ML20140G798

Forwards Review of Operating Experience for Startup.No Significant Problems Re Reactor Sys & Instrumentation Reported.Seven LERs Initiated Since Initial Criticality

ML20140G798
Person / Time
Site:	Palo Verde, 05000000
Issue date:	07/30/1985
From:	Kirsch D NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION V)
To:	Thompson H Office of Nuclear Reactor Regulation
Shared Package
ML20140B723	List: IR 05000528/1985012 ML20140B717 ML20140G753 ML20140G757 ML20140G762 ML20140G771 ML20140G781 ML20140G786 ML20140G795 ML20140G798 ML20140G803 ML20140G806 ML20140G809 ML20140G813 ML20140G818 ML20140G822 ML20140G828 ML20140G834 ML20140H569
References
FOIA-86-45 NUDOCS 8510010045
Download: ML20140G798 (20)

Text

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[ggS I'f Gy,*'e , UNITED STATES I

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- - .--as NUCLEAR REGULATORY COMMISSION l REGION V t,

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1450 MARIA LANE,SutTE 210 WALNUT CREEK, CALIFORNIA M5M July 30, 1985 MEMORANDUM FOR: Hugh L. Thompson, Director Division of Licensing, NRR ,

FROM: Dennis F. Kirsch,' Acting Director Division of Reactor Safety and Projects Region V ,-

SU3 JECT: REGION V INPUT TO ACRS REQUESTS ON PALO VERDE Encicsed as Attachment 1 is the review'of operating ' experience for the startup of Palo Verde Unit 1.

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D. F. Kirsch, Acting Director Division of Reactor Safety and Projects i

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J ATTACEMENT 1 l

Review of Startup Enperience for Palo Verde Unit 1 Region V undertook an enhanced inspection effort of initial criticality and Icv power testing by providing around-the-clock it<pection coverage of these activities. The Inspection Team's findings are summarized belev.

t Overall, the licensee's preparation for the implementation of initial startup activities was marked by unusual cautice and thoroushness.

Initial criticality was achieved at 0145 on May 25, 1985. Boron conceatration at initial. criticality was within approximately 11 ppm of that predicted, or approximately 0.1 percent reactivity worth. This compares favorably to similar facilities - particularly for a lead plant design.

1 No significant problems were experienced in the performance of reactor systems ,

and instrumentation. The licensee took steps, in response to observations by )

tne Inspection Tea =, to improve the working environment within the main  ;

.. control room (principally with regard to noise levels and effective communications) as well as the attentiveness of the control room operators.

Not withstanding the need fcr seme improvement in these areas, the overall

performance of the operating crews was good. A strong discipline was evident

] in the operating ste.ff's adherence to operating procedures.

i The presence and effectiveness of operational Quality Assurance personnel in their monitoring and surveillance of operational activities was particularly evident. Likewise, the presence of senior corporate, as well as site management and supervisory personnel, has been noteworthy, and their involvemen.t in day-to-day operational activities has been substantive and

effective.

' The licensee experienced several occurrences during the power ascension phase '

in Unit 1. These occurrences are described below.

1) Three different reactor trips. Two resulted from loss of feed flow and subsequent high pressurizer pressure trip. One resulted from an ,

inoperable CEAC causing a local power density and DNBR trip. '

i

2) Difficulty in identifying the source cf RCS leakage on two different occasions. Unidentified RCS leakage exceeded 1 GPM resu* ting in plant shutdown per Technical Specification requirements.

3) Broken condenser baffle causing two leaking tubes and damage of insulation. This resulted in an extended shutdown period for repair.

These operational events were handled in a conservative and responsible manner 1 l

by the licensee. The number of trips that occurred was not excessive and resulted from anticipated events.

l I 1

..:..-. . . - - - . . - . . . . . . .. . .; . . ...:. , . ..c. ; . - . .

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- 2-Seven LER's to date have been initiated by the licensee since initial criticality.

. Finally, Region V identified one inoperable aspect of the post-accident sacpling system (PASS). The portion devoted to sampling containment atmosphere was found to be inoperable due to licensee calculations showing prohibitively high radiation levels in the sample area after an accident.

Prior to licensing, the licensee had informed the Commission that PASS was operable. The licensee is currently taking steps to correct this deficiency.

