IR 05000456/1990020

Insp Rept 50-456/90-20 on 901004-06.No Violations or Deviations Noted.Major Areas Inspected:Review of Operator Performance & Supervisory Overview During Incident Determining Adequacy of Operating Procedures

ML20058B956
Person / Time
Site:	Braidwood
Issue date:	10/22/1990
From:	Shafer W NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III)
To:
Shared Package
ML20058B955	List: IR 05000456/1990020 ML20058B953 ML20058F985
References
50-456-90-20, NUDOCS 9010310113
Download: ML20058B956 (23)

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U.S. NUCLEAR REGULATORY COMMISSION

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REGION III

Report No. 50-456/90-020(DRP)

-l Docket No. 50-456 Licenses No. NPF-72

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Licensee: Commonwealth Edison Company

Post Office Box 767 Chicago, IL 60690 Facility Name:

Braidwood Station, Unit 1 Inspection At: Braidwood Site, Braidwood, Illinois Inspection Conducted:

October 4-6, 1990 l

Inspectors:

W. D. Shafer, Team Leader, DRP, RIII S. G. DuPont, Senior Resident Inspector, Dresden W. J. Kropp, Senior Resident Inspector, Byron J. A. Hopkins, Resident Inspector. Braidwood S. P. Sands, Licensing Project Manager, NRR E. A. Trager, Jr., AE00 S. Diab, Risk Applications, NRR J.

.Harbqur,IdahoNationalEngineering_Laborntory Approved By:

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//Y2;L /Yd Reactor Projects Branch 1 Date

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Inspection' Summary l

Inspection on October 4-6, 1990 (Report No. 50-456/900(DRP))

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Areas Inspected:

Special Augmented Inspection. Team (AIT) inspection conducted in response to the Unit 1, loss of RCS. inventory event of October 4, 1990.

The review included validation of the sequence of events, evaluation of the licensee's response to the event, determination of the root cause for the

opening of the RHR Hot Leg Isolation Valve with the RHR Suction.Line Vent Valve open, validation of the flow path and volume of water discharged from the RCS to the Auxiliary Building, review of operator performance and-supervisory overview during the incident, determining the adequacy of operating

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procedures, administrative controls, and communications for coordinating surveillance testing activities related to the event, and a comparison of the loss of coolant event of March 18, 1990 (IR No. 50457/90012DRP) for similarities and to determine if the corrective actions taken for.the previous event should have prevented the October 4, 1990 event.

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• t Results: No violations or deviations were identified; however, several

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-concerns relating to the performance of personnel involved in the event and the lack of shift. crew involvement was identified (Section VII).

The licensee committed to conduct an independent investigation of the event and will make the results of that investigation available to the NRC.

In addition, the licensee made several commitments to interim corrective actions I

as identified in the exit interview (Section IX).

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TABLE OF C0tTENTS,

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INTRODUCTION

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A.

'SYl10PSIS OF EVENT S.-

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B.

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All CHARTER

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D.

. PERSONS C0!lTACTED

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DESCRIPTION A,

ilARRATIVE DESCRIPTION..

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SEQUENCE -.0F EVEllTS-

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AliALYSIS

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INVESTIGATIVE EFFORTS

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OPERATIONS-ORGANIZATION-INVOLVEMENT 19L M

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TECHNICALtSTAFF lNVOLVEMENT..

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WORK ~ PLANNING ^1NVOLVEMENT-

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INTERSYSTEM LOCA POTENTIAli

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IV.

LICENSEE INVESTIGATION

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AIT EVALUATION 19-t

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CONCLUSIONS'

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COMPARISON.OF THE MARCH 18, 1990LLOSS OF COOLANT EVENT-TO THE1

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OCTOBER 4',

1990 EVENT-

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THE MARCH 18. 1990 EVENT

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THE OCTOBER 4,1990. EVENT.

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CONCLUSIONS

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VI.

SAFETY SIGNIFICANCE OF THE EVENT'

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AIT CONCERNS AND RECOMMENDATIONS ^

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CONCERNS L 21-t

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RECOMMENDATIONS'

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AIT CHARTER COMPLETION;

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DETAILS

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1.

Introduction

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l A.

_ Synopsis of Event

On October 3-4, 1990, Braidwood Unit I was in cold shutdown with l

surveillance testing in process on the Residual Heat Removal (RHR)

y system in anticipation for returning Unit 1 to service following a forced maintenance outage that occurred after a reactor trip on September 29, 1990. The station's-technical staff was conducting two surveillances concurrently, BwVS 4.6.2.2-1, " Reactor Coolant System Pressure Isolation Valve Leakage" and BwVS 0.5-2.RH.2-1,

" Residual Heat Removal Valve Stroke Test".

The purpose of

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surveillance, BwVS 4.6.2.2-1, was to identify and measure any leakage of reactor coolant system (RCS) past the RHR 12" hot leg suction isolation valves RH8702A and B (Train B),

The purpose of surveillance BwVS 0.5-2.RH.2-l', was'to time the stroke of valves RH8702A and RH87028 to the open position.

Since surveillance BwVS 4.6.2.2-1, required. stroking of the RHR: hot _ leg suction isolation valves to the open position, the station's technical staff decided to time the open stroke of the_ valves to also meet

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the requirements of surveillance BwVS 0.5-2.RH.2-1.

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The RHR system configuration at the time was valve RH8702A open (downstream of RH8702B) and vent valve (downstream of RH8702A)

RH028B open to measure any leakage of RCS past RH8702B which was closed. After completion of the leakage' measurement', a technical

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staff engineer in the main control room directed the _ equipment attendant to close vent valve RH0288.. Shortly after those instructions were communicated to the-inplant personnel, another technical staff engineer'in the main. control room-directed the-Auxiliary Nuclear Station Operator, to open isolation valve RH87028 to measure the stroke time per surveillance BwVS-0.5-2 RH.2-1.

Since the equipment attendent was still closing the vent valve, RCS water at 360'psig and 180'F exited the vent valve, ruptured a tygon tube line and sprayed two engineers and the equipment attendent stationed in the vicinity of the vent valve. All three personnel were contaminated and the equipment attendent received a~second degree burn (about two' inches in diameter) on one arm.

One engineer-located in'the-vicinity of-the vent valve called the control room to report the-leak. The Unit NSO in the control room received the _ engineer's phone call, immediately noted a decrease in the PZR level indication and closed both isolation valves, terminating the event.. After the event, the licensee proceeded to decontaminate the_three personnel-

stationed at the vent valve and dispatched the equipment attendent'

to the hospital to have the burned arm attended to. Approximately four hours after the event the licensee made a courtesy telephone-call to the NRC over the ENS system.

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AIT Formation

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i On October 4, 1990, based on tne information provided from the licensee's courtesy telephone call-and information gathered on site by the Resident Inspector, senior NRC managers in Headquarters and in Region III determined that a sufficient basis existed to form an Augmented Inspection Team. The basis for this decision was primarily the potential for an Intersystem Loss of Coolant. Accident and an apparent breakdown in the control of surveillance. testing activities.

