ML20148E943

Notice of Violation from Insp on 880111-15.Violations Noted: Unit 2 Entered Mode 5 Exceeding by Approx 96 Hrs Time Required to Shutdown

ML20148E943
Person / Time
Site:	Catawba
Issue date:	03/14/1988
From:	Grace J NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II)
To:
Shared Package
ML20148E932	List: ML20148E926 ML20148E943
References
50-413-88-06, 50-413-88-6, 50-414-88-06, 50-414-88-6, NUDOCS 8803280033
Download: ML20148E943 (22)

Text

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i e ENCLOSURE 1 NOTICE OF VIOLATION Duke Power Company Docket Nos. 50-413, 50-414 Catawba Units 1 and 2 License Nos. NPF-35, NPF-52 During the Nuclear Regulatory Commission (NRC) inspection conducted on January 11-15, 1988, a violation of NRC requirements was identified. In accordance with the "General Statement of Policy and Procedure for NRC Enforcement Actions," 10 CFR Part 2, Appendix C (1986), the violation is listed below:

Technical Specification 3.7.4 requires at least two independent nuclear service water loops be operable in Modes 1, 2, 3 and 4. With only one nuclear service water loop operable, restore at least two loops to operable status withiri 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> or be in at least hot standby within the next six hours in cold shutdown within the following 30 hours3.472222e-4 days <br />0.00833 hours <br />4.960317e-5 weeks <br />1.1415e-5 months <br />.

Contrary to the above, on August 30, 1986, at 8:30 p.m. with Unit I shutdown for refueling and Unit 2 in Mode 1, Power Operation, Nuclear Service Water Train A was made inoperable with respect to Unit 2. On September 8, 1986 at 4:40 a.m., Unit 2 entered Mode 5, thus exceeding by approximately 92 hours0.00106 days <br />0.0256 hours <br />1.521164e-4 weeks <br />3.5006e-5 months <br /> the time required to shutdown to Mode 5.

This is a Severity Level IV violation (Supplement I).

Pursuant to the provisions of 10 CFR 2.201, Duke Power Company is hereby required to submit a written statement or explanation to the Nuclear Regulatory Commission, ATTN: Document Control Desk, Washington, DC 20555, with a copy to the Regional Administrator, Region II, and a copy to the NRC Resident Inspec-tor, Catawba, within 30 days of the date of the letter transmitting this Notice. This reply should be clearly marked as a "Reply to a Notice of  ;

Violation" and should include [for each violation]: (1) admission or denial of the violation, (2) the reason for the violation if admitted, (3) the corrective steps which have been taken and the results achieved, (4) the corrective steps which will be taken to avoid further violations, and (5) the date when full compliance will be achieved. Where good cause is shown, consideration will be given to extending the response time. If an adequate reply is not received within the time specified in this Notice, an order may be issued to show cause why the license should not be modified, suspended, or revoked or why such other  ;

action as may be proper should not be taken.

FOR THE NUCLEAR REGULATORY COMMISSION ORIGINAL SIGNED BY

&$utd J. Nelson Grace Regional Administrator Dated at Atlanta, Georgia this/%dayofMarch1988

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, MAR 141988 "

ENCLOSURE 2 ENFORCEMENT CONFERENCE

SUMMARY

On February 23, 1988, representatives of the Duke-Power Company (DPC) met with the NRC at the NRC's request in the Region II office in Atlanta, Georgia. The subjects of discussion were operability and reportability of several potential unanalyzed conditions in the Catawba Nuclear Service Water (RN) system. The list of conference attendees is contained in Attachment 1.

Following opening remarks given by M. L. Ernst, NRC Region II and H. Tucker, DPC, DPC gave a presentation which addressed the specific concerns of the NRC.

The presentation consisted of a review of RN system design features, a review of the various RN configurations of concern, safety significance, operability /

reportability decision points and corrective action.

The outline of the DPC presentation is contained in Attachment 2.

All NRC concerns on this issue were addressed in the meeting. ~It was evident that significant preparation time was expended. OPC also stated that as a result of this issue their sensitivity to reportability had been increased.

The NRC enforcement action concerning this issue is discussed in Enclosure 1.

