IR 05000458/1989041

Forwards Summary of 891215 Enforcement Conference Re Findings of Insp Rept 50-458/89-41 & Notice of Violation. Activities That Led to Recirculation Flow Oscillations of 890117 & 18 Discussed

ML20005G210
Person / Time
Site:	River Bend
Issue date:	01/09/1990
From:	Collins S NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION IV)
To:	Deddens J GULF STATES UTILITIES CO.
Shared Package
ML20005G211	List: IR 05000458/1989041 ML20005G217
References
EA-89-232, NUDOCS 9001180287
Download: ML20005G210 (41)

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In' Reply Refer To

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Docket:-- 50-458/89-41; EA No: 89-232

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Gulf States Utilities ATTN:- James C. Deddens

<y SeniorVicePresident(RBNG).

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P.O.?80x 220'

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.St. Francisvilley Louisiana 70775

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Wf Gentlemen:

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SUBJECT: NOTICEOF_ VIOLATION (NRCINSPECTIONREPORTNO. 50-458/89-41)-

This refers to the Enforcement Conference conducted in the NRC Region IV office j',

on December 15, 1989, betweenrepresentativesofGulfStatesUtilities.(GSU)

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.and NRC. This conference was held at the Region's request to discuss the

. findings'of the NRC inspection conducted during the period'Hevember'l-15, 1989,

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I 1989.

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50-458/89a41, dated December 4,-

i which were documented in NRC Inspection Report

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The subjects. discussed'at this meeting relate to the activities that led to the

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recirculation flow esci11ations-of January 17 and 18,1989, at GSU's River Bend

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j Station and the subsequent actions of your staff. The specific issues discussed

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at the meeting' are documented in the enclosed Meeting Summary.

It is our

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p, opinion that this meeting was beneficial and provided a better understanding

of.the issues involved..

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L The inspection of November 1-15,.1989, examined the activities of management, the

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k operators, and the engineers involved in troubleshooting the recirculation flow

control system malfunctions experienced on January 17 and 18, 1989.- The inspection L

also addressed GSU's management direction and oversight at the time of these

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events and its followup actions. As a result of-the substantial additional

I information GSU officials presented during the; enforcement conference, we have

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-co_ncluded that the.' concerns' identified in NRC Inspection Report 50-458/89-41

regarding the effectiveness of management's response to the malfunctioning flow L

control. system and NRC's -concerns about GSU's reactor safety consciousness were

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not well founded. However, we have concluded that certain of your activities

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qwere in vio'lation of NRC. requirements. Consequently you are required to

. respond to these violations, in writing, in accordance with the provisions of

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.Section 2.201 of the NRC's " Rules of Practice," Part 2, Title.10, Code of Federal Regulations. Your response should be based on the specifics contained

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in the Notice of Violation enclosed with this letter.

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, Although the violations cited do not indicate a significant regulatory concern,

we continue to question the practice of troubleshooting an operating system (such as the recirculation flow control system) which can have such a marked

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impact on the reactivity of the reactor, and can cause power changes such as those observed in the events of January 17 and 18,1989.

In addition to the x

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Gulf States Utilities.

-2-n . . response required by the Notice of Violation enclosed with this letter,.please include.in the response information regarding-the actions GSU has taken, or ' plans'to take, to minimize the risk of large reactivity additions being made

during maintenance or troubleshooting. activities, or GSU's position regarding- - the necessity of such actions.

, -In'accordance with Section 2.790 of the NRC's " Rules of Practice," Part 2, i ' Title 10,- Code of Federal ~ Regulations, a copy of this letter and its enclosure will be placed in the NRC Public Document Room.

The responses directed by this letter and the enclosed Notice-are not. subject to the clearance procedures of the Office of Management and Budget as required: -by the Paperwork Reduction Act of 1980, Pub. L. No. 96-511.

Should you have'any. questions concerning this matter, we will be pleased to.

~ discuss them with you.

Sincerely, Original Signed By: , H Samuel J. Collins r Samuel J. Collins, Director Division of Reactor Projects

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Enclosures:

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Meeting Summary w/ Attachments c.

Notice of Violation L. >

REGION IV-NRC Inspection Report: 50-458/89-41.