The selection for the AIT included W.'D. Shafer, Chief, Projects Branch 1, Team Leader, W. J. Kropp, Senior Resident Inspector, Byron, S.- G. DuPont,, Senior Resident Inspector, Dresden, S. P. Sands, Licensing Project Manager, NRR, E. A. Trager, Jr.,,

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Reactor Operations Analysis Branch, AE00,15. Diab, Risk Assessment Branch, NRR, and J. L. Harbour, Idaho National Engineering Laboratory.

The team selection was based on.providing the appropriate _ expertise to address the areas of.intersystem LOCA potential, event _ analysis, and loss of command and control'of surveillance testing activities.

C.

AIT Charter On October 4,1990, Region III formulated 'and provided to the' AIT a charter for implementation.

The approved charter was provided to the Team Leader for_ distribution to the team members'at the site.

The AIT Charter is Attachment 1 to this report.

The general areas-to be investigated were:

i Develop and validate the sequence of events.

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Evaluate the adequacy of the licensee's. response, immediate

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corrective action, and subsequent investigation.

Determine root cause for the opening of the RHR Hot Leg l Isolation

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Valve vith the RHR Suct!on Line Vent Valve open.

Determine and validate flow path and volume of fluid loss.

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Assess operator performance, supervisory overview, and procedure i

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adequacy.

Determine the adequacy of procedures, communications, and-

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administrative controls for coordinating surveillance testing activities.

Review the loss of coolant event of March 18, 1990, described-

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in IR'50-457/90012 and this event for similarities and determine-if the associated corrective actions should have prevented the October 4, 1990 event.

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persons Contacted

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Commonwealth tdison Company (Ceco)

• K. L. Kofron,.Statio. Manager

• K. L. Graesser, G',neral Manager, PWR Operations A. R. Checca, Nelear Licensing Administrator

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'D. E. O'Brien, Technical Superintendent

• G. E. Groth, Production Superintendent

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R. D. Kyrouac, NQP Superintendent.

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• K. G. Bartes, ONS Administrator R. A. Flessner, Office of Vice President

• J. J. Gilmore, Assessment, Corporate

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G. R. Masters, Assistant Superintendent - Operations

• D. J. Miller, Regulatory Assurance Supervisor

• P. A. Smith, Unit 1 Operating Engineer i

"D. E. Cooper, Technical Staf f Supervisor i

• J. M. Watson, Nuclear Quality Programs-Engineer

E. W. Carroll, Regulatory Assurance-

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• D. A. Adams, Performance Assessment-P. Holland, Regulatory Assurance T. W. Simpkin, Regulatory Assurance

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'J. D. Wagner, Regulatory Assurance P. A. Lau, Regulatory Assurance D. Noum, Performance Assessment

• J. Gilmore, OPEY

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' Denotes those attending the exit' interview conducted on.0ctober 6, 1990,

i In addition, other members of the Braidwood staff were contacted by the AIT members, i

II.

Description - Unit 1. Loss of Reactor Coolant Inventory to the Auxiliary

- I Building during surveillance testing on the B RHR Suction Line on I

October 4, 1990.

I A.

Narrative Description

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On October 4, 1990, at approximately 1:22 a.m. (CDT), an equipment l

attendent and two engineers were sprayed'with reactor coolant water-with the RCS system at 360 psig and 180*F. ' An isolation valve in

the Residual Heat Removal (RHR): system was opened for a stroke time l

surveillance test while a vent valve on the same line was still open as a result of the licensee concurrently performing a leak surveillance test.

At the time of the event, Unit I was in Mode 5,.

Cold Shutdown. As a result of this event, approximately 600. gallons of reactor coolant was released to-the Auxiliary Building'through-vent valve RH0288.

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B.

Sequence of Events

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I October 3, 1990 j

At 7:00 a.m., the Operating Engineer determined that technical staff surveillance BwVS 4.6.2.2-1, " Isolation Leak Rate Test,"

would be performed prior to draining the remaining two steam generators on Unit 1.

At 9:00 a.m., the Technical Staff Primary Group Leader:was

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requested to select the cold shutdown valve stroke surveillances

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(BwVS 0.5-2.RH.2-1) to be performed concurrently with BwVS 4.6.2.2-1.

i In addition, engineers ~were selected to perform BwVS 4.6.2.2-1.

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At 10:00 a.m., the selected engineers met to develop testing i

strategies and prepare for testing RHR Train A on Shifts.2 (days)

l through 3 (evenings) on October 3 and Train B during Shift 2 on

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October 4.

An additional engineer was called in from the training center to-

'i replace one of the originally selected engineers at about 12:00 noon..

Between 1:00 p.m. and 2:00 p.m., the group leader and the informally selected test director attended a meeting-on loop check i

valves. This meeting was a priority (attendance required), but

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unrelated to the efforts associated with BwVS 4.6.2.2-1.

Between 2:00 p.m. and 3:00 p.m., BwVS 4.6.2.2-1 was identified to the technical staff by the Operating Engineer and Work Planning as

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i being the critical path requiring continuous coverage until completed. This decision resulted in the testing of train B during Shift 1 (nights) on October 4, 1990.

At 2:30 p.m., the technical staff engineer (TSE) briefed Operations

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Shift 2 on the testing and received the-Shift Control Room ~ Engineer:

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(SCRE) signature / approval-to commence testing per BwVS'4.6.2.2-1.

However, actual testing was held until after 4:00 p.m. for shif t l

turnover.

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i BwVS 4.6.2.2-1 was discussed during the 3:15 p.m., Shift.3 briefing.

Between 3:30 p.m. and 5:17 p.m., the SCRE on Shift 3 approved for

performance three cold shutdown valve stroke tests.-

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At 4:45 p.m., BwVS 4.6.2.2-1 testing commenced on Train A.

At 9:00 p.m., the technical ~ staff engineers decided that the relief crew was not needed to complete the surveillances.

At 10:00 p.m., the relief crew was notified not to come in.

About 11:00 p.m., the Train A portions of BwVS'4.6.2.2-1, 0.5-2.RH.2-1 and 0.5-2 RH.2-2 were completed and RHR' trains were swapped to allow testing on Train B.

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At 11:42 p.m., the RHR' Train B pump was placed in pull to lock and

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BwVS 4.6.2.2-1 was started on Train B.

October 4, 1990 Between 1:13 a.m. and 1:16 a.m., the TSEs at the Auxiliary Building 364 elevation reported zero leakage per BwVS 4.6.2.2-1, step 2.20.

The TSEs in the control room directed the TSE at the 364 elevation to close vent valve RH028B and to rehang the out-of-service.

The TSE at the local station directed the equipment attendant to'close

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RH0288.

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At about 1:17 a.m., a second TSE in the contcol-room requested the

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Auxiliary NSO to open RH8702B per BwVS-0.5-2 RH.2-1.