Attachments:

1. List of Attendees at the Catawba Enforcement Conference

2. Catawba Nuclear Station Nuclear Service Water System Region II Presentation 1

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MAR 141988 ATTACHMENT 1 ENFORCEMENT CONFERENCE DPC - CATAWBA ATTENDEES NRC M. L. Ernst, Deputy Regional Administrator L. A. Reyes, Director, Division of Reactor Projects (DRP)

V. L. Brownlee, Branch Chief, DRP T. A. Peebles, Section Chief, DRP P. K. Van Doorn, Senior Resident Inspector, DRP B. R. Bonser, Project Engineer, DRP C. A. Julian, Branch Chief, Division of Reactor Safety (DRS)

R. H. Bernhard, Reactor Inspector, DRS M. Thomas, Reactor Inspector, DRS G. A. Belisle, Section Chief, DRS A. F. Gibson, Director, DRS B. Uryc, Enforcement Coordinator G. R. Jenkins, Director, Enforcement and Investigation Coordination Staff G. Lainas, Assistant Director, NRR K. Jabbour, Project Manager, NRR J. D. Smith, Operations Inspector, NRR W. T. LeFave, Engineer Plant Systems, NRR H. Wong, Senior Enforcement Specialist, OE F. Hawkins, Section Chief, NRR Duke Power Company H. B. Tucker, Vice President, Nuclear Production N. Rutherford, Manager Licensing J. W. Hampton, Manager Catawba Nuclear Station (CNS) i T. B. Owen, Assistant Manager CNS i L. Hartzell, Compliance Engineer, CNS H. B. Barron, Operations Superintendent, CNS P. G. LeRoy, Licensing Engineer, CNS

R. D. Sharpe, Nuclear Engineer, DPC

E. W. Fritz, Design Engineer, DPC Design D. W. Eaves, Design Engineer, DPC Design t

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O O WAR 1 4 888 ATTACHMEf4T 2 l l-i CATAWBA NUCLEAR 8TATOON NUCLEAR SERVOCE WATER SYSTEM i

REGOOM 00 PRESENTATION FEBRUARY 28,1988 I<

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. MAR 141988 CATAISA NUCLEAR STAT!0N NUCLEAR SERY!CE IdATER SYSTEM Sn5w.

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0/G #I II Cosponent N ESS Essential CooHng Liquid Header Wasta Containment Spray gg, l Control Roon l Cooling l Assured Aux 528 28 l Feedwater E55 l 2A ESS n i r <r ,, <r 57A 8438 54A 538

1. 2 63A 588 N ESS 2A 1A 18 28 0/G 0/G 0/G 0/G SNSW SNSW I

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CATAWBA NUCLEAR STATION NUCLEAR SERVICE WATER SYSTEM DE8IGN FEATURES EACH OF 2 LOOP 818 8 HARED BY BOTH UNIT 8.

EACH PUMP HA8 THE CAPACITY TO EITHER:

1. REMOVE COMBINED BLACK 0UT AND LOCA HEAT FROM ONE UNIT OR ,

2. REMOVE COMBINED BLACK 0UT AND C00LDOWN HEAT FOLLOWING TRIP FROM 100X FULL POWER.  !

i LOOP ISOLATION OCCUR 8 ON COMBINED LOCA AND I LOSS OF LAKE WYLIE.

NON-ESSENTIAL EQUIP 9EENT 18180 LATED ON LOCA SIGNAL - Sp.

d AUTOMATIC TRANSFER FROM LAKE WYLIE TO SN8WP ON .

EITHER 8p OR LOS8 OF LAKE WYLIE.

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. MAR 141988 DECEMBER 1985 - SHARED ASPECTS OF RN RECOGN0 ZED

- SITE AND D0!81GN ENGINEERING EVALUAYLON CONDUCTED.

Unrestricted operating req'sirements were clear; issue addressed was proper handling of out-of-service equipment.

- SHORT AND EXTENDED (> 72 HR)

IN0PERABILITY ADDRESSED. I After 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />, at least one unit is placed in cold shutdown with equipment isolated.

- LICENSE BASIS HEAT LOADS AND ACTUAL FLOW TEST DATA UTILIZED.

No special analysis involved.

- RE8IDENT INSPECTOR 8 BRIEFED.

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- LER 414/88-31-1 ISSUED 8-29-88.

LER was a direct result of RN operating practices; otherwise event was not reportable.