Operating License: NPF-47 Docket:- 50-458-Licensee:- Gulf States Utilities Company-(GSU) P.O. Box 220 St. Francisville. Louisiana 70775 Facility Name: RiverBendStation(R85) Inspection At: RBS, St. Francisville, Louisiana < Inspection Conducted: November 1-15, 1989 ' b Inspectors:- t ' d. E. mglarco, cater. Operational Programs section Date .- L l, . ii. y -. . ~~. .phh .s . s Jones, Res1;w.t Inspector ua'te ' i Approved: / ^> /

dynnB r. JauG Wp' De ty D1 recto? Da t'e ' [)1 vision of 8eac r Safety Insoection Summary Inspection conducted November 1-15. 1989 (Recort 50-458/89-41) Areas Inspected: Monroutine, unannounced inspection of the reactor recirculation flow contro system selfunctions of January 17 and 18.1989 and the management actions related to the direction and oversight of these even,ts, t l

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Resultut invoiv ng failure to control troubleshooting and repair activities failure to perform post-maintenance testing, failure to take appropriate , corrective actions regarding the malfunctions - evaluate adequately the malfunctions (Paragrap,h 2.).ano failure to review and Collectively, these potential violations raise serious concerns regarding the effectiveness of management's response to the malfunctioning flow control System, particularly reactivity changes that resulted in several power and flow osc Further, management apparently failed to recognise the significance of. the flow control malfunctions and the resulting uncontrolled reactivity and flow oscilla-tions.

Consequently, corrective actions and actions to prevent recurrence did not provide adequate assurance that a similar event would be handled in a more conservative manner.

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.. .. - - -.- - - - . ...--.-.-- --__- .._ - ~.; . ,. - 3., ', , OETAILS- - . m , 1.~ . Persons Contacted - ., J. - A. Bowlby, Shift Supervisor . J. Boyle. Shift Supervisor l.

• G. A. Bysftold. Supervisor, Control Systems

' J. E. Booker, Manager. Oversight

• J. W. Cook. Lead Environmental Analyst, Nuclear Licensi D. Dawson, Reactor Ope
• T. C. Crouse, Manager,ratorOutlity Assurance (0A)

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• $.Finnegan, Shift SupervisorJ. C. Deddens. Sen<

or Vice President, River Send Nuclear G

• L. A. England, Director, Nuclear Licensing roup A. O. Fredieu. Supervisor O C. A. Fu, Field Engineer,,8.perations K. J. Giadrosich. Supervisor E.

P. D. Graham, Executive AssistantCuality Engineering D. Hicks, Field Engineering. G. E.

M. Jones Training InstructorR. Jackson Coordinator, Nuclear , L ,

• 0. N.'lorfinge Supervisor.-Nuclear Licensing

, ' 1. M. Malik,-Supervis

• W.' H. Odell, Manager,or Operations OA Administration
• T. F.-Plunkett. P ent Manager i
• M. F. Sankovich, Manager. Engineering

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• R.G. West Assistant Plant Manager *J. P. Schippert. Assi

' se , Technical Services The inspectors also interviewed additional licensee personnel inspection period.

I uring the

• Denotes those persons that attended the exit interview conducted on November 15, 198 attended the exit interview. 9.E. J. Ford. NRC Senior Resident also 2.

t Reactor Recirculation Flow Control Valve instability ! ! with the "B" reactor recirculation flow control on January.17-18,1989.

Inspection Report 50-458/89-04)During the Maintenance Team Inspection (NR . curred !. September 18 through October 17, 198g, the ins perfonned during the period of Reports wed Condition the *8" recirculation FCV.,The inspector initiated an unresol nstability of (458/890401) as a result of this review.

ved item L this Unresolved Item is discussed in the following paragraphsThe L I t .

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_ _ _ _ _ _.. .. m E', 2; < a.:. Background - 'On January 16, 1989, the licensee synchronized the main generator onto the grid following replacement of a failed ground fault relay, y Reactor-power-escalation continued through January 17, 1989, to-approximately 84 percent. At 10:18 p.m., the "B" recirculation FCV A control room log entry made on January 17, 198g, at 10:1 . states that, "HPU for 'B' flow control valve tripped due to excessive servo error, Valve position 765. Restored HPU teroed servo error, , reset lockup.

