IR 05000293/1990021
| ML20062B633 | |
| Person / Time | |
|---|---|
| Site: | Pilgrim |
| Issue date: | 10/11/1990 |
| From: | Bettenhausen L, Conicella N, Conte R NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I) |
| To: | |
| Shared Package | |
| ML20062B630 | List: |
| References | |
| 50-293-90-21, NUDOCS 9010250380 | |
| Download: ML20062B633 (25) | |
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U.S. NUCLEAR REGULATORY COMMISSION
REGION I
Docket No.: 50-293 i-Report No.: 50-293/90-21 Licensee: Boston Edison Company n 800 Boylston Street l Boston, Massachusetts 02199 l' Facility: Pilgrim Nuclear Power Station Location: Plymouth, Massachusetts Dates: , September 5-7, 1990 Inspectors: A. E. Finkel, Senior Reactor Engineer W. T. Olsen, Resident Inspector Lead' Inspector: N 1- //'date
/ 70 N f/7Conicella, SenTor Operations Engineer .BWR Section Operations Branch, DR2 Reviewed by: . ,$ /d /d' 7d R.,7/ Conte, Chief, date BWFr Section, DRS Operations Branch, DRS Approved by: ,
_L ek H. Bettsnhausen, Chief _ [O////94 date Operations Branch, DRS
, ' Inspection Summary: See Executive Summary
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EXECUTIVE SUMMARY INSPECTION REPORT 50-293/90-21 On _ September 2,1990, at 10:33 p.m. , the reactor was manually shutdown from full power operation by the control room operators due to a feedwater level control component failure. The failure was a blown fuse in the~ feed regulating valve 1 (FRV) control power circuitry that caused the FRVs to lockup in their current , ,* position'and slowly drift open as air bled from the FRV pneumatic contro Reactor water level continued to slowly rise and the operators manually shutdown , the reactor when they concluded that they no longer had positive control of the FRV After the reactor was shutdown, the following operational complications
' -occurred: .(1) the reactor core isolation cooling system (RCIC) tripped three . separate times on manual. attempts at injection to the reactor; (2) the startup feedwater regulating valve developed an air leak that caused the valve to fail l .in the fully open position; (3) the high pressure coolant injection system (HPCI)-flow oscillated with the control system in automatic when the' system ,
was operated-in the. full flow test mode for reactor pressure control; (4) the opening contacts for the. Shutdown Cooling Suction Inboard Isolation Valve did not' seal-in when the operator attempted to'open this valve; and, (5) the shut-
- down cooling (SDC) system isolated on a Primary Containment Isolation' System- .(PCIS) Group 3 (100 psig reactor pressure isolation signal) when the system was .
initially-starte The component malfunctions with the HPCI'and the SDC systems' * either had little effect on the system's ability to operate.or' rendered the . system inoperable for.only a short period of time during the event. The other ; systems were inoperable.throughout the entire event. These component i malfunction:, complicated the shutdown process.- Shutdown cooling was successfully- , placed in service on September 3, 1990, at 5:33 The-inspection team determined that-the licensed operators responded appropriately to all. component malfunctions that occurred and maintained the ;
-reactor, in a safe condition at all times throughout the event. Both the licensee and the NRC inspection team found that several operating procedures ,
lacked adequate guidance for the operators and that flaws in one operaing-procedure were' directly responsible for causing the RCIC system to fai i The licensee ~and the NRC inspection-team found that poor maintenance practices I
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were directly involved in several of the component malfunctions. Additionally, based on_the maintenance in progress and observed by the NRC inspection team, ! licensee maintenance practices appear to be weak.' The licensee had noted )
, maintenance as an area that requires improvement in self-assessments conducted ' prior.to;this event. The licensee's corrective action program for addressing F maintenance weaknesses identified by their self-assessments did not appear to-be sufficiently aggressive.
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- The NRC inspection team concluded that the licensee's process for evaluating i ipost-trip: data was effective and appropriately focused. The licensee estab- {
J ' lished'a Multi-Disciplined Analysis' Team.(MDAT)'of 38 individuals whose mission > L Lwas to ensure that the event was understood, all component malfunctions were [ fully analyzed, and.that;the appropriate corrective actions were performe : Senior licensee. management gave the MDAT top priority and the appropriate I resources required for'the MDAT to properly accomplish its mi'ssion. Senior- ! k licenseefmanagement was aggressive in ensuring _ that the problems were -j Lunderstood. corrected and prevented ~from recurring. . At the time the NRC b team;left the: site, it appeared that the MDAT was successfully accomplishing i
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its1 goal.and the inspection team was_ confident the. licensee could effectivel analyze and correct the' problems that caused.and compilcated the event of j
: September' 2 '3,=1990. - i n 1
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ii-c TABLE 0F CONTENT i
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K , 1 ! 0 I n t 'r o d u c t i o n . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . - . -. . . . . . . . . . . . . . . . . . . . . . 5- 1
' Background';....................................................
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: Scope........................................................... 5
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' Team Composition.'.............................................-- 6'
;14.4: Summary of Major Findings / Conclusions......................... 6-
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< ;2.0 Esent' Description..:.........,...................................... 5-f f"' (
, -3.0 Licensid Operator Perfcrmance..................................... - 10 :
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. 3.1 Scope................... ..................................... 10
:3.2! Inspection. Details and Findings................................ 10-
'- ;3.3 Conclusions;............................................. ..... 12 .
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, 2 Maintenance....................................................... 13:
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L 4 . 1 S c o p e . . . . . . ' . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . .
' 4.2 "Inspecti on Detail s and Fi ndi ngs. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
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4 . 3 ' C o n c l u s i o n s . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -. . . . . . . . . . . 16-3 4 . 4 - R e c omme n da t i o n s . . ;. . . . -. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -.
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y>s @ ., y', 5.0 Multi-Discipline'd Analysis; Team................................... 16 y2 ..
'; ; 5 . 1. S c o p e . . s . . : . . = . . . . . :. . . . - . . .. . . . . . . . . . . . . . . . . . . . , . . . . . . . . . . . . . . . . . . . 16 .
5.2TInspection Details and Findings;...........................;... 1 b
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523 RootLCause? Analysis.._.........i............................,.. 17,
. 5 . 4 . C o n c l u s i o n s i . . . . . . . . . . . . - . , . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . .
