ML20198G650
| ML20198G650 | |
| Person / Time | |
|---|---|
| Site: | 05000000, Palo Verde |
| Issue date: | 12/05/1985 |
| From: | Dircks W NRC OFFICE OF THE EXECUTIVE DIRECTOR FOR OPERATIONS (EDO) |
| To: | |
| Shared Package | |
| ML082340299 | List: |
| References | |
| FOIA-86-45, REF-GTECI-A-45, REF-GTECI-DC, TASK-A-45, TASK-OR SECY-85-384, NUDOCS 8512160324 | |
| Download: ML20198G650 (34) | |
Text
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POLICY ISSUE (Information)
December 5,19E3 SECY-85-384 FOR:
The Commissioners FROM:
William J. Dircks Executive Director for Operations
SUBJECT:
DESIGN ADEQUACY OF THE AUXILIARY PRESSURIZER SPRAY SYSTEM AT PALO VERDE NUCLEAR GENERATING STATION PURPOSE:
To inform the Commission of the staff actions concerning the adequacy of the auxiliary pressurizer spray system as installed at Palo Verde Unit 1 in light of the September 12, 1985 event.
BACKGROUNO:
This report has been prepared in response to Commissioner Zech's request regarding the subject matter relative to the September 12, 1985 event at Palo Verde Unit 1.
Palo Verde Nuclear Generating Station was designed without power operated relief valves (PORVs) on the pressurizer.
The plant design relies on the auxiliary pressurizer spray system (APSS) as a means of rapidly depressurizing the primary coolant system for plant shutdown and accident mitigation.
Since the APSS performs safety-related functions, it has been stated by the licensee that it has been designed to safety grade standards.
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 pressurizer spray system in lieu of PORVs prior to the resolution of USI-A45 was based on its understanding that the auxiliary pressurizer spray system was designed to safety grade standards.
Contact:
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The Commissioners
- 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.,
boron addition) and (2) GDC 33 requires that a system be provided to supply reactor coolant makeup for l
protection against small breaks in the reactor coolant pressure boundary (i.e., when the reactor coolant system is at operating pressure).
DISCUSSION:
I.
Palo Verde Event On September 12, 1985, Arizona Nuclear Power Project (ANPP) conducted a loss-of-load test on the Palo i
Verde Nuclear Generating Station Unit 1 from ap-proximately 55% power.
The plant did not perform 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.
The reactor and turbine trip's were not expected.
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 j
by the automatic initiation of containment isolation.
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 suction of the 1
charging pumps from the VCT to other water sources, if power supplies had been available to j
realign the valves involved.
Also, after the containment isolation signal was received, all makeup flow to the VCT was isolated.
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i The Commissioners.
1 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 locally vented by an operator in an attempt to remove the hydrogen gas.
After non-class 1E power was restored, water supply from the RWT via boric acid makeup pumps was delivered to charging pumps, and charging flow to RCP seal injection, and reactor coolant systems were established.
Subsequently, the RCS pressure and inventory reached stable conditions and the unusual event was terminated.
II.
Staff Actions on Palo Verde Event 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 commitment 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. The ANPP letter of September 18, 1985 l
discussed the September 12, 1985 event and briefly addressed concerns relating to the auxiliary spray system.
At a meeting on September 20, 1985, ANPP provided a more in-depth discussion of the events and further discussed the auxiliary spray system.
At the conclusion of the September 20, 1985 meeting, ANPP committed to certain short-term compensatory measures which justified continued operation of the facility while the long-term 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 4
i issue for the auxiliary spray system.
On the basis i
of the ANPP commitments to implement the agreed-upon i
compensatory measures, the Region V Office of the NRC l
issued a followup Confirmatory Action Letter, dated September 20, 1985, describing the commitments and stating that adequate short-term compensatory j
measures are in place for restart of Palo Verde Unit i
1.