Erratic cycling of servo er,ror was observed with valve motion attempting to follow signal.

HPU again tripped on servo error (motion inhibit). Valve position 745."

During-the first event, the "8" reactor recirculation loop flow increased by approximately 2 million pounds mass per hour (mlbm/hr) as indicated by the individual Recirculation Loop Flow Chart Recorder 851-R614 After restorin motioninhibit,the"B"recirculatjonloopflowdecreasedby1the "B" Mpu and res ' m1be/hr.

The "B" HPU remained shutdown with the "B" FCV in the "lockuo" condition.

However, a slow hydraulic fluid leakage past the "B" FCV actuator allowed the FCV to drift in the open-direction. This resulted in a slow reactivity addition to the reactor. During the next 2 hours, the reactor cociant flow through the "B" recirculation loop increased-from approximately 29 mlbm/hr to 34 mlbm/hr.

Because of the increased feedwater demand resulting from th . production at the higher reactor thermal power (app (e incre roximately.

92 percent), the reactor operator at the controls ATC)wasrequired to place the startup feedwater regulating valve into service. At the time. the third feedwater regulating valve had been tagged out-of-service and was not available. Later, to maintain total reactor coolant flow below the 100 percent core flow limit of-84.5 m1bm/hr.

the ATC operator decreased the "A" recirculation loop flow. This-placed the plant into a 2-hour Technical Specification Limiting Condition for Operation (Technical Specification 3.4.1.3) with the rectreulation loop flow mismatch greater than 5 percent with total core flow greater than 70 percent. The basis for the flow mismatch specification is to ensure compliance with the emergency core cooling system loss of coolant accident analysis design criteria for two recirculation loop operation.

On January 18. 1989, at 12:07 a.m.. the licensee began inserting control rods to reduce the control rod line to less than 80 percent.

This was perforined to ensure that if the recirculation pumps tripped, the subsequent flow coast down would be below the area on the power-to-flow map where thermal hydraulic instability had been experienced . '"""" ' ) .. .

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"( -3- at other' boiling-water reactors. '(Reference Information Notice 88-39: LaSalle Unit ! Loss of Recirculation Pumps with Power-OscillationEvent). This action was completed within approximately 3 hours.

At this time, the licensee initiated prompt Maintenance Work Order (MWO) RS6ft6 to troubleshoot the "B".FCV " lockup" and excessive positive and negative control demands. The MWO authorized the - performance of troubleshooting activities under the direction of the ' I system engineer. The system engineer subsequently directed the instrument and contro11 L!&C) technicians to-11ft the leads-from the "B" FCV linear variable differential transducer (LVOT),which provided - feedback to the "B" FCV controller on FCV position.

- At approximately 1:40 a.a. on January 18.-1989, the ATC operator was able to drive the "B" FCV in the close direction. This was accomplished by lifting the leads from the "B"- FCV LV07, which provided feedback to the "8 FCV controller on FCV position. A negative servo error ' was then input on the "B" FCV by the ATC operator. The "B" Hpu then started'and the valve motion inhibit reset. When the valve eached the desired position, the ATC operator tripped the Hpu to stop the valve motion. The "B" FCV was again operated in the close direction at approximately 4:00 a.m. on January 18. 1989, utilizing the method described above.

At 6:00 a.m. on January 18, 1989, the oncesing operations crew relieved the operations crew that had originally experienced the malfunction (RSS operations crews work 12-hour shifts). At approximately 8:20 a.m.. the' ATC operator attempted to close the "B" FCV by restarting the "B"'HPU and resetting the motion inhibit. The operator input a small' negative servo error as indicated by the controller. When the ATC operator reset the "Be FCV "1ockup", the "B" FCV ramped open from 84 to 97 percent. : Recirculation "B" loop flow changed between 30.5 and 35.8 alba /hr. The ATC operator stopped the "B" FCV movement by-locking up the FCV. Total core flow increased to 104 percent and the recirculation loop 5 percent flow mismatch limit was exceeded.

