ML20148A723

/03L-0 on 781111:during S.P.6.4.1.2. (Withdrawn Control Rod Operability), Control Rod 30-31 Was Found Uncoupled from Its Control Rod Drive. Cause Cannot Be Determined Until Control Rod Drive Is Removed & Examined

ML20148A723
Person / Time
Site:	Cooper
Issue date:	12/07/1978
From:	Ballinger P NEBRASKA PUBLIC POWER DISTRICT
To:
Shared Package
ML20148A721	List: ML20148A716 ML20148A723
References
LER-78-034-03L, LER-78-34-3L, NUDOCS 7812290201
Download: ML20148A723 (1)

Text

U. S. NUCLE AR REGULATORY COMM ON NRef 0W 366

$77 P -

. LICENSEE EVENT REPORT A

U CONTROL BLOCK: l l l l l l l@ (PLEASE PRINT OR TYPE ALL REQUIRED INFORMATION) 1 6 l0 l1l8 9lN lELICENSEE 7

lC lPCODE lRl1 l@l0 l0 l -l 0 l 0LICENSE 14 lb l 0 lNUMBEH O l -l 0 l O l 0 l@l26 4 ILICENSE 2S i l 1 l TYPEil 130l@l67 CAT l 58 I@

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68 69 EVENT OATE REPORT DATE

/ 8 60 61 DOCK ET NUMBER EVENT DESCHIP1lON AND PROBABLE CONSEQUENCES h 10121lDuring performance of S.P. 6.4.1.2 (Withdrawn Control Rori Opornh414 9 y1 cnnern1 rnd 3n_ l LO l 31 l31 was found uncoupled from its control rod drive. This condition was in violation of 1 l l

lo I4 l lCNS Tech. Spec. 3.3.B.l. The control rod was recoupled to its control rod drive and veTj- )

[Olsl g led per CNS surveillance procedure 6.4.1.2. Reactor was in run at approximately 72% l lo is l l power. Redundant systems were operable. Control rod shall be monitored for recurrence l l 0 l 7 l [of event. The CRD will be removed and examined to determine cause of this occurrence. l loisj lA similar event was reported on October 28, 1977 under report No. 50-298-77-52. I 80 7 8 9 SYSTEM CAUSE CAUSE COMP. VALVF CCDE CODE SUBCODE COMPONENT CODE SuBCODE SUBCODE 10191 7 8 IR lB l@ l xl@ l z l@ I x I x l x lx l x lx l@ LzJ@ l zl @

9 10 11 12 13 18 19 20 SEQUENTI AL OCCURRENCE HEPOHT REVISION LE R EVENT YE AR REPoHT NO. CODE TYPE NO.

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CAUSE DESCRIPTION AND CORh- CTIVE ACTIONS h l i l o l l Cont rol rod was recoupled to its control rod drive and verified ner CNS nrocedure l lilij 16.4.1.2. The control rod drive will be removed and examined to determine thn cnnco nf I l

l,l7j lthe uncoupling. An updated LER shall be submitted at that time. Date for removal and l l 1iI3l lcxamination of CRD 30-31 is tentatively scheduled for April 1979. l l

[I l4l ! 80 7 8 9 l 81 J  % POWE R OTHER STATUS IS O R DISCOVEHY DESCHIPTION lt l 5 l lE l@ l 0 l 7 l 2 l@l NA I l B l@hontrol rod operability check per 6.4.1.j A TiVl f Y CO TENT HELE ASE D OF HE LE ASF AMOUNT OF ACTIVITY LOCATION OF RELE ASE NA l NA I Ii Ic Hl 9lz I@ l z l@l

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1 PE HSONNEL E MPOSURES NUMH(H TYPE DE SCHIPTION -

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