O O uAR 141988 AUGUST 1988 - REQUOREMENTS FOR TWO TRAIN 8 0F RN WOTH DIESEL GENERATOR INOPERABLE CONFLOCT WOTH CPERATONG UNIT ,

REQUIREMENTS.

- FSAR DID NOT ADDRESS REQUIREMENT 8 WITH ONE UNIT ON COLD BHUTDOWN. i FSAR defined two pumps as necessary if both units are operating:

second pump needed to place non-LOCA unit cold shutdown.

- DESIGN ANALYSIS PERFORMED FOR CYCLE SPECIFIC FLOW REQUIREMENT.

l FSAR values used for LOCA (operating) unit requirements; refueling unit requirements took into account time since shutdown. Plant test confirmed system flow performance. l

- DESIGN STUDY s88 INITIATED TO  !

DETERMINE GENERIC FLOW REQUIREMENT, Needed for future refueling outage work sequencing.

- RESIDENT INSPECTORS BROEFED.

- DESIGN ANALYSIS ADDRESSED EMERGENCY POWER SCURCE RATHER THAN FLC'.? PATH.

Closed valve IRN47A rather than IRN48B when IA D/G was out-of-service.

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MAR 141988 JANUARY 1987 - lDENTIFIED UNNECES8ARY FAILURE SCENARIO WITH SNSWP TRANSFER.

- CNPR02350 INITIATED DESIGN STUDYe80 TO EVALUATE DELETION OF RN TRANSFER ON Sp CONSIDERING:

1- PROBLEM DEFINITION '

2- ADEQUACY OF RESOLUTION 3- ALTERNATE RESOLUTION 8 4- F8AR IMPACT FROM RESOLUTION

- DESIGN STUDY 880:

1- AGREED WITH PROBLEM DEFMTION 2- FOUND FAULT WITH RESOLUTION 3- lDENTIFIED PRE-ALIGNMENT AS  ;

ALTERNATE RESOLUTION l 4- IDENTIFIED INCON818TANCY OF  !

RESOLUTION WITH F8AR  ;

- PRA INDEPENDENTLY REACHED CONCLUSION TO DELETE Sp INTERLOCK.

- NOT CURRENT OR FUTURE 8AFETY CONCERN.  ;

- REEDENT IN8PECTORS BMEFED.

- REPORTABILITY EVALUATED BY DUKE 8% 3R COMPANY.

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O O ug u a JULY 1987 - NRC AUDOT . TEAM MEMBERS EXPRESSED CONCERN WITH RN SYSTEM D280GN.

- REPORTABILITY ONLY GPEclFIC CONCERN AT EXIT.

Material needed to be taken back to NRC for further analysis.

- 30.549 LETTER 8-7-87 REQUESTED INFORMA710N.

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lo k o e th r t n. ide Tech Spec bases.

- RESPONSE AND MEETING WITH NRC 8-27-87 DESCRIBED PROCEDURES.

INFORMA710N FROM LER 414/88-31-1.

ANALYSIS OF SCENARIO QU73lDE LICENSONG SA818.

Analysis performed in response to apparent concern, not to justify previous or future operation.

- NRC CONCURRED WITH PROCEDURE 4, REQUESTED INCLUSION IN TECH SPEC.

- COURTE8Y REPORT PREPARED,PREViCUS ALIGNMENT ERROR IDEN70FDED DURDNG FINAL REVIEW (10-12-87)- REPORT GUBMlTTED A8 TECH SPEC VOCLA7dSN.

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l MAR 141988 FEBRUARY 1988 - CURRENT STATUS OF 088UE8

. - REVISED LOCA DECAY HEAT LOADS. .

- DESIGN STUDY 888 RESOLVED:

- LOCA AND SHUTDOWN COOLING REQUIMSEENTS EQUAL (5200 GPM RN TO KC).

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- DESIGN STUDY 880 RESOLVED:

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- POST-LOCA SEISMIC REQUIREMENTS FOR 8N8WP CLARRED,8p RN TRANSFER DELETED.

- F8AR AND TECH 8PEC CHANGE 8 8UBMITTED. l 1

- PIT LEVEL INSTRUMENT MODIFICATION PLANNED.