Total core flow remained above 104 percent for approximately 3.5 l I minutes before the ATC operator was able to close the "B" FCV to match the 'A' recirculation loop flow. Reactor thermal power increased from approximately 74 to 77 percent as indicated by the average power l range monitor (APRM) strip chart because of the above event. The licensee has since postulated that the input servo error may have actually been slightly positive, which caused the "B" FCV to ramp open.

At approximately 11:50 a.m. on January 18. 1989, the ATC operator was able to operate the "B" FCV in the close direction to match the "A" recirculation loop flow.

because of the "B" FCV drift that was experienced with the FCV inThiswasnecessarglockedup."

In each of the 666Ve cabes, total core #1= was allowed to drift to approximately 100 percent.

In each case, the licensee was relying on Wu malfunctienins

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control system to control reactivity and remain within the RBS Technical Specification limit for recirculation loop flow.

The "A" and "B" FCV were then operated in the close directica to reduce

total core flow to approximately.85 percent; As a result of the troubleshooting activities authorized by MWO R56226 the licensee concluded-that a control card in the "B" FCV control-circuit-had failed and that a solenoid valve in the "B" HPU was not operating properly. At approximately 2:30 p.m.

the licensee reduced - total core flow to 61 percent and reactor thermal power to 60 percent.

This action was'taken by the reactor operators to place the "B" recirculation loop into a condition where the "B" FCV wonid not drift while the "B" HPU was out-of-service for the servo valve and eontrol-card.taplacement. Another consideration regarding this - decision was the fact that a 10 percent recirculation loop flow mismatch is allowed with total core flow below 70 percent. The control card replacement was authorized by MWO R56226 and the solenoid valve-replacement was' authorized by MW0 R118514 - After completion of the above maintenance activities, at about 4:18 p.m., the "B" HPU was started. When the "B" FCV motion inhibit was reset, the "B" FCV inmediately began following the oscillating servo error. The amplitude of each FCV movement increased with each cycle unti1= the ATC operator shut.down the "B" HpU after 5 seconds.- The emergency resoonse information system (ERIS) data taken indicated .Y COtK6RHS neutron flux varied between 45 and 88 percent during the "B" FCV movement. Reactor-thermal power remained relatively steady, h t rve) ' 'indivilual reeirculation loon f' ow chart recorder indicated that the "B" HP. was mar",ed and the met < on inn 1D1t reset on at least three aeematona fo' ' aw< na the shave avant. Tne incivio si Mc1rculation , loon flow chart recorder indteated that sis 11er " h" FW movements occurri huu ER 5 data was nat archived for the s10seogenn "B" FCV movements. "he iconsee subsequently determined tist tie .inear velocity transmitter had failed (as an open circuit) in the drywell, and thus the "B" FCV control circuity was not receiving a FCV velocity feedbacksignal.

During this period, the licensee also determined that the "8 FCV was moving in-excess of the RBS Technical Specifica-tion limit of 11 percent per second of valve stroke (Technical Specification 4.4.1.1.1).

The licensee subsequently declared the "B" recirculation loop inoper6ble and entered single loop operation (SLO) to correct the failed control circuitry.

Prior to the licensee implementing SLO on January 18, 1989 licenses engineering personnel discussed with the NRC resident inspector the planned corrective maintenance actions for the "B" loop recirculation FCV. The inspect.or questioned the potential Impact of the proposed technical solutions. Various applicable electrical drawings and schematics were utilized during this process to verify that the proposed actions would have conservative results.

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_ _ _ _ _........ -. g.1 ' . g.- .c ' s, f" !*E.. ~, , wiring was open circuited for the "l' FCV. thus causi tRoperable.: The licensee prepared an unreviewed safety question-deteminatten (USGS) review-for the proposed action.which involved adjustments ~to the FCV contro11er.

The adjustments would have the effect of changing the control of the FCV from a velocity and positten ' controller to a position controller only.

Subseevent to these ~ discussions, the inspector discussed, with regional and NRR personnel, the details of the corrective actions, problems with the-"8' FCV, the licensee's planned-and-their intent to 90 to single loop operation.

In conjunction with entry _jnto SLO. the inspector reviewed the implemen-tation of Procedure 60P 9004. ' Single Loop Operation * and observed Surveillance Test Procedure $TP-050-3001 " Power Distribution Limi Verification."' ~ L Assessment of the Malfunctioning Flow-Control Vaive System b.

