ML112900665

LER 80-013/01T-0:on 800309,during Refueling Operations,Rod Withdrawn Block Not Received When Refueling Bridge Traversed Core.Caused by Actuating Arm Out of Adjustment.Components Readjusted & Interlocks Tested Prior to Refueling

ML112900665
Person / Time
Site:	Monticello
Issue date:	03/21/1980
From:	Myrabo A Northern States Power Co
To:	NRC/OI/RGN-III/FO
Shared Package
ML112900666	List: ML112900665 ML19312D522
References
LER-80-013-01T, LER-80-13-1T, NUDOCS 8003240564
Download: ML112900665 (4)

Text

REGULATORY oORMATION DISTRIBUTION SY-*M (RIDS)

ACCESSION NBR:8003240564 DOC,DATE: 80/03/21 NOTARIZED: NO DOCKET #

FACIL:50-263 Monticello Nuclear Generating Plant, Northern States 05000263 AUTHNAME AUTHOR AFFILIATION MYRABO,A,L, Northern States Power Co.

RECIP.NAME RECIPIENT AFFILIATION MYRA8OAL. Region 3, Chicago, Office of the Director

SUBJECT:

LER 80-013/01Tw0:on 800309,during refueling operationsrod withdrawn block not received when refueling bridge traversed core.Caused by actuating arm out of adjustmentComponents readjusted & interlocks tested prior to,refueling.

DISTRIBUTION CODE: A002S COPIES RECEIVED:LTR . 1 ENCL 4 SIZE:._J J ...

TITLE: Incident Reports NOTES: ----------------------------.---------------------- -------------

RECIPIENT C OPIES RECIPIENT COPIES ID CODE/NAME L TTR ENCL ID CODE/NAME LTTR ENCL ACTION: 05 BC 4 4 INTERNAL: EG FIL 1 02 NRC PDR 1 1 09 2 11 MPA 3 3 14 TA/EDO 1 15 NOVAK/KNIEL 1 31 16 EES 1 17 AD FOR ENGR 1 1

18 PLANT SYS BR 1 19 I&C SYS BR 1 1 20 AD PLANT SYS 1 22 REAC SAFT BR 1 1

23 ENGR BR 1 24 KREGER 1 1 25 PWR SYS BR 1 26 AD/SITE ANAL 1 1 27 OPERA LIC BR 1 28 ACDENT ANLYS 1 29 AUX SYS BR 1 AD/ORP-DOR 1 1

AEOD 1 DOUG MAY-TERA 1 HANAUERrS, 1 IRELAND,R,. 3 3 JORDANE,/IE 1 EXTERNAL: 03 LPDR 1 1 04 NSIC 1 1 29 ACRS 16 16 TOTAL NUMBER OF COPIES REQUIRED: LTTR 52 ENCL 52

1" 0 4SIP 0 NORTHERN STATES POWER COMPANY MINNEAPOLIS, MINNESOTA 55401 March 21, 1980 Mr J G Keppler Office of Inspection & Enforcement U S Nuclear Regulatory Commission 799 Roosevelt Road Glen E11yn, IL 60137

Dear Mr Keppler:

MONTICELLO NUCLEAR GENERATING PLANT Docket No. 50-263 License No. DPR-22 Refueling Rod Block Interlock Failure The Licensee Event Report for this occurrence is reproduced on the back of this letter. Enclosed are three copies.

This event is reported 'in accordance with Technical Specification 6.7.B.1.g. in that the condition (limit switch out of adjustment) required refueling operations to be stopped in accordance with Technical Specification 3.10.A.

