ML20024B835

LER 83-028/03L-0:on 830603 & 17,fuel Handling Area Radiation Monitors RE8446 & 7 Found Deenergized.Caused by Blown Radiation Monitoring Cabinet Fuse.Fuse replaced.W/830701 Ltr

ML20024B835
Person / Time
Site:	Davis Besse
Issue date:	07/01/1983
From:	Murray T, Swartz J TOLEDO EDISON CO.
To:	James Keppler NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III)
References
K83-957, LER-83-028-03L, LER-83-28-3L, NUDOCS 8307110482
Download: ML20024B835 (3)

Text

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NRC FhM 366 ~

U.S. NUCLEAR REGULATORY COMMISSION

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• i LICENSEE EVENT REPORT (PLEASE PRINT OR TYPE ALL REQUIRED INFORMATION)

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7 8 9 LICENSEE CODE 14 15 LICENSE NwMBER /6 LICENSE TYPE JO CON'T IIIII S$RC lL lgl0 l 5 l0 l0 l0 l3 l4 l6 @l069 l610 l3 l8 l3 l@l 0 75l 7 lREPORT 74 0 l 1DATE l 8 l 380l@

7 8 60 61 DOCK ET NUMB ER 68 EVENT DATE EVENT DESCRIPTION AND PROBABLE CONSEQUENCES h IOl2l l(NP-33-83-37) On 6/3/83 at 0825 hours0.00955 days <br />0.229 hours <br />0.00136 weeks <br />3.139125e-4 months <br />, the fuel handling area radiation monitor RE84461 ib TTl Iwas found de-energized. Since RE8446 initiates Emergency Ventilation System (EVS) l Io i4 l l Train 1, the station was placed in action statement (a) of Tech Spec 3.9.12 for one i l I O l s i li noperable EVS _ train. On 6/17/83 at 0050 hours5.787037e-4 days <br />0.0139 hours <br />8.267196e-5 weeks <br />1.9025e-5 months <br />, RE8447 was found d'e-energized, again l ~ ~

10 Is l lplacing the unit in Tech Spec 3.9.12. There was no danger to the health and safety ofl l 0 l 7 l I the public or station personnel. During both occurrences, the redundant monitor and l l018l l associated EVS train were operable. I E CODE S SC E COMPONENT CODE SUSCODE S E lTlT) lB l A l@ ]@ l Fl@ lIl Nl S l T l R l U lh W@ y @

12 13 18 19 20 7 8 9 to '11 SEQUENTIAL OCCURRENCE REPORT REVISION

,_ EVENT YEAR REPORT NO. CODE TYPE N O.

Nu'E 18 13I O "LER/Ro l-l 10 l2 l8 l 24 26 y

27 lg l3 l 28 29 lt l 30 l_l 31 l0 l 32

_.21 22 23 N A ON PL NT ME HOURS S8 i FOR b 8. SUPPLI MANUF CTURER lA 33 lgl34Zl@ d@ b@

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41 l42Y l@ l N lg 43 l V j 1 l 1-l 5 lg 44 47 CAUSE DESCRIPTION AND CORRECTIVE ACTIONS IIl0llThe cause of both occurrences was a blown fuse in the radiation monitoring cabinet. l

[1 lij lThere was no evidence of excessive heating or current upon inspection of the fuse, fusa

' lii2i l older,h and associated wiring. For both occurrences, the blown fase was replaced undert l ,,i3i lMWO 83-1027. RE8446 and EVS Train 1 were declared operable at 2200 hours0.0255 days <br />0.611 hours <br />0.00364 weeks <br />8.371e-4 months <br /> on 6/4/83, l i,i4i land RE8447 and EVS Train 2 vere declared operable at 1015 hours0.0117 days <br />0.282 hours <br />0.00168 weeks <br />3.862075e-4 months <br /> on 6/17/83. l 7 8 9 80 SA  % POWER OTHER STATUS 01 O RY DISCOVERY DESCRIPTION lYIII W@ l019 l1 lhl NA l W @l Durine performance of ST 5099.05 l ACTIVITY CO TENT AMOUNT OF ACTIVITY LOCATION OF RELEASE 1 6 y RELEASE @D NA OF RELEASE @ll 44 l NA 45 80 l

7 8 9 10 11 PERSONNEL EXPOSURES NUM8ER TYPE NA R 10 IO l0 l@l Z lhl DESCRIPTION l PERSONNELINJU IES NUV8ER DESCRIPTION @ gL l 11 la8 l910 l0 l0 l@l 12NA 11 80 7

TYPE DESCR PT ON y lZ l@l NA l iSSUso PuBLETv OESCRIPTION U c 8307110482 830701 PDR ADOCK 05000346 NRC USE ONLY t

7 2 o 8 9 Ohl NA 10 S PDR l 68 69 IlIIIIlIIIIIli 80 5

DVR 83-070 & Ogygoppggp,ggg Mn hanz pgoyg; 419-259-5000, Ext. 225 g.

