ML17310A745
| ML17310A745 | |
| Person / Time | |
|---|---|
| Site: | Palo Verde  |
| Issue date: | 11/02/1993 |
| From: | Conway W Arizona Public Service Co (Formerly Arizona Nuclear) |
| To: | NRC/IRM |
| Shared Package | |
| ML17310A746 | List: |
| References | |
| 102-02716-WFC-R, 102-2716-WFC-R, NUDOCS 9311050006 | |
| Download: ML17310A745 (8) | |
Text
ACCEI E
~ED DOCUMENT DIST UTION SYSTEM REGU ZORY INFORMATiON DISTRIBU N SYSTEM (RIDS)
ACCESSION'BR:9311050006 DOC.DATE: 93/ll/02 NOTARIZED: YES DOCKET FACIL:STN-50-528 Palo Verde Nuclear Station, Unit 1, Arizona Publi 05000528 AUTH.NAME AUTHOR AFFILIATION CONWAY,W.F.
Arizona Public Service Co. (formerly Arizona Nuclear Power RECIP.NAME RECIPIENT AFFILIATION Document Control Branch (Document Control Desk)
SUBJECT:
Forwards "Unit 1 SG Insp Rept."
DISTRIBUTION CODE:
A047D COPIES RECEIVED:LTR L ENCL /
SIZE: 9 7 g TITLE: OR Submittal: Inservice/Testing/Relief from ASME Code D
NOTES:STANDARDIZED PLANT 05000528 RECIPIENT ID CODE/NAME PDV LA HOLIAN,B INTERNAL: ACRS NRR/DE/EMEB NUDOCS-ABSTRACT OGC/HDS1 RES/DSIR/EIB EXTERNAL: EGSG BROWN,B NRC PDR COPIES LTTR ENCL 1
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1 RECIPIENT ID CODE/NAME PDV PD TRAN,L AEOD/DSP/ROAB NRR/EMCB OC LFDCB G F 01 EG&G RANSOME,C NSIC COPIES LTTR ENCL 1
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NOTE TO ALL"RIDS" RECIPIENTS:
PLEASE HELP US TO REDUCE WASTEI CONTACT THE DOCUMENT CONTROL DESK, ROOM Pl-37 (EXT. 504-2065) TO ELIMINATEYOUR NAME FROM DISTRIBUTION LISTS FOR DOCUMENTS YOU DON'T NEEDI D
TOTAL NUMBER OF COPIES REQUIRED:
LTTR 24 ENCL 21
1
WILLIAMF. CONWAY EXECUTIVEVICEP4ESIOENT NUCLEA4 Arizona Public Service Company P.O. BOX 53999
~
PHOENIX, ARIZONA85072-3999 102-02716-WFC/RAB/JRP November 2, 1993 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Mail Station P1-37 Washington, D.C. 20555
References:
1)
Letter dated August 19, 1993, from T. E. Murley, Director, Office of Nuclear Reactor Regulation, NRC, to W. F. Conway, Executive Vice President, Nuclear, APS 2)
Letter 102-02654, dated September 29, 1993, from W. F. Conway, Executive Vice President, Nuclear, to USNRC 3)
Letter 102-02710, dated October 27, 1993, from W. F. Conway, Executive Vice President, Nuclear, to USNRC
Dear Sirs:
Subject:
Palo Verde Nuclear Generating Station (PVNGS)
Unit 1 Docket No. STN 50-528 Steam Generator Inspection Report File: 93-056-026 By letter dated August 19, 1993 (Reference 1), the NRC required that Arizona Public Service Company (APS), pursuant to 10CFR50.54(f), submit the results of the Steam Generator Eddy Current inspection at least two weeks prior to restart of the unit and discuss the implications of these results on the other two units and discuss the proposed operating interval until the next inspection.
Enclosed with this letter is the Unit 1 Steam Generator Inspection Report.
The Steam Generator Inspection Plan for Unit 1 was submitted to the NRC by Reference 2 and a revised inspection plan was submitted by Reference 3.
The current inservice eddy current testing (ECT) was conducted using both bobbin coil probe and motorized rotating pancake coil (MRPC) probe.
The inspection found no evidence of axial cracks in the upper hot leg area identified both by analysis and 04(.'C52 931i05000b 93ii02 PDR ADQCK'05000528 PDR'
U. S. Nuclear Regulatory Commission Steam Generator Inspection Report Page 2 inspection during the Unit 2 refueling outage (U2R4).
This inspection did identify volumetric indications, both at the top of tube sheet area and in the upper hot and cold leg areas.
A total of four single volumetric indications (SVI) in the Unit 1 Steam Generators were located in the MRPC arc region and may be indicative of early intergranular attack, however, UT inspection of an accessible SVI did not indicate the existance of a crack.
This supports the conclusion that accelerated upper bundle intergranular stress corrosion cracking, such as that observed in Unit 2, is not present in Unit 1.
The eddy current inspection of the Unit 1 Steam Generators did identify circumferential cracking at the top of the tube sheet expansion transition region of Steam Generator 11 and Steam Generator
- 12. This cracking was characterized as both inside diameter (ID) and outside diameter (OD) initiated.
Ultrasonic testing (UT) methods were used on selected tubes to verify the ECT determination of their ID/OD nature.
The safety significance of the circumferential cracking in Unit 1 is bounded by Regulatory Guide 1.121 analysis and is discussed in the enclosure.
In situ pressure tests were conducted to verify compliance with Regulatory Guide 1.121 requirements.
Regulatory Guide 1.121 limits will not be exceeded in one cycle of operation given the observed crack sizes.
Based on the Steam Generator Tube Rupture Analysis and the assessments contained in the enclosure to this letter, operation of Unit 1 for a full cycle would not constitute a safety concern.
APS is prepared to discuss this inspection report with you during the upcoming meeting which is scheduled for November 9, 1993, in Rockville, Maryland. Should you have any questions, please contact Richard A. Bernier at (602) 393-5882.
Sincerely, WFC/JRP/Id Enclosure cc:
B. H. Faulkenberry B. E. Holian J. A. Sloan-
t,'
STATE OF ARIZONA
)
) ss.,
COUNTY OF MARICOPA )
I, W. F. Conway, represent that I am Executive Vice President - Nuclear, that the foregoing document has been signed by me on behalf of Arizona Public Service Company with full authority to do so, that= I have read such document and know its contents, and that to the best of my knowledge and belief, the statements made therein are true and correct.'.
F. Conway Sworn To Before Me This Z Day Of DVENk6, 1993.
Notary Public My Commission Expires MyCommission Expires June12,1997
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