05000346/LER-1978-040-03, /03L-1 on 780422:review of Reactor Operator Log Determined That Group 5 Control Rods 100% Zone Ref Light Had Not Been Checked at Required Frequency.Caused by Personnel Error.Process Computer Reminder Program Developed

/03L-1 on 780422:review of Reactor Operator Log Determined That Group 5 Control Rods 100% Zone Ref Light Had Not Been Checked at Required Frequency.Caused by Personnel Error.Process Computer Reminder Program Developed

ML19270F840
Person / Time
Site:	Davis Besse
Issue date:	05/18/1978
From:	Marley J TOLEDO EDISON CO.
To:	NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III)
Shared Package
ML19270F837	List: 05000346/LER-1978-040, Forwards LER 78-040/03L-1 & 78-084/03L-1 05000346/LER-1978-040-03, /03L-1 on 780422:review of Reactor Operator Log Determined That Group 5 Control Rods 100% Zone Ref Light Had Not Been Checked at Required Frequency.Caused by Personnel Error.Process Computer Reminder Program Developed 05000346/LER-1978-084-03, /03L-1 on 780724:floor Drain Check Valve Found Out of Floor Drain in Mechanical Penetration Room 4.Caused by Workmens Error.Valve Replaced & Drains Tagged
References
LER-78-040-03L, LER-78-40-3L, NUDOCS 7903270600
Download: ML19270F840 (2)

LER-1978-040, /03L-1 on 780422:review of Reactor Operator Log Determined That Group 5 Control Rods 100% Zone Ref Light Had Not Been Checked at Required Frequency.Caused by Personnel Error.Process Computer Reminder Program Developed

Event date:
Report date:
3461978040R03 - NRC Website

text

NRC F ORM 366 (7 77)

LICENSEE EVENT REPORT

.h CONTROL BLOCK: l l

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l (PLEASE PRINT OR TYPE ALL REQUIRED INFORMATION) lo l i ] l 0 ] H l D l B l S l 1 l@l 0 ] 0 l - l 0 l 0 l N l P l F l - l 0 ] 3 l@l 4 1l1l1 ll@l l

7 8 9 LICENSEE CODE 14 15 LICENSE NuMBEH 25 26 LICENSE T YPE JU

$ 7 C A T 58 CON'T [7,"c' L l@l 0 l 5 l 0 l - l 0 l 3 l 4 6 hl0l4l2'l2l7l8l@l0l5l1l8l7l8l@

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60 61 DOCKET NUYBEH bd 69 EVENT OATE 74 75 REPORT DATE 80 EVENT DESCRIPTION AND PROBABLE CONSEQUENCES h l o l 2 l l While reviewing the Reactor Operator Log on 4/22/78, it was discovered that the Group [

[olal l 5 Control Rods 100% Zone Reference Light had been last checked on 4/21/78 at 2220

[

o 4

I hours.

Since Group 5 was in asymmetric bypass, TS 3.1.3.3, Action a.2.b requires thatl Group 5 position be verified at least once every 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />. There was no danger to l

o s

The control rods of Group 5 g

l o is l l the health and safety of the public or unit personnel.

l were not in an asymmetric Condition.

(NP-33-78-50) l O

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s i 80 7

8 9 COMP.

VALVE SYSTEU

CAUSE

CAUSE CODE CODE SUBCODE COMPONENT CODE SUSCODE SU8 CODE lojol l Rl B j@ W@ l A l@ lI lN lS lT lR lU l@ l Zl@ W @

7 8

9 to it 12 13 18 13 20 SEQUENTI AL OCCURRENCE REFORT REVISION EVENT YE AR REPOHT NO.

CODE TYPE No.

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_ 21 22 23 24 26 27 28 29 30 31 32 Er7 A T

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33 34 35 J6 3/

40 di 42 43 44 47 CAUSE DESCRIPTION AND CORRECTIVE ACTIONS lThe apparent cause of this occurrence was personnel error. The operator inadvertently [

i o

l failed to perform the required observation of the zone reference light.

An operator [

i i at 2117 hours0.0245 days <br />0.588 hours <br />0.0035 weeks <br />8.055185e-4 months <br /> on April 22, 1978. A l

,,,7glwas dispatched to read the zone reference light l program has been developed for use by the process computer to aid operators in moni-l

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,,g,j ltoring surveillance tests required at frequent intervals when the unit is in an Action l Statement.83 7

8 9 A S

• . PoWE R oTHE R STATUS ISCOV R DISCOVERY DESCRIPTION 6l@l NA l

l A [Ql Operator Log Review l

li 15l W @ l 0l 4

ACTIVITY CONTENT LOCATION OF RELE ASE RELEASED OF RELE ASE AMOUNT OF ACTIVITY W @ lZ l@l NA l

NA l

1 6 80 7

8 9 10 11 44 45 PERSONNEL E XPOSURES CESCRIPTION TYPE @lNA I

NUVHE R 1010 0_j@lZ l

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,ERSONNEl'IN;unS DESCniPTiON@

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~UveEn 1010 Ol@l NA i

R 80 7

8 9 11 12 Loss OF On DAYAGE To F ACILITY l

TYPE DESCniPTION 12 @l NA i o Pumav 7 9 0 3 27 0 6cro sacosecyty [jij l NA I

IIIIIIIIII!l, ISSU E D@DE SCRIPTION i

2 o 68 69 63 3 7

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419-239-5000. Ext. 276 DVR 78-064 Y

PHON E:

NAME OF PREPARER

TOLEDO EDISON COMPANY I

DAVIS-BESSE UNIT ONE NUCLEAR POWER STATION i

SUPPLEMENTAL INFORMATION FOR LER NP-33-78-50 DATE OF EVENT _: April 22, 1978 FACILITY: Davis-Besse Unit 1 IDENTIFICATION OF OCCURRENCE:

Failure to read zone reference light for Group 5 Control Rods when in asymmetric bypass e

The unit was in Mode 1, with Power (MWT) = 1269 Conditions Prior to Occurrence:

and Load (MWE) = 385.

While reviewing the Reactor Operator Log on April 22, Description of Occurrence:

1978, it was discovered that the Group 5 Control Rods 100% Zone Reference Light s

had been last checked on April 21, 1978 at 2220 hours0.0257 days <br />0.617 hours <br />0.00367 weeks <br />8.4471e-4 months <br />. Since Group 5 was in asym-metric bypass, Technical Specification 3.1.3.3, Action a.2.b requires that Group 5 least once be maintained at 0%, 25%, 50%, 75% or 100% withdrawn and verified at every 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />. The position of Group 5 had not been verified by the 100% Zone Reference Light for approximately 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />.

Designation of Apparent Cause of Occurrence: The apparent cause of the occurrence The operator inadvertently failed to perform the required was personnel error.

observation of the zone reference light.

There was no danger to the health and safety of the public Analysis of Occurrence:

The control rods of Group 5 were not in an asymmetric condition.

or unit personnel.

Only the Absolute Position Indication for one control rod was defective requiring operation in asymmetric bypass.

As soon as it was discovered that the zone reference light had

Corrective Action

not been read, an operator was immediately dispatched to read the zone reference 22, 1978.

A program has been developed for use by the light at 2117 hours0.0245 days <br />0.588 hours <br />0.0035 weeks <br />8.055185e-4 months <br /> on April process computer to aid operators in monitoring surveillance tests required at fre-1 quent intervals when the unit is in an Action Statement.

Failure Data: This is not a repetitive occurrence.

LER B78-040