ML13333B994
| ML13333B994 | |
| Person / Time | |
|---|---|
| Site: | San Onofre  |
| Issue date: | 12/22/1983 |
| From: | Paulson W Office of Nuclear Reactor Regulation |
| To: | Office of Nuclear Reactor Regulation |
| References | |
| LSO5-83-12-032, LSO5-83-12-32, NUDOCS 8312230226 | |
| Download: ML13333B994 (45) | |
Text
December 22, 1983 Docket No. 50-206 LS05-83-12-032 LICENSEE: SOUTHERN CALIFORNIA EDISON COMPANY FACILITY:
San Onofre Nuclear Generating Station, Unit No. 1
SUBJECT:
SUMMARY
OF DECEMBER 9, 1983 MEETING On December 9, 1983, members of the NRC staff met with representatives of Southern California Edison Company (SCE). The purpose of the meeting was to discuss SCE's return to service plan for San Onofre Unit No. 1. is a list of attendees.
SCE discussed the current plant status, seismic hazard, and safe shutdown systems. Enclosure 2 is a copy of the handouts used during the meeting.
SCE stated that (1) based on the current state of the plant and current knowledge, the seismic hazard for San Onofre Unit No. 1 should no longer be a significant concern; and (2) all structures, systems, and components required to safely shutdown following an earthquake will be individually evaluated prior to return to service to ensure their availability follow ing a 0.67g earthquake.
Original signed by Walter A. Paulson, Project Manager Operating Reactors Branch #5 Division of Licensing
Enclosures:
As stated cc w/enclosures:
See next page DLVRB #5 D
WPaulson:cc DW tchfield 11V/V /83
(', /2
/83 8312230226 831222 PDR ADOCK 05000206 P
2 -
December 22, 1983 cc Charles R. Kocher, Assistant Mr. K. Baskin, Vice President General Counsel Nuclear Engineering James Beoletto, Esquire Licensing and Safety Department Southern California Edison Company Southern California Edison Company Post Office Box 800.
2244 Walnut Grove Avenue Rosemead, California 91770 Post Office Box 800 Rosemead, California 91770 David R. Pigott Orrick, Herrington & Sutcliffe 600 Montogmery Street San Francisco, California 94111 Harry B. Stoehr San Diego Gas & Electric Company P. 0. Box 1831 San Diego, California 92112 Resident Inspector/San Onofre NPS c/o U.S. NRC P. 0. Box 4329 San Clemente, California 92672 Mayor City of San Clemente San Clenente, California. 92672 Chairman Board of Supervisors County of San Diego San Diego, California 92101 California Department of Health ATTN:
Joseph 0. Ward, Chief Radiation Control Unit Radiolooical Health Section 714 P Street, Room 498 Sacramento, California 95814 U.S. Environmental Protection Agency Region IX Office ATTN:
Regional Radiation Representative 215 Freemont Street San Francisco, California 94111 John B. Martin, Regional Administrator Nuclear Reculatory Commission, Region V 1450 Maria Lane Walnut Creek, California 94596
ENCLOSURE 1 ATTENDANCE LIST December 9, 1983 Meetinq San Onofre Unit No. 1 NAME AFFILIATION 1W. A. Paulson NRC R. L. McNeill SCE Consultant M. N. Shulman Impell R. W. Krieger SCE K. P. Baskin SCE H. R. Denton NRC L. Bernath SDG&E M. 0. Medford SCE P. Koss Bechtel C. I. Grimes NRC D. M. Crutchfield NRC V. A. Moore NRC R. J. Mattson NRC J. P. Knight NRC R. A. Purple NRC
ENCLOSURE 2 0e RETURN TO SERVICE PLAN SAN ONOFRE UNIT 1 NRC MEETING DECEMBER 9, 1983
AGENDA I.
INTRODUCTION K. BASKIN II. CURRENT PLANT STATUS R. KRIEGER III. RETURN TO SERVICE PLAN R. KRIEGER A.
