ML17333A732
| ML17333A732 | |
| Person / Time | |
|---|---|
| Site: | Cook  |
| Issue date: | 04/09/1996 |
| From: | Reinhart M NRC (Affiliation Not Assigned) |
| To: | Fitzpatrick E INDIANA MICHIGAN POWER CO. |
| Shared Package | |
| ML17333A734 | List: |
| References | |
| TAC-M94942, NUDOCS 9701150015 | |
| Download: ML17333A732 (4) | |
Text
CATEGORY 2 REGULA INFORMATION DISTRIBUTIO YSTEM (RIDS)
ACCESSION NBR:9701150015 DOC.DATE: 96/04/09 NOTARIZED: NO-DOCKET FACIL:50-315 Donald C.
Cook Nuclear Power Plant, Unit 1, Indiana M
05000315 50-316 Donald C.,Cook nuclear Power Plant, Unit 2, Indiana M
05000316 AUTH.NAME AUTHOR AFFQLZATION REINHART,M.
RECIP.NAME RECIPIENT AFFILIATION FITZPATRICK,E.
SUBJECT:
Forwards SE accepting use of embedded flaw repair method using procedures
& processes outlined in WCAP-14519 as alternative to ASME Code requirements.
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50 Docket (PDR Avail)
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1 RECIPIENT ID CODE/NAME NUDOCS-ABSTRACT NRC PDR COPIES LTTR ENCL 1
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NOTE TO ALL "RIDS" RECIPIENTS:
PLEASE HELP US TO REDUCE WASTE. TO HAVE YOUR NAME OR ORGANIZATION REMOVED FROM DISTRIBUTION LISTS OR REDUCE THE NUMBER OF COPIES RECEIVED BY YOU OR YOUR ORGANIZATION, CONTACT THE DOCUMENT CONTROL DESK (DCD)
ON EXTENSION 415-2083 TOTAL NUMBER OF COPIES REQUIRED:
LTTR 4
ENCL 4
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t UNITED STATES NUCLEAR REGUlATORY COMMISSION WASHINGTON, D.C. 20SRHXO1 April 9, 1996 Hr. E. E. Fitzpatrick, Vice President Indiana Michigan Power Company c/o American Electric Power Service Corporation 1 Riverside Plaza
- Columbus, Ohio 43215
SUBJECT:
D.C.
COOK, UNITS 1 AND 2, REACTOR VESSEL HEAD PENETRATIONS, ALTERNATIVE WELD REPAIR METHOD (TAC NOS.
H94942 AND M94943)
Dear Hr. Fitzpatrick:
By letter dated March 12,
request to the NRC staff to use an alternative repair method if flaws that exceed the acceptance criteria are found during the vessel head penetration (VHP) reinspection during the upcoming refueling outage at the Donald C.
Cook Nuclear Plant (D.C. Cook), Units 1 and 2.
The VHP reinspections are being conducted because indications attributed to primary water stress corrosion cracking were found in VHP 75 during the inspection of the VHPs at D.C.
Cook during the 1994 refueling outage.
In addition to VHP 75, several additional VHPs will also be examined to ensure that no new indications are present.
Westinghouse performed an evaluation that indicated, despite the presence of the indications, the reactor could be operated for one cycle and that the indications would not grow to a size that would exceed the acceptance criteria before the reinspection.
The results of the VHP reinspections at D.C.
Cook will be fed into the Westinghouse model to determine what additional inspections are indicated at U.S. nuclear power plants.
Flaws in a VHP in a pressurized water reactor (PWR) were initially detected at a French plant in 1991.
Since that discovery, flaws have been discovered in VHPs at numerous plants around the world and in the U.S.
The Nuclear Energy Institute (NEI) coordinated an effort by the U.S.
PWR owners group.
The owners groups submitted safety assessments to the NRC staff that indicated if flaws were initiated in VHPs they would predominately be short, axial cracks.
As the cracks grow, the VHP would leak before breaking and the leakage would be detected.
The NRC staff reviewed the safety assessments and agreed with the conclusions.
NEI submitted proposed acceptable flaw size criteria to the NRC staff and the NRC staff accepted the criteria with comments.
An evaluation of your request to use the alternative weld repair method is provided in the enclosure.
A safety evaluation of the Mestinghouse Topical
- Report, WCAP-14519, "RV Closure Head Penetration Tube ID Meld Overlay Repair,"
in which the repair method is discussed, was issued in a letter to Virginia Electric and Power Company dated February 5, 1996.
The NRC staff concludes that the use of the embedded flaw repair method using the procedures and processes outlined in WCAP-14519 is an acceptable alternative to the ASIDE Code requirements.
The use of the embedded flaw repair method has previously been approved for the Virginia Electric and Power Company North Anna Plant, Unit 1.
The proposed alternative for the repair of g40040 9701150015 9b0409 PDR ADOCK 05000315 P
h
E. Fitzpatrick April 9, 1996 flaws exceeding the acceptance criteria for the D.C.
Cook Units 1 and 2
reactor vessel head penetrations is authorized as requested pursuant to IQ CFR 50.55a(a)(3)(i).
This alternative will provide an acceptable level of quality and safety.
The staff's evaluation and conclusions are contained in the enclosed safety evaluation.
Sincerel Docket Nos.
50-315 and 50-316
Enclosure:
Safety Evaluation cc w/encl:
See next page Hark einhart, Acting Director Project Directorate III-1 Division of Reactor Projects - III/IV Office of Nuclear Reactor Regulation