The letter also stated that long-term measures to assure the reliability of the auxiliary spray system i
would be the subject of future correspondence.
1 l
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The Commissioners On October 2, 1985, a letter was issued to the licensee pursuant to 10 CFR 50.54(f) to require that the licensee furnish in writing, under oath or affirmation, within 20 days of the date of this letter, its plans, program and schedule to bring l
Palo Verde Unit 1 into conformance with its licensing basis.
A request for additional information was enclosed in this letter as follows:
1.
The Palo Verde design includes a safety grade auxiliary pressurizer spray system.
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 APSS intends to make to upgrade the auxiliary spray system to safety grade standards and provide the schedule by which this effort will be accomplished.
2.
The auxiliary spray system was stated to be safety grade on the Palo Verde docket and then later determined to have single failure vul-nerabilities and other deficiencies.
Provide a detailed explanation of how the QA process, I
which should include an independent review and verification of design adequacy, did not detect these deficiencies in the auxiliary spray system.
Also provide a description of the corrective actions APSS intends to take to remedy any weaknesses identified.in the QA process.
j 3.
Provide a detailed description of what APSS considers to be safety grade design requirements and how these requirements are applied to systems and components that are specified as safety related.
In particular, discuss how these requirements were applied to the auxiliary spray system and whether the identified de-ficiencies in auxiliary spray system were due to a failure to apply them to the system.
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The Commissioners
- The Arizona Nuclear Power Project (ANPP) has responded to the above staff concerns in letters dated October 15, 1985, October 22, 1985, and November 4, 1985.
The licensee's submittals include a reanalysis of a postulated steam generator tube rupture event in which the auxiliary pressurizer spray system is assumed inoperable and the pressuri-zer gas vent valves are used for RCS depressurization during the transient.
The staff's preliminary evaluation of this submittal concludes that the results of the reanalysis are acceptable. The ANPP also committed a list of enhancement to be applied to the auxiliary pressurizer spray system (APSS) water supplies.
The staff finds these proposed enhancements could improve the reliability of the APSS function.
However, the staff is preparing a request for addi-tional information (RAI) for certain clarification of the ANPP submittal.
The staff is planning to com-plete the review of this issue prior to the issuance of Palo Verde Unit 2 license.
i The s'taff addressed this issue in the ACRS Sub-committee meeting November 5, 1985, and ACRS full committee meeting November 7, 1985, on CESSAR/Palo Verde Nuclear Generating Station. The ACRS has not yet written a letter on this matter.
sts
- Willi
. Dircks Executive Director for Operations DISTRIBUTION:
Conunissioners OGC OPE OI OCA EDO ACRS SECY i - -.
II.B.
th1T i POWER ASCENSION TESTING EXPERIENCE
- 1. GENERAL OPERATING PERFORMANCE
- 2. EXPERIENCE WITH POWER RUNBACK SYSTEM LOAD REJECTION TEST EXPERIENCE - ROOT CAUSE OF PROBLEMS EXPERIENCED e
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.e DEVELORENT OF PAT PRO @M SCHDULE
. ACTUAL TEST PR08M DLRATION AT OTER & PLANTS SCOPE OF TESTING FOR PVNGS vs. Ol}ER PLANTS ACTUAL TEST TRE TEST PREDICTIONS vs. TEST RESULTS VERY GOOD A8EEMENT BETWEEN PREDICTION /RESULTS f
to LEXPLAINED TEST RESULTS OR PLANT TRANSIENT RESPONSE PLANT TRIPS: 7 1 RIPS (TWO WHILE TESTING)
TWO MAIN FEED PlW TRIPS OE &AC CIROJIT BOARD FAILlRE TFREE LOSS OF FWER TRIPS (ONE WILE TESTING)
OE S/G L(W LEVELS TRIP (WILE TESTING)
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REACTOR POWER CUTBACK SYSTEM
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A CONTROL. GRADE SYSTEM TO EliHANCE THE UNITS AVAILABILITY.