SEISMIC HAZARD
- 1. GROUND MOTION R. MCNEILL
- 2. EARTHQUAKE EXPERIENCE R. MCNEILL
- 3. SEISMIC RISK R. KRIEGER B.
- 1. SAFE SHUTDOWN SYSTEMS R. KRIEGER
- 2. ACCEPTABILITY CRITERIA M. SHULMAN IV.
SUMMARY
K. BASKIN
CURRENT PLANT STATUS MODIFICATIONS PRIOR TO 1982 0
REACTOR COOLANT LOOP EQUIPMENT SUPPORTS INSTALLED 0
CONTAINMENT OKAY AS IS 0
NEW SPHERE ENCLOSURE BUILDING 0
NEW DIESEL GENERATOR BUILDING 0
NEW DIESEL GENERATORS AND AUXILIARY SYSTEMS 0
NEW AUXILIARY FEEDWATER DISCHARGE PIPING 0
SERVICE WATER RESERVOIR OKAY AS IS 0
ELECTRICAL EQUIPMENT ANCHORAGES MODIFIED 0
CONTROL BUILDING AND SEAWALL OKAY AS IS
CURRENT PLANT STATUS MODIFICATIONS SINCE 1982 0
TURBINE BUILDING STRUCTURAL MODIFICATIONS INSTALLED (SOUTH TURBINE EXTENSION NOT COMPLETED) 0 MODIFICATIONS TO MASONRY WALL CONNECTIONS IN THE VENTILATION BUILDING, REACTOR AUXILIARY BUILDING AND FUEL BUILDING INSTALLED. ADDITIONAL MODIFICATIONS TO MASONRY WALLS INSTALLED IN THE TURBINE BUILDING 0
MASONRY WALL TEST PROGRAM SUCCESSFULLY COMPLETED 0
STRENGTHENING BRACE ADDED TO THE FUEL BUILDING AT THE EAST WALL OF THE NEW FUEL ROOM 0
STRENGTHENING BEAM ADDED TO THE INTAKE STRUCTURE PUMP WELL WALLS 0
IN-SITU SOIL CONDITIONS MAPPED AND DEFINED 0
APPROXIMATELY 1,800 OF 4700 PIPING SUPPORTS MODIFIED OR INSTALLED 0
APPROXIMATELY 400 OF 600 CABLE TRAY MODIFICATIONS INSTALLED OR MODIFIED 0
APPROXIMATELY 1300 OF 1500 MODIFICATIONS TO CONDUIT SUPPORTS INSTALLED OR MODIFIED 0
APPROXIMATELY 300 OF 600 CABLE TRAY TIEDOWN LOCATIONS MODIFIED 0
A NEW SEISMICALLY QUALIFIED CONTROL ROOM CEILING INSTALLED 0
A NEW AUXILIARY FEEDWATER TANK CONSTRUCTED 0
CONTAINMENT SPRAY RINGS MODIFIED
RETURN TO SERVICE PLAN 0
SEISMIC HAZARD BASED ON CURRENT STATE OF THE PLANT AND CURRENT KNOWLEDGE, THE SEISMIC HAZARD SHOULD NO LONGER BE A SIGNIFICANT CONCERN FOR THE PLANT AS A WHOLE.
0 SAFE.SHUTDOWN ALL STRUCTURES, SYSTEMS AND COMPONENTS REQUIRED TO SAFELY.
SHUT DOWN FOLLOWING AN EARTHQUAKE WILL BE INDIVIDUALLY EVALUATED TO ENSURE THEIR AVAILABILITY FOLLOWING A 0.67G EARTHQUAKE PRIOR TO RETURN TO SERVICE.
