ML17306A812
| ML17306A812 | |
| Person / Time | |
|---|---|
| Site: | Palo Verde  |
| Issue date: | 06/26/1992 |
| From: | Conway W ARIZONA PUBLIC SERVICE CO. (FORMERLY ARIZONA NUCLEAR |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| 102-02185-WFC-G, 102-2185-WFC-G, TAC-M77649, NUDOCS 9207070314 | |
| Download: ML17306A812 (6) | |
Text
ACCELERATED D TRJBUTION DEMONSTRATION SYSTEM REGULAT.iY INFORMATION DISTRIBUTIO YSTEM (RIDS)
ACCESSION NBR:9207070314 DOC.DATE: 92/06/26 NOTARIZED: NO DOCKET FACIL:."TN-50-528 Palo Verde Nuclear Station, Unit 1, Arizona Publi, 05000528 ATN-50-529 Palo Verde Nuclear Station, Unit 2, Arizona Publi 05000529'TN-50-530 Palo Verde Nuclear Station, Unit 3, Arizona Publi 05000530 AUTH.NAME AUTHOR AFFILIATION CONWAYFW.F.
Arizona Public Service Co. (formerly Arizona Nuclear Power RECIP.NAME RECIPIENT AFFILIATION Document Control Branch (Document Control Desk)
SUBJECT:
Discusses monitoring
& evaluation of containment hydrogen monitors. Hydrogen analyzers will not be replaced since exiting analyzers comply w/containment hydrogen monitoring licensing bases.
DISTRIBUTION CODE:
AOOID COPIES RECEIVED:LTR J ENCL 0 SIZE:
TITLE: OR Submittal: General Distribution R
D NOTES:STANDARDIZED PLANT Standardized plant.
Standardized plant.
05000528 A
05000529 05000530 RECIPIENT ID CODE/NAME PD5 LA TRAMMELLFC INTERNAL: ACRS NRR/DET/ESGB NRR/DST 8E2 NRR/DST/SICB8H7 NUDOCS-ABSTRACT OGC/HDS1 RES/DSIR/EIB EXTERNAL: NRC PDR COPIES LTTR ENCL RECIPIENT ID CODE/NAME PD5 PD THOMPSON,M NRR/DET/ECMB 7D NRR/DOEA/OTSB11 NRR/DST/SELB 7E NRR/DST/SRXB 8E OC LFMB REG FILE 01 NSIC COPIES LTTR ENCL D
D NOTE TO ALL"RIDS" RECIPIENTS'LEASE HELP US TO REDUCE WASTE! CONTACTTHE DOCUMENT CONTROL DESK, ROOM Pl-37 (EXT. 20079) TO ELIMINATEYOUR NAME FROM DISTRIBUTION LISTS FOR DOCUMENTS YOU DON'T NEED!
D D
TOTAL NUMBER OF COPIES REQUIRED:
LTTR 26 ENCL
~M t
WILLIAMF. CONWAY EXECUTIVEVICEPRESIDENT NUCLEAR Arizona Public Service Company P.O. BOX 53999
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PHOENIX, ARIZONA85072-3999 102-02185-WFC/GAM June 26, 1992 U. S. Nuclear Regulatory Commission ATTN: Document Control Desk Mail Station P1-37 Washington, DC 20555
References:
1:
Letter 161-03863-WFC/GAM, dated April9, 1991, from W. F. Conway, Executive Vice President, Nuclear, APS, to Document Control Desk, NRC, "Containment Hydrogen Analyzers" 2:
Letter dated October 10, 1991, from C.
M. Thompson, Project
- Manager, Office of Nuclear Reactor Regulation,
- NRC, to W. F. Conway, Executive Vice President, Nuclear, APS, "Containment Hydrogen Monitor Response Time (TAC No. 77649)"
Dear Sirs:
Subject:
Palo Verde Nuclear Generating Station (PVNGS)
Units 1,2, and 3 Docket Nos. STN 50-528/529/530 Containment Hydrogen Analyzers File: 92-056-026 Arizona Public Service Company (APS) previously reported (in Reference
- 1) that the PVNGS Unit 3, Train A, containment hydrogen analyzer did not reliably provide continuous indication within 30 minutes after activation, as specified in the PVNGS Updated Final Safety Analysis Report Section 18.ll.F.1.6.
In order to resolve that deficiency, APS stated that maintenance was being evaluated to improve the analyzer's response time, and that the hydrogen analyzers were scheduled to be replaced during the fourth refueling outages of each PVNGS unit.
Additionally, APS stated that time-response monitoring of the analyzers would be made a formal part of the monthly operations surveillance test to ensure that there is no further increase in response times.
The NRC Staff acknowledged those actions in Reference 2.
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U. S. Nuclear Regulatory Commission ATTN: Document Control Desk Containment Hydrogen Analyzers Page 2 As a result of the evaluation of hydrogen analyzer maintenance, analyzer maintenance procedures have been extensively revised by APS, utilizing the support of the vendor.
The hydrogen analyzer vendor also provided on-site assistance in the implementation of the revised procedures.
Troubleshooting of the Unit 3, Train A hydrogen analyzer revealed a tom diaphragm, which was promptly replaced.
In addition, APS Engineering reviewed the hydrogen analyzer loop accuracy calculation and revised it to include uncertainties that were not previously addressed.
Since these actions were taken, the performance and reliabilityofthe hydrogen analyzers have improved considerably.
Routine testing of the hydrogen analyzers has demonstrated that all of the analyzers, including Unit 3, Train A, consistently meet the licensing bases requirement to provide continuous indication within 30 minutes after activation.
Because the hydrogen analyzers have exhibited improved performance and reliability, APS has determined that it willnot be necessary to replace them. The existing hydrogen analyzers comply with the containment hydrogen monitoring licensing bases requirements.
In addition, engineering evaluations of available replacement hydrogen analyzers have shown that they may not offer cost effective performance and reliability improvements over the existing analyzers.
APS will continue to monitor hydrogen analyzer performance and reliability, and willcontinue to take actions necessary to assure compliance with the licensing bases requirements.
If you have any questions regarding this submittal, please contact Thomas R. Bradish of my staff at (602) 393-5421.
Sincerely, WFC/GAM/pmm cc:
J. B. Martin D. H. Coe A. C. Gehr A. H. Gutterman
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