This section of the report assesses the licensee's actions that resulted in. or followed the events described in Section 2.a.-above.

' It aise identifies-the potential violations that were identified by t the inspectors.

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The licensee had esperienced periodic problems with the recircu-

14 tion FCVs dP< ftina durina the 2 vaars orier "a thana ovanen.

g Corrective act<ons to step the valves from dridting whi's

" locked up" were not effective until the FCV actuators were rebuilt during the last refueling outage. Based on.this past

experience, w%n the "88 HPU tripped to the maintenance mode on January 17. 1999, because of excessive FCV servo error, the ATC operator made-several attempts to restart the "B" HPU.

These attempts resulted in the FCV moving with the oscillating servo error, and ATC operator intervention was required to " lockup" the '8" PCV and te minate the '88 FCV movements.

• The WO that authorized the troubleshooting activities to be perfomed at:the direction of the system engineer'dtd not provide positive procedure 1 controls. The engineer subsequently directed the ISC techair, tant to lift the control leads from the
• 8* LV07. This resulted in the control systes for the "B" FCV sensing'the valve to be at 50 percent open.

With the leads lifted. the ATC operator was able to establish a negative-servo error and drive the FCV in the close direction.

The valve was then stopped by the ATC operator shutting down the HPU when the valve reached the desired position. The licensee's fat 1ure to- @ o aevido sositive n;=Aral controls for the troublannantine of tu n acr4Avel ava*= (which ' nvolvet l' fting leads from the contro' c' reutta) is a potential violation of Technical Specification 6.8.1.

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. ' On January 18, 1989 at approximately 8:20 a.m.. the ATC ocerator l apparently had not establish a sufficient negative servo error prior to restartin @ was reset. the "B"g the "8' HPU. When the FCV motion inhibit POV ramsad enenea from 85 to 97 percent and the Meu snuteown. Tiis caused the total rocirculation core view to exceed 104 careant rae acontar than 3 a' nutes until the "B" Pcv coule De driven in the c'osed direction as described above The licensee documented the above event in Condition . Report 89 0042.

This in another exnmole of insufficient ernea-dural ou'de'ines/d'reet' ans. which 's a potential violation of Techn<ca spectricat< on 6.8.1 that led to an operational event.

• Reelacement of the "B" FCV contro? circuit "Madtenn' card and

@ "B" HPU servo valon were authorized by MW0s R$6226 and RllB514, respectively. He' 4her maintenance activity had n saaeified functional /coarab' itv tant menmed nrior to o' acine the compo-nent back in serv' ce. Gain ad.1ustments to both the namitten and velociuv controllers appeared to nave Been made on January 18 n Ca.)

19p. "n accordance with field engineers direction, but the ' unreviewed safety question determination was not performed until January 21, 1989, when the nuclear steam supply system vendor recommended specific gain adjustments to make the controller operate in the proportional mode only.

This is another example of activities, which were naeveNaad without specifically amoroved procedural Guidanco/ddrect'ons anc constitutes a potential @ vio'st1on or Techn'ca' 5pecification 6.8.1.

The fact that the cain ad.instment were m aa without a safety eva'uation is also a potentia' violation od the requirement of 10 CFR 50.69.

• Following replacement of the control card and solenoid valve.

the operator started the '8" HpU. When the FCV motion inhibit was reset. the FCV began tracking the oscillating servo error signal. The FCV position modulated between 25 and 38 percent open. The neutron flux subsequently varied between 45 and 88 percent as indicated on the AptNs. The neutron flux oscilla-tions were a direct result of the FCV movements. The amplitude of the valve swin with each cycle. gs, while tracking the servo error increased The FCV cycled with a frequency of less than i Hs and the event was terisinated by the ATC operator after approximately 5 seconds. The "B" FCV was subsequently operated an additional three times for troubleshooting activities as part of MWO R56tt6.

