ML20236U707

PN-75-027:on 750522,following Plant Startup Excessive Power Peaking Observed in Lower Region of Core.Licensee Estimates That Stack Release on Initial Isolation Substantially Below Stack Technical Specification Limits.Addl Analysis Done

ML20236U707
Person / Time
Site:	Quad Cities
Issue date:	05/22/1975
From:	Jennifer Davis, Galen Smith, Thornburg H NRC OFFICE OF INSPECTION & ENFORCEMENT (IE)
To:
References
PN-75-027, PN-75-27, NUDOCS 9807300388
Download: ML20236U707 (1)

Text

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PRELIMINARY NOTIFICATION - NOT FOR PUBLIC DISCLOSURE May 22, 1975 l ,, PRELIMINARY NOTIFICATION OF EVENT OR UNUSUAL OCCURRENCE --PN-75-27 l This preliminary notification constitutes EARLY notice of events of POSSIBLE safety or public interest significance. The information presented is as initially received without verification or evaluation I

and is basically all that is known by OIE staf f as of 1:30 p.m. on date of this notification. IT SHOULD BE SPECIFICALLY NOTED THAT THIS NOTIFICATION MAY CONTAIN INFORMATION THAT LATER MAY BE DETERMINED TO l BE INACCURATE OR INCONSISTENT. AN OFFICE OF INSPECTION AND ENFORCEMENT 130TIFICATION OF AN INCIDENT OF OCCURRENCE (BLUE SHEET) SUBSEQUENTLY WILL BE ISSUED IF WARRANTED.

Facility: Commonwealth Edison Company (Quad-Cities Unit 2) l

Subject:

OFF-GAS RELEASE CAUSED BY EXCESSIVE POWER PEAKING The licensee reported that following a plant startup r,riay 22, '975, excessive power peaking was observed in the lower region of the cort. I l Control rod movements were made,in an attempt to reduce peaking, but continued peaking was observed. The 15 minute isolation t'imet actuated  %

_.due to high activity, tripping the air ejector valves. T;.c valves were "

reset and a high spike of off-gas ac,tivity was again observed. t l ( The licensee estimates that the stack release on the initial isolation was  !.

substantially below the stack technical specification limit. '

Three onsite recording GM environmental monitors indicated maximum values of 0.17 mr/hr; 0.08 mr/hr; and, 0.06 mr/hr. These readings confirm the l possibility of an airborne release of radioactive materials.

l The atmosphere was calm and air was in an inversion condition with ground l fog. The licensee is currently making additional analysis.

l l Two Region III inspectors have been dispatched to the facility to evaluate the occurrence.

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Contact:

GHSmith, IE x7261 HDThornburg, IE x7353 JGDavis, IE x7541 Distribution : ..

Chairman Anders Commissioner Mason S. J. Chilk, SECY -

Commissioner Gilinsky"~ Commissioner Rowden G. F. Murphy, JCAE Commissioner Kennedy C. C. Kammerer, CA L. l'. Gossick, EDO D. F. Knuth, IE J. A. Harris, PA g7 B. C. Rusche, NRR H. H. Brown, ISP f

. K. R. Chapman, NMSS H. K, Shapar, ELD pp Transmitted: P Bldg 2 k,.  ; H St 2  ; MD Bldg 1 p

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l PRELIMINARY NOTIFICATION - NOT FOR PUBLIC DISCLOSURE  !

9807300388 750522 ~

PDR I&E i PN-75-027 PDR - I e j

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