ML18149A164
| ML18149A164 | |
| Person / Time | |
|---|---|
| Site: | Surry  |
| Issue date: | 05/19/1986 |
| From: | Chan T Office of Nuclear Reactor Regulation |
| To: | Office of Nuclear Reactor Regulation |
| References | |
| TAC-59821, TAC-59822, NUDOCS 8605300316 | |
| Download: ML18149A164 (38) | |
Text
-
May 1 9, 1 986 e
"\\
DISTRIBUTION Docket Nos. 50-280/281 Docket Fi 1 e E. lJordan NRC PDR B. Grimes Local PDR ACRS (10)
PAD#2 Rdg E. Sullivan APPLICANT:
FACILITY:
SUBJECT:
Virginia Electric and Power Company Surry Power Station, Units 1 and 2 MEETING
SUMMARY
REGARDING THE DECEMBER A PARTIAL EXEMPTION FROM GDC-4 J. Partlow R. Klecker T. Chan R. Ballard C. Patel R. Licciardo OELD G. Baqchi 19, 1985 MEETING ON S. Hou H. Brammer J. Rajan A meeting was held in Bethesda, Maryland with Virginia Electric and Power Company and NRR representatives on December 19, 1985 to dicuss VEPCO's November 5, 1985 and December 3, 1985 submittals regarding a "narrow scope" exemptions from GDC-4.
A list of attendees is provided in Enclosure 1.
The technical discussions centered on RCS piping loads RCS leakage detection and the safet.v balance evaluations. The staff identified five areas within
- the RCS piping load analysis for which additional information was required.
VEPCO reiterated these questions in a "letter of understanding dated December 27, 1985.
Their responses to these questions were provided in a letter dated January 14, 1986.
A copy of the VEPCO presentation handouts is included in Enclosure 2.
Enclosures:
As stated cc:
See next page PM:%l3 ~#2 TChan:bl 5/ /5/86 r-<:,l,LSRubenstein t9Plk/5! f\\/86
- -- ~-- ------ -
8605300316 860519 PDR ADOCK 05000280 P
PDR Terence L. Chan, Project Manager PWR Project Directorate #3 Division of PWR Licensing-A Office of Nuclear Reactor Regulation
Mr. W. L. Stewart Virginia Electric and Power Company cc:
Mr. Michael W. Maupin Hunton and Williams Post o~¥ice Box 1535 Richmond, Vir9inia 23213 Mr. Robert F. Saunders, Manager Surry Power Station Post Office Box 315 Surry, Virginia 23883 Resident Inspector Surry Power Station U.S. Nuclear Regulatory Commission Post Office Box 166, Route 1 Surry,. Virginia 23883 Mr. Sherlock Holmes, Chairman Board of Supervisors of Surry County Surry County Courthouse Surry, Virginia 23683 W. T. Lough Virginia Corporation Commission Division of Energy Regulation Post Office Box 1197 Richmond, Virginia l3209 Mr. J. T. Rhodes Senior Vice President - Power Virginia Electric and Power Company Post Office Box 26666 Richmond, Virginia 23261 Re~ional Administrator, Region II U.S. Nuclear Requlatory Commission 101 Marietta Street, Suite 3100
. Atlanta, Georgia 30323 James R. Kenle.v, M.D., Commissioner Department of Health 109 Governor Street Richmond, Virginia
~3?.19 Surry Power Station Attorney General Supreme Court Building 101 North 8th Street..
Richmond, Virginia 23219
e ATTENDANCE LIST PAPTIAL EXEMPTION TO GDC-4 SURRY POWER STATION DECEMBER 19, 1985 NRC-NRR L Chan E. Sullivan R. Klecker R. Ballard R. Licciardo G. Bagchi
- s. Hou H. Brammer J. Rajan Paul Munroe Energy Plants W. Norwood Stone & Webster A. Banersee VEPCO r Robinson, Vo K. Dwivedy H. Miller E. Schaub -
B. Dunlap D. Christian M. Whitt J. Hegner R. MacManus N. Clark Westinghouse
<1. Mc I nerney E.,Johnson Jr.
60-RKM-3426B-1 e
e ENCLOSURE 2 PRESENTATION BY VIRGINIA ELECTRIC AND POWER COMPANY MEETING TO DISCUSS A PARTIAL EXEMPTION FROM GDC-4 SURRY POWER STATION UNITS 1 AND 2 Bethesda, Md.
Room P-114 Phillips Building December 19, 1985
e e
AGENDA 9:00 A.M.
I.
INTRODUCTORY REMARKS T. Chan, NRC IDENTIFICATION OF ATTENDEES 9: 05 A. M*.
I I.
PURPOSES OF MEETINGS J. D. Hegner, VEPCO 9:10 A.M.