The Auxiliary

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NSO opened RH87028.

Between 1:17 a.m. and -1:22 a.m.., the equi.pment attendant,: while.

closing RH0288, heard a rush of_ water through the tygon hose-connected to RH0288 and attempted to rapidly clo'se the vent valve.

The tygon hose ruptured under 360 psi pressure,; contaminating -the equipment attendant and the two TSEs (the equipment attendant also

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received a second degree burn to the left forearm).

One of the TSEs at the 364 elevation! notified the control room of the primary coolant leak.

The Unit NSO noticed a 5 percent pressurizer level decrease

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(indication of a loss of approximately 600 gallons of coolant) and.

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took both isolation valves, RH8702A and RH8702B, to close.

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At 1:23 a.m., RH8702A.and RH8702B closed and the loss of coolant

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event was terminated.

C.

Analysi s The team reconstructed and validated the sequence of events associated with this loss'of reactor coolant inventory. The team used various logs, the licensee's summary, graphs of various

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parameters and interviews with various personnel. The' team found general agreement between the data and their perception of the event except for the actual time that.both'the RH928B'-(vent valve);

and RH8702B (isolation valve) valves were open initiating the. loss of reactor coolant.

III. Investigative Efforts A.

Operations Department Involvement

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To assess the involvement of the. Operations' Department in then i

event, the AIT interviewed personnel' involved in the event and reviewed the following documents:

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i BwAp 100-8, Revision 0, " Proper Signing and-Initiating of,

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Records".

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BwAp 300-1, Revision 3, " Conduct of Operations".

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BwAP 340-1, Revision 6, "Use of Procedures of Operating.

• Department".

BwVS 0.5.2.RH.2-1, Revision 3, " Residual Heat Removal Valve

Stroke Test".

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BwVS 4.6.2.2-1, Revision 4, " Reactor Coolant System Pressure

Isolation Valve Leakage".

SCRE Turnover Sheet (Shift 3-1).

• SE Turnover Sheet (Sh'ift 3-1),

(1) Operational Department Irvolvement-

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The Operation Staff ~on shift (Shift 1 - 11:00 p.m. to 7:00 a.m.) at the time of the event included the Shift Control Room Engineer (SCRE),-the Unit 1 licensed. Nuclear Station Operator (NS0), another Auxiliary NSO, the Shift Engineer (SE), a Shift Advisor (SA), and a Equipment Attendent (EA). Also in the-main control room were two Technical Staff Engineers (TSE #1-and #2) who were assigned to parform the two surveillances.

• BwVS 4.6.2.2-1, and BwVS 0.5-2 RH.2-1.

The EA and'two other TSEs (#3 and #4) were positionrd in the-Auxiliary Building, Elevation 364', to open and c1ose vent valve'RH028B when required by surveillance procedure, BwVS 4,6.2.2-1, andcto measure any leakage from the RH028B usina a graduated-

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container.

TSE #4 was in training and.his involvement wasL

'imited to observing the test. Operation of RH028B required

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the EA to climb up a ladder.and cross a cable tray. The

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Auxiliary NSO, in addition to the surveillance. testing, was responsible for monitoring reactor coolant. system parameters.

The Unit 1 NSO was-not actively involved in the performance of the two surveillances.

Shift 3 (3:00 p.m. t'o 11:00 p.m.')

o operations personnel along with TSEs #1, #2, #3,:and #4-had completed surveillances BwVS~4.6.2.2-1 and BwVS'0.5-2.RH.2-1, for Train A components.

Prior to: shift turnover, Shift 3 personnel had. swapped RHR trains for shutdown cooling from Train B to Train A in preparation for testing the Train B components on Shift 1.

Interviews with Shift 1' personnel determined that the SE,.SCRE, Unit 1 NSO and.SA were unaware that surveillance BwVS 0.5-2.RH.2-1, stroke testing of.the RHR hot leg suction valves was being performed. concurrently with surveillance BwVS 4.6.2.2-1.

The Auxiliary-NSO appears to have been the only operations' individual on shift that was; aware the two surveillances were being performed concurrently.

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...

i T

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(2) Briefinos

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The administrative controls for shif t turnover ac*,vities were t

reviewed by the AIT since the on-shift ~operationai staff (SE, R

SCRE, Unit NSO and SA) were. unaware that both the leakage.

'

and stroke surveillance tests were being performed concurrently.

These individuals were. aware of the performance of the leakage surveillance (BwVS 4.6.2.2-1).

TSE #1 had.

informed the SCRE of the leakage surveillance prior to commencing Train B testing'on Shift 1.-.However, TSE #1 informed the SCRE verbally with only surveillance pNcedure BwVS 4.6.2.2-1 in hand and did not clearly stipulate that the-

other surveillance, BwVS 0.5-2.RH.2-1 was also planned to be performed at the same time.

.

A review of the executed surveillance packages, BwVS 0.5-2.RH.2-1 and 4.6.2.2-1 determined that the authorization to

<

start the surveillances was obtained and documented on previous shif ts. - BwVS 4.6.2.2-1 authorization was obtained.

from the SCRE on Shift 2 and authorization for BwVS 0.5-2.RH.2-1 was obtained from-the SCRE on Shift 3.

There were no administrative controls established that required a~

re-authorization to start a surveillance initially authorized-on an earlier shift.

The AIT also reviewed.the SE and SCRE shift-turnover sheets.

Neither surveillance, BwVS 0.5-2,RH.2-l'or BwVS 4.6.2.2-1 were Identified as.on going work on the Shift 3 to Shift 1 turnover shets.

(3) Degree of Involvement Awareness

!

The'AIT assessed the degree of involvement and awareness of

the individuals involved-in the execution of the

!

surveillances.

Task involvement pertained to the degree individuals directly' participated in executing the various steps of the two surveillances. Awareness pertains to the extent individuals were aware of changes in the RHR system configuration based on execution of the surveillance steps.

The AIT identified three levels of involvement / awareness:

'

high, medium, and low.

Based on this categorization,

!

individuals were assigned to each level.

The SE, SCRE, Unit NSO and SA did not participate in the execution of the surveillances and was classified as low involvement / awareness by the AIT.

However, since the SE, SCRE, l

Unit NSO and SA were unaware that-the stroke surveillance was-i being executed, any opportunity to ensure the surveillances

'

were properly coordinated was lost.

.

The Auxiliary NSO, EA, TSE #3 and TSE #4 had a moderate level of involvement / awareness.

'

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,

.

.m

.

4

'Although, these individuals were directly'. involved in-

-

executing some of the steps of the two surveillances, the'

scope of involvement for the EA, TSE #3 ano TSE #4 consisted i

of the opening and closing of vent. valve RH0288, and the i

measurement of RCS leakage when directed by the TSEs in the main control room.

These individuals were not continuously aware of the status of the RHR system, such as when valves RH8702A and RH8702B were repositioned for stroke timing.