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19c v b , , , , 56'.0 ManagementLMeetings.......................-........................... . 20:
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m; o [ ATTACHMENTS s
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L, < .' Attachment 11:. Chronology of Events-
. 3 Attachment3 1Ii Persons: Contacted a
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DETAILS 1.0 ' Introduction-
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l' . - 1.'1 Background
'On' September.2, 1990, at 10:33 p.m., the operators manually shutdown the - ' , reactor.from a full power condition due to a failure of the feed regulating valve-(FRV) control system. Af ter the reactor was shutdown,. additional r component malfunctions occurred in the reactor core isolation cooling T' (RCIC) system, the startup fetd regulating valve, the high pressure coolant injection (HPCI) system and the; shutdown cooling (SDC) syste The malfunctions in RCIC, the startup feedwater regulating valve, and the FRVs rendered these components completely inoperable throughout the even The malfunctions in the_HPCI and SDC systems rendered these systems inoperable for a short period of time but both the HPCI and SDC systems were eventually _able to perform their functions satisfactorily. These '
component malfunctions complicated the-shutdown process. Additionally, during the RCIC trip', the discharge check valve did not properly t seat and the RCIC suction piping experienced a pressure pulse. This
, _ pressure pulse'was discovered during the licensee's self-assessment i
several days after the event occurred. Inspection of the RCIC suction piping pressure pulse was.beyond the scope of the special inspection and
,, will not be discussed in this repor This event will be discussed in r Inspection Report 50-293/90-20. The plant was eventually stabilized with SDC in service.on September 3, 1990 at 5:33 A Special Inspection Team was formed on September 4, 1990 and was at the -
site:on September 5, 1990 to review the number of component malfunctions that complicated the manual shutdown of the reactor. The team concluded .; its inspection.on September 7, 199 ; a 1.2 SCOPE The scope'of the special inspection was: (1)-evaluate the performance of Lthe licensed operators during the event; (2) evaluate the performar.ce of the licensee's, Multi-Disciplined Analysis Team (MDAT) which was established
'to perform the post-trip review and develop corrective actions; and, (3) evaluate the facility's maintenance practices to determine if they1 contributed to the component malfunctions. In essence, the _ primar purpose of this inspection was to provide an expeditious review to ensure that the licensee could effectively address this event-to-determine root
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7 causes and develop appropriate corrective actions prior to restarting the I _ pl a n t'.
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To' accomplish its mission,. the team-used the guidance ~ of NRC Inspection- t
. Manual Chapter 9370 In addition, the team conducted po sonnel interviews,- '
procedures'and records review, and actual observation of-maintenance in--
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progres c ,
-1.3 14am' Composition I t-The team was' composed of three Region I personne Two were from thei j ; .
Division of Reactor Safety and had expertise in the areas of plant ., j operations'and plant maintenance; The third individual was tM facility's
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i NRC' resident inspector, '
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1,4 Summary df Major Findings / Conclusions Operations
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- T.he licensed operators responded appropriately to all the component-malfunctions that occurredi '
- The. operating procedure for reactor water level control malfunctions does not provide adequate guidance for rising. reactor water level
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. situations, m The!RCIC system operating-procedure was improperly validated-(used the. .
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simulator) and- thisidirectly resulted in the system failing ~when required; *
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-1The RCIC: system' operating, procedure does not provide an adequate-explanation'of:the proper operation-of. the mechanical overspeed trip' ,
mechanism,
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- The RCIC system operating procedure does not provide guidance fo j
'qa ;systemsstartup in the' full flow test mode and for swapover to and from '(
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vessel-injection and. full flow test mode :
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TheLHPCI system operating procedure does not provide adequate guidance + on.how the: system controller.is-to be operate "' 3,
'5 Maintenance d E - Even'though the inspection team directly observed and was made aware '
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of ~several examples of Lpoor maintenance practices, this event was not' l initiated by poorf maintenance. This. event wasfinitiated by' equipment- 1 , "
? failure. However,ipoor maintenance manifested;by-equipment failures i . complicated the. mitigation of:the even ,
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jU~< , The' licensee. informed the inspection' team that they had performed two Edifferent self-assessments of their maintenance practices and .both
"self-assessnents- have determined that maintenance problems existed 'and
+ :needed to.be addressed, The licensee psrformed these self-assessments prior to the-event, .In light o' the problems manifested, the proposed
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: improvements should be accelera.e '
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The FRVs had 'packis that~ was not' in accordance with the: vendor's manual,
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.(The licensee later reported that the packing used was authorized) s
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. The' packing leak on the 'B' FRV was repa' ired with sealing ~ compound twice . prior to the. event. The sealing-compound injections were not done in- .
accordance with the_ facility's maintenance procedure ' II - An effective inspection of the-electrical component:, and junction boxes exposed to the steam environment caused by the 'B' FRV packing leak was
, not performed. The junction boxes had indications that they had been.
' rusted for some time prior to the even ' ' - The NRC-observed workers removing the packing'from theB' FRV under- ;
inadequate lighting conditions. ' Additionally, the maintenance supervisor responsible for the.'B' FRV packing removal was not directly supervising r' the workers._ This: packing removal was more complicated than normal since-s the valve had been injected with sealing compound twice and-required , ,
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a'dditional work' planning,and. supervisio i'
' - A maintenance request had been written to repair an air leak on the - startup, FRV just prior to the event. The problem had been evaluated as d low priorit The air leak worsened and caused the valve to' fail during a the event. It appears the work prioritization process was not effective i at establishingithe appropriate priority in this cas a
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'. Improper dispo, .ioning'of at least two work requests written for ;the 'RCIC overspeed trip mechanism prior. to the event: indicates poor t ' maintenance or troubleshooting practice ~l
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, - The RCIC overspeed trip'v.appet did not move freely due to fouling- 4 apparently caused by a liquid' gasket substance that had been- used during ' .the last bearing cover reassembly.. Additionally .this substance had also ' . fouled the: RCIC- turbine oil, h -:The NRC directly observed the initial disassembly of the RCIC tappet assembl Up > to the . point of disassembly,' the- reason *for' the tappet binding was not known.: .There were no maintenance-supervisors or. plant'
engineers at the disassembly to record.as-found data or provide '7
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assistance to the workers if neede .
