ML18087A871

Summary of 830418 Meeting W/Util Re Restart Status Rept Based on Reactor Scram Events

ML18087A871
Person / Time
Site:	Salem
Issue date:	04/18/1983
From:	Fischer D Office of Nuclear Reactor Regulation
To:	Office of Nuclear Reactor Regulation
References
NUDOCS 8304270319
Download: ML18087A871 (42)

Text

,.___.!_,_..... ":, t nocket Nos. 50-272

- and 50-311 UCENSF.E:

Public Service Electric and f1as Company Ft'.CILITIES:

Salem Units l and 2 StJB,JECT:

SU~1M.l\\RY OF MEETING HELD ON MARCH 14, 1983 RF.GARDING THE S.ll.tEM REST.l\\RT STJ1.T!JS REPORT A meeting was held with representatives of the licensee, Public Service Electric and Ras Company {Salem Nuclear Generating Station, Units 1 and 2),

and the staff on March 14, 1983 to inform the licensee that a Salem R~start Status Report had been provided the Commissioners for their March 15 briefing by the staff. fach of the issues delineated in the Status Report was discussed by the staff and our positions cl early sta.tedn*.~r:sdieaul enfor license~ responses to each of the issues was also discussed.

The licensee was also informed of a show cause order requestinq the licensee to provide additional information to the NRC.

Each of the *f.:1-veritems in the <order was discussed.

A date for impl ementatfon of the order was not set at the meeting.

F.nc.losure 1 is a list of attendees at the meeting. is a copy of the Status Report.

Enclosures:

.t\\s stated cc w/enclosures:

See next page

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.r- - 8304270319 830418 PDR ADOCK 05000272 S

PDR

n. C. Fischer, Project Manager Operating Reactors Branch #l Division of Licensing o * *

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NRG FORM 318 (10-80) NRCM 0240 OFFICIAL RECORD COPY USGPO: 1981..,.335-960

MEETING

SUMMARY

DISTRIBUTION OPERATING REACTORS BRANCH NO. l Docket/Central File NRC PDR L PDR NSIC ORB#1 Rdg J. Heltemes, AEOD B. Grimes. (Em erg ency Pre pa redness)

• S. Varga Project Manager DELO F.. L. Jordan, DEQA:IE J. M. Taylor, DRP;IE ACRS-10 NRC Participants cc:

Licensee w/short cc list

Docket Nos. 50-272 and 50-311 UNITED STATES NUCLEAR REGULATORY COMMISSION WA~HINGTON, D. C. 20555 Arri l 1R, l 9R1 LICENSEE:

Public Service Electric and Gas Company FACILITIES:

Salem Units l and 2

SUMMARY

OF MEETING HELD ON MARCH 14, 1983 REGARDING THE SALEM RESTART STATUS REPORT A meeting was held with representatives of the licensee, Public Service Electric and Gas Company (Salem Nuclear Generating Station, Units l and 2),

and the staff on March 14, 1983 to inform the licensee that a Salem Restart Status Report had been provided the Commissioners for their March 15 briefing by the staff. Each of the issues delineated in the Status Report was discussed by the staff and our positions clearly stated. A schedule*for licensee responses to each of the issues was also discussed.

The licensee was also informed of a show cause order requesting the licensee to provide additional information to the NRC.

Each of the five items in the order was discussed.

A date for implementation of the order was not set at the meeting.

Enclosure l is a list of attendees.at the meeting. Enclosure 2 is a copy of the Status Report.

Enclosures:

As stated cc w/enclosures:

See next page

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D. C. Fischer, Project Manager Operating Reactors Branch #1 Division of Licensing

Publi~ Service Electric and Gas Company cc:

Mark J. Wetterhahn, Esquire Conner and Wetterhahn Suite l 050 1747 Pennsylvania Avenue, NW Washington, D. C.

20006 Richard Fryling 9 Jr. 9 Esquire Assistant General Solicitor Public Servic~ Electric.and Gas Company Mail Code TSE - P.O. Box 570 Newark, New Jersey 07101 Gene Fisher, Bureau of Chief Bureau of Radiation Protection 380 Scotch Road Trenton, New Jersey 08628 Mr. R. L. Mittl, General Manager Nuclear Assurance and Regulation Public Service Electric and Gas Company Mail Code Tl6D - P-*. o. Box 570 Newark, New Jersey 07101 Mr. Henry J. Midura, Manager Salem Operations Public Service Electric and Ga~

Company P. O. Box E Hancocks Bridge, New Jerse.v 08038 Leif J. Norrholm, Resident Inspector Salem Nuclear Generating Station U. S. Nuclear Regulatory Commission Drawer I Hancocks Bridge, New Jersey 08038 Mr. Edwin Ac Liden, Manager=

Nuclear Licensing Public Service Electric and Gas Company Post Office Box 236 Hancocks Bridges New Jersey 08038 Regional Administrator - Region I U. S. Nuclear Regulatory Commission 631 Park Avenue King of Prussia, Pennsylvania 19406 Mr. Charles P. Johnson Assistant to Vice President - Nuclear Public Service Electric and Gas Company P.O. Box 570 80 Park Plaza - 15A Newark, New Jersey 07101

LIST OF ATTENDEES MIG;RCH 14, l 983 NAMF.

ORGANIZATION H. Denton NRC/NRR G. Lainas NRR/DL R. Starostecki Region I J. Scinto NRC/OELD J. Lieberman NRC/ES D. Ftscher NRR/ORB#l R. Eckert PSE&G E. Liden PSE&G R. Uderttz PSE&G H. Midura PSE&G J. Boettger PSE&G R. F'ryl tng PSE&G M. Wetterhahn PSE&G ENCLOSURE 1

Fi\\lCLOSURE 2 March 14, 1983 For:

From:

Purpose:

Discussion:

POLICY ISSUE (Information)

The Commissioners W111tam J. Dtrcks Executive Director for Operations SALEM RESTART To provide the Commi"sstoners with a report on the current status of the staff evaluation of the failure to automatically scram events of February 22 and 25, 1983 at the Salem Nuclear Generating Station and the staff action plan for authorizing restart of Units 1 anq 2.

• curing a briefing on March 2, 1983 concerning the Salem reactor trip system failure events, the Commissioners requested that the staff provide its plan of action to resolve the issues identified from the NRC evaluation of th~

Salem even~s.

Enclosed is the Salem Restart status report which identifies the tssues related to the recent Salem events and the short-and longetenn actions needed to resolve those issues.

For the short-term actions-, the staff has or intends to obtain specific commitments from the licensee to complete those actions and the staff will assure their satisfactory completion prior to permitting restart of either Salem unit.

For satisfactory resolution of the long-term acti9ns, the staff intends to develop with the licensee an acceptab1e schedule for completion of those actions, obtain necessary written commitments, and fo11ow up their completion on the agreed upon schedule.

Contact:

Gus Latnas X-27817 R. Starostecki FTS-488-1230

Th~ Commissioners

Enclosures:

In addition to the short-and long~term actions identified jn the report~ the staff has also concluded that a show cause order should be fssued to the licensee (see enclosure 2)o The staff be1teves that the particular circumstances at thts facility, as further detailed in the start 0 up report, justify requiring that these three separate but interrelated sets of actions be implemented by the licensee in a tjme1y fashion o Subject to satisfactory impl ementatfon of these actions, the staff has conc1uaed that the Salem facilities can be restarted and operated without undue risk to the health and safety of the public. Enforcement actions are under active consideratton by the staff and will be discussed separately with the Commission at a later date.

• -~

Willia

• Dircks Executive Director for Operations

1. Salem Restart Status Report

2. Oft Show Cause Order D.ISTRIBUTION:

Commissioners OGC OPE CIA SECY

)o

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L Summary II. Background n::L Issues Ac Equipment Issues SALEM RESTART STATUS REPORT

l.

Safety C1assification of Breakers 2o Identification of Cause of Failure

3.

Verification Testing

4.

Maintenance and Surveillance Procedures Bo Operator Procedures, Training, and Resoonse Issues L

Operating Procedure for Reactor Trips and Anticipated Tran-sients Without Scram (AlWS) lo Operator Training

3.

Operator Response C.

Management Issues

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Overall Management Capability and Performance

2.

Master Equipment List

3.

Procurement Procedures

4.

Work-Order Procedures

5.

Post-Trip ~evi ew.

6.

Timeliness of Event Notification

7.

Updating Vendor-Supplied Information

8.

Involvement of QA Personnel with Other Station Departments

9.

Post Maintenance Operability Testing IV.

Conclusions Appendix A Results of NRC Staff Evaluation of Events at Salem Nuclear Generating Station

• Appendix B Initial NRC Staff Review of Licensee 1s Maintenance Procedure and Preoperational Verification Program i

e-Salem Restart Status Report.