These evolutions were not communicated to the personnel._at the local station by the TSEs in the main control room. The;

Auxiliary NSO was considered only moderately _ involved because involvement was limited to opening and closing valves RH8702A and RHS702B at various steps.in the surveillance procedures.

The Auxilary NSO was not cognizant of the' execution of the

,

surveillance steps and did not have at all-times a continuous j

knowledge of the RHR system configuration.

The Auxiliary NSO

was implementing various steps of the_ surveillance procedures,

'

as directed by TSE #1 and #2, and was not'in the direct-communication link with the personnel in plant.

TSE #1 and #2 had high involvement / awareness of the execution ~

I of the two surveillances collectively, and were involved in:

1) monitoring all steps of the two surveillances, 2) issuin'g directions to execute surveillance steps, 3)-the performance-of leakage calculations, 4) signoff of_ completed steps, 5)

providing communication links between individuals executing the surveillances and 6) monitoring all changes in RHR system

-

configuration.

However, at various times, the degree of involvement / awareness of TSE #1 and #2 varied, :such as the 1 time of the event when TSE #2 was unaware that TSE #1: directed.

the Auxiliary NSO to open valve RH8702B, prior'to verification of the closure of vent valve RH0288.

!

(4) Conclusions Based on the above information, the.AIT identified several weaknesses in the conduct of surveillances in the operations area. The following weaknesses were identified:

Communications prior to and during the event'were

,

inadequate.

Shift turnovers did not address or identify ^

,

on going surveillances. _ The Unit and Auxi,11ary-NS0s did not communicate manipulations of the systems-between themselves or with the SCRE.~

Operations Department logs.

,

and turnover sheets did not identify appropolate testing.

-!

activities.

,

The Auxiliary NSO who participated in the execution: of,the

i two surveillances was not cognizant of the status of!the

'

configuration of the kr.R system at all times. The cause-appeared to be the Auxiliary NSO was not totally integrated i

into the execution of the two surveillances, i

i

l

.

. I

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t The Auxiliary NSO allowed the TSEs to direct the

-

manipulation of system components during the performance of the surveillances.

The EA and TSEs in the Auxiliary Building who were opening

-

and closing vent valve RH028B, were also not integrated into the execution of both surveillances.

These individuals were limited in the knowledge uf the RHR system configuration since

'

communications with the main control room was limited to I

execution of specific surveillance steps.

!

B.

Technical Staff Involvement To assess the involvement of the Technical Staff in the event, tr.2

AIT interviewed personnel involved in the event and reviewed the associated surveillances, BwVS 4.6.2.2-1, 0.5-2.RH.2-1, O. 5-2. RH.2-2, a nd 0. 5-2. 51. 2-2.

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(1). Narrative of Technical Staff Involvement

'

On October 3, 1990, the Technical Staff was reviewing the various code requirements for leak testing and valve stroke timing while in cold shutdown (Mode 5).

The codes required initiation of leak tests af ter the unit was in Mode 5 for

greater than 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> and stroke testing of valves when in Mode 5 for greater then 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br />.

The technical staff had the lead responsibility for both the leak and valve stroke testing.

i

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During the morning technical staff meeting, the Acting

,

l Technical Staff Supervisor indicated that the technical staff

!

should prepare to perform BwVS 4.6.2.2-1, " Reactor Coolant

'

tystem Pressure Isolation Valve Leakage Surveillance." Additional j

discussions determined that if the_ unit was to make a pending l

mode change, then only 3 of the 11 sections (affecting the RHR t

I and SI systems) would need to be performed instead of all 11 sections. The initial plans were to perform the three sections on one of the two trains of RHR d wing Shift 3 on October 3 and the remaining train during Shift 2 on October 4.

Af ter the Acting Technical Staff Supervisor determined that a mode change would not occur, the decision was made to perform all sections and to start during,%ift 2 on October 3.

This decision did not, however, include strategies for continuous testing. The Primary Group Leader assigned the performance of BwVS 4.6.2.2-1 to three TSEs and a trainee. The initial planning and preparation included determining what out of i

services would need temporary lifting to perform testing on

'

the RHR "A" t rain.

(The current condition of Unit I had the-

"B" train operating for decay heat removal and the "A" train in standby.)

'

'

.

'

About mid-morning on October 3, +be Operating Engineer (acting i

.

for both Units 1 and 2) with Work Planning determined that

'

prior to draining the remaining two steam generators (two had been previously drained) in-support of post modification testing on the Auxiliary Feedwater System, BwVS 4.6.2.2-1 would be performed continuously until completed. Based upon the Operating Engineer's previous experience, about 16 hours1.851852e-4 days <br />0.00444 hours <br />2.645503e-5 weeks <br />6.088e-6 months <br /> would be needed to accomplish the testing including planning and preparation, it should be noted that the performance of BwVS 4.6.2.2-1 was not a prerequisite for either draining the steam generators or parforming the Auxiliary Feedwater Testing.

In addition, if BwVS 4.6.2.2-1 was performed af ter the steam generator draining and Auxiliary Feedwater testing, the refilling of the steam generators would become the critical path and possibly delay the scheduled returning.

of the unit back to service on October 6 by at least eight

-

hours.

This decision was communicated to the Technical Staff at about 2:00 p.m. followed by a discussion between the

,

Operating Engineer, Work Planning, Technical Staff Primary Group Leader, Assistant Technical Staff Supervisor, and the Acting Technical Staff Supervisor. The discussion included the concerns of the technical staff with the difficulties of supporting continuous. testing due to personnel shortages and that preparations had only been done for the RHR Train A.

However, the decision was made not to change the schedule and wat the technical staff would support the schedule.

The Primary Group Leader was also assigned by the Acting Technical Staff Supervisor to determine what celd shutdown valve stroke testing would be performed concurrently with BwVS 4.6.2.2-1.

Since BwVS 4.6.2.2-1 positioned many of the RHR and Safety Injection (SI) valves, the stroke testing would only require timing of those valves during the positioning per-BwVS 4.6.2.2-1.

The group leader subsequently determined that

.

three additional tests could be performed concurrently with BwVS 4.6.2.2-1.

These included BwVS 0.5-2.SI.2-2, " Safety l

Injection System and SVAG Valve Stroke Test," BwVS

'

O.5-2,RH.2-1, " Residual Heat Removal Valve Stroke Test," and BwVS 0.5-2,RH.2-2, "RHR Check Valve Stroke Test." One of the

-

TSEs assigned to perform the BwVS 4.6.2.2-1 surveillance was

!

informally selected to function as a test director in addition I

.

'

to performing most of these tests. This TSE notified the Shift 2 SCRE of the performance of BwVS 4.6.2.2-1.

f The SCRE approved BwVS 4.6.2.2-1 for performance at 2:35 p.m.,

but delayed actual starting of the surveillance until after l

the turnover between the day shift and the evening shift (Shift 3).