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Water / steam hammer events of the 'A' SDC system have occurred a~ number-
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of times in the past._ The' system walkdowns performed to inspect for [.
piping damage after:these events were not as comprehensive as they should.have t.een. A damaged' pipe hanger'was detected only.after this
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last event and there.was no data'from previous walkdowns of the' condition { of that pipe hange ~ _
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p I< Multi-Disciplined ~ Analysis Team U
- The MDAT_ investigations were thorough' and corrective actions were - 3 appropriate for all-items observed by the inspection tea _
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- The MDAT was.well staffed and had the full' support of licensee senior management _ to devote whatever resources were needed for the MDAT to -
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Recording of as-found information was wea However, this did not i seriously affect the MDAT's ability to accomplish its ta }
, . 0VERALL CONCLUSION [
The performance of the operators and the performance of the MDAT was found 1 to be_ acceptable, The team concluded that the licensee could determine i root causes and develop appropriate corrective actions. Most of the findings or questions that the inspection team had were already bein .. b addressed by the MDAT. However, it appears that maintenance practices ! i of the licensee may have been directly. responsible for a number'of the -
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component malfunctions that occurre Based on the' number of component ,
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malfunctions:that' occurred during this event, the'special inspection. team ' recommended to NRC. management that a management meeting be held'with the 4
. licensee. prior to plant-startup. The meeting was held September 12, 1990- U q - 'and startup was initiated September 18, 199 !
2.0 Event Description j Feedwater Regulating-Valves FV-642A(B)' > y OnLSeptember 2, 1990,.at 9i53 p.m., the reactor was operating at full- -o
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power when the " Reactor Water Hi/Lo Level" annunciator alarmed in th m i
: control room,' The~contro_1. room _ operators de ermined the actual reactor . water level as being 'HiFand water level:was continuing to_ slowly' ris ; ..This determination was-done by observing the water _ level indicators and " % recorders on panel C905 in"the control' room. The control' room: operators
..g 7 : attempted -to stabilize. reactor water . level by, cycling the reactor ,feedwater . y o
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pumpiminimum' flow valves _and by implementing.the applicable portions off * Ui;, . Procedure No. 2.4.49, " Loss of Normal Feed and Feedwater Control Valve-
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LMalfunction." The operators manuallyishutdown' the reactor at 10:33 '
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.-could not be operated from the control room. Throughout the reactor wate . "
Clevel1 . transient, the operators hadlno alarms or direct indications that M
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indicated the FRVs had malfunctioned other than: reactor water level not
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l 9 ( y' , Reactor Core Isolation' Cooling (RCIC)' I After the' operators manua'lly shutdown the reactor and they concluded tha p tr.e FRVs could not be'used to control reactor water level', the operators , attempted to: place the RCIC system in service. The RCIC system was started . in accordance with1 Procedure No. 2.2.22, " Reactor Co're Isolation Coolin '? System;(RCICS)." Upon starting the system, the turbine tripped due~.to an . actua'l overspeed condition. An operator.was dispatched to locally reset' l L the turbine mechanical overspeed mechanism for a restt.rt attemp E -
. -The RCIC' system was. started a second time in acco'rdance with' Procedure- l No. 2.2.22 and the. turbine. tripped once'again due to mechanical overspee " , ,
However,' actual turbine 1 speed did not reach the overspeed.setpoint. The 3-to sine tripped prematurely. The operator locally reset' the turbine !
:aechanical overspeed mechanism for a third restart attemp The-RCIC system was started a third time. However, the third start attempt involved starting the~ system in the full flow test mode and .then -realignin '
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for reactorivessel injection.. The system started and operated for over 1-
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minute butL then the system mechanical overspeed trip prematurelf -actuated J once'again. ' At this point the operators concluded that.RCIC was
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inoperable and did:not attempt' any further system start . Startup'Feedwater Regulating Valve FV-643
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'After the. reactor was.Snutdown, the operators isolated:the FRV flowpath '
(since the operators could not closejthe FRVs) and attempted to feed the
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reactor'usina the startup.feedwater regulating valve. :The operator '
-attempte'd:to.cluse the startup FRV, but feedwater. flow to the reactor
?. did not: respond as' expected. They concluded that.the startup FRV had
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' failed:to the fully open positio Since the valve wasc open and'coul ,
not.be closed,- the operators started and stopped main.feedwater pumps as n 'needed to maintain reactor water level, .
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[' High: Pressure Coolant: Injection.(HPCI) q
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a Duringi the shutdown, af ter: the main- steam isolation valves-(MSIV) had
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isolated due to high reactor water level, the HPCI system was manuall }
. initiated.several times., The first time it was initiated to raise reactor water' level' and the'second time it was initiated in the full flow test '
imode to control reactor: pressure. Both system starts were performed in
' , . *; Laccordance with Procedure-No. 2.2.21, " High Pressure Coolant-Injection 4 *, : System (HPCI)."= .- , L
A!' . .During the 'first HPCI start, thefsystem tripped due to turbine overspeed, l
* s automaticallyfreset itself; and . operated normally_~until the operator - ? manually secured the Tystem when it-was no longer needed to provide-water i f ' '
Lto:the reactor. ~0ther-than the momentary overspeed condition during the start seque'nce,.the' system operated as expecte ' 5' in'
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^ .HPCI"wasistarted the second time ~1n the full flow test mode to control-
@ , , ireactor: pressure. Once again, the. system tripped due to a-momentary-R , overspeed during the turbine start sequence. 'The~ trip' automatically
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pA reset itself=and system operation continued as expected. Then, when [, the HPCI' turbine was at:approximately'2600 rpm, flow began oscillatin The' operator switched the: flow controller from the automatic-toimanual-
. mode' and the 'oscilletions stopped. HPCI was operated successfully focL 3 w .spproximately 3 hours with the controller in macJai mode. The system was secured when no' longer needed to provide reactor pressure control, n c-ShutdownCooling(SDC} } >
On September 3,'1990,'at 11:15 a.m., with reactor pressure at 12 psig,-
, . the operators attempted to- open the-Shutdown Cooling Inboard Suction Valve 'MO-1001-50. When the handswitch was'taken to the OPEN position, the valve- 'did notLstroke fully'open. Upon troubleshooting by maintenance personnel',
it was discovered that the -seal-in circuit for the valve had failed =to operate. At 2:11 p.m., MO-1001-50 was opened by holding the handswitch: d in the OPEN position until.the valve stroked' fully ope '
.. a At 2:50'p.m;,Lthe 'A' residual heat. removal-(RHR) pump was started:to-
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J establish shutdown cooling. -Within 10 seconds of the pump. start'a SDC ;
, system isolation. occurred. The isolation was .a PrWry Containment . '
Isolation -System (PCIS) Group 3 isolation which wa. o.tivated when a high 1
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i, reactor pressure (100 psig) signal was sensed. The operators-susp'ected that the-isolation was due to a water hammer event since the reactor:was j
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depressurized, prior to.sta'rting the 'A' RHR< pump. A., inspection of the-
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RHR piping was performed to check- for any signs' ef < damage after the A suspected water hammer event. No damage was: detected. At 5:33 p.m., , the 'ASRHR pump,was started-and SDC was established, j
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q 13.0L Operations
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3.1-Scope a
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% ' The purpose of this portion of the special inspection was to evaluate the y sequence of eie ts that occurred and' determine.if the licensed operators' ,, performed-in. accordance with. approved procedure .2 Inspection Detailsiand Findings i The inspection team developed a chronology of events by reviewing control yk"i "
-room logs, interviewing . control room operators, reviewing Emergency .and -
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' , , Plant.Information Computer (EPIC) graphs and reviewing the'MDAT's draft-pf notes. The inspection team then analyzed the actions taken-by the Q.; operators.for each of.the-component malfunctions that occurred. This '
'gW analysis involved comparing thel actions taken by the ' licensed operators-
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against the actions delineated in the appropriate operating procedure :
.Each: of 'the component. malfunctions have been addressed earlier in '
section .1 T 1 1
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' 'Feedwater Regulating Valves f p ~
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The' operators actions for the lock-up _ of the feedwater regulating valves were compared;to-the required actions of Procedure No. 2.4l.49 (Loss o . Norm.11 Feed and Feedwater Control Valve Malfunction).- 'The operators took
. actions consistent with sections 4.2.1 and 4.2.2'of Procedure No. 2.4.4 ',
One action taken by the: operators that is not addressed in Procedure N j'
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2.4'.49 was that the ' operators cycled reactor feedwater pump (RFP) minimum
. flow' valves tot control reactor water level while implementing the -
procedural. troubleshooting steps of Procedure.No. 2.4.49. None of !