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TOLEDO EDISON COMPANY DAVIS-BESSE NUCLEAR POWER STATION UNIT ONE -

SUPPLEMENTAL INFORMATION FOR LER NP-33-83-37 DATE OF EVENT: June 3 and 17, 1983 FACILITY: Davis-Besse Unit 1 IDENTIFICATION OF OCCURRENCE: Radiation Monitors RE8446 and RE8447 found de-energized ,

Conditions Prior to Occurrence: On June 3, 1983 the unit was in Mode 1, with Power (MWt) = 2529 and Load (Gross MWe) = 835. On June 17, 1983 the unit was in Mode 1 with Power (MWt) = 2505 and Load (Gross MWe) = 827.

Description of Occurrence: At 0825 hours0.00955 days <br />0.229 hours <br />0.00136 weeks <br />3.139125e-4 months <br /> on June 3, 1983, while performing ST 5099.05, Radiation Monitoring Shif t Check, the Control Room Operator - =

found radiation monitoring cabinet C5762B de-energized. As a result, RE8446, a Fuel Handling Area exhaust radiation monitor was de-energized.

Technical Specification 3.9.12 requires that "two independent Emergency Ventilation Systems (EVS) servicing the storage pool area shall be operable".

Since RE8446 actuates EVS Train 1 in the event of a high radiation condition  : -- -_

in the Spent Fuel Pool / Fuel Handling Area, EVS Train 1 was declared inoperable, placing the unit in action statement (a) of Technical Specifica-tion 3.9.12.

A similar event occurred on June 17, 1983 at 0050 hours5.787037e-4 days <br />0.0139 hours <br />8.267196e-5 weeks <br />1.9025e-5 months <br /> in radiation monitoring cabinet C5755B and resulted in the de-energization of RE8447.

Again, the unit was placed in the action statement of Technical Specifica-tion 3.9.12 for an inoperable EVS train (Train 2).

Designation of Apparent Cause of Occurrence: The cause of both occurrences was due to a blown fuse in the associated radiation monitoring cabinet.

There was no evidence of excessive current or heating upon inspection of the fuse, fuse holder, and associated viring.

Analysis of Occurrence: There was no dsnger to the health and safety of the public or station personnel. During each occurrence, the redundant monitor and its associated EVS train were operable.

Corrective Action: By 0900 hours0.0104 days <br />0.25 hours <br />0.00149 weeks <br />3.4245e-4 months <br /> on June 3, 1983, the blown fuse was replaced under Maintenance Work Order 83-1027, and the radiation monitor-ing cabinec was re-energized at 1000 hours0.0116 days <br />0.278 hours <br />0.00165 weeks <br />3.805e-4 months <br /> on June 4, 1983. ST 5032.01,

• 2 Radiation Monitoring System Functional Check, was successfully completed on June 7, 1983 at 2200 hours0.0255 days <br />0.611 hours <br />0.00364 weeks <br />8.371e-4 months <br />, and RE8446 and EVS Train 1.were declared operable. This removed the unit from the action statement.

Again under Maintenance Work Order 83-1027, the blown fuse was replaced, and the radiation monitoring cabinet re-energized. ST 5032.01 was per-formed, and RE8447 and EVS Train 2 declared operable at 1015 hours0.0117 days <br />0.282 hours <br />0.00168 weeks <br />3.862075e-4 months <br /> on June 17, 1983.

Failure Data: There have been no similar failures of these radiation monitors since 1978.

LER # 83-028 e

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.. a48/M .

TOLEDO

%s EDISON July 1, 1983 Log No. K83-957 File: RR2 (NP-33-83-37)

Docket No. 50-346 License No. NPF-3 Mr. James G. Keppler Regional Administrator, Region III Office of Inspection and Enforcement U. S. Nuclear Regulatory Commission 799 Roosevelt Road Glen Ellyn, Illinois 60137

Dear Mr. Keppler:

LER No.83-028 Davis-Besse Nuclear Power Station Unit 1 Date of Occurrence: June 3, 1983 Enclosed are three copies of Licensee Event Report 83-028 which are being submitted in accordance with Technical Specification 6.9 to provide 30 day written notification of the subject occurrence.

Yours truly, MD%

Terry D. Murray Station Superintendent Davis-Besse Nuclear Power Station

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TDM/ljk Enclosures cc: Mr. Richard DeYoung, Director l Office of Inspection and Enforcement i Encl: 30 copies l

l Mr. Norman Haller, Director

( Office of Management and Program Analysis l '. Enc 1: 3 copies l\ k, $

Mr. Tom Peebles NRC Resident Inspector Encl: 1 copy gg'g e

THE TOLEDO EDISON COMPANY EDISON PLAZA 300 MACISON AVENUE TOLEDO. OHIO 43652

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