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'i i LOSS OF LOAD EVENT 1

1. Selected vugraphs from Staff meetings

2. Staff's letter of October 2,1985

3. Region V CAL of September 20, 1985 I

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... . . - - . . . - . . . .. : - - J - - --- -- '~~^~~^~

CONDITIONS PRIOR TO EVENT OF 9-17-85 -

1. REACTOR AT 53% FULL POWER

2. TURBINE GENERATOR ONLINE AT 585 MWE

3. PREPARING FOR 50% LOSS OF LOAD TEST PURPOSE OF 50% LOSS OF LOAD TEST:

1. DEMONSTRATE THAT THE PLANT CAN ACCOMMODATE A LOAD REJECTION FROM 50% POWER 2.,. VERIFY THAT THE TRANSIENT DID NOT IlllTIATE A REACTOR POWER CUTBACK 11-1

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l SEQUENCE OF EVENTS 2208 TEST INITIATED BY REMOTE MANUAL OPENING OF BOTH GENERATOR OUTPUT BREAKERS. (TURBINE-GENERATOR FLUCTUATIONS) 2209 REACTOR TRIP (FLOW-PROJECTED DNBR TRIP FROM CPC) 2209 TUR3INE TRIP (CAUSED BY REACTOR TRIP) 2215 NON-SAFETY RELATED AUXILIARY FEEDWATER PLMP STARTED 2217 ATMOSPHERIC DUMP VALVES (ONE ON EACH-STEAM GENERATOR)

OPENED 3%

2218 MAIN STEAMLINE DRAINS AUTOMATICALLY REOPENED UPON -

~

RESTORATION ON NON-1E ELECTRICAL POWER 2222 SIAS AND CIAS INITIATED (1837 PSIA; 540 U F)

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'SIAS AND CIAS ACTUATIONS WERE VERIFIED AS PER DESIGN  !

WITH HPSI INJECTING APPROXIMATELY 75 GPM TO EACH COLD -

LEG 2223 NOTIFICATION OF UNUSUAL EVENT DECLARED DUE TO COMPLICATED REACTOR TRIP AND INITIATION OF A SIAS 2225 AUXILIARY OPERATOR RE-ENERGIZED MOTOR CONTROL CENTER NHN-M-72 UNDER CONTROL ROOM DIRECTION (RE-ENERGIZED-CHN UV-501, VCT OUTLET AND UV-536, RWT HIGH SLCTION TO CHARGING PUMPS.)

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5 SEQUENCE OF EVENTS (CONT.)

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2237 CHARGING HEADER LOW FLOW ALARM (40 GPM)

INTERMITTANT CHARGING HEADER PRESSURE ALARMS

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i FOR THE NEXT 43 MINUTES, OPERATORS WERE -

ATTEMPTING TO REESTABLISH CHARGING PUMP SUCTION FROM:

(1) RWT HIGH SUCTION VIA CH UV 536 ,

(2) RWT LOW SUCTION VIA CHN V 327 (3) RWT HIGH SUCTION VIA UV 532 -- BAMP CH 514 TO THE CHARGING PUt3PS (AFTER NON-1E POWER RESTORATION) 2320 REESTABLISHED CHARGING' FLOW WITH TWO CHARGING PN'PSINJECTING44GPMTORCS 2358 RESET SIAS AND CIAS QCS PRESSURE AND INVENTORY STABLE AND UNDER CONTROL) 0102 9/13/85 TERMINATION OF NOTIFICATION OF tt1 USUAL EVENT i

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SCOPE OF AUXIIIARY PRESSURIZER SPRAY SYSTEM -

o AUXILIARY PRESSURIZER SPRAY SYSTEM BEGINS AT BRANCH FROM CHARGING SYSTEM AND ENDS AT PRESSURIZER SPRAY N0ZZLES o MECHANICAL COMPONENTS C0HSIST OF:

PIPING TWO SOLEN 0ID JPERATED VALVES (CH-203 & CH-205)

CHECK VALVE o

' SCHEMATIC 0F AUXILIARY PRESSURIZER SPRAY SYSTEM AND SOURCES OF B0 RATED WATER (VIA CHARGING SYSTEM)

SHOWN IN: .