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the~ actions taken by the operators induced or. complicated the even , The operators manually scrammed the reactor once they had. exhausted '
< -the procedural steps to regain control of the FRVs'. The operators j significantly ' reduced:the transient that would have: occurred if they had; "
taken--no operator -action and allowed the reactor to automatically. scram "i from' a high level main turbine tri The inspection; team noted that Procedure No. 2.4.49 (Loss of Normal Feed y and Feedwater Control Valve Malfunction) does not provide adequate guidance- for; failure'of;both the:FRVs and the rising reactor water: level situations, t Reactor Core Isolation-Cooling " The operato'r actions;for the operation of'the'RCIC system were compared -
:to:the required actions -' 3rocedure No. 2.2.22 (Reactor Core Isolation- j ' Cooling System). The oh ors'took actions consistent with section l - for m.anual operation (for injection). This'.p'rocedural guideline was - fol' lowed > for the' first and second RCIC start attempts. The thi.rd RCIC'
start;was done by starting.RCIC,in the full flowitest mode'. ~This method
, of operating RCIC tis detailed in Procedure .No. 8. 5.5.1- (RCIC Pump -
Operability < Flow Rate and Valve Test). The RCIC turbine tripped:on all ' y' three. start. attempts. Additionally, all-the' turbine trips weretreset.in accordance' with the guidance; of section 7.3.2 (Operator Actions Followin a: Turbine Trip). None of the actions taken by the operators with regard "
" ,to.'the operation.of'RCIC induced or complicated the even ;The inspection team noted several procedural inadequacies with Procedure N .2.22 (Reactor Core Isolation Cooling). Section 7.4'(Manual 10peration for Injection), was. validated using the plant referencedf . simulator. Due to fidelity differences between the plant and the i } simulator, the procedure was inaccurate and was directly' responsible'fo "
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' ' inducing the initial. mechanical overspeed trip. Section 7.3.2 (Operator j hy' ' : Actions Following a Turbine Trip) does not provide adequate-guidance ' 'l regarding the proper! operation lof the-overspeed trip mechanism. I appears that'a' lack'of-understanding of the proper operation of the trip Lsystem may havelhad a'part in not detecting the. faulty' trip system prior > , fto thistevent, Finally, Procedure No. 2.2.22 (Reactor Core Isolation <
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gCooling) does not contain guidance within the body of the procedure for vstarting RCIC in the full flow test' mode and for swapover to and from the!
? vessel' injection and' full-flow test mode '
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@" Procedure 2.4.49 (Loss of Normal Feed and Feedwater Control Malfunction); discusses failure of:the Startup Regulating Valve in section 4. '
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This procedure is written with the assumption that.the valve fails closed.- For this event,-the valve failed open; thorefore, there was n '
' . appropriate procedural guidance for the operators to-follow. However, , Jusing the guidelines of E0P-1,-:the operators were able to control reactor p R water level. - Additionally the cycling of RFPs:as needed to maintain -
g ' reactor water level was verified not to exceed the, pump. start criteria of ! limitation 6.2.2 of Procedure No. 2.2.96 (Condensate and Feedwater System).
' t _ None of. the actions taken by the operators with regard to the operation of '
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n the startup feedwater regulating valve induced or complicated the even . The inspection team noted that Procedure No. 2.4.49 (Loss of Normal Feed . N and Feedwater Control Valve Malfunction) does not provide any guidance for failing open of the startup FRV that causes rising reactor water level situation High Pressure Coolant Injectio A
'n The operators' action.s for-the operation of the HPCI system.was compared
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.l to the required actions of Procedure No. 2.2.21'(High Pressure Coolant'
W Injection System). The operators took actions consistent with section ,
' .of Procedure?N .2 ?! for manual operation for both the injection and }
full flow test modes:.of' operation. - None of the actions taken by the 7 operators with. regard to the operation of the HPCI system induced or complicated the event. The operator action of placing the flow - controller.in' manual when flow oscillations developed was prudent and
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resultedgin mitigating the oscillation The inspectic:. team noted that Procedure No.3 2.2.21 (High Pressure Coolant ; Injectio'n) rystem operating procedure does not provide adequate guidance r
$ on acceptable bands-of operation for the automatic flow controlle r ..
' Shutdown Cooling j t -
LThe operators' actions for the operation of-the SDC system was compared - di
, @ toithe-required actions of Procedure No. 2.2.19 (Residua? Heat Removal).
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-The operators took actions consistent with . Attachment 7 of Procedure N *
E- 2.2.19 for placing ,RHR shutdown cooling inservice. None of the : actions ,, i :taken.by the operators with regard to the operation of the SDC system
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Linduced or complicated the failure.of the MO-1001-50 valve to Linitially-
!lll:- .,- [ - 1 , , 'open or:the spurious Group 3 PCIS isolation:of'the 'A' RHR loop of SD g L:u? ~3.3 ' Concl usi ons~ - Licensed operators performed appropriately.for all the component 1 *
malfunctions that occurred. This -event was neither inauced or
[r complicated.by operator acti ,
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'I s . A procedural:1nadeq0acy was directly responsible for inducing the .first . j RCIC-mechanical.overspeed' trip. Other' procedural inadequacies were noted butthey did not have a . serious impact on the operator's ability' to '
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mitigate the' event.
