ML17352B012
| ML17352B012 | |
| Person / Time | |
|---|---|
| Site: | Turkey Point  |
| Issue date: | 01/31/1995 |
| From: | Plunkett T FLORIDA POWER & LIGHT CO. |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| L-95-28, NUDOCS 9502070106 | |
| Download: ML17352B012 (8) | |
Text
PR.IC)R.I EY' ACCELERATED RIDS PROCESSING REGULATORY INFORMATION DXSTRIBUTION SYSTEM (RIDS)
ACCESSXON NBR:9502070106 DOC.DATE: 95/01/31 NOTARIZED: NO DOCKET g FACIL:50-250 Turkey Point Plant, Unit 3, Florida Power and Light C 05000250 50-251 Turkey Point Plant, Unit 4, Florida Power and Light C 05000251 AUTH.NAME AUTHOR AFFILIATXON PLUNKETT,T.F.
Florida Power 6 'Light Co.
RECIP.NAME RECIPIENT AFFILIATION Document Control Branch (Document Control Desk)
SUBJECT:
Documents util response to concerns re SG mechanical tube plugs fabricated from thermally treated Alloy 600.
DISTRXBUTION CODE: A001D COPIES RECEIVED:LTR ENCL SIZE:
TITLE: OR Submittal: General Distribution NOTES RECXPIENT ID CODE/NAME PD2-2 LA CROTEAU,R INTERN~If:~FILE CENTER P1 NRR/D'SSA/SPEB NUDOCS-ABSTRACT
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1 RECIPIENT ID CODE/NAME PD2-2 PD NRR/DRCH/HICB NRR/DSSA/SRXB OGC/HDS3 NRC PDR COPIES LTTR ENCL 1
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1 iNOTE TO ALL"RIDS" RECIPI EYTS:
PLEASE HELP VS TO REDUCE O'ASTE! COYTACTTHE DOCL'i!EiTCONTROL DESk, ROO!iI P I-37 (EAT, 504-~OS3
) TO F LIliI!ATE YOI'R WAX'IL' f<OXI DISTRIBUTION LIS'I'S I'OR DOCL'MEi'I'SYO!.'ON"I'L'ID!
TOTAL NUMBER OF COPIES REQUIRED:
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U.S. Nuclear Regulatory Commission Attn: Document Contxol Desk Washington, D.
C.
20555 Re:
Turkey Point Units 3 and 4
Docket Nos.
50-250 and 50-251 Allo 600 Steam Generator Mechanical Tube Plu s
The purpose of this letter is to document Florida Power and Light's (FPL) response to concerns regarding steam generator mechanical tube plugs fabricated from thermally treated (TT) Alloy 600.
On December 22,
- 1994, the NRC held a meeting with the Westinghouse Owners Group (WOG) and industry representatives to discuss recent operating experience affecting the predicted service life of steam generator mechanical tube plugs fabricated from TT Alloy 600 and supplied by Westinghouse.
The NRC has concluded that the issue does not represent an immediate safety concern, but has informally requested that the industry take a proactive approach to resolving this issue.
In response to this request, the WOG Issues Review Group has identified several items to be addressed by each utility.
Attached is FPL's response to the items identified by the WOG, for Turkey Point Units 3 and 4
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Should there be any questions, please contact us.
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Very truly,yours, T. F. Plunkett Vice President Turkey Point Plant TFP/OIH cc:
Stewart D. Ebneter, Regional Administrator, Region II, USNRC T. P.
- Johnson, Senior Resident Inspector,
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c Attachment to L-95-28 Page 1 of 3 TURKEY POINT UNITS 3 AND 4 ALLOY 600 THERMALLY TREATED STEAM GENERATOR MECHANICAL TUBE PLUGS BACKGROUND On December 22,
- 1994, the NRC held a meeting with the Westinghouse Owners Group (WOG) and industry representatives to discuss recent operating experience affecting the predicted service life of steam generator mechanical tube plugs fabricated from thermally treated (TT)
Alloy 600 and supplied by Westinghouse.