SEISMIC HAZARD 0
GROUND MOTION 0
EARTHQUAKE EXPERIENCE 0
SEISMIC RISK
IGNORING GROUND BREAKAGE (FAULTING, LIQUEFACTION, LAND SLIDES), AND OLD OR UNREINFORCED STRUCTURES, STRUCTURAL DAMAGE DUE TO EARTHQUAKES IS QUITE SMALL
SOME REASONS FOR DIFFERENCE BETWEEN OBSERVED STRUCTURAL BEHAVIOR AND INSTRUMENTAL STRONG GROUND MOTIONS ARE:
- 1. FOUNDING OF INSTRUMENTS
- 2. STATISTICS OF THE PROCESS
- 3.
SOIL STRUCTURE INTERACTION
- 4.
RESERVE CAPACITY
FOUNDING OF INSTRUMENTS 0
THE WAY MANY INSTRUMENTS USED TO MEASURE EARTHQUAKE DATA ARE FOUNDED TENDS TO DISTORT GROUND ACCELERATION.
- 2.
STATISTICS OF THE PROCESS 0
USUAL PRACTICE USE EXPECTED VALUE RELY ON SAFETY FACTORS AND RESERVES FOR LOWER PROBABILITIES 0
CRITICAL FACILITIES USE 84TH PERCENTILE
HORIZONTAL PEAK GROUND NITUDE Ms IAN MEDIAN +
MEDIAN + 20 6.05 0.24 0.38 0.63 6.0 0.29 0.46 0.71 6.5 0.33 0.52 7.0
- 10 10 107 10-U0-
/.
o
//
CL 7 /
cf-f 0
LIO LUL 10
~~FIGURE-1 -,-SEISMIC -HA'ZARt5 CURVES SAN ONOFRESITE CALCUL ATION BYi --
WOODWARD -. CLYDE TER'A
-~
I 10 O
0.1 0.2 03 0.4 0.5 0.6 0.7 0.8 0.9 1.0 1.1 1.2 INSTRUMENTAL PEAK GROUND ACCELERATION.
9
- 3.
SOIL STRUCTURE INTERACTION 0
DEPTH, AREA, (MASS) 0 DATA EFFECTS OF BASEMENT COMPLETE EFFECTS
E 0
- 4.
0 0
E 3 0
CC O0 0
In E.
Bcemn oao 0
0-preduing onmotion.
C)C o
00 0-O.1 0.0 SPECTRAL PERIOD, SEC.
Los Angeles, 09 Feb 81 Son Fernondo Earthquake after Campbell (1980).
Exomples of How Structures Without Basements Hove Higher Spectrol Accelerations thon
. tructures with Bosements
O 4
CL 0
CD 0
E 0
o 2
o Structure reducing motion Structure amplifying motion 0.01 0.1 IC SPECTRAL PERIOD, SEC, Damping = 5% ----
Hollywood Storage Bldg: Instrument at -
3m.
Humboldt Power Plant: Instrument at -
25m.
Pleasant Valley Pump Plant: Instrument at -
Sm.
Examples of How Structures Reduce Ground Motioh
- 4.
RESERVE CAPACITY
WE EXPECT MOST ENGINEERED STRUCTURES TO WITHSTAND SHAKING GREATER THAN THOSE FOR WHICH DESIGNED SOIL-STRUCTURE INTERACTION 1-1/2 - 2 DESIGN SAFETY FACTORS 2-4 RANGE OF EXPECTED EXCESS CAPACITY 3 -
8 I
0.30 0.20 -
An 0
z 0.10 o
D UO S0.05 0.03 A Maximum Acceleration on Roof O
Earthquake Response (No Structural Damage) 0.02 -
Earthquake Response (Structural Damage)
O1 Value used in Design 0.011 0.2 0.3 0.5 1
2 3
5 PERIOD (SECONDS)
Caoacity of Reinforced Concrete Structures Demonstrated During the San Fernando Earthquake
MAI'JAGUAKZ HICAAUA G12 115 POWERPLE1Y A~A CALLE CENTRAL PAN AMREY S
111 xoLoTLAN AP MNGANIAU NCGAGUAWNGTHLCAIOOF AIITEIN sUeLsNG REFERE1D7 SECNTASREPORUT 3
TAS1972 SEEO TABLEE
\\
O ITO TEFCLTE
1979 IMPERIAL VALLEY EARTHQUAKE EL CENTRO STEAM PLANT SIGNIFICANT CONCLUSIONS OF NUREG/CR-1665 0
"NOTEWORTHY IS THAT THE TWO OPERATING UNITS SAFELY SHUT DOWN AFTER HAVING EXPERIENCED A SEVERE SEISMIC ENVIRONMENT WHICH GENERALLY EXCEEDS THAT USED IN THE DESIGN OF NUCLEAR POWER PLANTS...