Subsequently, the Shif t 3 SCRE approved surveillances BwVS 0.5-2.SI.2-2, 0,5-2.RH.2-1 and 0.5-2.RH.2-2 for performance.

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In addition to the above efforts, the Primary Group Leader

.

adjusted the assignments of engineers in an attempt to support continuous testing. These efforts were to limit the

'

engineers on Shifts 2 and 3 to between 16 and 18 hours2.083333e-4 days <br />0.005 hours <br />2.97619e-5 weeks <br />6.849e-6 months <br /> of continuous work and to be replaced by a relief crew (the

',

relief crew would have worked two periods of eight hours with a break of about five hours).

.

Actual testing began at about 4:45 p.m. (Shift 3) on RHR Train A.

The three valve stroke tests were approved for performance between 3:30 p.m. and 5:17 p.m.

At about 6:30 p.m. discussions between the Primary Group Leader and Work Planning were held in the Shift Engineer's Office and via telecommunications with the Operating Engineer on the performance of one of the three valve stroke tests. Through

,

this discussion, the. determination was made not to perform BwVS

0.5-2.SI.2-1 on the safety injection valves based upon the potential for delaying the steam generator draining evolution.

The valve stroke tests for the RHR isolation valves were not discussed.

The RHR Train A portions of the surveillances were complued at about 11:00 p.m. on October 3.

With the exception of missing the stroke timing of one Train A isolation valve, the testing was successful.

Subsequently, that stroke test

'

was completed prior to testing Train B.

At about 1:10 a.m. (October 4), the finci steps of BwVS 4.6.2.2-1 and 0.5-2.RH.2-1 were being performed.

Prior to confirming that RH028B was closed, the TSE performing the test directing function requested the Auxiliary NSO to open and stroke time RH8702B per the valve stroke test.

This resulted in establishing a flow path through both RHR suction isolation

'

valves and the open vent valve.

Although the EA operating RH028B attempted to close the vent valve, the tygon tube'

ruptured and contaminated the EA and TSEs at the local

,

'

t station.

After the local station communicated the loss of

'

coolant, the Unit NSO immediately closed both RHR suction'

'

valves terminating the event.

The loss of coolant event lasted for an estimated five minutes.

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(2) Execution of Surveillances

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The station's technical staff was responsible for ensuring the

!

surveillances, BwVS 0.5-2.RH.2-1 and 4.6.2.2-1, were performed i

in accordance with the surveillance procedures during the established forced outage schedule.

The two surveillances were compatible and could be executed.

No individual interviewed could remember performing the two surveillances concurrently prior to March 3-4, 1990. Although.the execution of each surveillance separately would be considered a

'

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.

.

rule-based behavior (e.g. behavior where a person follows a

.

step by step task), the coordination and execution of both procedures concurrently was considered a knowledge based behavior that required an individual.to plan actions based on an analysis of the function and status of a system.

Therefore,

the execution of both surveillances concurrently was more difficult to execute successfully.

The type of coordination effort is referred to as a dynamic task that requires a higher degree of interactio9 between personnel performing the task

.

,

and awareness of system status.

Dynamic tasks m&y involve decision making, the tracking of several functions simultaneously, or any combination of these. The increased

,

complexity of perfirming both surveillances concurrently was substantiated by tLe Auxiliary NSO who stated that at various times the execution of the surveillances prior to the event on

,

Shift I was momentarily delayed to assess the status of the surveillances.

Also, during the performance of the two

-

surveillances on Train A componamts on Shift 3, a step for timing the stroke on a valve was missed and had to be re performed.

'

(3) Conclusions Based on the above information, the AIT identified several weaknesses in the conduct and preparation of surveillances in the technical support area.

The following weaknesses were identified in order of significance:

.

Control of the hours worked by the TSEs was inadequate.

• Formal controls were not established to either li'.it the TSEs to reasonable working hours (actual time of work for all associated TSEs were between 18 and 20 hours2.314815e-4 days <br />0.00556 hours <br />3.306878e-5 weeks <br />7.61e-6 months <br /> prior to-the event) or to require supervision's evaluation and approval to extend testing without using the relief crew. The AIT noted that no regulatory requirements exist on these type of controls.

'

Although the two surveillances were compatible,

!

inadequate communications and control between the two TSEs in the control room existed prior to and during the event.

This was demonstrated by the missed stroke timing of one valve on Train A and the actual event on Train B.

!

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Control of testing was further complicated by the

informal determination that one of the TSEs was to also function as test director coordinating the entry points of the cold shutdown valve stroke tests into the leak test.

Since the responsibilities associated with test directing were not formally assigned or fully understood, communications and coa;rol between the two TSEs in the control room were not effective, and resulted in a decreased awareness between the TSEs during an evolution r

that required a high level of involvement and awareness.

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i e

j The performance of the cold shutdown valve stroke

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surveillance 5 were not required per Technical Specifications or as prerequisites to either the draining of steam generators or post modification testing of the

'

Auxiliary Feedwater system. As such, the scheduling of these tests concurrent y with the RHR leak tests should l

,

have required an evaluation for the need of increased coordination due to the potential associated with high to low pressure interfaced systems.

l C.

Work Planning Involvement

,

I l

The area of work planning was reviewed to assess if there was a i

positive mechanism to ensure the oncoming operating shift was informed oi *11 the surveillances which were being performed by the

,

l t*chnical staff.

Interviews with the technical staff, operators, work planners, and station control room engineer were conducted on October 5 and 6 to establish the actions of the personnel involved, the primary causes of any inappropriate actions and the corrective actions under consideration.

In reviewing the work planning aspects of this event, it was concluded that there were a number of contributing factors which-had an impact on this event.

First, thure was poor communict.tions between the work planning group and the technical staff, in that the technical staff was supposed to get back to the work planner j

with any additional surveillances that needed to be ucomplished.

i Neither department communicated with the other afte' the_ initial

'

discussion to confirm if any additional testing was to be performed.

Second, the work k. 1ning group did not complete a revised schedule showing the test changes until the end of the day (October 3) and did not distribf.e the new/ revised schedule until the next morning (October 4), All of the schedule changes were accomplished by verbal communications between the Operati'.g Engineer and the technical staff.

At no time was the stroke time surveillance discussed with the shifts, Work Planning Department, or the Operating Engineer.

In conclusion, communications between departments and work organization / coordination to ensure schedule updates were ineffective.

l D.

Intersystem Loss of Coolant Accident (ISLOCA) Potential

1.

Introduction An ISLOCA is a class of events where a low pressure system is

accidentally subjected to primary reactor water at high

pressures, and an unisolable leak (or break) is developed.

'

An ISLOCA becomes of particular concern if the unisolable

1

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g 1eak/ break takes place outside the containment.

In that case

the loss of water inventory cannot be recovered for long term core cooling. Also, the leakage path will transfer any contaminants and fission products directly outside the

,

containment and potentially offsite.