In each case the '88 FCV attempted to resocad to the oscillating servo erro,r, and the flow charts indicated that flow esc 111ations similar to those in the initial event (at 8:?0 a.m.) were experienced. The initial event was documented by the licensee on condition Report 89-0043. The licensee's failure to have deta< 1ed cost maintenance test orocedures to @ test the flow contro' systes fo110 min 0 tne repairs and tne fact that tDe teatino was nerformed on an operatino 1000 led to ' .. .. - ._ i ,_ ,... --

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' the sobsequent newer and fism ane111ations.

The licensee's . ' @ (cgr} Acain'strative Procedure AD4-0028. " Maintenance Work Order."

Revision 10. paragraph 5.12.26 states " Ensure post-maintenance testing is performed and the required documentation is attached to the NWO.. Appropriate post-maintenance testing shall be specified for all components that have been reworked, repaired, replaced, or modified. Record test results in the Functional Text /0perability Area of the MWO.* The licensee's fatiues ta have documented neatentatac==== tantina of the caeut eme h @ control system with adjusted cain csntrols. is a octontial violation of this orocedure and Tec in' eal soecificat' on s.a.1 " On January 18. 1989, the licensee detemined that the "B" FCV movements documented in Condition Reports 89-0042 and 89-0043 exceeded the 11 percent ser second Technical Specification limit for the valve's evenant in both open and close directions.

The licensee subsequently decla nd the "8' recirculation loop inoperable and entered into single loop operation. This deternination uas made after eceoletion of Sho "B" FCV troubi _ t shoot"re that ' ed to the newer and flow esc' r atton event described in Centit'on Report 89-0043.

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Condition Report 89-0048 addresses the R85 Technical Specifica-tion requirement that the FCVs " lockup" on a loss of HpU pressure.

The operators had observed a 13 percent per hour of full stroke drift of the "8' FCV at the higher total core flow rates. The licensee cited the October 9.1981, loss of coolant accident (LOCA) that analysis with recirculation FCV closure (LRG-!!) in deterisining the FCV drift, with the valve ' locked up," was within the Technical Specification requirement. The LRG-!! analysis references the emergency core cooling system (ECCS) analysis presented in chapter 6.3 of the USAR. which' assumes the FCVs undergo a " lockup' in their present position on high drywell pressure following a LOCA. "he anelvsis also assumes @ that one FCV fails ta 'lockna" and c' ones an a rate of 11 percent __noe 2: M.

The FCV W amore results d n an Encreased neak fuel c'i led ne sm oerature MT oF e50F. "De increased PCT was coletinines to remain withtm @e limits of 10 CFR 50.46. Because the FCV drift problem had been in the conservate direction (open) and the drift rate magnitude was smell. the 11cannae conclu6 d the '88 FCV was within the R88 Technica' soecification =at for Fcy "lockne". Tm inspectors d-d not ennetr reente ' with tj r a concl asica. The FCV ha< an uncontrol ed drift of oniv 13 neemt ner wur. but this drit was oeso wed in the "lockun" mode won no valve moviment was expected.

a flow control " system was as1 function' na and the licensee c id not take a conservacive acerosen ' n their analysis.

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{ The licensee subsequently concluded that the linear velocity transducer had failed with an open circuit in the drywell.

l This - resulted in the complete loss of the velocity feedback signal to the control system.

During the second refueltog outage the Itcensee identified that flute from the FCV actuator had leaked onto the linear variable transducer (Lvi) ano causes i.he vwen circuit.

A modification was made to both FCVs to direct any hydraulic fluid leaks away from the LVTs and the LVOTs.

' The NRC staff is concerned that in addition to the potential @ violations, the licensee's clant and engineorino staff relied on

I the malfunet< onine a= flow eentssi syntai ".a maintain rectreu.

' lation 1000 " lows within the RB5 Techn' ca Mc1fication m1==atch limits.

Tne action resulted in uncontrolle0 reactivity chances.

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Management involvement Operations management up to the level of assistant plant manager for operations was aware of the flow control problem at the time of the Although the licensee did insert control rods and reduce the event.

, control rod line to less than 80 percent early in the teouence of

events it does not annear that ste1Maat arecaut< ons or autdance was aives to the comenters other than a tacit accrova' to continue their trou)lesnocting activities.