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- ACCIDENT acENANO MOUOMO LOCA,LC28 CF 07F4072 POWER AND GPECIFiC FA0 LURE OF ONE VALVE. l

- EXISTING PLANT AENORMAL PROCEDURE TO ADDRECS SPECIFIC POSTULATED FA0 LURE DIRECTED CPERATOR TO PERFORM CORRECT AC700N FOR RECOVERY.

- APPROXIMATELY 40 MINUTES YiOULD BE AVA0LABLE TO PERFORM THE CORRECTIVE ACTION.

Only minimum cooltug is required until transfer to containment sump recirculation.

- NO PUMP DAMAGE WOULD MAVE CCCURRED PRIOR 70 PERFORMING THE CORRECTIVE ACTION.

Non-essential flow demand is equivalent to containment spray cooling which is not established until transfer to sump.

- UNIT 2 TfA8 SUBCRITICAL 72 NCURS P0"R 70 EXc.EEt0NIJ THE 70ME ALLOWED TO ENTER CCLD 2:NU700'XN.

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- DECAY HEAT EXTREMELY LOW DUE 70 Lif GUM @.

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O MAR 14 888 CONCLUS00NS

- DUKE POWER COMPANY PERSONNEL WERE PROACTOWE IN EVALUATING RN SYSTEM OPERATION.

- THE RN SYSTEM WAS AT ALL TOME 8 OPERATED ON A MANNER CONSISTANT WITH THE FSAR.

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- THE RN SYSTEM WA8 AT ALL TOMES ABLE 70 i' PERFORM 178 INTENDED FUNCTION, I

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OPERABILITY /REPORTABILITY DECOSOON P00NTS TlHE FRAME TOPIC MAY 1988 RN EQUIPMENT / FLOW PATH 8 TO MEET T/8 (2 OPERABLE LOOP 8) FOR 2 UNIT MODE 1-4 OPERATION PUT IN T/8 INTERPRETATION FORMA 7.

ADDRESSE8 SINGLE FAILURE CRITERIA.

AUG 1988 LER IS8UED ON RN OPERABILITY, DESCRIBE 8 SHARED A8PECT OF SYSTEM AND REQUIRED ACTION 8 FOR OPERABILITY.

"lF A D/G 18 INOPERABLE,THE DEPENDENT RN TRAIN 18 CONSERVATIVELY DECLARED INOPERABLE ON BOTH UNIT 8 DUE TO THE 8 HARED NATURE OF THE RN SYSTEM"... .

" 0PERATION WITH LESS THAN 4 RN PUMP 8, REQUIRE 8- RN SYSTEM REALIGNMENT- TO EN8URE SUFFICIENT POST ACCIDENT FLOW IN THE EVENT ,

OF ANY 8 INGLE FAILURE."

OCT 1988 INITIAL DETERMINATION OF RN FLOW REQUIREMENT 8 WITH DIE 8EL OUT OF SERVICE.

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JAM 1987 POTENTIAL FOR PIT VALVE FAILURE I IDENTIFIED.TO DETERMINE IF BOUNDED BY ACCIDENT ANALYSIS. 4 MAR 1987 RN SNSWP SWAPOVER DESIGN STUDY,PART 1 DETERMINES PREVIOUSLY UNANALYZED CONDITION EXISTS.

APR 1987 PIR ISSUED TO DOCUMENT DETERMINATION OF SIGNIFICANCE OF UNANALYZED CONDITION.

MAY 1987 RN 8N8WP SWAPOVER LOGIC DESIGN STUDY, PART 2 CONCLUDE 8 Tl88 SPECFIC EQUIPMENT FAlLURE PREVIOUSLY UNANALYZED. DOE 8 NOT CONCLUDE RN FLOW REQUIREMENT 8 WOULD NOT HAVE BEEN MET. ADDITIONAL ANALYSIS REQUIRED.

AUG 1987 NRC REQUE8T8 ADDITIONAL INFORMATION ON RN QUESTION.DPC PROVIDE 8 RESPON8E.

LER SUBMITTED ON ERROR IN RN VALVE 1.BE-UP 30 AUG - 8 SEPT 1986. l SEP 1987 NRC CONFIRM 8 PREVIOU8 POSITION.RN '

MEET 8 GDC 5 AND 44 A8 OPERATED UNDER PROCEDURE 8.

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O O mum CONCLUSIONS THE RN SYSTEM MAS ALWAY 8 BEEN OPERATED IN A MANNER WHICH 8ATISFIES THE F8AR ACCIDENT ANALYSIS AND THE 10 CFR 50 APPENDIX A GENERAL DESIGN CRITERIA.