W', '4.0 Maintenance l
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'4.1 Scope- ?
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+ The purpose of this portion of-the special inspection was to evaluate 3
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m the facility's maintenance practices to determine if there were earlier indications-of the component malfunctions. The licensee's maintenance- i
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", practices were evaluated by.~ observing maintenance in progress in the plant; j 4-and-performing a brief review of facility identified maintenance problem '
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< 4.2 Inspection Details and Findings NRC Observations of Maintenance in Progress Th'e inspection' team witnessed the disassembly of the.RCIC turbine overspeed trip mechanism ~ The disassembly was performed by,two mechanics with-
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a direction-being provided by the RCIC turbine vendor. There were no licensee supervisory lor engineering personnel witnessing the disassembl During the-RCIC overspeed trip mechanism disassembly, it was discovered
. 1 that a foreign material had fouled the overspeed-tappet assembly, causing- '! ' the' assembly.,to operate sluggishly. The: inspection: team noted that during - , .this disassembly, the licensee appeared.to lack' control. The mechanic performing the disassembly of the overspeed trip mechanism did not'have j-any written instructions.to. follow. They were receiving. verbal instruction- ' .from the; vendor. The as-found conditions.of the various components of the disassembly were not recorded. The foreign. material that was scraped from 1 the: tappet assembly was not retained for evaluation. Finally,: the method-of cleaning the-tappet assembly was not specified. LThe inspection team ; ,; , discussed with.the~ licensee the general lack of: direction and documentation <
y that the mechanics displayed during the' disassembl i The inspection teamf also; witnessed the packing removal from the;'B' FR ' TheLpacking. removal was; performed by two mechanics..'As with the;RCIC
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overspeed trip mechanism ~ disassembly, there were-noLlicensee supervisory
.*L ' :or engineering-personnel witnessing the packing removal. A major concer t *
of:the inspection team was inadequate-1.ighting in the vicinity.of the FRVs lf' , so that' the mechanics had to'use a flashlightito see the packing. The i-lackLof. proper lighting indicated a weakness in the job planning and a
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M 0 @ , ' weakness inLthe work; supervision which allowed the-two mechanics to
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Jc'ommence the work.under these conditions. The: inspection. team discussed
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, 9; + thisfobservatio'n with the licensee and. explained the concern over improper #
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. -In addition to the. work actually observed:by the inspection team,_a numbar of-maintenance studies and. records were provided by the licensee. The: .following information.was obtained from the-licensee's self-assessment- of:
the event and was verLified by the. inspection team.' -Each of the. component-
* ' malfunctions have -been addressed separately. Additionally, the licensee informed the inspection team that they_had performed two different
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self-assessments of their maintenance practices. ' Both self-assessments have determined that maintenance is a weak area that needs to be further . addressed. 'One self-assessment, an organizational assessment review (0AR), started in January 1950 and is scheduled for completion-in October 199 > This OAR' addresses work control practices. The-other self-assessment
;,' : started July 31, 1990 and was completed on August 15, 1990. This later-
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. <self-assessment addressed.various maintenance issues'. ;
- . Feedwater Regulating-Valves-The !B' FRV (FV-642B) had -a packhg leak that was repaired on August 30
* .and 31,-1990 by injecting a seal'ng compound. The repairs were performed':
per MR 90-6-64. -The first injection did not stop the leak, so a
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.second injection had to be performed. The second injection was not
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performed in accordance with Maintenance Procedure 3.M.4-10 since the second injection did not have the docwented NED revie ! The' 'B' FRV; packing leak was first detected on August 12,.1990. The leak
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s was; monitored daily until it worsened to the point that immediate repairs were required on. August 30 and 31, 1990. Although the licensee was prompt to correct the packing leak once it had worsened, the licensee did not
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perform aLsystematic walkdown or. inspection of the area that was exposed-toithe steam leak to determine the impact of the leak-on nearby electrical _ -component Had a thorough inspection been performed, evidence of water -
, intrusionsinto the-junction box that supplied PS-656A may have.been i > detecte A .When.the packing was- removed from the 'B' FRV and evaluated, it was found that the' packing that had been in the valve did not reflect the packing it : material as identified in the vendor manual for the valve. Also, the : as-found packing configuration did not contain a lantern ring which is-
_ specified in design document' Drawing #B-13425 Altho' ugh a number of poor maintenance practices were associated with the
: FRVs ; the. insp;ction team did not attribute the~ failure of the 'FRVs as ' . being directly attributable to these: poor maintenance practice Startup'.Feedwater Regulating Valve ~
d On-August'26, 1990, an ai'r leak was discovered on the startup. feedwater:
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yy regulating valve t(FV-643). MR90-6-72 was generated to' document this i #i - H deficiency. At.the time the-air leak was categorized as minor, therefore,
. f the Maintenan'ce_ Request (MR) was planned to be worked during the next ' ' '
power reduction. Theileak worsened ~and eventually caused the valve to-fall in-the fully open position, e ' L, ay
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; y n- _15 .: . - , * The MR>to correct the air leak was generated in;accordance with the -. licensee.'s procedures;for prioritizing andl planning maigtenance. Although '
the' air fleak was prioritized in 'accordance with the licensee's procedures,
' .it appears-that'_the program for work prioritization and categorization was not' completely effective in this instanc The inspection team did not '
attribute;the failure of the..startup feedwater regulating valve to poor
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maintenance practice ' Reactor Core Isolation Cooling Improper operation of the RCIC turbine mechanical-overspeed mechanism had- ! t occurred on several occasio'ns' prior to this event. On August 23, 1990, the-turbine tripped twice during po:t maintenance surveillance _ testin N Failure and Malfunction Report 90-270 was generated and was dispositioned~ as satisfactory since the cause of the trips ~was attributed to improper
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resetting of the trip mechanism. On November 25, 1989, the turbine tripped- j
, during a surveillance test. Failure and Malfunction-Report 89-456 was-generated and 'was dispositioned as satisfactory since,the turbine was successfully operated.three times after the trip. The licensee failed to properly disposition the previcus malfunctions of the'RCIC turbine overspeed mechanis , ' During the: inspection of the overspeed mechanism, -it was discovered that d the ~ governor end bearing oil sump contained approximately 1/4 inch of j sludp . _ It'a'ppeared that the sludge resulted from the bearing. cap joint 1 sealer that was used .during previous disassembly and from the bearing wear 1 i' : products. -The sludge may:have also been_ responsible for the fouling of y the overspeed trip; tappet. assembly which is' housed in the: bearing ca Although*the initial failure of.the RCIC system during this event was .; 'directly caused.by an faulty operating-procedure, the subsequent failuresi -j b ; were'apparently ~ complicated .by improper preventive maintenance.of the; * ' ~ ' system. :The inspection team directly attributed the' improper operation -
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of -the RCIC overspeed trip ~ mechan' ism: system'during this ' event to improper' ' j
; dispositioninglof the previously. generated Failure-and. Malfunction .