, The inspectors interviewed the shift supervisors and other members of the operating crews that were on shift during the course of these events. The operating 100 for the evening of January 17. 1989, indicates that the operat< ons supervisor was notified of the probles at about 10:30 P.M., which was snortly after the problem with the FCV was first observed. According to the shift supervisor that was on

watch at the time of the init< al probles on January 17. 1989. he was notified by the operations w_aarvisor to "4estart the olant" and reset sne Tevi1on inn 1 bit' for the rGV. The shift supervisor said that every time they tried to reset the " action inhibit" and tried to close the valve. it would begin to open insteed. He said that the engineer, who had been called in to troublesheet the problem lifted ond in the circuit to restrict the sotton of the valve in the open a direction.

An Mid0 (R56226) had been issued to troubleshoot the flow conteel circuit but the inspectors found no definitive procedural controls other than Procedure GMP-0042 (which is the procedure for controlling lifted leads) to cover these troubleshooting activities.

The inspectors asked the operators if they were concerned about what was happening with the plant. Two of the operators (one was a shift supervisor) said that they were concerned about the uncontrolled reactivity additions and had expressed their concerns to their management The managers said that their management was not happy with the situation, but they were satisfied with e6at was being done to h correct the probles. None of those interviewed sai'$ that thav had recossended to their r r r t e, hat tne plant be s iu' % or~that the raant De placee inta ainaia ' com ocoration until t4 problem was reso' ved.

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After the probles had been inittelly identsfled as beirt caused by a ' - defective solenoid and e eefective control card, the sciencie one tne Control 8 sed were repleses. Th.e licensee mduced power and retteevle.

l t*0m f10e 40 less then 40 perceiit to make the repairs. Upon completing the repeirs, the liseesse perfo med what was te mse as troubleshooting activities on 2e system. They did not tem these activittaa am g post *RBietenenee beeHine. ans na soestnc posteettetenense teattne , was 9. rW a: Tel' our ne the roe atement o' tMe care ans solenete.' I Tne "tregelesnectine" ectivit' es that were E677 ore 90 fc110mine the maintenenes resultes in i;;6 rev sne power steiflit'ans. which ' DccurTse on 7"** *anosta mamatama.

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Lessons LearW and Liaiive Lations The inspection findi indiested that the 'icentee d' d not unearneams evertta sf January LP ane 18, L989. As a result, h Me sienifinafee af Meir ca.as we actions were nat naaaaaet ata 40 the signiff tance of sne e e.. . The inspetterp esked the indivievels interviewed to etsauss the I lessons they earned from the events of sensory 17 are 14.1989.

i Most of the individuals interviewed sold that they could not think of - l any lessen learned from the events. A few of the operators did note 1941 as e reselt of the event 8. they had caos te knew rete sDous the roeireulation fios sentret syster. Only one of the individuals l interviewed eseressed sensern with weet had happened. He said that 111s concern involved the he had mentioned #1s consere to e manager.

ific presseural scritrois and technical specifications fact that for reestivity etsitions beesuse of conteel ros are presort drifts. He said that the thenges in retirculetion flow else induced l l reactivity thenges, but there were no prescribed eetioes to be taken for Ois mode of reessivity addition. We said that he could ret ur.darstaad whw the reairemiattae Flam er.aaees were not coverac. hv

staller T=GMeal 5eesifientier ane nn-W1 rastemments.

l i Several of the operators interviewed said that they hec experienced driftine w14h the PCV nriar tri the events of January 17 and 18.1989.

l ppparently une 'Itcensee's fat'6re to 1+:aara na the sientfiennae av the earlier areale .ir:eutar to Jete fa< 1ere to a< ve = nacirma ' ~ M.

attenties te tRe evette 09 Jmary The Independent Safety tagineering trous (!stt) was tested to anstyte the perferasese of the plant feliceing the initial conduet of SLO.

the plant antarse into Following D e event 8 ef January L7-14. 1989, SLO for the first time.

ISES evaluated de Skt opretions and the This oreluation was documentes in Operating events' leading to SLO.