During this event, the RHR system pressure boundary had not been challenged because the surveillance tests involved in the incident are only allowed during Mode 5 operation when the RCS pressure is below the code allowable for this piping. The RHR suction piping design pressure is 600 psig.

Had the vent valve not been capable of being closed for any reason, the RHR suction line has two isolation valves and closure of either valve would terminate the event.

The potential for an ISLOCA on the RHR suction line exists due

.

to the high/ low pressure interface.

However, the system is

designed to minim 12e this interface problem.

The two isolation

-

valves have permissives which prevent the valves from opening at RCS pressures above 360 psig.

In the event of leakage past

'

these two valves, the suction line contains a relief valve that opens at 450 psig to prevent the line from exceeding the code allowable pressure for this piping.

Should the relief valve fail, the two isolation valves will auto close at 662 psig.

It should be noted that this auto close interlock function will be removed during the next refueling outage in accordance with a Technical Specification amendment.

Some of the causal factors that contributed to the October 4, 1990 event could also contribute to an ISLOCA, particularly the loss of command and control of surveillance activities by the operating line organization and the decision to conduct two surveillance tests concurrently. While these tests were compatible, they were not sufficiently integrated to preclude or minimize the possibility for personnel error.

Based on the above considerations, the' team concluded that the October 4, 1990 event was not an intersystem loss of coolant accident.

However, the act of conducting multiple surveillances on systems with a low /high pressure interface, coupled with the loss of command and control by the Operating Department, is considered a precursor to an ISLOCA.

IV.

Licensee Investigation On October 4,1990, Region III issued a Confirmatory Action Letter (RIII-90-019) indicating that the licensee would conduct an independent investigation to determine the root cause of the loss of reactor coolant i

system inventory event on October 4, 1990, and as a minimum, would include an evaluation of the sequence of events that permitted this problem to occur including consideration of the adequacy of supervision

,

to control work activities, adequacy of applicable procedures and the i

capability of the personnel involved to perform their duties.

_ _ _ _ _ _ - _ _ _ _

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%

A.

AIT Evaluation of the Licensee's Investication

.

On October 5 and 6, 1990, the Team Leader and other team members met with the licensee's investigation team to evaluate the adequacy of the ongoing investigation.

The licensee's investigation team determined that the proximate cause for the loss of reactor coolant system inventory was the failure to close vent valve RH0288 prior to opening isolation valve RH87028 for stroke testing. The licensee's preliminary information indicated that three inappropriate. actions had occurred that contributed to this event.

1.

The Technical Staff Engineer directed the NSO to open the RHR isolation suction valve with the RHR vent valve still open. The primary causes that appeared to have contributed to this inappropriate action were the amount of overtime the Technical Staff Engineer had worked at the time of the event and that the Technical Staff Engineer had inappropriately transitioned from the leak test surveillance procedure to the stroke time test surveillance procedure at the incorrect step in the leak test procedure.

2.

The second inappropriate action was that the NSO in the control room opened the RHR isolation suction valve RH8702B while vent valve RH028B was still open. The primary causes contributing to this action were that the NSO and the Technical Staff Engineer failed to track the status of the task given to the equipment attendent (to close the vent valve), and that no policy existed to allow the

!

Technical Staff to direct operating activities.

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3.

The third inappropriate action was that the stroke valve test procedure (BwvS 0.5-2.RH.2-1) was not placed on the forced outage schedule of work developed by the Work Planning Group.

B.

Conclusions The AIT determined that the sequence of events developed by the licensee and used to make their preliminary findings adequately represented their understanding of the event as of October 6, 1990 ( Attachment 2).

The licensee's investigation of the event was continuing at the time the AIT completed the onsite portion of the inspection effort.

19 a

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V.

Comparison of the March 18, 1990 Braidwood Loss of Coolant Event to the

.

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Detober 4, 1990 Event

'

A.

The March 18, 1990 Event

.

A review of the March 18, 1990 Braidwood Loss of Coolant Event (IR 50-457/90012) revealed that the root cause of inadvertant-

'

transfer of 9800 gallons of RCS inventory to the RWST was due to a

lack of communications between the SCRE and the Unit 2 NSO.

,

There appeared to be several factors which contributed to th'c

,

event.

One was a communications culture in the control room that

permitted the NSO to operate systems without informing the SCRE.

The inspection determined that in Mode 5, when many systems are in abnormal configurations with numerous evolutions in progress, the SCRE needs to be kept informed of system lineup changes. A second contributing factor to the event was related to procedural deficiencies.

The corrective action developed by the licensee was the issuance-

.

of Special Operating Order No. 50-ST-0039 Hightened Level of Awareness (HLA) of Control Room Activities (Attachment 3).

The

,

Special Operating Order (500) describes the minimum acceptable level of discussions that will occur prior to any non-routine or infrequent activity or event performed by control room personnel.

,

The responsibility for implementing this S00 was placed on the Shift Engineer /SCRE. Appendix A to the 500 lists those activities

-

that require the application of a HLA and includes " operations

'

involving manipulation of system isolations between high and low

~

pressure systems" and "any evolutions involving the RH train such as recircing, placing in shutdown cooling, swapping train to train or filling or draining the reactor cavity." The 500 further specifies that the Appendix A list is not all inclusive and can be modified or added to as necessary by the SE/SCRE.

'

B.

The October 4, 1990 Event The proximate cause of this event was the premature opening of valve RH8702B prior to ensuring that vent valve RH028B was closed.

Step 2.15 of procedure BwVS 4.6.2.2-1, RCS Pressure Isolation Valve Leakage Surveillance, requires closure of RH028B and signoff to confirm the step was accomplished.

However, prior to completion of this step, the licensee transitioned to step 4.3 in procedure BwVS 0.5-2.RH.2-1, RHR Valve Stroke Test, which required the opening

',

of valve RH8702B and documentation of the stroke time, i

The team determined that the October 4, 1990 event proximate cause resulted from several causal-factors.

The first factor was the

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amount of overtime involving the Technical' Staff Engineers. The

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f i

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second factor was the conducting of two surveillance procedures

,

concurrently, which while compatible, requires significant coordination and communications. The third factor was the fact that the t

Operations Department line organization was not aware that the stroke valve surveillance was being accomplished concurrently with the valve leakage testing,

,

C.

Conclusions

,'

l The HLA corrective action implemented by the licensee as a result I

of the March 18, 1990 event had not been implemented during the l

October 4, 1990 event as required by $0-ST-0039, Heightened Level i

of Awareness.

Reportedly, licensee interviews with the SE and SCRE f

(

on the second shift (afternoons) indicated that the HLA concept had been invoked at the beginning of that shift; however, the log books i

and shift turnover records were silent.

The SE/SCRE on duty during-the event did not invoke the HLA concept.

Had the HLA program been implemented, the Heightened Level of Awareness of the operating

,

crew may have preventea the October 4, 1990 event.