0 "MOST IMPORTANTLY THERE WERE NO KNOWN MALFUNCTIONS OF ELECTRICAL CONTROL AND INSTRUMENTATION EQUIPMENT" 0
"EXCEPT FOR BUCKLING OF A FEW MEMBERS IN THE BOILER SUPPORT FRAME, SIGNIFICANT STRUCTURAL DAMAGE WAS NOT OBSERVED" THE REPORT CONCLUDED THAT THIS CONDITION WAS "DISSIMILAR TO NUCLEAR APPLICATIONS."
OBSERVED DAMAGES TO ELECTRICAL FACILITIES FROM COALINGA EARTHQUAKE OF 02 MAY 1983, AND AFTERSHOCKS All owned by PGE (From Yanev et al.)
Epic PGA,g Dist (Tera)
Facility mile Med 84th Damage Observed Gates 14
.12
.19 Minor spilling of oil from large Sub.
transformers. One broken ceramic bushing on a transformer. Fallen ceiling tiles in control building.
No apparent structural damage.
Coalinga 10
.17
.25 Broken ceramic bushing on Sub. 1 transformer. Broken bolts on tranformer mounted on steel racks.
Sloshed oil from transformer.
No apparent structural damage.
Coalinga Sub. 2 1
.45
.67 Partial collapse of unreinforced block structure. Rupture of anchor bolts around transformers and subsequent sliding. Yielding of supports for rack-mounted transformers.
Transformer bolts were four @ 0.50-in. diameter.
SONGS criteria would have been four @ 1.125-in. diameter.
Stress ratio = (1.125/0.50)^2 = 5.1 1
SUMMARY
OF SOME OF CONSERVATISMS IN SONGS 1 DESIGN
- 1.
O.5G IS 1 SIGMA VALUE
- 2.
RETURN PERIOD FOR 0.5G IS 105 TO 106 YEARS
- 3.
0.67G IS A 2 SIGMA VALUE
- 4.
RETURN PERIOD FOR O.67G IS 106 TO 107 YEARS
- 5.
SOIL STRUCTURE INTERACTION EFFECTS CONSERVATIVELY CONSIDERED
- 6.
EARTHQUAKE PERFORMANCE SHOWS STRUCTURES AND COMPONENTS HAVE CONSIDERABLE RESERVE CAPACITY
SEISMIC RISK THIS TASK CONSISTS OF AN ATTEMPT TO ASSESS THE SEISMIC RISK AT SONGS 1 BASED ON THE RESULTS OF PROBABILISTIC RISK ASSESSMENTS DONE AT OTHER PLANTS.
SITE SPECIFIC EARTHQUAKE RECURRENCE DATA WILL BE UTILIZED.