The NRC has informally requested that the industry take a proactive approach to resolving this issue.
By letter OG-94-107, from Thomas V. Greene, WOG Vice Chairman, to Westinghouse Owners Group Primary Representatives, dated December 30,
- 1994, the WOG Issues Review Group identified several items to be addressed by each utility in response to NRC's request.
The following is FPL's response to the items identified by the WOG for Turkey Point Units 3 and 4.
ITEM 1 Identify the number of Westinghouse mechanical plugs manufactured from Alloy 600 TT material present in your steam generators that have not been either changed out or repaired.
FPL RESPONSE The following table summarizes the number of Westinghouse mechanical plugs manufactured from Alloy 600 TT currently installed in the Turkey Point Units 3 and 4 steam generators.
STEAM GENERATOR 3A 3B 3C 4B 4C HOT LEG 17 14 COLD LEG 20
e 4
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Attachment to L-95-28 Page 2 of 3 ITEM 2 Reaffirm that operation of your plant with the identified plugs does not represent a safety issue.
FPL RESPONSE The basis for the Justification For Continued Operation (JCO) with TT Alloy 600 steam generator mechanical plugs is documented in WCAP-
- 12244, "Steam Generator Tube Plug Integrity Summary Report, " dated April 1989, and subsequent revisions.
The JCO is based on the following factors:
a)
Low probability of a Plug Top Release (PTR) event b)
The population of tubes which may perforate as a result of plug top release is limited c) Should perforation occur following PTR, the primary to secondary leakage consequences are limited d) There is a very low likelihood that multiple plugs could be in a condition that would be capable of resulting in PTR e)
The plant Emergency
Response
Guidelines are adequate to bring the plant to safe shutdown following PTR All of the above factors are still applicable to Turkey Point Units 3
and 4, therefore, the JCO is still valid.
Additionally, since all of the subject tube plugs are pre-operational installations for manufacturing degraded
- tubes, they are not expected to result in primary to secondary leakage should plug cracking occur.
ITEM 3 A commitment to evaluate and assess the impact of the Addendum 3 to WCAP-12244, to be issued by Westinghouse by January 31,
- 1995, on your existing action plan for addressing mechanical plug corrosion provided to the NRC in response to NRC Bulletin 89-01 and its supplements.
FPL RESPONSE FPL has performed remote tube sheet visual inspections of all installed steam generator tube plugs, regardless of manufacture, at each refueling outage subsequent to the issuance of NRC Bulletin 89-01.
These inspections have resulted in the removal and replacement of 1 suspect hot leg Westinghouse mechanical tube plug.
The suspect plug was provided to Westinghouse for evaluation.
The cause of leakage was determined to be inadequate installation.
In addition, steam generator tube inspections for Turkey Point Units 3 and 4, performed during the 1994 refueling outages, did not identify any degraded tube plugs.
The impact of Addendum 3 has already been assessed for applicability at the Turkey Point Units 3 and 4 steam generators.
All subject hot leg plugs are scheduled to be removed and replaced during the next scheduled refueling outages which are currently scheduled for September 1995 for Unit 3, and March 1996 for Unit 4.
Preliminary
Attachment to L-95-28 Page 3 of 3 lifetimes for cold leg plugs, to be published in the next revision to WCAP-12244, would require repair/replacement of the subject cold leg plugs in approximately the year 2000 'old leg tube plugs installed in the Turkey Point steam generators will be repaired/replaced during the scheduled zefueling outages prior to the recommended lifetimes.
ITEM 4 A commitment to issue to the NRC a schedule and revised action plan for your plant in addressing this issue 30 days prior to your next scheduled outage.
FPL RESPONSE FPL plans to remove and replace the subject hot leg tube plugs during the next refueling outages for Turkey Point Units 3 and 4 which currently scheduled foz September 1995 foz Unit 3, and March 1996 for Unit 4.
Cold leg tube plugs will be repaired/replaced in accordance with the recommended dates to be published in the next revision to WCAP-12244.
FPL will notify the NRC of any changes to this schedule.
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