I.

Summary This report briefly describes the NRC and lic~nsee actions ta address and resolve equipment, operator procedures, training and responsej and management issues identified by the NRC evaluation of the two events at Unit l of the Salem Nuclear Generating Station that resulted in failure af the reactor to trip automatically upon a valid signal. The second event occurred ~n Febru-ary 259 1983 and led to the realization that a similar event had occurred on FebrYary 22, 1983.

Based on NRC evaluation, a number of potential contribu-tors tQ failure have been identified. Hgwever, our initial evaluation indi-cates that all of the* potential contributers to the fai1ure are age-related and that a new device should perform properly *.

An NRC task force has been established to conduct a separate longer range s~udy of the broader implications of the events.

NRC 1ong-term actions identified herein are applicable to Salem but may have generic implications.

The NRC task force will determine generic actions needed for other facilities.

For the Salem facility, longer term actions developed-by this task force may complement the long-term actions identifiecfnerein.

NRC short-term actions identified in* this report must be satisfac:tcri1y completed before plant startup~

II. Background On February 25, 1983 an event occurred at Unit l of the Salem Nuclear Generate ing Station when the reactor-trip circuit.breakers failed to automatically open following receipt af a valid trip signal from the Reactor Protection System (RPS).

The manual trip system was used to shut down the reactor.

Subsequently, it was concluded by the licensee that the failure to trip was caused by a malfunction of the undervoltage (UV) trip attachments in both reactoi-trip circuit breakers. These UV trip attachments translate the electrical signal from the RPS tc a mechanical action that opens the circuit bM!aker.

On February 26, 1983, an NRC team was onsite ta conduct initial followup and to collect preliminary information.

As a T"9su1t of HRC inquiries, the licensee determined that both reactor-trip circuit breakers had similarly failed to open upon receipt of a valid trip signal* on February 22, l983.

The failure to auto-matically trip on February 22 was net recognized by the licensee until the com-puter printout of the sequence of events was reexamined in.more detail on February 26.

Further evaluation of these events and the* circumstances leading up to them rev.ealed a number of issues that require resolution by the licensee and/or the NRC.

This report identifies those issues and the short-term actions proposed to resolve them prior to resumption of operation at Sale.in Unit l;i an.d

• Salem Unit Z is presently shut down for refueling and is not pr~sent1y scheduled to resume operation before Unit l.

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the ~ong-tarm actions that are needed following restart. The short-term actions required for Unit l will also be implemented on Unit 2 prior to restart of Unit z.

The licensee met with NRC staff on February 28, March S, and March 10, 1983 to present the results of initial evaluations related to the events.

Based-on licensee submittals of March l and March a, 1983 and on the findings of the HRC evaluation of the Salem events, issues were identified and categorized as equipment issues, operator procedure, training.and response issues, and management issues. They are discussed in detail in Section III of this report.

III. Issues A.

Eguioment Issues Three of the issues relata to the affected equipment, that is, the reactor-trip circuit breakers (Westinghouse DB-50 circuit breakers).

These issues are l) safety classification.of the circuit breakers, 2) identification of the cause of the failure, and 3} verification testing of the circuit breakers *

l. Safety Classification of Breakers During the_ initial NRC evaluation of the February 25 event, it was determined that maintenance was conducted on the-Sal.em_Unit l reactor-trip circuit breakers in January 1983, following a failure of.one rea~tcr-trip circuit breaker to trip upon receipt of an RPS signal at Salem Unit 2 on January 6, 1983.

The-work orders authorizing the January 1983 maintenance identified the maintenance as not safety related and not requiring quality assurance review.

As a result, it was not clear on February 26, 1983 what portion, if any, of the reactor-trip circuit breakers was cansideN!d safety related by the licen-see. The reactor-trip circuit breakers contain both a UV trip attachment and a shunt trip attachment, but only the UV trip attachment is operated by an automatic RPS trip signal.

Action/Evaluation This issue has been resolved. Section 7.2.l.l of the Salem Updated Final Safety Analysis Report (UFSAR), Revision O, indicates that the Reactor Trip System includes the reactor-trip circuit breakers and the UV trip attachment.

The Westinghouse Solid State Logic Protection System Description (~CAP-7488L) also defines the scope of the system as including the reactor-trip circuit breakers and the UV trip attachments.

The UV trip attachment and the reactor-trip circuit breaker are safety-related equipment in that they are essential features of the Reactor Trip System, which is necessary to prevent or mitigate the consequences of a design-basis event that could result in exceeding the offsite exposure guidelines set forth in 10 CFR _Part 100.

The shunt trip attachment of the reactor-trip circuit breakers in the Westinghouse design is not required by present NRC regulations to be safety grade and, although it is provided to perfonn the manual trip function, no credit is taken for this design feature in the safety analysis (a manual reactor trip also actuates the UV trip attachmeftt).

The licensee in a March l, 1983 letter to NRC concurred 5

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in this understanding.

Hence, the specific issue-with regard to the safety classification of the reactor-trip circuit breakers is considered resolved.

Other issues concerning the manner in which the reactor-trip-circuit breakers were treated from a procuremeflt and maintenance standpoint at Salem are -

addressed under Management issues (Se~tion III C).

The li~ensee has made a.

commitment to install new UV trip attachments on all four Unit l circuit.

breakers prior to restart and ta verify that the new circuit breakers have b~en pr.operly serviced and testedo Z.

Identification of Cause of Failure The licensee 1s initial determination of the cause of the failure of the reactor-trip circuit breakers (as documented in a March l, 1983 letter) was t~at there was binding and excessive friction of the vertical latch lever of the UV trip attachment due to a lack of proper lubrication. This conclusion was concurred in by Westinghouse representatives and was based on* visual i_nspec:tian of the UV trip attachment, in-place testing performed after the failures, and previous Westinghouse experiencea The NRC has conducted an initial determination of the cause of the failure based on inspection of the failed UV trip attachments and* interviews with cognizant maintenance personnel on how the devices were maintained.

The inspection indicates that there were possibly.multiple contributing causes of failure.

Possi.ble contributors are (l) dust and dirt; (2) lack of lucrica-tion; (3) wear; (4) mare frequent Qpera:tian-than intended by design; (5) cor-rosion from improper lubrication in January 1983; and (6) nicking of laU:h surfaces caused by.. vibra.tion from.repeated operation of the breaker.

The contributors appear to be cumulat-ive, with no one main cause.

The initial investigation alsa indicates that all of the potential contributors to the failure of the UV trip attachments are age related and that a new device would likely perform properly.

Many surfaces of the latch mechanism are worn and the additional friction tended to prevent proper operation.

Proper lubrica-tion throughout the life of the device might have prevented the wear that can be seen on the sample.

These initial findings indicate that the UV trip attachment failed from binding and excessive*friction.

However, in addition to the potentia1 contri~

butars cited above, there remains the possibility that other UV trip attachment or breaker problems may have caused the Salem failures... aecause of the importance ta safety of the reactor""trip circuit breakers and UV trip attachments, the NRC staff has* prepared a more structured approach to resolv-ing this issue. Therefore, a laboratory testing and examination program funded by NRC will attempt to determine the precise cause of failure.

Appendix A describes the initial NRC inspection effort and extent of addjtional examination and testing to be done by NRC.

NRC Action*~ Short Term HRC conducted an initial evaluation of the cause of the UV trip attachment f.ail-ures which included visual examination of the devices by qualified personnel and determining how the devices were maintained (See Appendix A for details).

Based on. this, we conclude that operatio"n with new devices, in conjunction '1tith preoperational testing and periodic surveillance, is acceptable.

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.e NRC Action - Lona Term NRC will conduct laboratory testing and examination of the failed attachments to determine the precise cause of failure, if possible.

We anticip*ate th.at this work will be complete within one montn and the results wi11 be avai}able for consideration by the generic task force.

3o Verification Testing On August 20, 1982, one reactor-trip circuit breaker on Unit 2 failed to operate during surveillance testing. A UV trip attachment*was reinsta1led on this ci~uit breaker after replacing the coil, the circuit breaker was rein-stalled, and subsequent post maintenance testing was performed to establish operability.

Similarly, on Janual""j 6, 1983, a reactor trip occurred at Salem Unit 2 due to a low-1ow steam generator level, but one reactor-trip cireuit breaker failed to openo The licensee concluded that the circuit breaker fail-ure was due to binding from dirt and corrosion in the UV trip attachment.

The UV trip attachment on the Unit 2 circuit breaker, as well as the UV trip attachment on a11"Unit l reactor-trip circuit breakers, was cleaned, lubricated and readjusted under supervision of a Westinghouse representative.

On Febru-ary 20, both breakers performed satisfactorily during reactor trip events.