FIGURE 2 1-4 0F CEN-239, AND FIGURES 5 & 6 0F APPENDIX B IN NUREG-1044

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J STEAM GENERATUR TUBE RUPTURE (SGTR) ANALYSES o

ORIGINAL ANALYSIS INCLUDED IN CESSAR-F (TENDERED IN I

1978):

BASED ON CATEGORIZATION MATRIX OF CHAPTER 15 (IN ACCORDANCE WITH REG. GUIDE 1 70, REV.2)

TUBE RUPTURE ONLY AUXILIARY PRESSURIZER SPRAY WAS NOT CREDITED FOR ANALYSIS TO CALCULATE OFFSITE DOSES o

ANALYSIS REVISED TO BE CONSISTENT WITH STANDARD REVIEW PLANS (1981/1982):

} SGTR WITH AND WITHOUT LOSS OF 0FFSITE POWER AUXILIARY PRESSURIZER SPRAY WAS NOT CREDITED FOR ANALYSIS TO CALCULATE OFFSITE DOSES CREDIT WAS TAKEN FOR THREE SECOND TIME DELAY BETWEEN REACTOR TRIP AND LOSS OF 0FFSITE POWER o

NRC STAFF REQUIRED RE-ANALYSIS WITH ADDED SINGLE FAILURE AND RECOGNITION OF EMERGENCY OPERATING

, PROCEDURES PER CEN-152 (APRIL 1983)

! o SEPARATE ANALYSES WERE PERFORMED FOR CESSAR AND PALO VERDE (1984). BOTH ANALYSES RECOGNIZED USE OF AUXILIARY PRESSURIZER SPRAY (AS AN OPERATOR ACTION) o NEW PALO VERDE ANALYSIS IS BEING PERFORMED, WHICH DOES NOT USE AUXILIARY PRESSURIZER SPRAY IN THE FIRST TWO HOURS

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'. SIAS 581 AFF OVERPIDE 655

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AUX SPRAY 1015/7200 115 115 TUBES c,) gy

.. REC 0VEPED 1385/1347 182 186 7

2 HP DOSE a EAB 7200 200 208 9

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OPERATOR CONTROLS AUXILIARY SPRAYFLOW, Q fBACKUPPRESSURIZERHEATEROUTPUT,AND 5 i HPSI FLOW IN ORDER TO KEEP THE RCS 20cp

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Palo Verde Nuclear Geweating Station FSAR STEAM GENERATOR TUBE RUPWRE WITH IDSS OF OFFSITE PCWER AND A FULLY STUCK

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EMERGENCY OPERATING PROCEDURES ADVISE OPERATOR OF AVAILABILITY OF VENT TO BACKUP PRESSURIZER AUXILIARY SPRAY e

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CVCS ENHANCEMENT t

o REPORT OF ACTIONS UNDERTAKEN TO ADDRESS SEPTEMBER 12, 1985 EVENT C PER SEPTEMBER 20, 1985 MEETING )

o THREE MODIFICATIONS PLANNED ENSURE CONTINUED CONTROL OF V501 AND V536 FOLLOWING LOP AND SIAS 4

4 ADD SECOND, DIVERSE REFERENCE LEG FOR VCT LEVEL MONITORING WITH ALARM

- AUTOMATIC REALIGNMENT OF V501 AND V536 p

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ONE WET AND ONE DRY LEG TO PROVIDE DIVERSE REFERENCE ,

COMPARATOR ALARM PROVIDES INDICATION OF POSSIBLE LOSS Oc  !

CORRECT REFERENCE TO ONE OF THE TRANSMITTERS 1

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~ UNITED STATES l' j NUCLEAR REGULATORY COMMISSION

, a wAsmucion, o. c. zosss i

(- ,

/ OCT 2 198 5 l Docket Nos.: 50-528, 50-529, j and 50-530 t

i Mr. 'E. E. Van Brunt, Jr. -

Executive Vice President

Arizona Nuclear Power Project i

Post Office Box 52034 l Phoenix, Arizona 85072-2034

Dear Mr. Van Brunt:

On September 12, 1985, Arizona Nuclear Power Project (ANPP) conducted a t

less-of-load test on Palo Verde Nuclear Generating Station Unit 1 from i

approximately 55% powar. The plant did not perfonn as expected. The test resulted in an event involving loss of all offsite power to non-essential loads (including the reactor coolant pumps), turbine trip and reactor trip.

j During the recovery phase of the event, overcooling of the reactor coolant system (RCS) occurred to the extent that the emergency core cooling systems

! were automatically initiated, followed by the associated automatic initiation l of containment isolation.