VI. Safety S_ignificance of_the Event

'

The unit was in Mode 5, cold shutdown, which is a prerequisite for conducting the surveillance testing that was being accomplished when the

'

[

event occurred. While the immediate safety of the workers at the site

of the vent valve was challenged, there was no challenge to the plant

that could not be compenseted.

The safety significance of the event t

(

was minimal,

,

VII. AIT Concerns and Recommendations A.

Concerns

,

1.

The NSO allowed the Technical Staff Engineer to direct the manipulation of valves in the field and in the control room

during the surveillance activities.

2.

The SE, SCRE, SA, and Unit NSO were unaware of the stroke time surveillance test.

3.

The Work Planning Group was not aware that the stroke time surveillance test would be performed, o

4.

The crew at the local station was not informed that valve RH8702B would be opened for stroke time testing.

>

5.

The operating logs and_ turnover sheets were mute on the

,

performance of the valve stroke tests.

'

6.

The TSEs cancelled the use of the relief crew without I

approval from supervision.

.

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i l

7.

A communications culture existed in the control room that

.

permitted the Auxiliary NSO to perform surveillance without

informing the SCRE. A similar problem with communications was identified previously during the March 18, 1990 event.

'

B.

Recommendations The licensee should meet with NRC Regional Management to discuss

)

the results of their independent investigation and to present the measures they will take to reduce the potential for loss of command and control of the station activities by the operating line organization.

VIII. AIT Charter Completion The AIT finds the sequence of events, as developed by the licensee and the AIT using available records and documents including logs, computer printouts, charts, graphs, and surveillance procedures, coupled with

.

interviews of the individuals involved in the event, is a valid description of the incident.

As noted in Section 11 and III, the team concluded that the licensee's actions in response to the incident were acceptable and timely in terminating the event.

The team concluded that the root cause of the event was the premature opening of isolation valve RH8702B while vent valve RH028B was still

'open.

In addition, review of available records confirmed that approximately 600 gallons of RCS coolant exited vent valve RH028B and spilled onto the Auxiliary Building floor.

The team concluded that the NS0's performance prior to and during the event was unacceptable in that the Technical Staff Engineer was allowed to direct the manipulation of valves in the field and in the control ronn.

Shift supervision prior to and during the event was inadequate dvs to the lack of awareness that the stroke time surveillance test was being conducted.

The AIT concluded that the surveillance test procedures used to perform the tests were adequate and could be performed concurrently.

However, fatigue of the Technical Staff Engineer coupled with the loss of awareness by the operating crew resulted in inadequate test implementation.

Finally, the team concluded that had a heightened level of awareness been invoked as required by the Special Operating Order, the October 4, 1990 loss of RCS inventory could have been prevented.

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IX.

Exit Interview (30703)

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The inspectors met with the lic,ensee representatives (denoted in Paragraph I.D.) throughout the inspection and evaluation of the events and at the conclusion on October 6, 1990.

The team summarized the scope and findings of the Augmented Inspection Team's activities. The licensee acknowledged these findings. The inspectors also discussed the likely informational contents of the inspection report with regard to documents or processes reviewed by the inspector during the inspection. The licensee did not identify any documents or processes as proprietary.

During the exit, the licensee identified the following interim corrective actions:

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The CECO policy on overtime (Commonwealth Edison's interpretation c '

the NRC policy) will be invoked on all station personnel until a thorough review of overtime usage can be completed.

2.

Technical Staff guidance will be issued to control multiple surveillance evolutions.

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3.

Any surveillance steps requiring direction of field operations ~com the control room will be directed by the NSO.

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4.

The oncoming SCREs will initial the cover sheets of all surveillances carried over from a previous shif t.

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ATTACHMENT 1

66 880 UNITED STATES

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NUCLEAR REGULATORY COMMISSION

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OCT 041990 t

!!EtiORAtlDUM FOR:

W. D. Shafer, Chief, Reactor Projects Branch 1 (Braidwood AIT Teen Leader)

FRD!!:

Edward G. Greenman, Director, Division of Reactor Projects SUBJECT:

AUGt1EliTED INSPECT 10ft TEAli (A!T) CHARTER

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Enclosed for your inplementation is the Charter for the inspection of the events associated with the Braidwood Unit 1 Loss of RCS inventory which occurred on October 4,1990.

This charter is prepared in accordance with tho flRC Inspection Panual Chapter 0325.

The objectives of the AIT are to conmunicate the facts surrounding this event to Regional and Headquarters management, as well as to identify and communicate any generic safety concerns related to findings and conclusions of the onsite inspection.

If you have any questions regarding implementation of the enclosed Charter, please contact me directly, b-r Edward G. Greenma f Division of Reactor Projects Enclosure: AIT Charter cc w/ enclosure:

A. B. Davis, R111 C. J. Paperiello, Rll!

H. J. Miller, Rlli C. J. Haughney,f4RR Z. A. Zwolinski, NRR J. W. Clifford, EDO t

E. L. Jordan, AE0D C. E. Rossi,flRR R. J. Barrett, flRR

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Augmented Inspection Team (AIT) Charter Braidwood Unit 1 Loss of Reactor Coolant Inventory You and your team are to perform an inspection to accomplish the following:

1.

Develop and validate the sequence of. events associated with-the loss of; reactor coolant inventory that occurred on Unit 1 on October 4, 1990.

2.

Deternine the adequacy of the licensee's -response to this ' event and:

whether the immediate actions taken and subsequent investigation : wa s appropriate.

3.

Independently determine the root cause for the opening.of-the RHR Hot Leg Isolation Valves with the RHR Suction Line Vent Valve open.

Determine and validate the flow path and volume-of water discharged from the RCS to the Auxiliary Building.

5.

Assess the adequacy of operator performance "and supervisory overview during the incident by review of records and logs; and through interviews-with the personnel on duty.

6.

Identify and determine the adequacy of. the applicable operating-procedures, communications, and administrative controls 1for coordinating surveillance testing activities related-to this event.-

7.

Review the loss of coolant event of liarch 18, 1990 described in IR No.

50-547/90012 (DRP) dated April 18, 1990 for similarities and to' determine if the corrective action put in place for.: that ~ event.should have-

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prevented the October 4, 1990 event.

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ATTACHMENT 2

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i TABLE OF ACRONYMS

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AEOD Office for Analysis and Evaluation'of. Operational Data AIT Augmented Inspection Team.

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ASME American Society of Mechanical Engineering ~

e AUX Auxiliary (Duilding)

Bw0P Braidwood Operating Procedure

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CECO Commonwealth Edison Company i

DRP Division of Reactor Projects

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ENS Emergency Notificotion System

GSEP General Site Emergency Plan-i IN NRC Information Notice-

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INPO Institute of Nuclear Power Operations-LOCA Loss of Coolant Accident

MODE 5 Cold Shutdown.

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NOD Nuclear Operations Directives i

NRC Nuclear Regulatory Commission

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NRK Office of Nuclear Reactor. Regulations.