Since the circuit breaken again failed on Februal""j 22 and 25, adequacy of the testing to ensure circuit b_reaker operability is an issue. Testing following rsactor-otrip circuit breaker ~aintenance.Q.!._initial installation should be sufficiently comprehensive to provide reasonable assurance that the circuit breaker will function as needed.

Licensee Action c Short T-erm The licensee has proposed a program to verify proper operation of the reactor-trip cirt":uit breakers prior to returning them to service. The program will involve preinstallation testing of UV trip attachments 25 times by the vendor.

After installation on the trip breakers, the UV trip attachment and trip breaker will be tested ten more timeso Once initial adjustments have been per-formed, any failure in the 25 cycle or 10 cycle tests wi11 constitute a failure of the trip assembly and investigation of the cause of failure and NRC notifi-cation will be required.

Following this testing, a time response test of the breaker actuated through the RPS will be performed.

The NRC staff considers this issue to be sufficiently resolved to permit restart of the plant. pending a commitment by the licensee to develop and implement a program comparable to that described below under Long Term.

Licensee Action c Long TeMl'i Although the licensee has not yet proposed a long-term program, the NRC staff has concluded that an extensive bench test of the reliability of a reactor-trip circuit breaker and UV and shunt trip attachments as an integrated unit is indicated.

The test would involve cycling (a total of 2000 cycles: 1000 trips by UV trip attachment and 1000 trips by shunt trip attachment*) under simulated environmental service conditions to determine if a properly main-tained circuit breaker and its attachment*s can operate for an extended number of cycles.

The purpose of this test will be to determi~e if there.are accu-mulated effects which will affect proper*breaker operation.

If these tests 7

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point to spe~1fic defi~iencie: !n ccmponents or in the integral assembly, further testing or design mod1f1cations may be indicated.

The testing would be* performed by the licensee or appropriate industry owners group or vendor.

We anticipate that this program could ba completed within six months.*

NRC Action - Short Term NRC wi11 verify satisfactory completion of the 1icansee's short-term preopera~

ti anal testing prngramo NRC Action - Lona Term HRC wi11 require the licensee to esta~lish a 1ong~term reliability test program for the reactor-trip circuit breakers and will assure ti1at the fo11ow-irig points are included:

l.

2.

3.

a sufficient number of cycles is included to provide statistically meaningful results.

the test exercises both UV and shunt trip attachments (not simultaneously),

as well as the cirt:uit breakers.

t..ie test is conducted under environmental conditions similar to those seen by the circuit breakers.

4.

sufficient delay t~me is included between cycles to'a11ow return to steady-state canditjons.

5.

test procedures and acceptance criteria which will give reasonable assur-ance of uncovering possible deficiencies in the integral breaker assembly

• and individual components.

4.

Maintenance and Surveillance Procedures During the review, it was determined that no specific ma i ntanance procedure

~isted at the Salem facility to conduct preventive or cor~ective maintenance on the reactor°""trip circuit breakers.

The maintenance conducted in January 1983 was not performed in accordance with the latest Westinghouse recommenda-*

tians, which were contained in Westinghouse Tet:hnical Bulletin NSD-74-l, as amende~ by technical data letter NSD-74-2.

Additionally, no program of preventive maintenance had been conducted on these circuit breakers since original installation.

With respect to surveillance testing; the licensee conducted a functional test of one of the two reactor-trip circuit breakers.every month, so each circuit breaker was tested once every two months.

The surveillance tests involved tripping a circuit breaker by use of the UV trip attachment.

The licensee also operated the circuit breakers weekly by exercising the shunt trip attach-ment. In view of the numbe*r of reactor-trip circuit breaker failures at Sal ei:n, it appears that the periodic surveillance testing was ineffective in detecting a

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e reactor-trip circuit breaker failures of the type experienced on February 22 and 2~, 1983.

The licensee has now developed a maintenance procedure and preoperational verification ~rogram. The NRC staff initial review of the procedures and pro-gram identified certain deficiencies (see Appendix B).

Licensee Action - Short Term The licansee has now developed a specific preventive maintenance procedure for use on the reactor-trip circuit breakers (including the UV trip attachment),

which is based on all applicable vendor maintenance reconunendations, appropri-ate quality assurance (QA) requirements, and post maintenance testing *.

The licensee has proposed monthly testing of the main reactor-trip circuit breakers by use of the UV trip attachment and weekly testing of the reactor-trip circuit breakers by use of the shunt trip attachment.

We do not agree with the we~kly testing interval of the shunt trip attachment, as further discussed in Appendix B, and will also require that the associated bypass breakers be tested prior ta plant restart and at each refueling outage.

Licensee Action - Long Term The NRC will *require that the licensee in~fporate results of a long-term verification testing of the reactor-trip circuit breaker into maintenance and surveillance programs.

This action should be completed within two months of ccmpletion of long-term testing.

NRC Action - Short Term The NRC staff has completed an initial review of the surveillance and mainte-nance program and its procedures.

Certain deficiencies have been identified (see Appendix B).

The licensee will be* required to complete action necessary*

to resolve the identified deficiencies prior to restart and to reduce the frequency of testing the shunt trip attachment unless compelling reasons to the contrary are developed.

NRC Action - Long Term NRC will evaluate the licensee's proposed lubrication requirements for the UV trip attachments (i.e., type of lubricant, frequency of lubrication, points of application, etc.).

NRC wi11 also assure that results of 1ong-term*verifica 9

-*-e tion tasting of the reactor-trip circuit breakers are adequately in~orporated into maintenance and surveillance programs ta detar-mine testing frequency, inspection requirements>> and lifetimes.

The evaluations wi11 be conducted with the assistance of the Frankiin Research Center (FRC) and the Brookhaven National Laboratory (BNL).

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B.

Ooeratinq Procedures. Ooerator Training. and Ooerator Resocnse Issues Based on examination of the cir"Cumstances associated with the events involving reactor-trip circuit breakers, certain issues nave been identified relative to procedures 9 training, and operator response.

They are

l.

Operating procedures for reactor trip and ATWS

2.

Operator training effectiveness relative.to the RPS and associated indicators

3.

Operator response These issues are discussed in the sections below.

l.,

for Reactor Trio and Anticicated Transients Without Interviews with control room operators were conducted by NRC staff, and a review of the operating procedure for ATWS and reactor trip (EI-4.3) have revealad'that a) the operators de net take immediate action to initiate a manual trip based on reactor-trip 11first-out11 annunciators, b) they were not directed to do so by the procedure; however, the procedure did require a manual trip if an automatic reactor trip Si~ net occur.

The procedure required only evaluation of reactor power level remaining high and/or multiple control rods failing to insert, and c) at least one operator questioned the appropriateness of the ATWS procedure's *step to trip the turbine, without first verifying that the reactor had tripped,. since that results in a loss of heat sink..

Based on these disc:us~fons with operators, the staff believes that the revised procedure dated March 2, 1983, would not have substantially changed the operators' response due to a perceived need to evaluate plant status from contra l room i ndi cations *.

Licensee Action - Short Term

l.

The NRC will require the licensee to identify the indications in the con-trol room that provide positive indication, without operator analysis or verification, that an automatic reactor t~ip demand is present.

• 2.

The NRC will require the licensee to revise procedures to direct the operators tO insert a manual trip whenever positive indication of an automatic trip demand is present without delaying to evaluate the overall plant status.

3.

The NRC will require the licensee to review the basis for the ATWS proce-dure steps and order of p~iority in light of the operators' concern, revise the procedure as necessary, and train the operators on the basis for the procedural steps and importance of procedural compliance.

4.

The NRC will require that all operators be trained on the revised proce-dures prior to restart of Unit l.

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"Licensee Action - Long Term The NRC wi11 require the licensee to incorporate any procedural changes for Unit 1 into Unit 2 procedures and retrain Unit 2 operators on revised Pr-9ce-dures prior to*Unit Z restart.

NRC Action - Short Tenn NRC wi 11 review the adequacy of 1 icensee' s re~i sed procedures and basis *for the procedural steps and order of priority.

NRC will also review the adequacy of the Westinghouse Owners Group, Emergency Operating Procedure Guidelines.

Z~ Operator Training Interviews conducted by NRC with the 1jcensed operators who were onshift during the two* events indicata a lack of familiarity with the functions of the annunciat::>rs and indicators associated with RPS.

The interviews also revealed that. the operators who were onshift during the February ZS event did not recognize that a failure of the RPS had occurre~ until *approximately 30 minutes after the event. Specifically, the operate'!"! interview~d were not able to describe whether the reactor-trip-indicator light (red) on the RPS mimic status panel indicated a demand for or confirmation of a breaker trip.