III. REVIEW OF PREVIOUS DOCUMENTATION J. D. Hegner, VEPCO 9:15 A.M.
IV.
SUMMARY
OF TECHNICAL ISSUES R. K. MacMr1nus, VEPCO A. Loading Evaluation B. Leak-Detection System Evaluation C. Safety Br1lance Assessment 10: 00 A. M.
V.
SUMMARY
Ll
- D. Heqner, Vepco 10:15 A.M.
VI.
ADJOURN 60-RKM-3426B-30
e e
II. PURPOSES OF MEETING
¢RIMARILY TECHNICAL: IDENTIFY POSITIONS OF VEPCO AND REMAINING QUESTIONS BY NRC OBJECTIVES:
TECHNICAL 60-RKM-3426B-3
- 1) ASSURE NRC UNDERSTANDS CURRENT VEPCO POSITION
- 2) IDENTIFY ANY NEW AREAS OF CONCERN AND POTENTIAL RESOLUTION SCHEDULAR
- 1) RESOLVE ANY TECHNICAL ISSUES ~/ITH NRC BY mo OF JANUARY, 1986 TO SUPPORT VEPCO PLANNING ACTIONS
- 2) OBTAIN FORMAL ~RC APPROVAL DURIMG MARCH, 1986
0 0
0 60-RKM-3-1268-4 e
BA.CKGROUND BASED UPON GENERIC LETTER 84-04 DYNAMIC EFFECTS OF MAIN RCS PIPE RUPTURE CAN BE EXCLUDED FROM DESIGN BASE.
18 LARGE BORE SNUBBERS PER UNIT DESIGNED PRIMARILY TO CARRY MAIN RCS PIPE RUPTURE LOADS CAN BE ELIMINATED TO:
0 IMPROVE PLANT RELIABILITY 0 REDUCE FUTURE OCCUPATIONAL RADIATION EXPOSURE 0 ENHANCE PLANT MAINTAINABILITY 0 REDUCE FUTURE COSTS ANALYSES HAVE BEEN PERFORMED TO ENSURE ADEQUATE SAFETY MARGINS EXIST WITH REVISED SUPPORT SYSTEM.
e*
III. REVIEW OF PREVIOUS DOCUMENTATION DOCUMENT A.
WESTINGHOUSE GENERIC SUBMITTAL WCAP-9558 (Rev. 2)
WCAP-9787 (Rev. 0)
B.
NRC GENERIC LEITER 84-04 C.
VEPCO LETTER TO NRC REQUESTING PARTIAL EXEMPTION FROM GDC-4 D.
VEPCO LETTER TO NRC PROVIDING 0 RCS PIPING LOADS EVALUATION 0 RCS LEAKAGE DETECTION SYSTEM EVALUATION 0 SAFETY BALANCE VALUE IMPACT ASSESSMENT DATE MAY, 1981 FEB. 1, 1984 NOV. 5, 1985 DEC. 3, 1985 NOTE:
REPORTS IN 11A 11 WERE SPONSORED BY ~/ESTINGHOUSE USI A-2 O~JNERS GROUP 60-RKM-3426B-5
'J
0 0
0 0
0 0
60-RKM-34268-6 e
I II A.
PRINCIPAL CONCLUSIONS OF WCAP-9558 AND WCAP 9787 EXTENSIVE OPERATING EXPERIENCE HAS DEMONSTRATED THE INTEGRITY OF W PWR RCS LOOP PRE-SERVICE AND IN-SERVICE INSPECTIONS OF RCS PIPING MINIMIZE POSSIBILITY OF FLAWS EXISTING IF A LARGE T~ROUGH-WALL FLAW IS
-POSTULATED,-LARGE MARGINS EXIST AGAINST UNSTABLE CRACK GROWTH DOUBLE ENDED GUILLOTINE BREAK OF RCS PRIMARY PIPING HAS LOW PROBABILITY.
LEAKAGE DETECTION SYSTEM CAN IDENTIFY FLAW GROWTH LONG BEFORE IT BECOMES UNSTABLE.
CONTROLLED REACTOR SHUTDOWN WILL OCCUR BEFORE PIPE WOULD FAIL IN A CATASTROPHIC MANNER.
e*
VEPCO LETTER TO NRC OF NOV. 5, 1985 SCOPE OF REQUEST:
APPROVAL OF THIS EXEMPTION WILL ALLOW VEPCO TO REDESIGN THE RCS EQUIPMENT RESTRAINT SYSTEM IN ORDER TO:
IT I B.
0 ELIMINATE EIGHTEEN LARGE BORE HYDRAULIC SNUBBERS PER UNIT CURRENTLY RESTRAINING THE REACTOR COOLANT PUMPS AND STEAM GENERATORS.