I THE SYSTEM IS DESIGflED TO OPERATE IN C0flJUf4CTION WITH THE STEAM BYPASS CONTROL SYSTEM TO DROP SELECTED CEA'S FOR:
A LOSS OF FEED PUMP
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A LOAD REJECTION TO MATCH STEAll BYPASS CAPABILITY WITH REACTOR POWER.
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T EXPERIENCE WITH REACTOR POWER CUTBACK SYSTEF TEST PERFORMED LOSS OF FEED PUFP BELOW 50% - SUCCESSFUL J
NO REACTOR POWER CUTBACK SECOND PUMP ASSUMED LOAD LOSS OF FEED PUMP AT 70% - SUCCESSFUL TURBINE SETBACK NO REACTOR POWER CUTBACK LOSS OF LOAD FROM 50% - INITIAL TEST : UNSUCCESSFUL
- SECOND TEST
- SUCCESSFUL NO REACTOR POWER CUTBACK LOSS OF LOAD FROM 80% - INITIAL TEST : UNSUCCESSFUL REACTOR POWER CUTBACK ACTUATION TURBINE SETBACK TESTS TO BE PERFORMED I
RE-PERFORM LOSS OF LOAD FROM 80%
LOSS OF FEED PUMP FROM 100%
LOSS OF LOAD FROM 100%
GWW 11/05/85
SUMMARY
OF OCTOBER 24, 1985 EVENT PLANT WAS PREPARING FOR THE LOSS OF LOAD TEST FROM 80% POWER PLANT INITIAL CONDITIONS 83% REACTOR POWER TURBINE / GENERATOR CONNECTED TO GRID ALL STATION LOADS BEING FED FROM 0FFSITE POWER SOURCES ANTICIPATED RESULTS OF TEST NO REACTOR TRIP RPCS ACTUATES TO REDUCE POWER ACTUAL TEST RESULTS REACTOR TRIP CONCURRENT WITH TURBINE TRIP REACTOR POWER CUTBACK DID NOT OCCUR DUE TO REACTOR TRIP ALL SAFETY SYSTEMS PERFORM PER DESIGN GWW 11/05/85 6
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REACTOR TRIP #7 (RPG) 10-24-85 M
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-STEAM BYPASS QJIO( OPEN 1010.30-1-SIAS/CIAS/MSIS I
1011.00-1-2 RCP's TRIPPED 1
1012.00 - --fPSI IKIECTION FL(M STOPPED 1013.00 - --ATMDSPERIC VALVES OPENED 1015.00- -NON-SEISMIC AFWS P&P STARTED I
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1046.00 - --RESET SIAS/CIAS I
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ROOT CAUSE EVALUATION OCTOBER 24, 1985 EVENT REACTOR TRIP CAUSE - SG LOW LEVEL SIGNAL T00 FAST TO ACCOMMODATE PRESSURE WAVE CORRECTIVE MEASURE - INCREASE REACTOR TRIP BISTABLE RESPONSE TIME FOR SG LOW LEVEL C00LDOWN OF PRIMARY SYSTEM
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CAUSE - INCORRECT SETPOINT IN STEAM BYPASS CONTROL SYSTEM CORRECTIVE MEASURE - ADJUSTED SETPOINT IN THE STEAM BYPASS C-0NTROL
- REVERIFICATION OF ALL SETP0INTS IN SBCS, FWCS, RRS GWW 11/05/85
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J H.C.