Interviews also indicated that at least scme*operators questioned the validity of annunciators until they could be confirmed by independent indication. This need to verify caused the operators not to take immediate action to trip the reactor based on annunctator indication and verifi~atian of reactor power level remaining high and/or mu1tfp1e cantrol rods failing to insert on February 25, 1983 as discussed in operator response issue B.3.

In any event, it is apparent that training in the areas of the RPS and associ-ated indications and alarms is warranted~

Licensee Action - Short Term The NRC wi11 require the licensee to conduct the additional training r~quired in issue*S.l and additional training on the RPS and associated indications and

• alanns (specifically whether these are demand or confirmatory and the use of this information), and to review the February 22 and 25 events with all operators.

Licensee Action - Long Term The NRC will require the licensee to assure t.iat RPS training and associated subjects in the operator qualification and requalification program address the areas of (1) logic function of the RPS and (2) operation of the RPS and asso-c:iated indications. This training shall.be incorporated in the ongoing regular training programs.

NRC Action - Short Term NRC will evaluate the adequacy and completion of remedial training prior to Unit l and Unit 2 restart.

NRC Action-Lona Term NRC staff will audit the licensee 1 s requalific~~ion.program.

3.

Otlerator Resoonse Interviews with oper~tors on shift for the February Z2 and 25, 1983 events and with I&C and maintenance personnel disclosed the following:

a..

In both events, the operators took. 20 to 30 seconds to determine the overall plant.status and initiate a manual reactor trip.

For the first event, this evaluation began with the electrical bus transfer failure.

This evaluation was necessary because of the resulting large number of alarms and lost equipment controls and status indicators.

This eval~

uation time was nearly identical to the time it took for the plant conditions to degrade causing the RPS to provide an automatic reactor trip signal.

For the second event, the evaluation of the plant status began when the reactor trip annunciat~t actuated and the evaluation determined that a reactor trip was in fact necessal'7t based on plant parameters and contro*l room indicators. This time could have been shcrtened had the operators recognized that an earlier valid trip was called for by the RPS.

b.

During the first event, after an operator was directed to manually trip (scram) the reactor, the switch handle was not operated correctly.

When the SRO called for a manual trip, the control handle was inadvertently pulled off the board and had to be reinserted to perform the manual trip *.

Because of the near coincident autom*atic trip signal, this may have con-tributed to the operator's failure to recognize that the automatic trip system had called for a trip and had faiied to trip the reactor prior to the manual trip *

. c.

In *spite of the positive indication of the reactor protection system failure during the second event, the operators neither understood nor trusted the indications.

Because of this the operators unnecessarily reevaluated plant status.

The operators manually tripped the reactor in response ta their evaluation of the plant status and control room indi-cators and not due to recognition of the failure of the reactor protec-

d.

tion system.

NRC was initially informed by licensee I&C and maintenance personnel that the first out panel and RPS logic systems are highly reliable.

Based on this information and the NRC 1 s general understanding of the *1 ogi c of these systems, the NRC concluded that the information provided in the Salem control room (i.e., first out panel alarms, illuminated RPS dis-*

plays, and safety grade instruments) was adequate to enable operators to immediately identify an ATWS event.

Subsequent to this initial 13

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conclusion and based on NRC questioning of the licensee on March 3 and 4, the licensee conducted tests which indicated that short-duration signals (less than 10 milliseconds) could produce a reacUlr trip annunciation on the first out panel and a computer printout indicating a reac:tcr trip without initiating the reactor protection systemc Howevers after review-'*

ing test results, the.licensee concluded that the testing indicated the system was f1.1nctioni11g as designed and that it required trip si*gna1s *of.

mare than 10 U:! l2 milliseconds duration.to actuate* the reactor-trip circuit breakers and seal in the reactor protection, systamc Accordingly, the current design of the first out pane1 can result in operators ques-tianing the M!liability of the information provided on.this panel.

Based on the above, the HRC concluded that for the event on February 22, the operattlrs' response was prompt and fully satisfactory.

For the event on February 25, taking into accoufit the defieienc:y in the reactor trip procedure and deficiencies in training that resulted in (l) operators **failing to recog-nize an* RPS reactor trip demand and (2) the operate rs failing to understand the control room indications, the operators' response time was reasonable.

Licensee Action - Short Term le The N~C will require that in addition to the training required in issue Z, operators must be cautioned on.th~ use of the manual trip."J 11 handle central.

licensee* Action c Lona Term lo The NRC will require the licensee to evaluate alternative means to permanently secure the 11J 11 1Tand1e as part of the Cetailed Control Room

. Design Reviewc

2.

• The NRC wil 1 require the 1 icensee to reevaluate the design of the first out panel systam with regard to the *reliability of information presented to operators, as a part of its detailed control room design review.

NRC Action - Long Term

l.

The NRC staff will evaluate the 1icensee 1s findings and corrective actions related ta these long-term actions as part of the NRC review of the licensee's detailed control room design review.

The licensee's schedule for completion of the detailed control room review will be sub-mitted for staff review on April 15, 1983.

14

• • --~*.. _.

C.

Manacement Caoabi1itv and Performanca The deficiencies identified during the l"'eView of circumstances surrounding t~ese eve~ts raises the question of the responsiveness, practices, and capabi-lity of 11censee management at the corporate and station level. Additionally, a number of specific management issues directly related to the failure of the reactor trip breaker events were also identified. The issues discussed in this section are:

l.

Overall Management Capability and Performance

2.

Master Equipment List

3.

Procurement Procedures

4.

Work Order Procedures

5.

Post Trip Review 60 Timeliness of Event Notification

7.

Updating Vendor Supplied Information

8.

Involvement of QA Personnel with ot~-~tation Depar~~ents

9.

Past Maintenance Operabi1fty Testing*

l. Overall Manacement Capability and Performance Historically, PSE&G management has-not displayed the expected aggressive effort to self evaluate and redirect efforts to correct internally identified problems.

However, the licensee has responsed the specific evaluations con-ducted by external organizations s*uch as INPO, NRC and consultants.

Each of these are discussed below.

The 1981 INPO evaluation identified opportunities for improvement in *numerous areas inc1udin~ staffing, personnel safety practices, adherence to procedures, control of documents and design changes, availability of technical support, operating practices with respect to inoperable alanns and tagouts, shift turnover procedures, and goals and objectives.

Based on cintinuing observation, the licensee responded positively to selected findings by various actions although the effectiveness of these ac:tions has been less than expected.

The ar9a of preventive maintenance, beyond that required by technical speci-fications, was also raised as an issue by INPO in 1981.

The licensee instituted a program to be responsive to this INPO concern, but the recent 1982 INPO report sti11 contains Findings and Recommen~ations and identifies a target date for completion of this effort in February 1983. It should be noted that the reactor trip breakers were identified by the licensee for inclusion in

• this program.

15

- --*---*,- --*----*---:-**-. *---~-----**

e*

Based on the 1982 !NPO repcrt additional findings we~ identified in the areas of industrial safety, use of ttie computer tagging system, backlog* of work orders, drawing revisions and plant modifications, adherence-to established radiation protection prgcedures and policies, and material and housekeeping conditions ilT*the axuiliary building and intake structures.

Four SALP assessment we~ conducted by the. NRC. during the period October isao Oc:taber 1982.

The earlier assessments identified weaknesses in the areas of: :

design cnange documentation, engineering support responsiveness, health physics, physical security and ove~al1 management fallowup ta numerous areas.

The later SAL? assessments acknowledge licensee management attention-to, and improvements in the areas of, design change tracking and documentation and health physics.

Physical.security, despite several initiatives on the part of the licensee to improve the areaf continued tc be weak.

Very recently, the licensee has dedicated considerable resources to physical security which, if properly implemented, should facilitate a number*of hardware improvements and add several managers to the organization to more effectively.monitor security activities on a day-to-day basis.

The mast visible ccmmittment made by the licensee are organizational.

During the licensing process for Salem Unit 2 in 1981 7 the licensee made a decision to place all activities, including engineering under a single vice president.

Ccmmitt.~ents were made ta recall these activities f'l"'Cm the corporate offices in Newark, Hew Jersey U> the site located_in Southern New Jersey. While the li~ensee was hopeful that such relocation of *the engineering staff, including QA personnel, to tha site would prove more effective, the process has moved m~ch more slowly than hoped and has even resulted in the loss of certain personnel.

As late as January 1983, the QA department was~p1aced in the Nuclear Department, and began moving ta the sita. The organizational and location changes have now been in transition for. almost 18 months.

Station organizational changes were also made to focus effort approiately and a number of new data management systems were installed to track issues for management fo11owup.

With respect to safety review committees, NRC inspection experience has shown that the onsite and offsite review committees are properly constituted, meet frequently, and ask cogent questions.

Since licensing of Unit 2, the licensee has maintained a separate independent Safety Review Group (SRG) with

• a general charter to identify and evaluate safety1ssues.