THE TECHNICAL 8PECIFICATION INTERPRETATitN IMPLEMENTED QN MAY 1986 PROVIDED ONLY THE EQUDPMENT/All0NMENT DETAIL 8 NECESSARY TO MEET

. THE EXISTING RN T/8 REQUIRING 2 OPERABLE RN LOOPS.lT DOD NOT MODIFY THE EXISTING T/8 AND 17 DID NOT ADD ADDITIONAL REQUIREMENTS.

THE FSAR RN DESCRIPTION ONLY ADDRESSED RN REQUIREMENTS FOR 2 UNIT 8 IN MODE 1-4 OPERATION AND HA8 BREN CLARIFIED TO REFLECT THE RN ALIGNMENT FOR OTHER UNIT / EQUIPMENT COMBINATIONS.

(SUBMITTED WITH T/8 CHANGE REQUEST).

THE NRC WA8 COGNIZANT OF THE SHARED NATURE OF THE RN SY8 TEM AND DPC EFFORT 8 TO RESOLVE QUESTIONS OF REQUIRED EQUIPMENT AND SYSTEM ALIGNMENT.

DPC IDENTIFIED ALL OF THE IS8UES DEALING WITH RN OPERAT10N WITHOUT NRC PROMPTING AND RESOLVED THEM IN A TIMELY MANNER.(INCLUDING THE VIOLATION CITED FOR THIS ENFORCHENT '

CONFERENCE).

O O MAR 14 $88 OCT 1986 DESIGN ANALYZES RN FLOW REQUIREMENTS TO SUPPORT PLANT OPERATION WITH DIESEL OUT OF SERVICE GREATER THAN 72 HOURS.

. OPERABILITY - FLOW PARAMETERS FOR ONE UNIT OPERATING AND ONE UNIT SHUTDOWN (TWO LOOPS RHR) DETERMINED. ALIGNMENT ENSURES OPERABILITY UNDER TECHNICAL SPECIFICATION AND FSAR ACCIDENT ANALYSIS EDE IER OPERABLE ELDH LOOPS.

. REPORTABILITY - FSAR DOES NOT ADDRESS AB0VE FLOW CONFIGURATION OR PLANT OPERATION WITH ONE UNIT OPERATING AND ONE UNIT IN MODES 5/6. TVIS IS CONSISTENT WITH OTHER FSAR SYSTEM DESCRIPTIONS WHICH DO NOT' ADDRESS ALL POSSIBLE UNIT / EQUIPMENT COMBINATIONS OR MAINTENANCE CONDITIONS. TECHNICAL SPECIFICATIONS ARE STILL MET AND ACCIDENT ANALYSIS IS SATISFIED.

JAN 1987 STATION PROBLEM REPORT IDEN'TIFIES POTENTIAL FOR PIT VALVE FAILURE ON SWAPOVER AND RECOMMENDS MODIFICATION.

. OPERABILITY - CONDITION DESCRIBED (DIESEL INOPERABLE >72 HOURS) NOT PRESENT.

TECHNICAL SPECIFICATIONS WOULD CAUSE BOTH UNITS TO BE SHUTDOWN IF CONDITION OCCURRED WITH BOTH UNITS IN MODES 1-4.

. REPORTABILITY - SINCE FSAR DOES NOT ADDRESS THIS PLANT CONDITION (ONE UNIT UP, ONE UNIT DOWN) IT IS NOT APPARENT WITHOUT ADDITIONAL REVIEW IF THIS FAILURE IS B0UNDED BY PRESENT FSAR ACCIDENT ANALYSIS.

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. MAR 141988 MAR 1987 RN STANDBY NUCLEAR SERVICE WATER POND SWAPOVER LOGIC DESIGN STUDY, PART 1 ISSUED.

