ML19256C934
| ML19256C934 | |
| Person / Time | |
|---|---|
| Site: | Browns Ferry  |
| Issue date: | 07/09/1979 |
| From: | Flack E, Higginbotham L NRC OFFICE OF INSPECTION & ENFORCEMENT (IE) |
| To: | |
| References | |
| PNO-79-225, NUDOCS 7910150761 | |
| Download: ML19256C934 (1) | |
Text
PRELIMINARY NOTIFICATION July 9, 1979 PRELIMINARY NOTIFICATION OF EVENT OR UNUSUAL OCCURRENCE PNO-79-225 This preliminary notification constitutes EARLY notice of an event j
of POSSIBLE safety or public interest significance.
The information presented is as initially received without verification or evaluation and is basically all that is known by IE staff as of this date.
FACI LI_T_Y: Tennessee Valley Authority Browns Ferry, Unit No. 1 License No. DPR-33 Athens, Alabama
SUBJECT:
INADVERTENT RELEASE OF LOW LEVEL ACTIVITY On July 6, during routine surveillance testing, a Residual Heat Removal (RHR) system service water alarm occurred indicating a radioactive release from Unit 1.
The RHR heat exchanger was promptly isolated.
Unit 1 was operating at full power.
A service water sample from the isolated heat exchanger analyzed after the isolation indicated 13.6 percent of MPC.
Upon subsequent testing, a second high activity alarm occurred.
The heat exchanger was again isolated and a service water sample taken which indicated 8 percent of MPC.
A hydrostatic test of the heat exchanger showed no leaks.
Subsequent evaluation indicated that the activity was from a primary to service wateraleak which had occurred about 2 years ago.
The former leak apparently deposited low level activity in the service water side of the heat exchanger which is periodically released due to changes in heat exchanger operation.
Media interest is not expected.
Neither the licensee nor the NRC plan to issue a news release.
The State of Alabama has been informed.
Region II (Atlantej received notification of this occurrence by telephone from the NRC resident inspector at 7:55 p.m. on July 6.
This information is current as of 10:30 a.m. on July 9.
Contact:
EDFlack, IE x28188 LBHigginbotham, IE x28485 Distribution:
Transmitted H St Chairman Hendrie Commissioner Bradford S. J. Chilk, SECY Commissioner Kennedy Commissioner Ahearne C. C. Kammerer, CA Commissioner Gilinsky ACRS (For Distribution)
Transmitted:
MNBB P. Bldg 9 :/c V. Stel.lo., IE L. V. Gossick, ED0 H. R. Denton, NRR Region JL H. L. Ornstein, E00 R. C. DeYoung, NRR J. J. Fouchard, PA R. J. Mattson, NRR N. M. Haller, MPA D. Vassallo, NRR (MAIL)
R. G. Ryan, OSP D. Eisenhut, NRR J. J. Cummings, 0IA H. K. Shapar, ELD SS Bldg R. Minogue, SD W. J. Dircks, NMSS gG h S. Levine, RES PRELIMINARY NOTIFICATION 4 91015 0 7M f