ML20141G669
| ML20141G669 | |
| Person / Time | |
|---|---|
| Site: | Millstone  |
| Issue date: | 04/18/1986 |
| From: | Charemagne Grimes Office of Nuclear Reactor Regulation |
| To: | Opeka J NORTHEAST NUCLEAR ENERGY CO. |
| References | |
| NUDOCS 8604230486 | |
| Download: ML20141G669 (3) | |
Text
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April 18,1986.
Docket No.:
50-245 DISTRIBUTION (Docket FHefh s
Mr. John F. Opeka, Senior Vice President NRC PDR' ACRS (10)
Nuclear Engineering and Operations Local PDR BGrimes Northeast Nuclear Energy Company SECY LJHarmon Post Office Sox 270 PAnderson CMiles Hartford, Connecticut 06141-0270 FMiraglia JPartlow OELD ISAP R/f
Dear Mr. Opeka:
DCrutchfield Edordan JShea
SUBJECT:
MAIN TURBINE INSPECTION INTERVAL Re:
Millstone Nuclear Power Station, Unit 1 By letters dated December 13 and December 20, 1985, you informed the staff of the preliminary results from the low pressure turbine inspection during the 1985 refueling outage at Millstone Nuclear Power Station, Unit 1.
The staff has completed its initial review of the results and our finding is set forth below.
During the scheduled inspection of the "B" low pressure turbine, you identified a 1.4-_ inch long crack in the radial direction above the keyway on the Number 4 generator end wheel. This is an increase of about 1.2 inches over the length of the same indication measured during the scheduled inspection in 1980.
The General Electric Company (GE), the manufacturer of the turbine, had analyzed the results of both inspections and had recommended a 21 month inspection interval based on an acceptable analytical procedurt. Later, GE changed the recommended inspection interval from 21 months to 1.2 years (about 15 months).
GE's recommended inspection interval ensures that the probability of turbine damage and subsequent missile generation remains acceptably low.
Because the unit has only been operated for about three months since the December 1985 restart, the staff concludes that Millstone Unit 1 may continue to operate at this time eithout affecting the public safety, and that the licensee should follow Cc's inspection interval of 1.2 years.
However, during a telephcne conversation on January 10, 1986, your representative committed to submit a turbine failure analysis by June 30, 1986 to justify a longer inspection interval. As a part of that submittal, you should provide a basis for deviating from GE recommended inspection interval.
-Sincerely, i
i Original signed by:
C. I. Grimes
% 42 g g g % $45 Christopher I. Grimes, Director PDR G
Integrated Safety Assessment Project Directorate Division of PWR Licensing - B cc: See Next Page ISAPD:DPL-B PAnderson@B ISAPD:DPL-ISAPD:DPL
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April 18,1986 Docket No.: 50-245 Mr. John F. Opeka, Senior Vice President Nuclear Engineering and Operations Northeast Nuclear Energy Company Post Office Box 270 Hartford, Connecticut 06141-0270~
Dear Mr. Opeka:
SUBJECT:
MAIN TURBINE INSPECTION INTERVAL Re:
Millstone Nuclear Power Station, Unit 1 By letters dated December 13 and December 20, 1985, you informed the staff of the preliminary results from the low pressure turbine inspection during the 1985 refueling outage at Millstone Nuclear Power Station, Unit 1.
The staff has completed its initial review of the results and our finding is set forth below.
During the scheduled inspecticn of the "B" low pressure turbine, you identified a 1.4-inch long crack in the radial direction above the keyway on the Number 4 generator end wheel.
This is an increase of about 1.2 inches over the length of the same indication measured during the scheduled inspection in 1980.
The i
General Electric Company (GE), the manufacturer of the turbine, had analyzed the results of both inspections and had recommended a 21 month inspection interval based on an acceptable analytical procedure. Later, GE changed the reconinended inspection interval from 21 months to 1.2 years (about 15 months).
GE's recommended inspection interval ensures that the probability of turbine damage and subsequent missile generation remains acceptably low.
Because the unit has only been operated for about three months since the December 1985 restan, the staff concludes that Millstone Unit 1 may continue to operate at this t w without affecting the public safety, and that the licensee should follow GE's inspection interval of 1.2 years.
However, during a telephone conversation on January 10, 1986, your representative committed to submit a turbine failure analysis by June 30, 1986 to justify a longer inspection interval. As a part of that submittal, you should provide a basis for deviating from GE reconenended inspection interval.
Sincerely,
.e Ad AyAhA 1 -
Christopher I. Grimes, Director Integrated Safety Assessment Project Directorate Division of PWR Licensing - B cc: See Next Page
Mr. John F. Opeka Millstone Nuclear Power Station Northeast NLclear Energy Company Unit No. I cc:
Gerald Garfield, Esquire Kevin McCarthy, Director Day, Berry & Howard Radiation Control Unit Counselors at Law Department of Environmental City Place Protection Hartford, Connecticut 06103-3499 State Office Building Hartford, Connecticut 06106 Edward J. Mroczka Vice President, Nuclear Operations Richard M. Kacich, Supervisor Northeast Utilities Service Company Operating Nuclear Plant Licensing Post Office Box 270 Northeast Utilities Service Company Hartford, Connecticut 06141-0270 Post Office Box 270 Hartford, Connecticut 06141-0270 State of Connecticut Office of Policy and Management ATTN: Under Secretary Energy Division 80 Washington Street Hartford, Connecticut 06106 Regional Administrator, Region I U.S. Nuclear Regulatory Commission 631 Park Avenue King of Prussia, Pennsylvania 19406 Northeast Nuclear Energy Company ATTN: Superintendent Millstone Nuclear Power Station P. O. Box 128 Waterford, Connecticut 06385 Resident Inspector c/o U.S. NRC Millstone Nuclear Power Station P. O. Box 811 Niantic, Connecticut 06357 First Selectman of the Tcan of Waterford Hall of Records 200 Boston Post Road Waterford, Connecticut 06385