ML19354E013

LER 89-008-00:on 891228,equipment Attendant Discovered Refueling Water Storage Tank Vent Line Temp Less than 35 F. Caused by Preservice Deficiency.Storage Tank Vent Path Temp Verified at 36 F.W/900119 Ltr

ML19354E013
Person / Time
Site:	Braidwood
Issue date:	01/16/1990
From:	Melone C, Querio R COMMONWEALTH EDISON CO.
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
BW-90-0078, BW-90-78, LER-89-008-10, LER-89-8-10, NUDOCS 9001250205
Download: ML19354E013 (5)

Text

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• Commonwealth Edison  !

• 4 * ' ^ N) v Br:ld wood Nucirr PJw:t St;ti:n Rout 3 C1. Box 64 I

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Braceville. Illinois 60407 i Telephone 81$/458-2801 j

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January 19,1990 l BW/90-0078 4 i

I U. S. Nuclear Regulatory Commission [

Document Control Desk i Washington, D.C. 20555  !

Dear Sir:

l i The enclosed L!censea Event Report from Braidwood Generating ';

Station is being transmitted to you in accordance with the requirements of l 10CFR50.73(a)(2)(1) which requires a 30-day written report.

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This report is number 89-008-00; Docket No. 50-457.- i

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Very truly yours, l f R.Station E. Querl Manager.

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-l Braldwood Nuclear Station j

REQ /JDW/jfe  !

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Enclosure:

Licensee Event Report No. 89-008-00 l cc: NRC Region !!I Administrator

.fi NRC Resident Inspector  !

INPO Record Center  !

CECO Distribution List i i

'9001250205'900116 M I

PDR ADOCK 05000457 j S PDC

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LICENSEE EVENT REPORT (LER) , g iccility home (1) Docket Number (2) Pane (1) ,

traidwood 2 01 El 01 01 01 41 El 7 1lefl0l4 Title (4) Refueling Water Storage Tank Vent Line Temperatee Less Than 35 Degrees F Due to Preservice Deficiency-d vent Date (El LER Number (6) Recort Date (7) Other Facilities Involved (B)

Moeth Pay Year Year /// Sequential /j/j/ Revision Month Day Year Facility "s Docket % d er(s)

//j/j f

Jumber f

/// Number None 01 51 01 01 01 l l

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11'2 21 e el 9 Bl 9 010l8 01 0 0l1 11 6 91 0 01 El 01 01 01 l l THIS REPORT IS SUBMITTED PURSUANT TO THE REQUIREMENTS OF 10CFR OPER M (theek one or more of the followino) (11) 1 E0.402(b) _ 20.40$(c) __ 50.73(a)(2)(iv) ._ 73.7)(b)

POWER _ 20.405(a)(1)(1) _ 50.36(c)(1) _ 50.73(a)(2)(v) _ 73.71(c)

LEVEL 20.405(a)(1)(ii) __ 50.36(c)(2) __._ 50.73(a)(2)(vii) .__. Other (Specify (101 0..!. 9 ! 9- _ 20.405(a)(1)(lii) _1_ 50.72(a)(2)(i) ._ 50.73(a)(2)(viii)(A) in Abstract

// / /,// /,/ /,// /,/ / / //,/,/,/,// / /,/,/ __ 20.405(a)(1)(iv) _ 50.73(a)(2)(ii) _ 50.73(a)(2)(viii)(B) below and in

///j///}/Q///j/////}/}/j/j////// / 20.405(alli)(v) ._._ 50.73(a)(2)(iii) _ 50.73(a)(2)(x) Text)

LICENSEE CONTACT FOR THIS LER (12)

Name TELEPHONE NutBER ,

AREA CODE C. Melone. Technical Staf f Ennineer Ext. 2440 8l115 41 El 81 l 21 81 01 COMPLETE ONE LINE FOR EAEH COMPON N FAILURE DESCRIBED IN THis REPORT (13)

CAUSE SYSTEM COMPONENT MANUFAC- REPORTABLE CAUSE SYSTEM COMPONENT MANUFAC- REPORTABLE TURER TO NPRDS TURER TO NPRDS I I I I I I I I I I I I I l-1 I I I I I I I l l l l l 1 -

SUPPLEMENTAL REPORT EXPECTED (14) Expected Month l Day l Year Submission

_hti_i U_.yfidMRlt ti.E X PE CT E D SUI)MUi10!LD AT E ) X l NO l ll ll ABSTRACT (Limit to 1400 spaces, i.e, approximately fif teen single-space typewritten lines) (16)

Outside air temperatures had beer fit' i 0 degrees F for several days with nightly lows reaching -18 degrees F.

