BACKGROUND INFORMATION:

PASS is designed to sample reactor coolant and containment atmosphere under post accident conditions.

The liquid sample portion of the system provides pressurized and depressurized reactor coolant samples as required for analysis.The gas sample portion of the system provides containment atmosphere samples as required for analysis.ACTIONS TAKEN: On December 17, 1992, Palo Verde Unit 3 was in Mode 1 (POWER OPERATION) when Control Room personnel declared PASS inoperable at approximately 1515 MST following the failure to meet the pressurized sample portion of the acceptance criteria for the monthly functional surveillance requirement.

On December 19, 1992, following troubleshooting, two valves (HV-22 and HV-23)were replaced due to suspected leakage.An additional valve (PSV-101)was replaced when Chemistry technicians could not establish a vacuum on the PASS pressurized sample flask.When Chemistry technicians were unable to obtain the proper flow for the PASS pressurized sample, following troubleshooting, it was discovered that an incorrect actuator was installed during the replacement of HV-22.Following replacement of the actuator, at approximately 1625 MST on December 22, 1992, a pressurized sample was obtained and the acceptance criteria for the monthly functional surveillance requirement was met.

Special Report 3-SR-92-006-01 However, on December 22, 1992, a new revision of the monthly functional surveillance procedure, which included intent changes, became effective and Unit 3 Chemistry management determined that the pressurized portion of the surveillance testing (ST)should be reperformed using the new ST procedure.

PASS failed to meet the pressurized sample portion of the new acceptance criteria for the monthly functional surveillance requirement.

On December 23, 1992, during attempts to reperform the PASS pressurized sample portion of the ST, Chemistry technicians-discovered seat leakage on valve HV-22 and packing leakage on HV-23.Further troubleshooting, performed on December 24, 1992, discovered that HV-22 had been installed backwards.

At approximately 1815 MST on December 24, 1992, the'Preplanned Alternate Sampling Program was initiated in accordance with TS 3.3.3.1 ACTION 28.On December 26, 1992, following replacement of HV-22 and restoration of PASS, a pressurized sample was obtained and the acceptance criteria for the monthly functional surveillance requirement was met.PLANS AND SCHEDULE FOR RESTORING THE SYSTEM TO SERVICE: Following satisfactory completion of repairs and required surveillance testing, PASS was returned to OPERABLE status at approximately 1100 MST on December 26, 1992.

II ENCLOSURE 2 CAUSE OF POST ACCIDENT SAMPLING SYSTEM INOPERABILITY

Special Reports 2-SR-92-004-01 and 3-SR-.92-006-04 CAUSE OF THE INOPERABILITY An evaluation was performed in accordance with the PYNGS Incident Investigation Program.The evaluation identified that several weaknesses existed in the processes used in testing, troubleshooting, and repairing PASS that contributed to delays in returning PASS to an operable status within the seven day period allowed by the TS ACTION statement.

The evaluation determined that these weaknesses have persisted because management attention was not adequately applied to ensure that personnel had the adequate tools and/or training available to restore PASS to an operable status.The following weaknesses were identified by the evaluation:

Inadequate documentation (i.e., system description and technical manuals)and drawings resulted in the development of work documents which did not provide sufficient guidance for troubleshooting and repair for PASS restoration.

2.Chemistry technicians responsible for the operation of PASS had not been expected to possess specific PASS system/component design knowledge required to assist in troubleshooting, thereby impeding their ability to communicate pertinent information to the work group and expedite the return of PASS to an operable status.3.Schedulers, planners, and maintenance technicians had not been expected to possess specific PASS system/component design knowledge, thereby impeding their ability to generate, as well as implement, work documents necessary to return PASS to an operable status.The improper valve installations that occurred during recent PASS repair activities are not only attributable to personnel error or poor work practices, but also to insufficient understanding of PASS 3-way valve orientation and PASS flow paths.4 Due to PASS complexity and restricted access, regular maintenance, troubleshooting, and repairs are time-consuming.

This weakness has been discussed, however, an evaluation to examine PASS configuration as well as component reliability to determine if practical upgrades to facilitate PASS maintenance activities were feasible and cost beneficial was not initiated.

The items discussed above are indicative of a lack of management attention to the longstanding problems with PASS.To address these issues, the following corrective actions are being implemented to ensure PASS is restored to an operable status in a timely manner.1.A memo was distributed to Site Chemistry personnel stating that PASS troubleshooting and repair is to be coordinated with the responsible work group rather than through the system engineer.

<<'pecial Reports".-2-SR-:92-004 01 and 3-.SR-92-006-01 2.Existing training for chemistry technicians, maintenance technicians, schedulers, and planners will be evaluated and upgraded as necessary to ensure that enhanced PASS system/component information is incorporated.

The evaluation is expected to be completed by June 30, 1993.3.APS Engineering will review past corrective maintenance documents to determine if PASS component reliability problems exist.The review is expected to be completed by July 30, 1993.4.APS Engineering will evaluate the current PASS configuration and determine the practicality of design upgrades to facilitate future PASS maintenance activities.

The evaluation is expected to be completed by July 30, 1993.5.The development of a model work document, which should significantly reduce the process to troubleshoot and repair PASS, is expected to be completed by Octobel 30, 1993.In addition, a review of existing PASS documentation and drawings and their accessibility will be performed in parallel with the development of the model work order.

I l