055 Out-of-Service

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PZR Pressurizer

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RCP Reactor Coolant Pump

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RCS Reactor Coolant System RH RHR System Designators

RHR Residual Heat Removal

Rill Region 111 NRC SRI Senior Resident inspector i

Safety Injection

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T Temperature TS Technical Specifications-j W

' Westinghouse

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ATTACHMENT 3 OCT 4 RHR EVENT TIMEL1HE

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PRELIMINARY REV 1

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10/3/90 0700-BwVS 4.6.2.2 1 IDENT!rIED TO BE PERTORMED IN ENTIRETY 0900-TECH STATT PRIMARY GROUP LEADER INFORMED TO SELECT COLD SHUTDOWN VALVE STROKE SURVEILLANCES.

-TECH start SELECTS BwVS 0.5-2.RH.2-1/2, 0.5-2.81.2-2-ENGINEERS ARE SELECTED TO PERTORM 4.6.2.2-1 (TERKO, BEDrORD, i

WESTRICH, LAMBERT)

1000 !DENTIFIED PERSONNEL DEVELOPED STRATEGY.

-4.6.2.2-1 SCHEDULED ON SHIFT 2 OH 10/3 AND COMPLETED ON SHITTS 2/3 OH 10/4.

1200-GRZEMSK! ASSUMES TERKds ROLE AS TECH STArr TEAM MEMBER.

1500-4.6.2.2-1 DETERMINED TO BE CRITICAL PATH (IE CONTINUOUS COVERAGE REQUIRED UNTIL SURVE!LLENCE IS COMPLETED).

-TECH SURVEILLANCE TEAM DIVIDES TO PROVIDE 24 HOUR COVERAGE.

i 1515 4.6.2.2-1 DISCUSSED AT SHITT BRIETING.

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1645-4.6.2.2-1 COMKENCED TOR 1A RH TRAIN.

2100-TECH STATT ENGINEERS DECIDE RELIEF CREW IS NOT NEEDED TO COMPLETE '

i SURVEILLENCE.

I 2200-RELIEF CREW NOTIFIED NOT TO COME IN.

i PRIOR TO 23DO-1A RH PORTION OF 4.6.2.2-1 COMPLETED AND RH TRAINS SNAPPED.

2342-B RH TRAIN PUMP IS PLACED IN PULL TO LOCK. LEAK CHECK Or 1 RH 8702A CONNENCED.

10/4/90 0120-TECH STArr ENGINTER AT 364 ELEVATION REPORTS 0 LEAKAGE FOR STEP 2.20 OF SURVEILLNHCE.

-CONTROL ROOM TECH STArr ENGINEER TELLS TECH STATT AT,,364 ELEV. TO CLOSE RH 028B AND REHANG OOS.

i 0121-CGtTROL ROOM TBCE STAFF MGINEER REQUESTS AUX NSO 'to OPR' dB 8702 B.

i 0122-AUEILIARY RSO OPBS RB 8702 B FOR STROKE TEST PER BwTS 0.5.2.RE.2-1-5% PRESSURIZER LEVEL DROP.

-EQUIP ATTENDANT STARTS CLOSING RH 028 B.

-HOSE FROM RH 028 B BLOWS Orr AND AREA IS SPRAYED.

0123-RH 8702 B CLOSED WHICH TERMINATED EVENT.

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ATTACHMENT 4 towissen S1

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SPE2AL OratATING ORDER

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Special Operating order no.SS ST-003g mov 1 j Rffective Dete 01.M.90

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.i TN: Heightened Level of Awareness (HLA) of

Control Room Activities The purpose of this meno is to enhance the concepts which exist in BwAP 300-1 Conduct of Operations, regarding commincations

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and control of activities. It describe the minimum acceptable level of discussions that will occur prior to any non-routine or infrequent activity or event performed by Control Room Personnel.

This Heightened Level of Awareness will consist of three parts:

1. As a minimum those evolutions or operations related to the

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evolutions identified in Appendix A will have a Heightened l

Level of Awareness applied.

This list is not all inclusive and can be modified or added to as necessary by the SE/SCRE.

2. The SE/SCRE has the responsibility to identify events or (

evolutions which will require a Heightened Level of Awareness by control room personnel.

This list of qualifying events

will be presented at the Shift Briefing for those that are planned to occur during the shif t.- This list will also be t

updated during the Shift as new evolutions are identified.-

The SCRE will maintain this list at his desk. The SE and SCRE will include a discussion of the list during their turnover.

3. The NSO's are tasked with implementing a Heightened Level of Awareness, on all activities on the SCRE's Itst, but are not *

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limited to those events only.

The Heightened level of Awareness should be applied to any additional events or evolutions with which the NSO is unfamiliar, uncomfortable or', @ '

otherwise decides that this level of awareness is app 1 cable.

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The Heightened Level of Awareness is defined as:

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A minimum of two N$0's (unit and' another) must, discuss ',...

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the event or evolution in detail.

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.APPR VI

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SPE3AL OPERhTING M

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Special Operating Oreer so.

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03-!!-90 Rffective Date

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Heightened Level of Awareness (MLA) of

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Control Roon Activities

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There must be a clear understanding of all the actions l

and expected results among those involved in the

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discussion.

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The discussion will include all actions that will be

taken during the event or evolution.

a continuous review or awareness As the event is ongoing,ing expected results are observed

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must be maintained ensur in response to actions taken.

This Heightened Level of Awareness is intended to provide the additional support an individual needs, to assure that infrequent or particularly difficult operations are well

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understood prior to performance of the evoluti?ns.

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Braidwood Station Attachment I

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SPsl2AL OrsmArtuG Ogest

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Bffective Date

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Operations involving manipulation of system isolations between

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high and low pressure systems.

Operations involving CC heat exchangers especially when swapping

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from unit to unit.

Any evolutions involving RH train such as recircing, placing in

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shutdown cooling, swapping train to train or filling or draining

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the Reactor Cavity.

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Upon recommencing procedures that are presently in progress but

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have required little or no operations over a significant time

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Operations involving reduced RCS inventory.

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Solid operations including placing the RCS in a solid condition

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and drawing a bubble in the pressurizer.

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(Finall'

g,pgovtD M.2 4'.3B6-1-(05949/00219)

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ATTACHMENT S-INTERVIEW LIST Direct Participation:

John Chojnicki Shift Engineer Jeff Cailey SCRE-

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Weyne Carlson U 1 NSO

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Brent Radomski Auxiliary NSO Dave Broglia Shift Adviser Tom Nornian

'B' Operator-Chris Bedford Tech. Staff 1 Engineer Phil Westridge Tech Staff Engineer-Dweyne Lambert Tech Staff EA Jim Grzemski Tech Staff Engineer'

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Indirect Association:

Terry Eckert Work Planning-Tec Snider Work Planning JackNeljewaka Tech Staff Gary Bal Tech Staff Roger Francoeur Tech Staff-Ron Yungk Operating Engineer:

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