_ AUXILIARY PRESSURIZER SPRAY SYSTEM (APSS)
- i. APSS DESIGN
- 2. APSS OPERATIONS SEPTEMBER 12,1985 EVENT Root CAUSE EVALUATION
- 3. APSS DESIGN ENHANCEMENT i
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- 4. SGlR ANALYSES f
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AllXT1 TARY FRESSLRI7ER SFRAY PLRPOSE:
PROVIDE A WANS FOR REACTOR 000UWT SYSTEM DEFRESSLRHATION, WEN PAIN PRESSLRIZER SPRAYS ARE NOT AW.ILABLE ESTMllSID DESI61 CRITERIA:
BPA Oi TECH 1ICAL POSlTION RSB 5-1. FOR A 0 ASS 2 PLANT
- OPERATOR ACTI0tS OUTSIDE CONTROL R001
- OPERATOR ACTIONS INSIDE m1TAIMiENT AFTER SSE PIPAINING AT FOT ST#0BY LNTIL MAMJAL ACTIONS OR REPAIRS ARE COPLETED l
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i SPPLIFIED SCID MTIC 0F PALO VERDE CVCS Sluf1NG NJXILIN1Y SPIMY TmTION i
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Q.ASSIFICATIONOF1 EWi SEJ ENVE DF U TAL
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0@F0ENTS CODE CATEG0RY IE PWER WALIFICATIM l
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CH-239 III CLASS 2 I
NON-IE YES CH-240 III. CLASS 1 I
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I 101-203 IIII CLASS i I
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a SIWLIFIED SCIEMATIC 0F PALO VERDE CVCS SINING SOLAtCES OF DmAlED WATER FOR AUXILIN(Y SPRAY fearlInstlC KID panessian sum I.I DU j','; *'L ggh,"
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0.ASSIFICATION OF MAJOR OTP0E NTS ASME l
SET 5fif 1 ENVIRO & ENTAL O&fMNTS CODE CATEGORY
.IE PWER OUALIFICATION I
CHARGING PUNPS (3)lIII, CLASS 2, i
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.CH-536 III, CLASS 3.
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SLM%RY OF SEPTEtER 12,1985 EVENT PREPARING TO PERFORM A LOAD REJECTION TEST If4ITIAL PLAffT C0f0ITIONS REACTOR AT 53% P0tER TUP 3IfE/GEfERATOR C0fifECTED TO GRID N0li-CLASS STATION LOADS ON GEfERATOR TEST STARTED BY IrlITIATIf4G LARGE LOAD REJECTI0fl EXPECTED RESLLTS OF TEST NO REACTOR P0tER CUTBACK SYSTEM ACTUATION NO REK TOR TRIP ACTUAL RESLLTS OF TEST NO REACTOR P0'ER CUTBACK SYSTEM ACTUATION REACTOR TRIP OCCURRED GW 11/05/85
REACTOR TRIP #4 09-12-85 TIf1E 2208.29 OPEN GENERATOR BREAKER 918 REACTOR TRIP (RCP SPEED 90%)
2208.53 2210.00 OPERATOR CLOSES MAIN STEAM LINE DRAINS LOST STATION LOADS 2210.53 2213.00 NATURAL CIRCULATION ESTABLISHED 2215.00 STARTS NON-SEISMIC AFWS PUMP 2218.00 RESTORED STATION LOADS MAIN STEAM LINE DRAIN VALUES REOPEN 2222.00 SIAS/CIAS 2224.00 HPSI FLOW INJECTION STOPS 2230.00 OPERATOR SECURES ALL 3 CHARGING PUMPS 2232.00 LINED UP GRAVITY FEED 0000.00 STARTED BAM PUMPS 0002.00 STARTED CHARGING PUMPS B AND C 0102.00 RESULT SIAS & CIAS RESTART 2 RCP'S GWW 11/05/85 l