, During the Midnight Shif t on Deced e 7,1989 an Equipment Attendant = (EA) and an EA trainee performing Auxiliary j Building Rounds recordeti the Unit s Rs$ueling Water Storage Tank (RWST) vent line temperature as 34 degrees F.

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- This temperature was required to be >/-35 degrees F. The EA trainee telephoned this information to the Unit 2 Nuclear Station Operator (NS0) who entered it in the NSO rounds. The HSO did not identify the below minimum reading. The rounds were reviewed by several supervisors who did not identify the below minimum reading. At 1430 during a review of the rounds, the below minimum reading was discovered. An EA was imediately dispatched to check the temperature. It was 36 degrees F. The cause of this event was a preservice deficiency. The capacity of the electrical heat tracing was not adequate. The failure to identify the below limit reading was due to ptrsonnel error, absence of alann, and absence of an administrative temperature limit. The RWST heater was placed in continual operation. The EA rounds will be revised. Methods to increase vent line heating capability and provide for a low temperature alarm will be evaluated. Training will be conducted. A program will be developed to flag rounds with an out of tolerance reading. No previous occurrences.

2974m(011990)/2

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-b Liersarr tvtNT kEPORT (LEkl TEXT CONTItRRTION Form key 2.0

' FACILITY H M (1) DOCKET NUSER (2)-- Lta etmare (6) - Paon (M I Year fj/j/ Sequential /j/j/

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f Revision ]

/// M r /// Number l

_traidwood 2 oIsIeIoIo 1 41 51 7 a19 - D1ol8 - 01 0 el 2 0F 01 4 TEXT- Energy Industry Identification System (Ells) codes are identified in the text as (XX)

,.A. IPLANT CONDITIONS PRIOR TO EVENT:

=i Unit: Braidwood 2; Event Date: December 22, 1989; Event Time: 1430 Mode: 1 - Power Operation; Rx Power: 99 2 ; i L ,

-RCS (AB) Temperature / Pressure: NOT/NOP i i

B. DESCR!pTION OF EVENT:

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There were no systems or components inoperable at the beginning of the event which contributed to the severity of '

the event. = Outside air temperatures at the station had been below 0 degrees F for several days prior to the event with nightly lows reaching -18 degrees F.

During the Nidnight Shif t on December 22, 1989 an Equipment Attendant (EA)(Non-Licensed Operator) and an EA ,

trainee were performing Auxiliary Butiding Rounds for Unit 2. One of the locally indicating values recorded in .;

the rounds was the Refueling Water Storage Tank (RWST) (9Q/BR) vent line temperature. This temperature was-

- required to be verified >/s35 degrees F on a daily frequency when outside. air temperature was less than 35 degrees F. The EA trainee recorded the indicated value of 34 degrees F. ,

The RWST vent path temperature is required to be transferred to the Nuclear Station Operator (NS0) (Licensed Reactor Operator) rounds sheet. The EA trainee telephoned this-information to the Unit 1 N$0 who recorded it in the Unit 2 NSO rounds. The NSO failed to recognize that the entered value was below the 35 degree F minimum.

THE NSO rounds were reviewed by'the Station Control Room Engineer ($CRE) (Licensed Senior Reactor' Opera' tor) (SRO) I who did not identify the below minimum reading. The EA rounds were reviewed by the Unit 2 NSO and the Shift-Foreman ($RO Licensed $vparvisor) who also did not identify the below minimum reading.

l- - At 1430 during the review of the Unit 2 NSO rounds, the day shif t SCRE discovered that the RWST vent path temperature was recorded as being one degree below the minimum value. An EA was issnediately dispatched to check the Unit 2 RWST vent path Temperature. The temperature was 36 degrees F. ,

This event is being reported pursuant to 10CFR50.73(a)(2)(1) - any operation or condition, prohibited by the plant's Technical $pecifications.