. REPORTABILITY - STUDY CONCLUDES PROPOSED MODIFICATION MAY INVOLVE UNREVIEWED SAFETY QUESTION BY DELETING ONE OF TWO REDUNDANT SWAPOVER SIGNALS. POTENTIAL PIT VALVE FAILURE IS ALSO ADDRESSED AS "AN UNREVIEWED SAFETY QUESTION THAT NEEDS TO BE ADDRESSED." THIS STATEMENT WAS NOT INTENDED TO CONSTITUTE "AN UNREVIEWED SAFETY QUESTION" AS DEFINED IN 10 CFR 50.59, BUT AS A PREVIOUSLY UNANALYZED CONDITION WHICH REQUIRES ADDITIONAL ANALYSIS. THE ADDITIONAL ANALYSIS WOULD DETERMINE IF THIS FAILURE MECHANISM WAS REPORTABLE AS "AN UNANALYZED CONDITION WHICH SIGNIFICANTLY COMPROMISES PLANT SAFETY" AS DEFINED IN 10 CFR 50.72 AND 50.73.

APR 1987 PROBLEM INVESTIGATION REPORT (PIR) ISSUED (BASED ON FINDINGS IN THE AB0VE DESIGN STUDY)

TO DETERMINE IF THE PROBLEM DEFINED IN THE SPR IS "AN UNANALYZED CONDITION" THAT "SIGNIFICANTLY COMPROMISES PLANT SAFETY."

. OPERABILITY - POTENTIAL FAILURE MECHANISM DOES NOT CONSTITUTE NEAR TERM OPERABILITY PROBLEM. FOR DIESEL OUT OF SERVICE GREATER THAN 72 HOURS SYSTEM IS PARTIALLY ALIGNED TO POND REMOVING VALVE FAILURE AS PROBLEM.

LONGER TERM OPERABILITY QUESTION'WILL BE RESOLVED WHEN ADDITIONAL ANALYSIS IS COMPLETE.

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. REPORTABILITY - PRELIMINARY CORRESPONDENCE FOR PART 2 0F THE SNSWP SWAPOVER LOGIC DESIGN STUDY DEMONSTRATES LOW LIKELIHOOD OF EVENT IN QUESTION (I.E. SINGLE FAILURE, LOSS OF LAKE, BLACK 0UT, DIESEL IN0P). PRA ARGUMENT SEEN AS SUFFICIENT TO SHOW THIS IS NOT "AN UNANALYZED CONDITION THAT SIGNIFICANTLY COMPROMISES PLANT SAFETY" AT THIS TIME.

MAY 1987 RN STANDBY NUCLEAR SERVICE WATER POND SWAPOVER LOGIC DESIGN STUDY, PART 2 ISSUED.

. OPERABILITY - NO ADDITIONAL INFORMATION CHALLENGES THE EXISTING DETERMINATION OF CURRENT OPERABILITY.

. REPORTABILITY - THE STUDY CONCLUDES THAT THE PROBLEM IDENTIFIED IS A "PREVIOUSLY UNANALYZED SITUATION THAT NEEDS TO BE ADDRESSED." THE SINGLE ACTIVE FAILURE CAUSING LOSS OF TWO FN PdMPS IS RECOGNIZED AS WELL AS THE PROPOSED MODIFICATION, ALTERNATIVES, AND THE STATISTICAL PROBABILITY OF THE SEQUENCE OF EVENTS AFTER MODIFICATIONS. THE REPORT D0fS HDI CONCLUDE THAT THE PLANT WAS OPERATED OUTSIDE ITS DESIGN BASIS, OR THAT TECHNICAL SPECIFICATIONS WERE VIOLATED, OR THAT LOSS OF THE TWO PUMPS WOULD RESULT IN INSUFFICIENT RN FLOW FOR THE SCENERIO DESCRIBED. FOR REPORTABILITY UNDER 10 CFR 50.72 AND 50.73 THE "UNANALYZED CONDITION THAT SIGNIFICANTLY COMPROMISED PLANT SAFETY" IS CONSIDERED TO COVER THE

REQUIREMENT FOR OPERABLE FLOW LOOPS RQI

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.'- 7 O O WAR 141988 INDIVIDUAL EQUIPMENTS, NOTE THAT THE RULE ADDRESSES FAST TENSE CONDITIONS THAT EXISTED. THE PROCEDURES BY WHICH THE RN SYSTEM HAS BEEN OPERATED SINCE UNIT TWO CRITICALITY WERE DESIGNED TO ENSURE SUFFICIENT RN FLOW UNDER ALL ACCIDENT CONDITIONS. ABSENT A DISCOVERY OF THE POSSIBILITY OF PAST INSUFFICENT RN FLOW AS A RESULT OF THIS SCENERIO, IT WAS NOT DEEMED TO BE A REPORTABLE EVENT.