nReports and' consequent. improper maintenance, a W LShutdown Cooling- ! q
% lThe' inspection; team did'not review any previous work records that related;
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;, Fto_ maintenance performed on the seal-in opening contacts for the MO-1001- .I w' 150 valv l e
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- ALlicensee walkdown of the RHR piping was performed af ter _the SDC system 1
' ' ! isolated due to the water hammer. event of-September 3, 1990. The walkdown l , was performed to' verify system integrity. During the walkdown, pipe ;
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jsupport H10-1-36SR was p; ulled slightly from the wall: and the base plate 7
, Lappeared to be deforinea. The licensee was not able to-determine if ths :
@t jsupportwas-damagedduringthisSDCisolation. Apparently, this pipe ! V ! support had not been: inspected since 1987 when a detailed inspection of
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4 the support was performed. -Isolations'of:the SDC system due to these: s . pressure transient events are a recurring problem at this facilit ~Similar isolations have occurred as recently as December 9,1989 'and-p
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Julyi3,'1990. Apparently, the system walkdowns performed after the e-1 isolations were not sufficient since there was no information on the *
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status of. pipe support H10-1-36SR prior to.this~most recent system
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walkdown.
, The inspection: team did not attribute the problems encountered with the - SDC system'during _this event to poor mainternance practice [
~4.3 Conclusion
- Although the inspection team directly observed and was made aware of-several . examples o.f poor maintenance practices, the component malfunction .
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that initiated this event.(FRV lockup due to blown fuse) cannot- be directly <
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-linked to. poor maintenanc .
This event was. caused by equipment'failere.' j 4.'4 Recommendation-
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- Improvements' planned by.the licensee'in the area of: plant maintenance,
'as determined by the licensee's self-assessments performed prior to this ,
event, should have accelerated. implementatio '.0 fulti-Disciplined Analysis Team 5.-1 Scope ,r
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Thecprimary . purpose of- this special . inspection-was-'to ensure that the: i licensee could adequately address this event from the' perspective of-
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determining the root causes and; implementing the appropriate corrective f actions. The licensee convened a multi-disciplined: analysis . team (MDAT)-
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to investigateLthi's~ event. The NRC inspectionEt'eam assessed the MDAT'sL Jability to perform analysi ,
'5.2 Inspection Details and Findings
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. Procedure No.. 1.3.37 (Post Trip Reviews) describes the requirements for: i
'MDAT review of certain events. The licensee immediately formed an MDAT
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l after'this event occurred. ~The MDAT was.. tasked with producing'a: root
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cause analysis and' recommending appropriate corrective actions. The MDAT: 1:
, - consisted of.a team leader and 37 individuals covering various discipline '. , , . .The 'MDAT 'was . operational during the day and-evening shif t L ,
The inspection team attendediseveral meetings that the MDAT team leader a i had with. licensee management. Additionally, the inspection. team witnessed'
'several members of the MDAT performing analysis of various records and '
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During the meetings with licensee management, it' was evident that the .
, licensee was interested in the MDAT performing as _ thorough an investigation as possible. The MDAT team leader was told by senior licensee management--
y that the MDAT was not' constrained by any schedule and that the MDAT had j
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R available whatever resources were needed to adequately perform their analysi , P ' The MDAT's investigation of the event was very thorough. .As an example, .! the HPCI overspeed trips, the RCIC suction piping pressure transient and T the damaged RHR-pipe support were discovered-after the. event _by the MDA a D The MDAT reviewed EPIC computer traces of all the systems.they were analyzing and investigated a11' systems that did not operate exactly as ' i ' per design. The MDAT generated a number of maintenance _ requests to investigate and correct problems detecte i
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The. inspection team noted that the MDAT displayed a weakness.in the recording of as-found data:for their root cause analysi Specific examples a're'the water found in the FRV electrical junction box and the foreign material ~found on the RCIC overspeed tappet assembly.- However,.
,the MDAT'.s root _cause~ analysis was thorough and appeared accurate and was j consistent'with Station Instruction SI-SG.1030 (Root Cause Analysis and :
Corrective Measures _ Evaluation).
The corrective. actions for the. problems analyzed by the MDAT.were also I comprehensive and appeared appropriate. The corrective actions recommended immediate repairs, design changes, component calibrations. end. procedure revisions' Additionally, the MDAT addressed licensee programmatic issues
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a that could prevent similar events from recurring. These included items such as a detailed inspection procedure for-equipment exposed to steam j : leaks and. gasket inspection and replacement criteri ~
;j , All the concerns: and questions that the NRC inspection team had_ regarding this. event were'aiready being addressed by the MDAT. . The_NRC inspectio ~ team had reasonable confidence that the licensee was able to adequately j address"the root cause of this event and!that appropriate corrective, j actions would be developed and effectively implemented. This conclusion 1 .was based on direct observation of'the MDA j 5.3 Root Cause Analysis' '
tThe following-is the' causal analysis for each of the component malfunction's -
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that occurred during the event.that have been-discussed in this repor ' The.rooticause analysis was dev' eloped by the'MDAT and'was reviewed by the
' ' inspection team. .The following was the staus of the MDAT's analysis as'of- i , ; September 7, 1990 when the inspection team left the site. After review of! i thel data and records provided,<.the' inspection team had no further questions ( 'ofEthe 11censee's analysis. Each component malfunction has been addressed 1 seperatel ,(
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Feedwater Regulating Valves FV-642A(BI
~0n August 12',- 1990, the 'B' feedwaur regulating valve-(FRV) was identified . l as -having a packing leak. :This was discovered.during a normal plant' -walkdown, . The leak was monitored routinely by. operations personnel. ?The c-leak worsened,to the= point that repairs were-required. -On August 30 and? * .c 3: 1990,la sealing compound was injected into the valve pccking- The_ . j-M , sealing conpound stopped the steam leak. The valve continued to be ; "
monitored to- ensure that.the leak did not recur. : A considerable amount of
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moisture was introduced in the vicinity.of the FRVs'and FRV control panels f rom the !B' FRV packing . leak.'
+ :The initiating cause of the September 2,1990 event was the failure of 'the -
FRV. position control circuitry. The control circuitry failed 'af ter t
. moisture from a steam leak that occurred from the 'B' FRV stem packing; entered an electrical junction box in the vicinity Of the FRVs,and con- >
densed in the casing for pressure switch PS-656A. -The moisture that .