3 The following two sequences occurred during the event that caused the loss of all three charging pumps:

(1) When the safety injection actuation signal (SIAS) occurred, power to certain suction valves for the charging pumps was lost since the motor control center for these valves was classified as non-essential and, accordingly was designed to be automatically shed from the safety related

, electric buses.

(2) Because of a malfunction of the single water level instrument channel

, for the volume control tank (VCT), automatic control action was lost which would have transferred the section of the charging pumps from the VCT to other water sources. Also, after the containment isolation signal was received, all makeup flow to VCT was isolated.

Due to the above sequences, the VCT emptied, the charging pumps became bound on VCT hydrogen cover gas and the pumps were tripped. This produced a potentially hazardous situation when, to re-establish charging pump flow, the lines from the pumps were vented to remove gas.

One of the charging pumps is required to provide auxiliary spray to the pressurizer.

' In addition, the charging system may be needed to satisfy General Design Criteria (GDC) 26 and 33. To assure that specified acceptable fuel design limits are not exceeded, (1) GDC 26 requires that the plant design include a redundant reactivity control system (e.g., baron addition) and (2) e w -n p > w ~ l

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GDC 33 requires that a system be provided to supply reactor coolant makeup for protection against small breaks in the reactor coolant pressure boundary (i.e., when the reactor coolant system is at operating pressure).

As a result of this event, the Region V Office of the NRC issued a Confirmatory Action Letter, dated September 17, 1985, confirming an ANPP comitment not to restart Palo Verde Unit 1 until the issue of appropriate design criteria for the auxiliary spray system was resolved to the satisfaction of the NRC staff.

Your letter of September 18, 1985 discussed the September 17,1985 event and briefly addressed concerns relating to the auxiliary spray system. At a meeting on September 20, 1985, your staff provided a more indepth discussion of the events at.d further discussed the auxiliary spray system.

At the conclusion of the September 20, 1985 meeting, ANPP comitted to certain additional short term compensatory measures which justified continued operation of the facility while the lor-3 tem corrective actions were developed. The staff found these compensatory measures sufficient to allow restart of Palo Verde Unit 1 pending the resolution of the design criteria issue for the auxiliary spr,sy' system. On the basis of your comitments to the agreed to compensatory measures, the Region V Office of the NRC issued a followup Confirmatory Action Letter, dated September 20, 1985, deteribing the comitments and stating that adequate short term compensatory measures are in place for restart of Palo Verde Unit 1. The letter also stated that long tenn measures to assure the reliability of the auxiliary spray system would be the subject

{ of future correspondence.

In a November 3,1982 letter, you stated that the safety-gradr . xiliary spray system provides a depressurization capability of the primary system when the 4

reactor coolant pumps are not running. In a July 28, 1983 letter, you stated i

that the safety grade auxiliary spray system is used to depressurize the plant to shutdown cooling entry conditions following a steam generator tube rupture (SGTR) accident without exceeding offsite dose limits. As discussed in NUREG-1044, " Evaluation of the Need for a Rapid Depressurization Capability  ;

, for Combustion Engineering Plants", the staff's acceptance of the auxiliary spray system in lieu of PORVs was based on its understanding that the auxiliary

spray system was safety grade.

8ecause of the above considerations, we are concerned about the pressurizer auxiliary spray system for the following reasons and are requesting additional information as discussed in the enclosure:

(1) The degree to which the design, installation and operational capabilities of the auxiliary spray system meets its licensing basis.

1 (2) The-Palo Verde accident analyses, in particular the SGTR analysis, takes credit for the auxiliary spray system.

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(3) The Palo Verde plant design also relies on the auxiliary spray system '

as a means of rapid depressurization of the primary system under '

"; certain accident scenarios since the plant does not include PORVs.

Staff evaluation on the need for PORVs in the CE System 80 design

} was based on the understanding that a safety grade auxiliary spray  !

.- ' system would be part of the design. In order for the staff's ~

conclusion to remain valid, we require that the auxiliary spray system be highly reliable. Our original review equated this high reliability

• l with meeting safety grade requirements.

, (4) The September 12, 1985 event demonstrated the operators' concern with '

i getticg the charging pumps operable. ,

) Pursuant to 10 CFR 50.54(f), you are requested to furnish in writing, under cath or affirmation within 20 days of the date of this letter, your plans, program and schedule to bring.the auxiliary spray system into conformance with i the plant's licensing basis. Your submittal should address the resolution of '

the concerns identified above and respond to the specific questions in the enclosure. If you desire, we are prepared to meet with you to discuss your 1.

response when it is sufficiently developed to make such a meeting useful. .