THE SRI ELEVATES THE ISSUE TO URI STATUS IN REPORT NUMBER 413/87-10. DPC ACTIONS TO JUSTIFY CONTINUED OPERATION AND THE ONGOING PRA/ DESIGN STUDY ARE SUMMARIZED.

JUL 1987 NRC QUALITY VERIFICATION INSPECTION (413/87-23) TEAM RAISES CONCERN THAT RN SYSTEM DESIGN IS NOT ANALYZED FOR THIS EVENT, THAT PRA IS NOT ACCEPTABLE TO DETERMINE SIGNIFICANCE, AND THAT DPC' FAILED TO REPORT UNDER REQUIREMENTS OF 10 CFR 50,72 OR 10 CFR 50,73 (THE NRC REPORT IS ISSUED IN NOVEMBER 1987),

AUG 1987 REVIEW 0F PAST INSTANCES OF PLANT IN THE CONDITION UNDER QUESTION CONCLUDE NO UNANALYZED CONDITION HAS EVER EXISTED. AN ACTUAL HEAT LOAD ANALYSIS WILL BE CONDUCTED TO RE-VERIFY THIS FOR 22 AUG - 1 SEPT 1986 TIME FRAME, NRC ISSUES REQUEST FOR ADDITIONAL INFORMATION ON RN,

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O n v MAR 14 $88 DPC PROVIDES RESPONSE TO 50.54(F) LETTER, CONCLUDES THE PLANT MEETS GDC 5 AND 44.

PROVIDES ADDITIONAL ANALYSIS THAT A SINGLE RN PUMP CAN REMOVE HEAT LOADS EXPECTED DURING POSTULATED CONDITIONS UNDER QUESTION (INCLUDING LOCA), AND PROVIDES JUSTIFICATION FOR CONTINUED OPERATION.

A REVIEW 0F VALVE LINE-UP DATA USED TO CONFIGURE RN FOR THE 30 AUG - 8 SEPT 1986 TIME FRAME IDENTIFIES ERROR. THIS ERROR IS DETERMINED REPORTABLE UNDER 10 CFR 50.73 AND LER 413/87-36 IS SUBMITTED.

SEP 1987 NRC ISSUES LETTER CONFIRMING RN SYSTEM MEETS GDC 5 AND 44 AS OPERATED UNDER PROCEDURES IN PLACE. REQUESTS TECHNICAL SPECIFICATIONS BE MODIFIED TO REFLECT SHARED ASPECTS OF RN SYSTEM.

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MAR 14 $88 CATAWBA NUCLEAR STATION TECHNICAL SPECIFICATION INTERPRETATION TECHNICAL SPECIFICATION (S) AFFECTED: 3.7.4, Nuclear Service Water System REVISION: 0 DETAILS:

The Nuclear Service Water System (RN) contains pumps which are unit designated, i.e., lA, 2A, 1B, 2B, yet supply both units through common discharge piping. All RN pumps receive auto-start signals from a safety signal on either unit. Accordingly, the following interpretations are made with respect to RN System OPERABILITY:

An RN pump designated to one unit may be assumed to supply post i accident RN requirements to equipment on the opposite unit 1

provided its associated emergency diesel generator is OPERABLE '

AND RN system valve alignments are such that the required RN equipment will receive the required flows. ,

Since three RN pumps can supply sufficient flow for four RN trains but cannot do so if a single failure occurs, this  !

configuration does not represent two independent RN trains for l each unit. Therefore, with only three RN pumps OPERABLE, the l action stetament for one RN train out of service must be entered 1 for both units or sufficient RN supplied equipment isolated.

This assures that the required post-accident flows will be

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I supplied to the remaining OPERABLE RN suppli'ed equipment in the l event of any single failure. Only isolated RN supplied equipment must be declared inoperable.

If less than three RN pumps are OPERABLE, both units must enter .

Tech Spec action statement 3.0.3 until sufficient RN supplied I equipment is isolated to assure that at least one RN train ~per unit or two trains on the same unit, will receive the required post-accident RN flows.

BASIS: Review of Technical Specification. Discussion with Design Engineering.

APPROVAL: = Ms J. W. Hampton,~ Manager Catawba Nuclear Station DATED: 5 - /r- rc