In response to an NRC request, the licensee has agreed ta evaluate the effectiveness of the SRG in terms of types of issues addressed and more importantly, the approach tc and timeliness of the licensee's response to such recommendations.

PSE&G management is generally capable and has been willing to make changes to improve safety.

While the licensee has demonstrated his ability to react to external direction, and strong se1f~ass~ssment p~ogram has not been effectively carried out that would identify the specific deficiencies identi-fied by the several external review efforts discussed previously, or of equal importance, to identify and rectify their root causes.

16

Licensee Action-Short Term NRC wi11 require the licensee tO determine whether the currently identified problem: with the reactc~ trip breakers are indicative of broader based pro-blems with th~ administrative and managerial control system.

• ~

Licensee has committed to evaluate the effectiveness of the independent SRG in terms of issues addressed and resolutions.

In.particuTar, the evaluation should address the role of SRG with respect to the August 1982 and January 1983 reactor trip b:eaker problems.

NRC Action - Short Term NRC will review the licensee's evaluations and will require the licensee to address any broader based problems identified as a result of, that evaluation.

Licensee Action - Long Tenn Continue management initiatives aimed at improving organizational respon-siveness to identifying and resolving problems, part1c:u*larly in the areas of procedure adequacy and adherence.

NRC Action - Long Term Continue to review the adequacy of management* control and timely resolution of problems through an augmented inspection program.

Z~

Master Eguicment List The licensee maintains a Q list that identifies activities, structures, and systems to which the Operational Quality Assurance (QA) Program applies.

A Master Equipment List (MEL) is used by the licensee as the reference document for determining the safety classification.of individual equipment.

The MEL is intended to be a comprehensive list of all station equipment and identifies each item as nonsafety n!lated or safety related. *when preparing maintenance work. orders, the MEL is consu 1 ted to determine if QA coverage of the wo rlc. is necessary.

Licensee and NRC review identified three problems associated with the MEL.

These problems are, l) the accuracy and completeness of the docu-ment, 2) *issuance as a noncontro11ed document, and 3) lack of understanding by plant personnel of its proper use.

The MEL was derived from engineering source documents and a construction program do.cument called Project Ci rect.ive 7 (P0-7) and was provided to station personnel by the Engineering Department as a reference document in Ju1y 1981.

Prior ta issuance of the MEL, the P0-7 was used as the reference document.

The MEL, however, was not issued as a controlled document, therefore verifica-tion of its accuracy and completeness on issuance was not assured, and it was not updated in the plant as necessary.

The reactor-trip circuit breakers were not included in the MEL.

In addition, some person~e1 were not familiar with how to use the MEL for det~rmining the classification of a particular piece of equipment.

Maintenance personnel acknowledged that reference was made to PD~7 an occasion during the January - February 1983 period.

1.

17

Licensee Action - Short Term The NRC will require that the licensee:

lo Verify the MEL is complete and accurate with respe~t to emergency core cgoling (ECCS) including actuation systems, R?S, auxiliary feedwater, and containment isolatian systems.

2o Instruct appr~priate personnel in the puri:)ose and use of the MELo Licensee Action - Long Term NRC will" require that the licensee verify the completeness and accu~acy of the MEL and reissue it ~s a controlled document.

NRC Actian ° Short Term NRC will perform sampling review of the MEL on the above systems.

NRC.,*Action - Lang Term NRC will confirm completion of the licensee's long-term action.

• 3.

Procurement Procedures A review of safety and quality classifications for the reactor trip breakers indicates that the li~ensee's established management and administrative controls allowed the procurement of replacement c:cmponents for a safety system*

with a quality less thari that of the arigina1 design.

This is evidenced by procurement activities concerning the purchase of reactor trip breakers and replacemen~ c:cmponents conducted during the period from June l, 19Sl to March l, 1'983.

One example involved the issuance of a purchase order for a spare react~r trip breaker on June 1 9 19Sl.

Contrary tQ the established administra-tive controls; the breaker was classified incorrectly; the proper review and approval was not conducted; and no QA requirements were imposed as required

~ for the original equipment.

Subsequently, on September 15, 1982, the classi-fication for the same order was changed to an even more inappropriate classi-fication without the required review and approval process.

As a result of*

these activities, the purchased breaker was received and placed into storage, without further use, without appropriate documentation that would demonstrate suitability for its use had it been required.

All subsequent purchases for reactor trip breaker components consistently utilized *the initial incorrect classification.

A spare c:oil for a UV trip attachment purchased in this manner may have been utilized on August 20, 1982.

Though the procurement review focused on the reactor trip breaker, the licensee's activities in the area for other safety related components could have resulted in similar. circumstances existing for plant safety systems.

Licensee Action - Short Term NRC will require and the licensee has made a commitment to have the procure-ment procedures evaluated and modified as.required to ensure that the appro-18

.. 9

.I priate classification is being applied to items and/or serv.ices important to _

s~fety. Pending satisfactory resolution of this item and a commitment by the licensee to develop and implement a program comparable to that described under Long Term, the staff considers this issue sufficiently resolved to permit restart.

Licensee Action - Long Term The licensee wi11 review the organization relat.ionships involved in the procurement process and assess the current management controls to provide and ensure that departure from expected performance of personnel involved in the procurement process wi11 be appropriately flagged for management attention.

Additionally, the licensee will formulate a plan to review and assess on a sampling basis the procurement process as it relates to all prior procurement activity on systems important to safety. The plan will address the schedule, and criteria to be applied for an accelerated sampling based upon initial finding.

4.

Work Order Procedures The review identified that the personnel preparing maintenance work orders were not complying with instructions contained in the station administrative procedure.

Specifically, for the work pe.c..formed on the reactor-trip circuit

• breaker in January 1983, the engineering department was not consulted to verify safety classification, and an erroneous nonsafety'determination was made.

Such consultation is required if equipment is not listed in the MEL.

There was, therefore, na independent review*within the maintenance organiza-tion, and the Quality Assurance Department was not involved in the work.

• Historically, there was no requirement for QA personnel to be involved in the review of work orders.as they were processed to assure that appropriate steps

'#ere taken to assign classification. It should be noted, however, that a11 other work orders for maintenance or services on the reactor trip breakers were found to be properly designated safety-related.

Licensee Action - Short Term The licensee has made a commitment to have the QA Department review all non--safety related work orders prior to starting work, and to implement a program and training to ensure that work orders are properly classified.

NRC will require the licensee to review work orders written since issuance of the MEL for proper classification and will evaluate safety consequences of those found improperly classified.

NRC Action - Short Term NRC will review licensee's work order classification program.

5.

Post-Trip Review The licensee did not determine that there had been a failure to trip on February Z2 until the computer printout of the sequence of events was re-19

-~--**---

L evaluated on February 26, as a result of NRC inquiries. Although the licensee conducted a review of each trip, there was no formal procedure for conducting a systematic review.

By letter dated March 1 9 1983, the licensee made a commitment to develop a post-trip and post-safety injection review procedure.

The procedure will specify the review and documentation necessary to *determine the cause of 'the event and whether equipment functioned as designedo Otner.

key elements of a post~trip.review procedure are l) necessary management authorization for restart 9 2) debriefing of affected-operators, 3) verifica-tion that reporting requirements were completed*~- and 4) followup review by safety c~mmittees. Furthermore, the affected individuals who will be required by procedure to review the sequence of events computer printout snd other event recortis wi11 need to receive necessary training in the proper interpretation, understanding and evaluation of these records.

Licensee Action - Short Term NRC wi11 require and the licensee has committed to develop and issue a post~

trip and post-safety-injection review procedure and train appropriate Opera-tions Department personnel on the. requirements prior to Unit l restart.

NRC Action - Short Term NRC will review the licensee's postmtr1p and post-safety injection review procedure U> ensure the key elements no~ed above are adequately addressed.

6.

Timeliness of Event Notification On three occasions between January 30 and February 25, 1983, the licensee notified NRC of significant events-belatedly.

In each case, the notification was approximately.30 minutes late; Two of these reports ~re for the February 22 and ZS events.

Furthermore, in the February 22 eventf the first notifica-tion did not contain lcnown significant information regarding actuation of engineered safety features and opening of the power operated relief valves.

This additional information was provided*approximately 40 minutas later. The*

notification procedures used by the licensee warrants further evaluation as to the priority assigned for NRC notification.

Licensee Action - Short Term

'NRC will requira the licensee to reemphasize reporting requirements with all shift and on-~all management personnel and will reevaluate notification priori ti es.

NRC Action NRC will confirm that licensee's short term action is completed.

7.

Updating Vendor Suoolied Information As a result of the February 25, 1983 event and NRC IE Bulletin s3~01, the 1ic:ensee indicated not bei'ng aware of the existence of two Westinghouse technical service bulletins that provided preventive maintenance recoirunenda-tions for the reactor-trip circuit breakers. The t~o documents in question 20

• • -*--*~~---~~--*,4-.-----~-~----..,....

