ML19256C625
| ML19256C625 | |
| Person / Time | |
|---|---|
| Site: | Big Rock Point File:Consumers Energy icon.png |
| Issue date: | 04/23/1979 |
| From: | Bryan S, Klinger G, Nolan F NRC OFFICE OF INSPECTION & ENFORCEMENT (IE) |
| To: | |
| References | |
| PNO-79-090, PNO-79-90, NUDOCS 7910100630 | |
| Download: ML19256C625 (2) | |
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PRELIMINARY NOTIFICATION a..t
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April 23, 1979 PRELIMINARY NOTIFICATION OF EVENT OR UNUSUAL OCCURRENCE -- PN0-79-90 d
i JJL s preliminary notification constitutes EARLY notice of event of POSSIBLE safety or public interest significance.
The information presented is as initially received without verification or evaluation and is basically all that is k,own by IE staff on this date.
Facility:
Consumers Power Company, Big Rock Point (DN 50-155), Charlevoix, MI
Subject:
REACTOR COOLANT PRESSURE B0UNDARY LEAK The licensee reported to RIII that while hydrotesting the pressure e sel at 900 psig in preparation for startup followin age, a small primary system leak (8-10 cc/ min.)g an extended refueling aut-was observed.
The leak was located on Control Rod Drive. Thimble, F-2, at the weld joining the thimble to the reactor vessel (See Figure 1).
Presence of deposits around the leaking thimble indicates thu leak has been present for sometime.
No estimate of delay in startup has yet been made, however, the repair may require defueling of the reactor.
RIII plans to review this matter onsite.
The State of Michigan has been notified.
The licensee and NRC do not intend to issue a press release at this time.
This information was reported to RIII by the plant Technical Engineer at 2:30 p.m., on April 20, 1979.
The news media is aware of the leak and has made inquiries to both the licensee and RIII.
Contact:
GKlingler, IE x28019 FNolan, IE x28019 SEBryan, IE x28019 Sistribution:
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% airman Hendrie Commissioner Bradford S. J. Chilk, SECY Commissioner Kennedy Commissioner Ahearne C. C. Kammerer, CA Commissioner Gilinsky (For Distribution)
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P. Bldg // //L' J. G. Davis, IE H. L. Ornstein, EDO R. C. DeYoung, NRR
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L. V. Gossick, EDO H. R. Denton, NRR Region -hc J. J. Fouchard, PA R. J. Mattson, NRR H. M. Haller, MPA V. Stello, NRR (MAIL)
R. G. Ryan, OSP R. S. Boyd, NRR J. J. Cummings, 01A
~H. K. Shapar, ELD SS Bldg / 2aC9 R. Minogue, SD W. J. Dircks, NMSS S. Levine, RES I
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