Sincerely, ,

M -

H h L. Thomgan . rector Di sion of Licensin .

Office of Nuclear Reactor Regulation t j

Enclosure:

As stated cc: See next page 9

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ENCLOSURE ,

t 2:00C57 FOR ADDITIONAL INFORMATION CONCERNING THE SEPTEMBER 12, 1985 EVENT AT PALO VERDE UNIT 1 i j

1. The Palo Verde design includes a safety grade auxiliary. pressurizer spray sys tem. As a result of the September 12, 1985 event at Palo Verde Unit 1, it is our view that the auxiliary pressurizer spray system does not meet safety grade standards and that the Palo Verde design is not consistent with the docketed information describing the system design. -

Therefore, describe the design modifications you intend to make to

upgrade the auxiliary spray system to safety grade standards and provide the schedule by which this effort will be accomplished. A justification i

for operation until the modifications have been completed should be '

I provided.

2. The auxiliary spray system was stated to be safety grade on the Palo

, Verde docket and then later determined to have single failure i

i vulnerabilities and other deficiencies. Provide a detailed explanation of how the QA process, which should include an independent review and i verification of design adequacy, did not detect these deficiencies in the

auxiliary spray system. Also provide a description of the corrective 1

i actions you intend to take to remedy any weaknesses identified in the OA process.

3. Provide a detailed description of what you consider to be safety grad?

j l design requirements and how you apply these requirements to systems and i i components that are specified as safety related. In particular.. discuss how these requirements were applied to the auxiliary spray system and j

whether the identified deficiencies in auxiliary spray system were due to j a failure to apply them to the system, i 1

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O o UNITED STATES

,# g y c g NUCLEAR REGULATORY COMMISslON

r. -

y REGION Y 1460 MAtlla 1.4Ns.StJITE 210

[ gg WAl. NUT CREsK. cALIPORNIA 940e8 SEP 2 01985

.. .- . .. . Docket .No. 50-528 CONFIRMATORY ACTION LETTER _

License No. NPF-41 Arizona Nuclear Power Prnject .

Post office Box 52034 Phoenix, Arizona 85072-2034 Attention: Mr. E. E. Van Brunt, Jr.

Executive Vice President SIAbj ect: Katurn of Palo Verde 1 to I'ower Operations from Current Outage Centlemen:

In my letter to you of September 17, 1985 I confirmed Arizona Nuclear Power Project's (ANFP) agreement that prior to restart of the Unit from its current shutdown, you would ensure that the issue of apfropriate design criteria for the auxiliary spray system was resolved to the satisfaction of the NRC staff.

By letter dated September 18, 1985, you discussed the unscheduled shutdown.cf September 12, 1985 and briefly addressed NRC concerns relating to the a=N=7 ,

spray system and interfacing equipment. In response to these concerns, you

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proposed certain short term compensatory measures for continued operation.of. - .

the facility. .

t In a meeting with the NEC staff on September 20, 1985, you provided a more in-depth description of the September 12, 1985 event, including the sequence of .

evento, design characteristics of the auxiliary spray system, and a further discussion of the short term compensatory measures fo.! continued operation. __

At the conclusion of the meeting, Mr. J. Haynes. Vice President for Nuclear Production. ANFP, committed to the following short term compensatory measures: <

(1) Monitor the reference leg of the volume control tack level indicator on a daily basis. If the data obtained justify a less frequent monitoring '

interval, ANPP may propces a different interval to the NRC staff, .

(2) Revise the appropriate procedures to require alignment of the refueling l water tank to charging puzsp suction promptly on loss of offsite p. wor., l (3) Institute procedural cautiotie on restart of the charging pumps.

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- 2-(4) Examine the post-trip review process in light of the September 12, 1985 event to assure that off-normal events are adequately evaluated.

particularly with respect to their potential safety significance.

(5) Fn=f ne the .procese for vendor reviews of the remaining power ascension tests to assure that, for equipment particularly sens4tive to the test J

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being conducted, appropriata vendor input has been provided in the test . .

development.

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(6) Review the shif t complesant for the remaining power ascension tests to .

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determine if addicianal staffing may be approprista. .,

On the basis of the above cosasituents, we are satisfied that adequate short-term compensatory measures are in place for restart of the Unit from its current shutdown. Long term measures to assure the continued reliability of the _

auxiliary spray system will be the subject of futura correspondence.