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condensed in the pressure switch' casing grounded the pressure _ switch and'
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caused a 1/8 amp fuse in power supply 640-42 to blow and caused both FRVs totlock up. This'. power supply is for control _ power.to both the.FRVs and it-
'pso: supplies power for the control room indications for FRV-lock-u conditions. Therefore,:when the fuse blew, both'FRVs locked up and the control room operato'rs had no indi. cation of-the'FRV lock-up' conditio ;
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. Once the~FRVs lock'up, operating air is trapped inside the FRV actuators
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E and the valves will slowly drif t open as the air.. leaks ~ from the actuator I m and the opening spring causes the FRVs to.'ope For this event, it'was-later found that the-air. leakage from the 'A' FRV actuator.was-excessive,
'This caused the 'A' FRV to drift open. faster than it should.have. 'The , ' -result was a slowlyLi ncreasing reactor water. leve Reactor Core ~ Isolation-Cooling ' ~ ;m i 'The first overspeed trip was due'.to procedure 1No. 2.2.22 having'been- i - - '
Limproperly validated. Section 7.4 " Manual Operation -for Injection" :
> ' directed the operator to open Injection Valve MO-1301-49 when_RCIC pum R 3 -discharg'e pressure. equals reactor pressure. l However, due to the: .
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; configuration'of the automatic flow control flow sensor, the turbine was given an increase speed signal until the flow sensor _ senses the appropriate system flowe -With the. discharge valve closed,-there was'no flow'throug *
the. flow sensor, therefore, the turbine was given the: maximum increase l speed.signaliand thisLcaused the overspeed trip. This procedure was
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T, ' validated on-_the plant specific simulator and this overspeed trip did'not D
' ' occur. Apparently, there was a. difference in fidelity between the '
simulator'and'the actual plant such'that the valve operating' timing _ b s sequence was'much more critical in the plant'. e
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, ' -The second and' third loverspeed trips of the RCIC turbine were a result of ' . mechanical component' failures.of the overspeed trip' assembly. The licensee ; !? ' had' the turbine? vendor investigate the problem and the-- results ~were: .(1)
4' - mechanical 1 tolerances in the trip and-throttle linkage were excessive; (2)
:; light' rounding of the overspeed trip. tappet nut -latch surface; and (3)- foreign substance in the tappet guide of.the overspeed tappet and bell ;
assembly. These caused the RCIC system'to have an extremely sensitive , tripping system and caused difficulty in properly resetting trip conditions.
. Startup Feedwater Regulating Valve FV-643 The-startup FRV had drifted fully open due to an air leak on the diaphragm l of the pneumatic-booster relay. The startup FRV is.of a similar design to
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the main FRVs, therefore, as air pressure bled off the actuator, the valve
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drif ted open from spring pressur High Pressure Coolant Injection _ . 1 No. root cause analysis was available for review by the inspection team at- '
.the time of the inspectio Shutdown Cooling A failure of relay 16A-K29 contacts-5 and 6 was the'most probable cause I for thecseal-in circuit not functioning properly. However, the seal-in -i circuit was exercised several times after the event and the seal-in feature -
functioned appropriately each tim <
:The-isolation was not due to actual: reactor vessel pressure of1100 psig or greater,.'rather it was due.to a hydrodynamic event (water hammer) on the i; pump start . The actual reason was not clearly. understood by the licensee, y 'This;has-been a. recurring: problem with the 'A' loop'of SD , 5~.'4 Conclusions
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-- The'MDA7 investigations were thorough and corrective actions were .
appropriate'for all items observed by the inspection tea .j a ", . A
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- The MDAT was well staffed and had the full support of licensee. senior -
, . management to' devote whatever resources were needed for the MDAT-to 'l n '
.l effectively accomplish'its tas .
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- Recording of as-found information was wea '
However, this did not-
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, 62.0- Management Meetings During the course of this inspection, the: team conducted'several' meetings ,
with licensee management to discuss the status of the licensee's efforts
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to evaluate-the event (MDAT's efforts) and to discuss the status of. the inspection team's: findings. In. addition to the entrance. interview on:
?! -September 5, 1990,.there were discussions on several occasions-to support the needs of the inspection team. An exit-interview was' conducted on-Septembcr. 7,1990 torsummarize the major findings and. conclusions of. the .t inspection team. Personnel present at the' entrance ~and exit interviews i along with. personnel interviewed by the inspection. team are listed in
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cAttachment'll of this repor ) i t f k
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CHRONOLOGY OF EVENT The following. chronology'of events was developed by reviewing control-room logs; interviewing control room operators, reviewing EPIC graphs and -reviewing' J
:the MDAT's draft note ' > , DATE/ TIME EVENT DESCRIPTION = September 2,~1990' !
09:53 Both FRVs lock-up due to blown fuse in control circuit' power supply. Operators have no indication that FRVs are locked up. Both FRVs begin to slowly drift open with the 'A' FRV drifting-open at a faster ,(
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rate than 'B'. Operators have no indication that FRVs are drif ting ope ! t 09:55. Control room receives Hi/Lo water level- I annunciator. Operators verify that ' level
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is high and slowly rising. Operators entered Procedure No. 2.4.49, " Loss of .. Normal Feed and Feedwater Control Valve ]
, ' Malfunction" and attempt an FRV lock-up :
reset. High water level is +32 inche ! 09:58 p.m.- Operators switch FRV cortroller from-Master Auto to Master Manual. Reactor: e level continues to increase. FRV demand signals changed but'the valves did not
' respond.to the demand signal. Operators open the 'A' and 'B.' reactor feedwater g' pump'(RFP) minimum flow ' valve :59 p.m, Reactor water level is +39 inches and lowerin '
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110:00 Operators closed the 'B' RFP minimum flow valv a gm, ~ i
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10:01 p.m.- Reactor water level is +32 inches and stable, 4 , y e10:03 Plant' operator dispatched to check 'B' FRV t'. via camera. Operators closed the 'A' RFP >< minimum flow valve.
' ' 10:06 Reactor water level is +30 inches and risin ' 10:07' Operators switched.from 'B' channel-to 'A'
-channel level instrument for 3-element ,. contro / ' ^L J
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O , (; y 10:09:p. Plant. operator. reports that there is no
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t leaka'ge from'the 'BFR ,
.
T10:10 Operators opened the 'A' RFP minimum. flow.
1 valve and notice that reactor water level o is decreasing.
p 10:16 Reactor' water level is +36 inches and.