--,----=-----.....:""-----------------* -:.. **-*--*-=---.

w~re published by Westinghouse in 19i4.

The licensee has requested documenta-tion for all Westinghouse equipment and will incorporata this information into station documents.

While we are not-aware of any problems with other vendor documentation, an NRC staff concern is whether a similar situation exists with respect to documentation for other vendor-supplied information.

Licensee Action - Short Term The licensee has made a commitment to.a program to update existing documenta-tion on safety equipment and to ensure that vendor documentation is under a controlled systemc Licensee Action - Long Term The licensee will complete the above program in a timely manner.

NRC action - long Term NRC will perform inspections to verify the implementation of licensee's program.

8.

Involvement of QA Personnel with Other Station Oecartments _

The Quality Assurance Department did not review maintenance work orders associated with repair of the react.or-trip circuit breakers in January 1983 because the work was not designated safety related.

Further examination d~termined that the QA D~partment does ~ot review for proper determination of

- classification the work orders de~ignated nonsafety related by other depart-

.ments.

Discussions with the licensee indicate that the QA Depar-tment has been somewhat isolated from the activities of other departments.

As a result of prior decisions, the licen~ee had initiated steps in January 1983 to relocate the QA Department from the corporate offices in Newark, N.J.

to the site and is taking steps to increase QA Depart~ent involvement,-*in other station activities. Completion of this program of increased QA involvement with other station activities need not be completed prior to restart, because completion of short-term actions in management issues 5 and 6 is sufficient to correct. QA deficiencies in the short term.

Licensee Action - Short Term

, The licensee has made a commitment to institute a program to more fully integrate QA activities into the overall activities.

Licensee Action ~ Long Term The licensee will complete the above QA integration program.

NRC Action - Lona Term Monitor licensee's implementation of the above QA integration program.

9.

Post-Maintenance Ocerabilitv Testina 21

Past practice at Sa.lem for post maintenance operability testing has varied.

Such testing may be specified by the preparer of the maintenance work order or left to the discretion of maintenance personnel.

For safety-related equip-ment, post-maintenance surveillance testing is done before returning the equipment to service.

Additional functional post-maintenance and repair=

testing of equipment, such as surveillance testing~ may need to be performed ta demonstrate operability as an integral part of the lar.ger component or system in which it must function.

Licensee Action - Lona Term The licensee will review and revise procedures and practices as necessary ta ensure that functional testing of the overall components or system is per-formed to demonstrate operability prior to returning the equ~pment to service following maintenance and repair. Procedures will be revised, as necessary, to assure that operations department personnel review the testing prior to returning such equipment to service.

NRC Action - Long Term NRC wi11 review licensee's revised procedures and their implementation to assure that appropriate post maintenance operability testing is being accom-plished before equipment is returned to service.

Appendix A

~ULTS OF NRC SiAFr EVALUATION OF EVENTS AT SALEM NUCLEAR GENERATING STATION I.

IDENTIFICATION OF CAUSE OF FAILURE Summary and Initial Findings Initial inspection of the UV trip attachment indicates a possibility of multiple contributing causes of failure.

Possible contributors are (1) dust and dirt; (2) lack of lubrication; (3) wear; (4) more frequent operation than intended by design; (5) corrosion from improper lubrication in January-1983; and (6) nicking of laU:h surfaces caused by vibration from repeated operation of the breaker.

The contributors appear to be cumulative, with no one main cause. The initial investigation indicates that the failure was age related and that a new device would perform properly.

Many surfaces of the latch mechanism are worn and the additional friction tended to prevent proper operation.

Proper lubrication throughout the life of the device might have

prevented the wear that can be seen on the sample.

The tests and examinations proposed by the staff and ~ts contractQr will attempt to determine the cause of failure_a~d if possible reproduce it. The following sununarizes the initial findings and lists the ~reposed tests.

Discussion and Circumstances A site visit was conducted on March 3, 1983 by NRC and Franklin Research Center personnel to inspect the type 08-50 circuit breaker undervoltage trip attachment in an effort ta determine the most probable cause of failure.

The reactor trip circuit breaker rooms for Units l and 2, each of which contain four 08-50 circuit breakers, were visually inspected and the following obser-vations were made:

l.

All" four OB-50 Unit l circuit breakers and UV trip attachmeQts were removed from the circuit breaker cabinets.

The enclosures were generally clean and free of dust. - The ambient temperature was between 85 and 95°F, with warm exhaust air from inverter cabinets being directed at the OB-50 circuit breaker cabinets.

The spacing between cabinets is approximately 3 feet *.

2.

All four 08-50 Unit 2 circuit breakers were also inspected.

The UV trip attachments were removed, however.

The circuit breaker cabinets con-tained a layer of loose dust approximately l/16 inch thick.

The ambient temperature was in the 70°F range.

UV trip attachments are mounted on the top of the circuit-breaker platform, to the right of the shunt trip attac~ment, which is several inches from the bottom of the circuit breaker cabinet.

Interviews were conducted with an electrical maintenance supervisor who discussed the circumstances of the removal of the circuit breakers that were involved with the incident on Unit l, anQ an electrical supervisor who had 23

(.. ::

• ~-

.. ~:

.:1 also worked on the circuit breakers in question in August 19S2.

The informa~

tion received was that the circuit breakers and their UV trip attachments had been operated frequently and had operated du~ing surveillance testing within a few days prior to the incident.

I A request was made to Salem management to provide one of the UV trip attachc ments and a shunt trip attachment far testing at Franklfo Research Center (FRC).

This request was complied with, and an, investigation of these devices is now under way at FRCo Results of Initial Examination Initial evaluations indicated roughness in the operation of the trip latch.

There is some dragging of the mechanism>> and portions of the latc:h mechanism have obvious signs of wear.

Possible contributing factors to the failure to operate are a lack of lubrication>> wear, jarring of the UV attachment as a result of circuit breaker operation and more frequent operation of the UV trip attachment than was intended during design. It is postulated that under most industrial applicationss the UV attachment would be used very infrequently and probably would be operated only during test sequences at perhaps yearly or longer intervals. Therefore, in industrial applications, it would operate only a few times, perhaps 20 or 30 cycles during its lifetime, and would not be a normal_ tripping mechanism for the breaker.

However, in its use at Salem and other nuclear power plants, it is.the,-P.rime tripping device for the circuit breaker, and is therefore called upon ta operate on the order of 50 times per year. This would mean that at its current age: in 1983, there would have been possibly 400 to 500 trip opera~icns af this device.

During the initial*eva.lu-aticn it-was noted that the shu.nt trip attachment has been operated once every seven* days since August 1982>> rather than at longer intervals. This means that the circuit breaker is tripped and closed every seven days.

This causes jarring of the entire mechanism of the circuit breaker and its attached reJays and coils due to the normal operation of the.

breaker. This may or may not be significant, but it should be noted that the UV attachment stayed energized during these trips, and its latch mechanism was jarred somewhat by operation of the circujt breaker. This possibly added to the friction bui1t up in the latch mechanism from normal operation by causing the latch mechanism to just slightly nick the surface that it rides on and

. thereby*tend to prevent operation. Further investigation wi11 try to deter-mine whether this is indeed a problem.

It appears from initial inspection o.f the device that wear and n:iughness of mating surfaces in the trip latch are present.

Proper lubrication might have prevented the curNant situation or could have reduced the roughness to the point where proper operation could oc~ur.

Further investigation will attempt to determine whether the CRC-2-26 lubricat-ing and cleaning spray added to the operating problem by either causing corrosion or removing all. residual lubrication from initial construction and possible caking of dust a~d dirt. It appears that from the time of initial construction of the UV trip attachments up until January of 1983, no lubrica-tion procedures had been performed, and then, in January of 1983; lubrication procedure? were undertaken by the maintenance personnel and a Westinghouse 24

. ~---~*---*-* ~----* ---*-*--*-:r*---~~.,..~

technician.

At this time, the CRC-2-26 lubricant cleaner was sprayed on a11 four UV trip attachments associated with the Unit l circuit breaker.

This 1ubricant is being procured by FRC for testing purposes.

List of Investiaations To Be Performed bv*NRC Contractor (FRC)

l.

The ~irst test will be to perform various deene_rgizations and energiza-tions of the UV trip attachment and monitor the device under various conditions.

2.

The second test will be to disassemble the latch mechanism to observe the surfaces of the various parts of the latch and to photograph these sur-faces through a mic:rosccpe to determine the various levels of wear on these surfaces.

3.

The third test is to determine the effects of CRC-2-26 *spray on the various types of metals used in this devices.

An attempt will be made to use metals other than those. in tha actual attachment.