Yours very truly, N"

L 01 M Ma ager of Nuclear Support Services LOM/JAG/ak cc: &..Director, IE, USNRC (40)

Director, MIPC, USNRC (3)

MPCA Attn: J W Ferman

-over 75 0

NRC FORM 366 U. S. NUCLEAR ItEGULATO;IY COMMISSION (7-77)

LICENSEE EVENT REPORT CONTROL BLOCK: [ (PLEASE PRINT OR TYPE ALL REQUIRED INFORMATION)

IMIN I MINI P1 110101 01 -ll 01ol olol-l ol ol@ 4 1 1111 11 0 LLJ0 LICENSE NUMBER 25 26 LICENSE TYPE 30 57 CAT 58 8 9 LICENSEE CODE 14 15 CON'T REPORT RCEL j@1 05 1 01 0 1NUMBER 01 21 61 3() 01 31 01 91 81 01@1 0 3l1 2 1 8l1 7 8 60 61 DOCKET 68 69 EVENT DATE 74 75 REPORT DATE 80 EVENT DESCRIPTION AND PROBABLE CONSEQUENCES (3 lAt 0605, it was discovered that a rod withdrawal block was not received when the refi1-i ling bridge traversed the core during refueling operations. Technical Specification I 3.10.A requires the refueling interlocks to be operable during core alterations, InterF Ilocks had successfully been tested at 0400 the previous day. Records for that period confirmed that no control rods had been moved while fuel was moved. The event had no jeffect on the public health or safety. One previous occurrence. AO-75-02.

L 00 7 8 9 SYSTEM CAUSE CAUSE COMP. VALVE CODE CODE SUBCODE COMPONENT CODE SUBCODE SUBCODE LF.LDJ@ LW1O@ LA] 12 I1INI SIT IRjU 13 18 19 L1 19 LzI@

20 7 8 9 10 11 SEQUENTIAL OCCURRENCE REPORT REVISION LER/RO EVENT YEAR REPORT NO. CODE TYPE NO.

8[ REPORTSI 1C1131 EUTAO O URRN R RVS 21 22 23 24 26 27 28 29 30 31 32 A"TION FUTURE EFFECT SHUTDOWN ATTACHMENT NPAD-4 PRIME COMP. COMPONENT TAKEN ACTION ON PLANT METHOD HOURS SUBMITTED FORM bUB. SUPPLIER MANUFACTURER IE1 33 34 F 35 z1 36 ZJO 10 l0 l0 l1 l 37 40 N

41 1Nj J 42 43 1j LG 44 108 10 l 47 CAUSE DESCRIPTION AND CORRECTIVE ACTIONS 2 S1 IRefueling operations were immediately stopped. Investigation revealed that the actu- I Iating arm of the limit .switch ( which opens when the bridge is over the core) was out I of adjustment, preventing the switch from operating properly. The components were I readjusted & interlocks tested prior to resuming refueling. Modifications of the j i components are being considered. METHO 7 8 9 80 FACILITY METHO 0 OF STATUS  % POWER OTHER STATUS DISCOV ERY DISCOVERY DESCRIPTION LHH j0 10 10 1(51 1 NA I 4A (2i) Operator observation 7 8 9 10 12 13 44 45 46 80 ACTIVITY CONTENT RELEASED OF RELEASE AMOUNT OF ACTIVITY LOCATION OF RELEASE

[ D[6 1 Lz[J0l NA 1 1 NA l 7 8 9 10 11 44 45 80 PERSONNEL EXPOSURES NUMBER TYPE. DESCRIPTION NA I 7 8 9 11 12 13 80 PERSONNEL INJURIES NUMBER DESCRIPTION EEo1 010 @1 NA I 7 8 9 11 12 80 LOSS OF OR DAMAGE TO FACILITY TYPE DESCRIPTION E