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ROOT CAUSE EVALUATION SEPTEMBER 12,1985 C00LDOWil 0F PRIMARY SYSTEM CAUSE RE0PENIf1G 0F IIAIN STEAM LINE DRAIN VALVES CORRECTIVE MEASURES REMOVE AUTO OPEllING 0F VALVES ON TURBINE TRIP LOSS OF POWER TO N0ft-ESSEf1TIAL STATION LOADS CAUSE INABILITY OF THE TURBINE / GENERATOR TO MAINTAlfi HOUSE LOADS CORRECTIVE MEASURES i10DIFY THE TURBIllE SUPERVISORY SYSTEM fl0DIFY TURBINE ELECTRO-HYDRAULIC CONTROL SYSTEf1 LOSS OF CHARGING FLOW CAUSE INACCURATE VCT LEVEL INDICATION CORRECTIVE MEASURES DAILY SURVEILANCE OF REFERENCE LEG REVISE PROCEDURES TO LIllEUP CHARGIf1G PUMP SUCTI0ft fl0DIFY PROCEDURES TO WARf1 OPERATORS OF POTENTIAL LOSS OF SUCTION TO THE CHARGING PUMPS VARIOUS ADMINISTRATIVE ENHANCEMENTS DESIGN EllHANCEf1ENTS GWW 11/05/85
MODIFICATION
SUMMARY
ADD SECOND, DIVERSE REFERENCE LEG TO VCT LEVEL TRANSMITTERS ADDRESSES ROOT CAUSE OF LOSS OF CHARGING EVENT REPLACES HEED FOR DAILY REFERENCE LEG CHECK J
PROVIDE POWER TO VCT OUTLET AND RWT GRAVITY FEED LINE VALVE FROM 1E MCC ELIMINATES HEED TO MANUALLY RESTORE POWER TO THE VALVES FROM OUTSIDE THE CONTROL ROOM FOLLOWING AN SI AS ADD AUTOMATIC ACTUATION TO GRAVITY FEED LINE VALVE ELIMINATES THE NEED TO MANUALLY OPERATE THE GRAVITY FEED LINE VALVE FROM THE CONTROL ROOM DURING LOSS OF 0FFSITE POWER CONDITIONS LOCK OPEN TWO NORMALLY OPEN VALVES IN AUXILIARY SPRAY FLOW PATH ELIMINATES P0TENTIAL FOR ISOLATION OF GRAVITY FEED OR CHARGING LINE DUE TO SPURIOUS ACTUATION OR OPERATOR ERROR MAR 11/05/85 9
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STEAM GENERATOR TWE RUPTlRE ANALYSIS EXPLAIN THE USE OF AUXILIARY PRESSURIZER SPRAY IN THE PALO VERDE STEAM GENERATOR TUBE RUPTURE ANALYSIS DEMONSTRATE THAT THE DOSE CONSEQUENCES FOR THE PALO VERDE SGTR ANALYSIS ARE RELATIVELY INSENSITIVE TO THE TIME AUXILIARY PRESSURIZER SPRAY IS INITIATED SHOW THAT AN ALTERNATIVE SYSTEM EXISTS TO FACILITATE DEPRESSURIZATION FOLLOWING A STEAM GENERATOR TUBE RUPTURE GJS 11/05/85
1 i
ANALYSIS
SUMMARY
(1)
PVNGS FSAR APPENDIX 15A STEAM GENERATOR TUBE RUPTURE LOSS OF 0FFSITE POWER RECCGNIZED EMERGENCY OPERATING GUIDELINES FULLY STUCK OPEN ATMOSPHERIC DUMP VALVE AUXILIARY PRESSURIZER SPRAY OPERATION AT 1015 C2)
OCTOBER 15, 1985 SUBMITTAL SAME AS (1) EXCEPT:
AUXILIARY PRESSURIZER SPRAY OPERATION AT TWO 3)
NOVEMBER 4, 1985 SUBMITTAL SAME AS (2) EXCEPT:
NC AUXILIARY PRESSURIZER SPRAY PRESSURIZER VENT OPERATION AT TWO HOURS GWS 11/05/85
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COM,?ARIS0N OF THE RCS PRESSURE RESPONSE FOLLOWING A SGTR WITH AUX SPRAY INITIATED AT 1015 SECONDS vs 2 HOURS 2500
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i OPERATOR TAKES CONTROL OF PLANT-0 PENS ONE ADV IN EACH SG 2000 PERATOR INITIATES AUXILIARY SPRAY m
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OPERATOR BEGINS TO THROTTLE HPSI FLOW
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t RCS REACHES SHUTDOWN 500
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COOLING ENTRY CONDITIONS