If possible, the chemical consistency of this spray will be determined from the manu-facturer.

To prove. that the sample UV trip attachment is identical to all such Salem devices, a visual inspection of all existing Salem Unit 1 and 2 UV trip attachments will be performed.

This can..ta~e place at Salem, with no disas-sembly needed.

The inspection can be made*wi"th the devi~es mounted on the circuit breakers or loose.

These inspections should be done as soon as possible, and Tuesday, March 8, 1983 is reconunend~d.

If further tests are required they_will be based on the results of these initial tasts. All.tests will be--nondestructive such that the device can be used for further testing and returned to the utility.

Additional Test To Be Conducted bv the Licensee, as Revised bv NRC Staff This test will require the use of a spare circuit breaker.

The UV trip and shunt trip attachments will be mounted on the breaker, and the breaker will be operated repeatedly tc determine the effect on the shunt and UV trip attach-ments.

It is sunnised that while the attachments are energized and the

.breaker trips and closes a number of times, additional friction of the trip latch may occur from the vibration.

Thi~ test is described in detail in the following sectiono.

II.

REVISED SURVEILLANCE OF REACTOR-TRIP CIRCUIT BREAKER OPERATION ANO VERIFICATION TESTING The licensee proposed the following increased surveillance of reactor-trip circuit break.er operation:

1.

Main and bypass breakers will be shunt-tripped weekly.

2.

Main breakers will be UV-tripped monthly.