If our understanding concerning the above measures is not correct, you should .

. promptly notify this office in writing. ,

J. 3. Martin Regional Administrator Distribution:

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1 LOSS OF OFFSITE POWER EVENT

1. Vugraph from Staff meeting

2. Preliminary Notification flotice of Switchyard Distribution Malfunction (PNO-V-85-69) dated October 8,1985

PALO VERDE LOSS OF 0FFSITE POWER

• OCTOBER 3, 1985 (J. T. BEARD, NRR)

PROBLEM SIMULTANEOUS LOSS OF BOTH OFFSITE POWER CIRCUITS CAUSING PLANT TRIP LOSS OF SWITCHYARD INSTRUMENTATION LOSS OF CONTROL ROOM OPERATION OF SWITCHYARD BREAKERS SIGNIFICANCE ,

EVENT MAY HAVE BEEN CAUSED BY MALFUNCTION OF A SINGLE COMMON MULTIPLEXING MONITOR SYSTEM; STILL UNDER INVESTIGATION CIRCUMSTANCES PLANT AT 82% POWER IN ABNORMAL ELECTRIC POWER CONFIGURATION (NO LOADS ON AUX, TRANSFORMER)

SIMULTANEOUS LOSS OF BOTH S/U TRANSFORMERS EDGS AUTO STARTED, LOADED PLANT TRIP ON LOSS OF RCPs -- L0 DNBR PROJECTION

• AFW AUTO STARTED, MAINTAINED PROPER S/G LEVEL SWITCHYARD MULTIPLEXER LOST: CAUSED LOSS OF INDICATIONS AND REMOTE CONTROL OFFSITE POWER RESTORED LOCALLY IN 24 MINUTES RE-START OF RCPs DELAYED BY RCP MOTOR LOCK 0UTS ON MAIN GENERATOR COASTDOWN.

FOLLOW-UP UTILITY STILL EVALUATING NRR/0RAB MONITORING l

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PR.ELIMINARY N_0TIFICATION OF E7DiT CR UNUSUAL OCCU13.ENCE--F)io-7-85-69 Date: 10/08/65 This preliminary notifiestion cons titutes ZARLY notice of POSSIBLE saf ety

or public interest significance. The information presented is se initially I

received without verification or evaluation and is basically all that is kncvn by Ze31on, V =tsf f on thi.s. ::ste.-

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A0Vce- y ton FACILITT: Arizona Nuc1VA;M wer Pgo),enigEnergency Classificatica Pale Verde Unit 1 '-I Notification of Unusual Event Docket Nos. SCd 2'Sj=q-

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Site Area E=crgency Ceneral Ibergency

' Not Applicable SU3IECT: SWITCETARDELECTRICALDISTRIEUidGNMALFURCIION (FNO-V-85-68 UFDATE) '- .

Follevins the Cetober 3 loss of nortal electric power the licensee initiated i i en investigation to determine the cause of the opening of the normal feeder

brenkers to the 13.8 KV busses (505 and 505), located in the plant switchyard.

Troubleshooting identified several probic=s associated vich the plant

=ultiplener which prevides centrol and indication of the above breakers fron the Centrol Koc=, On October 8 at 7:58 PM, vtth the plant in Hot Standby, a repeat less of scr=al electric pcver vas experienced shortly af ter replacing a

=iereprocescor card in the Lcesi Multiplexer Ter=inel. A reacter trip

, ec urred (sbutde.u banir-s were withdra a before the trip) f alle.iing the los's of

reacter ceolant purps. The diecel generators started and

:t.pplied the

esacntial busses. An Ucumual Event was declared at 8

03 P. , and was ter:inated at S:41 pM fo11cving resecration of ferced circulatics and stable plant cceditions. The licensee is currently proceeding with a design change to hard-wire centrol for the SOS s :d Sc6 nor=al and alternate feeder breakers in lieu ef the existing =ultipicxer syste=. In the interi=, the :.:ltiplexer has been disec:nected fren the trip coil fuc : h 505 end SC6 nornal feeder b re akers and alterna t e f eede r bren*<.ars. The p.esident Inspector respe;ded to

• the Occcher a event and centinues to =onitor the licensee activities including l restart criteria. The licensee notified local'=edia upec decisration cf the Unusual E.ent.

This infor=stien la current as of 2:00 PM (EST) Octeber 8 1985.

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