The taperience Report (CER) 80 004 eat was issued on July it.1969.

inspectors stead the ineivioue's tatarvierce Pegardtng peir awareness of the resort, which enelyzed the events Get led to the SLO sad the success of the SLO. Most of the inoividuals interviewee were unaw , '

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R [% ' o ' ' of the 15(6 report, but said ' hat it may have been placed on their t required reading list and they just did not recall it. The IStG ! report addressed the flow oscillatibr problems and had a number of good conclusions and recomendations that should have been the subject ' of critical evaluation by the plant staff. At the exit interview, i the inspectors were provided with a :opy of the staff's response to ' @ some of the recoseendations of the report. The response, which was ' dated November 7,1989 (nearly four months after the report was issued), did not address all of tho report issues _. The recossendations that were addressed (four of the s< s) were oniv mar linany accontanla.

Recossendation 89-004 04, which urgot the use of SLQ to troubleshoot flow control problems and prevent tne oscillations of January 1989 were not effectively addressed in tmo response. This does not reflect , I a strono safety concern on the cart of clann menacement for a oroeles that has such an effect on olant scwor leve's.

The inspectors also asked the individuals interviewed to describe any training that they had received concerning the events of January @ 1989. The insoectors found that as trainino had beer orovided to the " , coeratino crews recardi ta thana avants. The assistant plant manager ,I I said that he believed titt the two condition reports, which described the events, had been placed on the recuired reading lists for the operators. The operators did not recall reading the condition reports, and the inspectors were not successful in locating a copy of the reovired reading list that contained the subject condition , reports.

The training supervisor interviewed said that a training ' subject, such as the condition reports would normally not be placed into the operator training schedule unless it was recessended by the operations staff. The licensee should consider the need for ths L l trainino staff to take a more are-activo accroach to deteminina l 'essons lear e in

that need to be ' neluded in the tra' ning programs for a'1 p' ant disciplines.

The inspectors found that PA had performed a surveillance regarding single loop operations but they Dad not recognized the significance , of the events of January 1989 eyes though they had received the ISEG l ! report and the two condition reports that addressed these events.

Q Ouality assurance also needs ta be more sensitive to these types of events and taki a or5-active -- -ah ta a' artino inana.---- t reeardine potential oroF ens t gat have safets sienif< cance.

~ ' ~ The inspectors found that the facility review committee (FRC) had I reviewed Condition Report 89-0043 for resolution of the FCV system failures. However, the inspectors noted that the RC did not consider l the fact that the aaerotions staM was relying on the malfunction 1ne FCV system to remain w< nhin the 755 Technical 50ecifications. This condition was apparent ' a both Cas11tice Reports 89-0042 and 89-0043.

The RC. however, had not reviewed Condition Report 89-43, which documented the flow and power oscillations. According to a licensee representative they had not revised Condition Report 89-43 because the l l u ,

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, 'g :l b4 ^ event reported in it did not involve a Technical Specification limit - i being exceeded. The FRC's rev h responsibilities in-Technical Specification I,.s.3 reontre tant ener revier ircuns tnat arament a _ post tnilai naza' e to nue' aae La'atv. Ina evente, n" Januarv lemo _ Cor isle.ly annp een a Paaaa6&i lla threshald fer ' Rauen t iat th8uld he ~1ne' rees in ta' s eatmanew.

'his is a potentish vio' ation of the requ' roments e" Technical Specification 6.8.3.

The licensee needs to reevaluate the screening process employed to assure that this committee is' receiving the material (i.e. significant conditions reports) necessary to carry out its intended mission.. e.

Conthmions The weaknesses identified in these sections indicate a number of-potential violations, which individually may not constitute a signifi-cant safety concern.- but collectively raise serious questions regarding the safety-consciousnese of the operations and engineering ataffs and their managment. Further, the weaknesses identified above regarding the subsequent revieu and evaluation of this event raise concerns about the effectiveness of senagement contec1s and oversight ever the RBS corrective action program. The apparent lack of ressonsiveness ' of the opersticas staff to the !$t8 report conclusions and recoseenda-tions is of particular concern in this regard.- 3.

Exit interview An suit interview was conducted with licensee representatives identified in paragraph 1 on November ll. 1989. During this interview, the inspectors reviewed the scope and findings of the report. Other meetings between the inspectors and licenses annagement were held periodically during the inspection period to discuss identified concerns. The licensee did not identify as proprietary any information provided te. er reviewed by. the inspectors.

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