7 8 LJ@I 9 10 NA 80 PUBLICITY NRC USE ONLY ISSUED DESCRIPTION 7 8 ILNJ1 9 10 NA 68 I l 69 IIl l I l I l l l l 80 0

NAME OF PREPARER A. IggbMyrabo PH 612/295-5151 x-266 "'

w 80032,A n5 /

NFAC FO RM 366 U. S. NUCLEAR IREUULAOU'iY COMMISSION rJi F C

CE NS3E E EVE NT R EPO0R T

- CONTROL BLOCK: OPLEASE

' PRINT OR TYPE AL L REQUIRED INFORMATION) 9 MAIN I MINI P il I 0 LICENSEE CODE 14 iS

-0 0,LICENSE NUMBER 01 c0 cII0-1014 10 25 26 1LICENSE 11 1O1O111OLLJ0 TYPE 30 57 CAT 6s CONT REPORT _L 01 510101 01 21 61 3)1 013101918 10 01312,1j.1.1D1j0o(

SOUR CE CLI\_________________

7 8 60 61 DOCKET NUMBER 6F 69 EVENT DATE 74 75 REPORT DATE 80 EVENT DESCRIPTION AND PROBABLE CONSEQUENCES jAt 0605, it was discovered that a rod withdrawal block was not received when the refuel -1 ling bridge traversed the core during refueling oDerations. Technical Specification I 3 .10.A requires the refueling interlocks to be operable during core alterations. Interi jocks had successfully been tested at 0400 the previous day. Records for that period ponfirmed tt no c 1 os h-ad been mo.-ved~ w fulihile was moved. The event had no i ieffect on the public health or safety. One previous occurrence. AO-75-02.

H- I 80 SYSTEM CAUSE CAUSE COMP. VALVE CODE CODE SUBCODE COMPONENT CODE SUBCODE SUBCODE 7

0 8 9 I D 10 LJ 11 Ll@j 12 II1NI SIT IR jU 1 LsJS 13 18 19 Lj@

20 OCCURRENCE REPORT REVISION SEQUENTIAL LE/OfEVENT YEAR REPORT NO. CODE TYPE NO.

0 1 1 31 L--- 1 01 1I LTJI 1---_ E REPORT N 21 8 22 23-- 24 26 27 28 29 30 31 32 A!TION FUTURE EFFECT SHUTDOWN ATTACHMENT NPRD-4 PRIME COMP. COMPONENT TAKEN ACTION ON PLANT METHOD HOURS SUBMITTED FORM SUB. SUPPLIER MANUFACTURER 33 0 F0E 34 I 35 Z] 00 6 36

( 37 l0 0 3Nj 0 40 41 I

42

[NN j 43 IG 1018 1010 44 47 CAUSE DESCRIPTION AND CORRECTIVE ACTIONS 0 Refueling operations were immediately stopped. Investigation revealed that the actu- I lating arm of the limit switch ( which opens when the bridge is over the core) was out I 2of adjustment, preventing the switch from operating properly. The components were j 1 readjusted & interlocks tested prior to resuming refueling. Modifications of the I 4 components are being considered.

7 8 9 80 FACILITY METHOD OF STATUS  % POWER OTHER STATUS DISCOVERY DISCOVERY DESCRIPTION 2 1 5 LJ 10 l10 10 15 NA I L J(3I Operator observation 7 B 9 10 12 13 44 45 46 80 ACTIVITY CONTENT RELEASED OF RELEASE AMOUNT OF ACTIVITY LOCATION OF RELEASE

_0I EI W 1G O LJ@ JgDlNA I @A NA 7 8 9 10 11 44 so PERSONNEL EXPOSURES NUMBER TYPE DESCRIPTION 7 8 9 1010 0 11 12 Z(a 13 NA 80 1

PERSONNEL INJURIES NUMBER DESCRIPTION 7 8 9 010 0 1 11 12 NA 80 1

LOSS OF OR DAMAGE TO FACILITY TYPE DESCRIPTION IDI Z 11 I 7 8 9 10 80 PUBLICITY NRC USE ONLY ISSUED DESCRIPTION 7 N6 1A I 69l ll 7 8 9 10 68 69 80o 0

NAME OF PREPARER A. L. Myrabo PHONE: 612/295-5151 x-266 PHNE J--