25

~~~~~=~-

• ~:.

k,

~

The accaptabi1ity of this revised surveillance of reactor--trip circuit breaker operation has been evaluated by NRC staff. Based on an analysis conducted by NRC staff, which considered reactor-trip system unavai1ability, reactor-trip circuit breaker failure rates, and test intervals, the following conclusions we~ drawn.

First, the preposed test of each reactor-trip circuit break.er 'JV trip attachment once every 30 days is acceptable.

Second, the proposed test of the shunt trip attachment once every seven days is considered to be exces-sive and may impact on* the reliability of tha-~actor trip system by increas-ing the potential for a single failureo During.testing, a single failure in

• the logic portion of the reacU1r trip system could prevent an automatic SCRAM.

Thus, it is recommended that the shunt trip attachment be tested on the same schedule as the UV trip attachment; that is, once every 30 days. It is also recommended that the UV trip of the bypass breakers be tested prior to restart and every refueling thereafter.

Discussion The acceptability of the proposed test intervals for the reactor-trip circuit breakers was based on NRC staff review cf reactcr-t~ip circuit breaker failu~

rate data obtained from Licensee Event Reports (LERs).

The generic RPS unavai1abi1ity of 3 x 10-s (used in both NUREG-04SO, "Anticipated Transients Without Sc:ram for Light Water Reactors, 11 and by the ATWS Task Forc:e and Steering Group in the development of the proposed An/S Rule} was used in evaluating the licensee's prt1posed test i.!J1ervals.

In addition~ the 1o11owing considerations were incorporated into the HRC staff reccmmendation:

la

z.

The shunt trip attachment provides a diverse means of tripping the reac:tDr-trip circuit b~eaker, which is electrically independent of the UV trip att:achment.

The-UV triJf _attachment is supp 1 i ed. by a 48-V de source and is deenergized ta trip. The shunt trip attachment is supplied by a 12.S~V de source and is energized to trip.

The shunt trip attachment is an energize-to-actuate device and is not "fail safe11 in that a less cf power wil 1 not c::ause a trip. However, the shunt.trip is powered from a reliable Class lE battery-backed source.

3.

Since the shunt trip attachment is an energize-to-actuate device, it is net subject to the constant heating effects that the continuously en-ergized UV trip attachment experiences. ihe heating effects may contrib-ute to the higher failure rate of the UV trip attachment.

4.

The mechanical.construction of*the shunt trip ~ttachment is less complex than that of the UV trip attachment.

The shunt trip attachment does not re1y on*the successful operation of the complex latching mechanism that has been determined to be the source of the majority of the failures of the UV t~ip attachmentc

5.

The majority of the electrical circuit breakers used in the high-voltage electrical distribution system have de-powered energize=to~actuate shunt trip atta~hments. These circuit breakers are used for manual, as well as automatic, trip functions for load shedding and power switching.

Relia-bility of energize-to-actuate shunt trips in similar applications through-26

---

.. ----***--*--~* -.

.~~-*-~~-*--"'!'"**

out the nuclear power industry has been shewn to be significantly higher than for devices that are constantly energized.

6.

Over 70% of the known reactor-trip circuit breaker failures ~ere cau~ed by UV trip attachment failures.

7.

Most of the concerns relating to the events at Salem on February. Z2 and

• 25, 1983 are related to the operation of*the UV' trip attachment.

During*

the events at Salem, the *~hunt trip attachment functioned properly.

8.

Tne bypass breakers are required to trip in response to a UV trip demand signal should this occur when the main breakers are being tested.

Since the test frequency of the main breakers has been increased, the bypass breakers should be tested to verify the capability to perform their backup safety function.

Verification Testing It is recommended that a bench test be performed on one OB-50 reactor-trip circuit breaker.

The purpose of the test will be to cycle the 08-50 with the

'J'J trip and shunt trip attachments in place for a total of 2000 cycles to determine if any adverse effects can be identified and, if there are no adverse effects, show that a properly maintained breaker and its subcomponents can operate for an extended number of eye.le~. The breaker will be tripped, with each cycle being alternated with the UV and shunt t~ips. The ambient temperature should be l00°F to simulate the expected service environment, and the circuit breaker. should be c:ycled no more often than once every 30 minutes to allow for return to steady-state conditions.

The results of each circuit breaker operation will be documented and a visual check made.

Additional details for this type of test wil1 be provided at a later time

• 27

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Appendix a INITIAL NRC STAFF REVIEW OF LICENSEE'S MAINTENANCE PROCEDURE AND PREOPERATIONAL VERIFICATION PROGRAM NRC staff rev1ewed the licensee's maintenance procedure, Salem Generating Station Maintenance Department Manual Maintenance Procedure M3Q-2 9 Revision l.

This document includes a procedure for verifying proper operation of the UV trip attachment and testing of the UV trip attachment coil following replace-*

ment.

NRC staff also reviewed the 1icensee 1s proposed reactor-trip circuit breaker operational verification program, which references Procedure M3Q~2.

The following comments and recommendations wen1 made concerning these docu-ments:

1..

The maintenance procedure does not spec::ify whether the maintenance and testing described are applicable to both the main and bypass breakers.

It should specify that it does.

2.

The maintenance procedure should specify required actions to be taken in the event any acceptable tolerances, as identified in Enclosure 7 of

3.

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• • M3Q.. z. are not met.

The frequency of all maintenance and testing specified in the procedure, with the-exception of the verification tasting identified following UV trip attachment replacement, should bl! specified.

The procedure should be modified to require cleaning of the entire circuit breaker room, the removal of all four circuit breakers and cleaning of the cab1nets by'~.lacuurning, and cleaning of the b?"eakers during every refueling outage.

Section 9.7.2.l of Prccedure M3Q-2 specifies that the UV trip attachment is to be cleaned with a standard solvent.

The procedure should specify the exact solvent to be used.

NRC will request FRC and.SNL to determine*

the adequacy of the proposed solvent and any potential adverse effects from its use.

(This evaluation need not be completed prior to plant startup).

6.

Section 9.7.2.2 specifies the composition of the lubricant to be applied to specific points of the UV trip attachment. This specification should state whether the mechanism is to be lubricated each time maintenance is performed.

NRC will request FRC and BNL to determine the adequac; of the lubricant and the points of application specified, as well as the fre-quency of lubricationo

7.

Any UV trip attachment that does not successfully complete the 25 consec-utive cycles of testing to be performed by Westinghouse should not be accepted or installed by the licensee.

a.

Section 9.7.4.15 specifies the testing to be performed on the UV trip attachment coil following its replacement.

The maintenance procedure.

should be revised to require that all replacement UV trip attachment succ~ssfully complete 25 consecutive cycles of testing prior to instal-28

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lation in the plant and start of the ten test cycle specified in the maintenance procedure.

The time between each of the ten tests should be specified.

• NRC recommends 30 minutes for the reasons specified in..

Appendi~ A.

NRC staff believe the increase in test cycles, and the-acceptance criteria specified if any failures occur during this testing, are reasonable and should be incorporated into maintenance procedure M3Q-Z.

9.

Technical Oepar~~ent Procedures Nos. IIC-18.l.Oll and IIC-18.1.010, referenced by the 1icensee, should be reviewed and their acceptability determi.ned by NRC staff.

Following revision of the maintenance procedure and the associated proposed reactor-trip circuit breaker operational verification program to incorporate the above comments and recommendations, the NRC staff wi11 reevaluate the documents and provide another report that will include the results of the NRC contractor 1 s evaluations and will document the final NRC evaluation and conclusions concerning the adequacy of the maintenance p~cedure and preopera-tiona1 verification program.

29

e UNITED STATES OF AMERICA NUCLEAR REGULATORY COMMISSION In the Matter of PUBLIC SERVIC; ELECTRIC AND GAS COMPANY

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Docket Nos. 50-272 and 50-311

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(Salem Nuclear Generating Station, Units 1 & 2)

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License Nos. OPR-70 and DPR-75

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ORDER TO SHOW CAUSE I.

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Public Service Electric and Gas Ccmp~ny (the l_icensee) holds License Nos.

DPR-70 and DPR-75 which authorize operation of Units 1 and 2 of the Salem Nuclear Generating Station.

The facilities are Westinghouse pressurized water reactors (PWRs) located at the licensee's site at Hancock's Bridge, Salem County, New Jerseyo.

IL On February 2S, 1983, an event occurred at Unit 1 of the Salem Nuclear Generating Station when the control rods failed to insert si nee the reactor-trip circuit breakers failed to automatically open following receipt of a valid trip signal from the Reactor Protection System (RPS).

The manu~J trip system was used to shut down the reactor.

Subsequently, it was concluded by the licensee that the failure to trip was caused by a malf.unction of the undervoltage (UV) trip attachments in both reactor-trip circuit breakerso Evaluation of.the event of February 25, 1983 revealed that a similar failure had occurred on February 22, 1983, at Salem,1.

There had also been a previous event at Salem 2 in~

valving a failure of one reactor trip circuit breaker to trip on January 6, 1983.

The ma 1 function of the *undervo1 tage device on February 25 was detenni ned by the licensee and the vendor (Westinghouse) to be excessive friction on the mechanica1 latch lever in the UV trip mechanism.

It appears that no preventative maintenanc~ was conducted on the Sa1em 1 DB-50 circuit -

breakers until January _1983.

Addi ti ona 1ly, the recommendations of a Westinghouse 1974 Technical Bulletin and Data Letter (NSD DATA LETTER 74-2) were not implemented during the January maintenance since the personnel who perfonned the maintenance were not aware of the bu11etin recommendations.

The specific details o.f the event and the licensee's response are contained in the NRC Restart Status Report of March 1983.

The NRC review of the event revealed a number of management inadequacies, such as the management supervision and control of the procedures governing the

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classification of equii:ment as safety=related equii:ment, management supervision*

of maintenance techniques, and management attention to the safety implications of system ma1functionso If there were a potentially severe transient, from a worst case set of initial conditions, and the reactor shutdown system did not function, an extr~~ely severe accident could occur in the absence of time1y operator *action.

Therefore~ the technical significance of the afore-mentioned failures is readi1y apparent, and when coup1ed with *the cause of t~e cha11enge to the reactor protection system, i.e., a feedwater 1/

system transient, and the frequency of past feedwater sys_tern transients;-

the event raises serious safety questions regarding the safe operation of the Salem facility.

]./ Of primary. concern to the NRC is the AliolS (anticipated transient without scram) event initiated by a loss of feedwater transienta In 1981 and 1982, Salem 1 experienced about 11 and 5 feed transients, res~ectively, while Salem 2 experienced about 14 in 1981 and about 11 in 1982.

This results in a tot~l average of ab6ut 10.. transients per unit y~~r of operation for each unit.

III The ~nalysis of the event5 therefore, raised equipment issues, operationa1 issues and management issues which must be addressed to ensure safe future operation.

The licensee has agreed to take certain remedial actions prior to

• resumption of operation from the ~urrent outage, as well as certain 1onger-tenn acti'ons following restart.

Tliese remedial actions in-volve equipment i'ssuesp operational iss*ues*, and management i'ssues.

The equipment issues involve (1} s*afety classificati'on of breakers, (2) identification of cause of failure, (3} ~erificatton testin~ and (4) maintenance and surveillance procedures.

Tne operational issues involve (1) operating pro~edure fa~ reactor trips and anticipated transients without scram (ATWS}, (2l operator training and (3) operator response..

The management i'ssues i*nvolve ClJ overa11 management capability and performance, (.2) mast'er equi'pment listi (3) procurement procedures,

( 4) work-order procedures, (SJ post-trip revi'ew, (6 j timeliness of event

~otifi.cation, (71 updating vendor.,suppl i ed information, [8) involvement

. of QA personnel with other station departments, and (.9) post maintenance operab.i.1 i. ty testi'ng.

The NRC staff lias reviewed these propos-ed corrective actions and determined tliat 9 after* impl ementati*on, they wi 11 ensure the safe operation of the facility.

However, to ensure that pennanent corrective actions are in place, and to fncrease the relia5ilfty of the mitigati'on features of this parti.cular facility due to its liistory, certain other long-term actions are requtred in the interest of the public health and safety.

IV.

Accordingly, pursuant to Sections 103 5 16l(i) 5 and 182 of the Atomic Energy Act of 1954, as amended s and the Cammi ssi on 1 s regul ati ans in

• 10 CFR Parts 2 and 50 5.. IT IS HEREBY ORDERED THAT the licensee should show cause why it should not be required to:

Ae Within 60.days of the effective date of this Order, submit to the Director, Office of Nuclear Reactor Regulation, a detailed schedule for.accomplishing the following actions as soon as possible:

(1)

Implementing at the Salem facili_ty (Units 1 and 2) the following feature of the proposal by the* Industry Group _on AiWS submitted on April 23, 1982*, on Docket PRM-50-29 {page 10 of Appendix C): provision of automatic initiation of turbine trip and auxiliary feedwater independent of the reactor protection system; (2)

Providing at the Salem facility diversity in activating (tripping) the reactor from.breakers, for example, by incorporating the breaker shunt trip function into the automatic trip circuits of the-reactor* protection system;.

(3)

Developing and implementing procedures consistent with the applicable emergency response guidelines (letters from Jurgensen to* Eisenhut dated November 3o, 1981, from Kingsley to Eisenhut dated July 21, 1982, from Kingsley to Eisenhut dated January 4, 1983) for ATWS-type transients; and

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(4)

Training operators an~ advisory _personnel on the pro..

cedures dev~loped under section IV.A(3) prior to implementation.

The schedule shall be subject to approval by the Director and shall be implemented following such approval.

The Director may modify the approved schedule in writing for good causeo Bo Within 60 days of the date *of this Order, submit to the Director their plan and schedule to conduct an evaluation into the background, causes, and circumstances leading up to the events of February 22 and 25, 19830 The purpose of the evaluation shall be to develop a plan to further improve the management's role in identifying and directing resolution of problems associated with safety.. related equipment procurement, maintenance~ surveillance and operationse The scope of the eva1 uati oti wi 11 coyer all safety-related equi pnento The evaluation shall include a review of the methods used by managers to identify inter-departmental problems that may affect safetyerelated activitiese The evaluation shall also include an analysis of the effectiveness of existing independent safety review groups with specific examination of their roles in.. the identification of issues

• and recommendations related to problems associated with the reactor trip breakers.

The plan shall include the method for reporting the results of t~e evaluation to the Director, and the licensee's method for implementation of any recommendations resulting from the evaluat~on and/or.the NRC review of the evaluation report.

Upon approval by the Di rector, the pl an and schedule shal 1 be implemented.

• The Director may modify the approved*plan and schedule. in writing for good cause.

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Within 25 days of the date of this order, the lice"nsee may show cause why the acti ens described in Section IV spou1 d net be ordered by fi 1 i ng q written answer und~r oath or affinnation that sets forth the matters of fact and law on which the licensee relies.

As provided in 10 CFR 2.202(d),

the licensee may answer.by consenting to the order proposed in Section IV of this order to show cause.

Upon the licensee'~ consent, or upon failure of the licensee to answer this* order within the allotted time, the tenns of Section IV of this _order wi11 become effective. Alternatively, the licensee may request a hearing on this order within 25 days after= the issuance of.this order.

/Jtty request for* a hearing or answer to this order shall be submitted to the Director, Office o~ Nuclear.. Reactor Regulation, U.S. Nuclear Regulatory Commission, Washington, D. C.

20555.

A copy of the request or answer shall also be sent to the Executive Legal Director at the same address.

If a hearing is held on this order, the Commission will issue an order designating the-time and place of hearing.

If a hearing is held, the issue to be considered at such a hearing shall be whe~her tne licensee shall perfonn the actions specificed in Section IV of this order.

FOR THE NUCLEAR REGULATORY COMMISSION*

i Harold Re Denton, Director Office of Nuclear Reactor Regulation Dated at Bethesda, Maryland, this day cf March 1983.

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