APPROACH 0
APPROACH ASSESS SONGS 1 DESIGN AGAINST DOMINANT CONTRIBUTORS TO SEISMIC CORE MELT FREQUENCY 0
METHODOLOGY REVIEW PUBLISHED SEISMIC PRA'S
~IDENTIFY DOMINANT CONTRIBUTORS TO SEISMIC CORE MELT FREQUENCY STATUS SONGS 1 DESIGN
PRA DOMINANT CONTRIBUTORS TO CORE MELT FREQUENCY 0
ONSITE POWER DIESEL GENERATOR SUPPORT SYSTEMS POWER AND CONTROL ANCHORAGE RACEWAYS 0
ESSENTIAL WATER SUPPLIES LARGE TANKS 0
STRUCTURES CLOSELY.SPACED STRUCTURES LIMITED STRUCTURAL DISTRESS MASONRY WALLS CONTROL ROOM CEILING 0
REACTOR COOLANT SYSTEM SUPPORTS ENCLOSING STRUCTURES
SONGS 1 STATUS PRA DOMINANT CONTRIBUTORS TO CORE MELT FREQUENCY 0
ONSITE POWER DIESEL GENERATOR SUPPORT SYSTEMS:
DESIGNED TO.67G POWER AND CONTROL ANCHORAGE:
MODIFIED TO.67G RACEWAYS:
80% MODIFIED TO.67G; TESTS 0
ESSENTIAL WATER SUPPLIES LARGE TANKS:
NEW AFWT AND CONNECTION TO SPENT FUEL POOL DESIGNED TO.67G 0
STRUCTURES CLOSELY SPACED STRUCTURES: ACCEPTABLE FOR.67G LIMITED STRUCTURAL DISTRESS:
ANALYZED AND/OR MODIFIED TO.67G MASONRY WALLS:
TESTED AND/OR MODIFIED TO.67G CONTROL ROOM CEILING:
MODIFIED TO.67G 0
REACTOR COOLANT SYSTEM SUPPORTS:
ANALYZED AND MODIFIED TO.67G ENCLOSING STRUCTURES:
ACCEPTABLE FOR.67G
PIPING SYSTEMS 0
DUCTILE PIPING NOT A DOMINANT CONTRIBUTOR 0
IDENTIFIED PROBLEMS GENERALLY LIMITED TO NON-DUCTILE PIPE THREADED PIPE PIPING ROUTED BETWEEN BUILDINGS 0
PIPING IN SAFETY RELATED SYSTEMS AT SAN ONOFRE IS DUCTILE AND DOES NOT HAVE FIRST TWO PROBLEMS; PIPING ROUTED BETWEEN BUILDINGS WILL BE SPECIFICALLY ADDRESSED.
SEISMIC PRA CONCI US1ONS RELATIVE TO SAN ONOFRE 0
SIGNIFICANT SEISMIC UPGRADE WORK HAS BEEN DONE ON ALL DOMINANT CONTRIBUTORS 0
PIPING IS NOT SIGNIFICANT CONCERN WITH RESPECT TO RISK
SAFL SHUTDOWN 0
SAFE SHUTDOWN SYSTEMS 0
ACCEPTABILITY CRITERIA O
SYSTEM REVIEW
SAFE SHUTDOWN SYSTEMS THIS TASK CONSISTS OF IDENTIFYING THE LIST OF SYSTEMS AND EQUIPMENT WHICH WOULD BE REQUIRED TO SAFELY SHUT DOWN THE PLANT TO HOT STANDBY (MODE 3) FOLLOWING AN EARTHQUAKE.
SAFE SHUTDOWN SYSTEMS 0
REACTOR COOLANT PRESSURE BOUNDARY 0
MAIN STEAM AND FEEDWATER LINES 0
CHARGING 0
AUXILIARY FEEDWATER OR RECIRCULATION
ACCEPTABILITY CRITERIA THIS TASK CONSISTS OF DEVELOPMENT OF CRITERIA CONSISTENT WITH ANALYSIS MARGINS AND EARTHQUAKE EXPERIENCE TO BE USED IN RETURN TO SERVICE EVALUATION.
THE ACCEPTABILITY CRITERIA WILL CONSIDER THE FOLLOWING:
- 1.
REDUCTION OF IN-STRUCTURE RESPONSE.
- 2.
USE OF HIGHER DAMPING FOR ALL SIZES OF PIPING.
- 3.
ALTERNATIVE METHOD TO THE USE OF BROADENED RESPONSE SPECTRA IN PIPING ANALYSIS.
- 4.