Bassd on the initial information associated with this event, a "Braidwood Station Error Evaluation Presentation" was held to review this event.with the personnel directly involved and their supervisor. 'The corrective-actions I cadrsssing both root and contributing causes are detailed below, f I

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l2974m(011990)/3

. LICEptrr EVDff REP 0kT (LERl TEXT EONTitamT1DN Fare kev'2.0

' FACILITY NAE (1) DOCKET NUSER (2) LER liteEt (6) Pane (3)

Sequential

. Year //{

ff /{f/ Revision f

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///  % =her ///

I eralse 2- O l's 1 0 1 0 1 0 1 41 El 7 aI9 - 010l8 - 0 l= 0 01 3 0F 01 4 {

TEXT Energy industry identification System (EIIS) codes are identified in the text as [XX) l:

C; CAU$E OF EVENT  !

'The' root cause of this event was a preservice deficiency. The capacity of.the electrical heat tracing of the

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RWST vent line was not adequate to maintale the temperature above 35 degrees F with outside air temperature at IB' degrees F below zero.

- The cause of. the f ailure to identify the below' limit read was personnel error. .Both the EA and NS0' rounds

identified the reading as a Technical Specification reading. Both rounds identified that the minimum eccsptable value was 35 degrees F.

y C:ntributing causes to the failure to identify the below limit reading were:

1. There were no alarms associated with the RWST vent line temperature to key personnel into recognizing that a parameter was approaching a limit.

2. The rounds did not have an Administrative" Limit to alert personnel that a parameter is trending towards an unacceptable limit.  ;

D. SAFETY ANALYSIS: ,

This event had no effect on the safety of the plant or the public. The RWST_was' functional and available.

Boration capability was also available f rom the Boric Acid Storage Tank (GA).-

Under the worst case condition of extended low temperature RWST Vent Line conditions causing an icing on the j v:nt line, there would still be no effect. Based on data contained in section 6 of the Updated Final Safety j . Analysis Report, adequate excess net positive suctisn head is available for operation of ECCS equipment even l trith a partial vacuum in the RWST. Prompt Operator recogni.tlon and action to remove from operation any component experiencing cavitation symptoms would provide for adequate ECCS operation until the switchover to r: circulation phase where the RWST would no longer be providing suction to ECCS components, g E. ' CORRECTIVE ACTIONS:

The RWST Vent Path temperature was verified at 36 degrees F upon discovery that it had been recorded at 34

( dIgrees F on the previous shift.

The Electrical Heat tracing was checked. It was found to be operating.

'. The RWST heater was placed in a " continual operation mode to raise RWST temperature which would provide .

L. additional heat to the vent line.

l RWST Vent Path Temperature was monitored.twice per eight hour shif t until December 26, 1989 when outside air f

' temperature was above 35 degrees F and RWST vent path temperature had been indicating above.48 degrees F for several days. '

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,2974miO11990)/4

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. . LICENSEE EVENT REPORT (LER) TEXT CONTINUATION Form key 2.0

'IACILITY~NAME (1) DOCKET NUMBER (2) LER MUMBER (6) Paoe (3)

Year. /// Sequential /// Revision fff fff

/// Numbgr /// Mer

,praidwood 2 0 1 5 1 0 1 0 1 0 1 41 El 7 819 - 010lB - 0l 0 01 4 0F Dj 4 TEXT Energy Industry Identification System (E!!$) codes are identified in the text as (XX)

Bas:d on the initial information associated with this event the personnel directly involved with this event I participated in a "Braidwood Station Error Evaluation Presentation" to identify root and contributing causes of this event. Based on the conclusions of this presentation the following corrective actions will be taken:

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1. The EA rounds sheets will be revised to include an administrative limit for RWST Vent Path temperature.

This limit will provide advance notification so corrective actions can be taken prior to reaching the Technical- Specification Limit. The rounds will also be revised to add a note on each page where readings are taken for Technical Specification requirements instructing the EA to immediately notify the Shift Supervisor of an out of tolerance Technical Specification reading. These actions will be tracked to completion by action item 457-200-89-09201.

2. An evaluation will be conducted to identify methods to increase the capability to heat the RW$T Vent '

Line and provide for a low temperature alare. This will be tracked to completion by action item 457-200-89-09202,

3. LThis event will be covered in a training tailgate session with appropriate Operating shif t personnel.

This will be tracked to completion by action item 457-200-89-09203. ,

4 A program will be developed to provide a aflagging" mechanism for rounds where an out of tolerance ,

Technical Specification reading has been recorded. This action will be tracked to completion by action

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item 457-200-89-09204.

l F. PREVIOUS OCCURRENCES There have been no previous occurrences.

G. COMPONENT FAILURE DATA:

This event was not the result of component failure, nor did any components fall as a result of this event.

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