- increasing. Operato n opened the 'B' RFP
., minimum flow valve, a t 10:19 p.m.~ Operators closed the 'B' RFP minimum flow
' valv '
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[ 10:21 perators opened the 'B' RFP minimum flow valve, s
' 10:23 p.m?
Operators noticed reactor power was 2006 MWT. Operators. reduced recirculation flo :26 Reactor power was 1997 MWT. Operators i opened 'C' RFP minimum flow valv }
'10:33 ~ '
Operators reduced recirculation-pump speed n
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to 50 0 tripped theC'~RFP and manually
,,' scrammed the reactor. Operators tripped 'A'
, and 'B' RFPs after the scra :34 p.m,' Operators entered Emergency Operating Procedure
.E0P- ,,
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, , , Operators closed the feedwater downstream j li, block valves to isolate the open FRV j 10:44.pi . . .
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Operators started the 'A' RF ' l 40:50 ' Operators placed 'ARHR in suppression pool. coolin ' w, , c 10i57 ' '
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0perators -s_ tarted .RCIC for manual
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injection. 'It tripped due to mechanical-q' overspee , d ,.-
E10:59 p.m.' Plant' operators reset 'RCIC overspeed tri 'M s L 11 : 01 L 'p .m . : Operators cycled the 'B' - RF yU . ; 11:05 Operators started RCIC for manual
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: injection. It trippe I q
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f-# 11:1'2 p. ~ Operators started'R',1C in-full-flow test-mod It tripped while' swapping to . w
. injection' mode. :0perators started.'C' RFP.- . ' :14 ReactorLwater level is below +9. inches'and p b
rising. All appropriote automatic actions
~
,
"
occurred. ' Operators secured 'C'. RF Y' 11:.17 'MSIVs isolated and reactor water level'is l v +53 inche I J n' September 3, 1990 .
'
'
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00:01 Operators cycled the 'B' SRV to' control
;
-reactor pressur :02 Operators placed 'B' RHR in suppression i pool! coolin '
,
- .
00:03 : Operators entered E0P-3 due' to suppression J 5, , pool temperature of-80 deg m 00: N' Reactor water-level-is +9 inche :20 Operators started HPCI and injected for
.s,
'2 minutes then secured HPCI. -(times are -t
.. approximate) j
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-- 7 . 00:34l Operators entered E0P-3 due to high '
-suppression pool water-level of 132 !
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-inche !
,
,4 T 00:36' Operators cycled the 'C'-SRV to control m '
reactor pressure.
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, . . .
.
.
:00:40 to 02:00 Operators cycled the RFPs.as needed toD L1
, . , maintain reactor water level from +20 to
+40 inche j1
.a 00:43 aa .0perators. plat d HPCI in full flow tes j
.
k;o,g , for reactor pressure contro ,
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-
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'
01:02 a; Operators notified the NRC via ENS'of the Group 1 < P , g @l , l ESF actuatio , j
- 01:30 .
~0perators notified the.NRC via ENS for
,e plant updat j 02:01 a.; ' Operators-opened all MSIVs and continued- 1 cycling RFPs -to control reactor water
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" Operators secured HPCI,; m 03:4T c.mc t 03;54:a. Operators continued plant cooldown via the bypass valves.
-
. . ' , '
04:18 Operators notified the NRC via ENS for plant updat , '05i00 Reactor pressure is 100 psi (SDC high-pressure interlocks cleared)
~
05:00.to 11:15 Operators lowered torus water level and prepared 'A' RHR for'SDC.
Y 11:15 Operators attempted to open MD-1001-50 but
'
,
'j
,
- the valve-showed dual indication and'would '
not ope "
- :05i &C replaced the-blown fuse in power-supply G40-42 (Pnl C918) and. the FRV lock-up lights il'luminate ~
-- 02 : 11, p . m .' Operators opened the-MO-1001-50 valve by- g holding the handswitch'in the OPE '
.
position until the valve stroked fully d
- ope '02:50. l Operators started the ' A'_ RHR' pump -for SDC and_a Group:3 PCIS 100_psig' isolation:-
occurred, t
: 02:50 to; 05:20 p.m.; Operators inspected the RHR piping'for-integrity: af ter -the water -hammer isolation
'
m . ifrom'the 'A' RHR pump start.~ 04:41 p' . . Operators notified theLNRC via ENS of the Group:3 PCIS isolation.' -i 05i33- ' Operators started the 'A'=RHR pump'and SDC-
,
was establishe ,- y i
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~'q I -ATTACHMENT'Il i E $ s e PERSONS CONTACTED'
, ,J
'
, BECO f :K, :Highfill : Station Director- 1,2 )
?- , 'R. ' Anderson Plant Manager .
1 . !
% Kraf t,: Jr.! Plant Manager (a'cting). .
1,'2 ' ! F, E. LWagner' VP - Nuclear Engineering ?1, ) i ' 1 . G.; : Davi ~s ; VPL- Nuclear Administration 1,2 )
*
'R,L;Swanso Regu'latory Af fairs -Manager (acting) 1,2
'
c. ' , 'P. sHamilton. ComplianceJDivision Manager,
.
1,2~ j-F,;'Famulari. auality Assurance Department Manager 1,2 :
: R. : Fairbank' . Nuclear. Engineering Manager (acting) 1,2- !
?: lW.:Clancy
-
-
Technical Section' Manager (acting) 1
[l L'.- .- 011 v i c e .. Operation s;;Section ' Manager 1,2 s W Sti20s Maintenance Section Manager 1,2 .;
T; sullivan' ' Chief Operating Engineer
'
1 ! E .
- Carlson 'NSRA ' *
m D.' .Elli s; Senior _ Compliance Engineer . I' F, 'M. 'Brosee; Information. System Program Manager .2 l
"
i Smith- ' ;MDAT Team Leader - 2- u '
'
O. , Williams' NME 3
'
W. .Dicroce -NOS: 3 ,
: LR : Stiles ~ NOS 3 a
- .Cafarella'; NPRO 3 .
'
n
'
NRCi
- - - ,, .
E * f P ,
- ,
f N. fConi'cella DSenior Operations Engineer
,
1,2: " , A. Finkel; . , Senior Reactor: Engineer 1
. , L " .g . rJ. MacDonald nSenior Resident' Inspecto ' 1' ., , , @ gl 6W.-(0lsen Resident Inspector- 1,2- ; ,. .i .
ft
:
s g -j '1
% 3 Notes: >
. .
,
'r 11:: attended. entrance meeting on September.5,i1990 '
.j'/ , ;2J:?sttended exttomeeting.on September;7, 1990 P
y #,;; 2. :. interviewed by NRC inspection team J f d' , ,
, ' Fi r f
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