FUNCTIONALITY STRESS LIMITS FOR PIPING AND PIPE SUPPORTS.
- 5.
USE OF INELASTIC CRITERIA FOR THE EVALUATION OF STRUCTURES.
- 6.
FOR SMALL PIPING, USE OF TEST DATA AND WALKDOWNS.
2.0 I.8 I,7 1.6 1.5 1,.4 S A BPC DESIGN 1.2
-SPECTRUM 1.2 (g's)I.1 HOUSNER PIPING 1.0 0.9 0.7 IBPC DESIGN 0.6 _
SPECTRUM 0.5 0.4 0.3 LLNL 0.2 0.1 0.1 1.0 10.0 100.0 FREQUENCY (He)
I CONTAINMENT FOUNDATION RESPONSE SPECTRA 1.TAKEN FROM LLNL DRAFT REPORT DATED JUNE 18,1982
USE OF 5% DAMPING 0
RECOMMENDED BY PVRC:
.5%
R.G. 1.61
/
=10 HZ 0
BASED ON EXPERIMENTAL RESULTS 0
MORE VALID AT HIGHER STRESS LEVELS
APPLICATION OF SPECTRA SHIFTING 0
BROADENING ACCOUNTS FOR UNCERTAINTY IN LOCATING PEAK 0
ALTERNATE:
f(e) 0 BASIS IN SRP 3.9.2
FUNCTIONALITY CRITERIA 0
PIPE STRESS ALLOWABLES P + WT + SSE 2a 2
FOR CARBON STEEL P + WT + SSE &2.2a FOR STAINLESS STEEL 0
PIPE SUPPORT QUALIFICATION SYSTEM EVALUATION -BASED ON ENERGY BALANCE APPROACH.
CURRENT STATUS
- 0.
LINES ANALYZED 204/250 0
LINES WITH NO RELIANCE ON CRITERIA 124 0
LINES WITH LIMITED RELIANCE ON CRITERIA 37 0
LINES WITH MODERATE RELIANCE ON CRITERIA 27 0
LINES WITH SIGNIFICANT RELIANCE ON CRITERIA 16.
STRUCTURAL MEMBERS 0
EVALUATION OF STRUCTURES SUBJECTED TO REACTION FROM LARGE BORE PIPING 0
EFFECTS ON STEEL MEMBERS 0
CONNECTIONS CHECKED AGAINST YIELD AND REQUIRED CAPACITIES OF CONNECTED MEMBERS 0
STRUCTURAL MEMBERS TO PLASTIC DESIGN LIMITS OF "BOP STRUCTURES SEISMIC REEVALUATION PROGRAM, TURBINE BUILDING AND TURBINE GENERATOR PEDESTAL," APRIL 30, 1982 0
SECONDARY STEEL MEMBERS PIPING LOADS EXISTING STRESSES CRITERIA WILL BE BALANCE OF PLANT STRUCTURES SEISMIC REEVALUATION CRITERIA, FEBRUARY 1981
INHERENT CONSERVATISMS -
PIPING SYSTEM 0
STRAIN RATE EFFECTS 0
STRESS.INTENSIFICATION AND FLEXIBILITY FACTORS IN YIELDING COMPONENTS 0
INCLUSION OF PRESSURE EFFECTS 0
COMPONENT THICKNESSES AND MATERIAL STRENGTHS
. 0 USE OF ASME COLLAPSE MOMENT
INHERENT CONSERVATISMS -
INPUT MOTION 0
PGA IS 2 SIGMA EVENT 0
EFFECTS OF EMBEDMENT 0
SOIL STRUCTURAL INTERACTION EFFECTS 0
COUPLING OF PIPING AND STRUCTURES 0
TIME HISTORY ENVELOPES DESIGN SPECTRUM
SYNTHETIC TIME HISTORY SPECTRUM 1.00 DESIGN SPECTRUM'
_j Q5
.PERIOD
. DES/6 l T7/4
/HSTORY(4%)
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