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0 5,000 10000 15000 2000 25000 30000 TIME, SECONDS SGTR WITH AUX SPPAY AT 1015 SECONDS
---SGTR WITH AUX SPRAY DELAYED UNTIL 2 H00RS STEAM GINERAMR TURE MIPWRE WITH ICSS i
OF CFT5ITE POWER AND A FULLY SWCK M
PRE-ACCIDENT I0 DINE SPIKE THYR 0ID DOSE-REM 2 HOUR DOSES 8 HOUR DOSE EXCLUS10fi AREA LOW POPULA110N BOUtiDARY ZONE (REM)
(REM)
PVNGS FSAR 200 41 APPEllDIX 15A AUX-SPRAY AT 1015 SEC0f1DS AUX-SPRAY AT 208 44 TWO HOURS 10CFR100 DOSE LIMIT IS 300 REM GWS 11/05/85 au
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DEPRESSLRIZATIDN DLRING A SGIR DEPRESSURIZATION RESULTS PRIMARILY BY THROTTLING ffSI FLOW i
BEFORE IFSI FLOW IS THROTTLED. LEVEL IN THE PRESSURIZER MUST BE RECOVERED i
AUXILIARY PRESSURIZER SPRAY IS USED TO RESTORE LEVEL I.
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RESSLRIZER VENT PATHS C,odTAIdME.dT ATM os ME3E n
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l CLASSIFICATION OF MAJOR (IMFGDITS I
I ASME
.l SEISiIC I EINIRCtNENTAL )
I COMFTTS 0]DE CATEGJRY l IE F0WER CUALIFICATION l l
RC-103 IIII. CLASS 2.
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A I
YES l
1 RC-105 l'III. CLASS 2L I
l B
YES I
l RC-106 IIII. CLASS 2 I
I A
YES I
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l RC-108 III. CLASS i' I
l B
YES I
RC-109
)III. CLASS i I
B YES (MS
COMPARIS0N OF THE RCS PRESSURE RESPONSE FOLLOWING A SGTR WITH AUX SPRAY INITIATED AT 2 HOURS vs PRESSURE vet!T OPENING AT 2 HOURS 2500 i
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OPERATOR TAKES CONTROL OF PLANT-0 PENS ONE EACH SG i
2000
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OPERATOR INITIATES DEPRESSURIZATION 5
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RCS REACHES
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s SHUTDOWN COOLING 500 ENTRY CONDITIONS M,
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O 5,000 10000 13000 20000 25000 30C00 TIME, SECONDS SGTR WITH AUX SPRAY AT 2 HOURS
---SGTR WITH PRESSURIZER VENT 'AT 2 HOURS t
sma aanzusen wu muPmm wm wss OF QFFSITE POWER AND A FULLY STUCK OPDt ATHOSPM RIC DUMP VALVE
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PRE-ACCIDENT IODINE SPIKE THYROID DOSE-REM 2 HOUR JOSES 8 HOUR DOSE EXCLUS10'4 AiEA LOW POPULATION B0UNDARY ZONE (REM)
(REM)
PVf;GS FSAR 200 41 APPEi; DIX 15A AUX-SPRAY AT 1015 SEC0f;DS AUX-SPRAY AT 208 44 TWO HOURS PRESS'JRIZER 208 44 VEf;T AT TWO HOURS l
10CFR100 DOSE LIMIT IS 300 REM GWS 11/05/85 1
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Set %RY DOSE RESULTS ARE RELATIVELY INSENSITIVE TO THE TIME OF AUXILIARY PRESSURIZER SPRAY ACTUATION DURING THE FIRST TWO HOURS 10CFR100 DOSE LIMITS ARE NOT EXCEEDED WHEN APSS USE IS DELAYED UNTIL TWO HOURS AFTER THE EVENT INITIATION AN ALTERNATE SYSTEM EXISTS THAT CAN BE USED TO FACILITATE DEPRESSURIZATION DURING A STEAM GENERATOR TUBE RUPTURE. WITH NO IMPACT ON THE DOSE CONSEQUENCES.
I sa 11/05/85
AUXILIARY PRESSURIZER SPRAY
SUMMARY
3 THE AUXILIARY PRESSLR:ZEF. SPRAY SYSTEM DESIGfl MEETS THE REQUIREMENTS OF BTP RSB 5-1.
3 THE OPERATORS SUCCESS:ULLY DEALT WITH THE LOSS OF CHARGING IN THE SEPTEMBER 12 EVENT.
3 C0f: pef 1SATORY I;EASURES HA\\E BEEN TAKEfi TO REDUCE THE PROBABILITY OF A TEMPORARY LOSS OF Ch A:GII.3.
DESIGN ENHANCEMEflTS ARE BElfiG MADE TO REPLACE SOME OF THE C:f?ENSATORY MEASURES.
3 ADDITI0f1AL STEA'; gel;E: ATCR TUBE RUPTURE AflALYSES CLARIFY THE REQUIREf1ENT FOR USE OF THE AUXILI ARY FRESSURIZER SPRAY, OR THE BACKUP VENT, TO MINIMIZE OFFSITE DOSE.
GWS 11/05/85 O
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SUMMARY
OF 308TH ACRS MEETING - December 5-7, 1985 R. W. HERNAN I.
Agenda Items of Interest to NRR
- Proposed Rule Change to 10 CFR55 - Operator Licensing
- Requalification of Reactor Operators - Asselstine Questions
- GESSAR II Severe Accident Review and FDA
- Millstone,1 FTOL Review
- Prioritization of New Generic Issues
- Status Review of USI A-45 Resolution
- Status of Implementing Quantitative Safety Goals
- Auxiliary Feedwater System Reliability
~
- Palo Verde 1 Startup Experience
- Source Term Reassessment - Review of NUREG-0956 II.
Letters to be Issued
- Millstone 1 FTOL - letter supports issuance of FTOL.
- Prioritization of new generic issues - letter agrees with the staff's priorities with one exception.
- Rule change on operator licensing - letter endorses rule change with minor comments.
12/16/85 1
SUMMARY
OF 308TH ACRS MEETING I
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?
9
- It is not clear that all AFW systems have been fully upgraded to safety grade (and are on the Q list) or that they meet the staff's current SRP criteria.
- It is not clear what direction the proposed CRGR package /
generic letter will take in the future, particularly in light of the NRR reorganization.
- The staff was unable to articulate a schedule for resolution of reliability concerns on the AFW systems of several older plants.
- ACRS will issue a letter expressing the above concerns.
I.
Palo Verde Unit 1 Startup Experience
- The staff reviewed the Palo Verde 1 power ascension testing experience with the ACRS on November 7, 1985, as requested in the 1981 ACRS letter.
- The ACRS had drafted a letter on this review during the November full-Committee meeting but ran out of time before it could be finalized. During additional discussion on December 7, the ACRS
~
decided not to issue a letter. The staff had not requested a letter and lack of a letter will have no impact on staff licensing actions for Unit 2.
7-IV.
Future Activities
- Subcommittee meetings
- NRR to discuss allegation resolution NRR(Brady)
- 1/6 Standard Plant Policy Statement PWR-B/SSPD
- 1/7 OR Events Briefing (incl San Onofre 1 (PWR-A,PWR-B RanchoSecoandCrystalRiver)
(BWR 12/16/85 6
SUMMARY
OF 308TH ACRS MEETING
-