0 ELIMINATE NEED FOR A-2 BACKFIT MODIFICATIONS.
GRANTING REQUEST WOULD NOT AFFECT:
0 ECCS DESIGN BASIS.
0 REACTOR BUILDING AND COMPARTMENT DESIGN.
0 EQUIPMENT QUALIFICATION BASIS.
0 ENGINEERED SAFETY FEATURE SYSTEMS RESPnNSE.
60-RKM-3426B-7
e IV.
SUMMARY
OF TECHNICAL ISSUES THE FOLLOWING EVALUATIONS WERE SUBMITTED BY VEPCO ON DEC. 3.
A.
LOADH!G EVALUATION B.
LEAKAGE DETECTION SYSTEM EVALUATION C.
SAFETY BALANCE ASSESSMENT 60-RKM-342fiB-8
0 0
60-RKM-34268-9 e
LOADING EVALUATION OBJECTIVES VERIFY FRACTURE MECHANICS EVALUATION PERFORMED FOR NRC USI A-2 OWNERS GROUP IS STILL VALID.
VERIFY THAT REACTOR COOLANT SYSTEM, EQUIPMENT, PIPIN& AND SUPPORTS HAVE ADEQUATE MARGINS OF SAFETY.
IV. Al
e REACTOR~ VESSEL 12 11 LOWER PATHONS (4/LOOP)
STEAM GENERATOR FIGURE l LARGE BORE SNUBBER CONFIGURATION PER LOOP RC PUMP 4
11 -BERGEN-PATERSONS (4/PUMP) 12 11 -BERGEN-PATERSONS (2/LOOP)
I Four 4 11-bore Bergen-Paterson snubbers to be eliminated e
FIGURE 2 Page 1 of 2 REACTOR COOLANT PUMP SUPPORTS GENERAL ARRANGEMENT SURRY POWER STATION 1
I
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I
_JC I
__,.21,._'*...:D'_.(D=ffJ....l,QuPS "°ill--t--1------__J
...£.1...A..!i.
~.. D "At. - J LOOf'S Two 12 11 -bore
~erqen-Paterson snubbers to be eliminated
Four 4 11-bore Bergen-Paterson snubbers to be*
eliminated
\\
FIGURE 2 Page 2 of 2 I
I r* :L-l -- -**-.
I REACTOR COOLANT PUMP SUPPORTS GENERAL ARRANGEMENT SURRY POWER STATION spg UFSAR Fir,urr. 15.fi-3
- [.&CTOIII L.;.....;.----eooL&IIT "u**
,..0N08AU. A5.SEMALT I
r-PoPll ~~........,... (n.*!,'!> )
t ____ L __ _j ELE:-V C.*C Two 12 11 -bore
~ergen-Paterson snubbers to be eliminated
II I
I 1*
I I
LJ FIGURE 3 P~ge 1 of 2
- \\~,.Vi'.
i Four 12"-bore I Pathon snubbers STEAM GENERATOR SUPPORT ASSEMBLY SURRY* POWER STATION SPS UFSAR Figure 15.6-2 I L,a
.* r 1,A
.1.1-._*
/
1 to be maTafoed __ -l Y
""'--OIi-.-. ('~,-----==---:_i-:-~-.-:-:-: -
[F.
I:
r - !
l.:. -
'*i I
I
~
-==-==---
cs.*-
I
~ 1 L!:Ji'.:j" (,...:!!U.....
( ii: *!'*i*
I I !
)
j I
I i,j
!"'I... in Four 12 11 -bore Pathon snubbers to be eliminated ELEVA.TICN QIW
- T1
... 0
- '~-~
/
/,
I
- I I_,.....-....,
/
- ta 1
\\
_...--14
II II 2
A-A FIGURE 3 Page 2 of 2
-- 17
!!'-o' "O lltEACT~ i 22 G
8-B STEAM GENERATOR SUPPORT ASSEMBLY SURRY POWER STATION SPS UFSAR Eigure 15.6-2 Four 12 11 -bore Pathon snubbers to be maintained Four 12"-bore Pathon snubbers to be eliminated
&1111**'- ao,u ICA\\.f 111*
- 1*-0*
J,, 11* 1u*.-o*n *ro*o,oa tac* ua*"
0 0
0 MATHEMATICAL MODELS ESSENTIALLY TWO INDEPENDENT MATHEMATICAL MODELS WERE PREPARED BY SWEC AND W EACH MODELED A SINGLE LOOP COMPLETELY MODELS INCORPORATED UP TO DATE GEm1ETRY AND PROPOSED SUPPORT CONFIGURATION.
0 SUPPORT STIFFNESS DEVELOPED IN THE SWEC MODEL (FIG. 4) WAS USED IN THEW MODEL (FIG. 5) 60-RKM-34268-10 IV. A2
Of LOOP' l~CJ
,lAH[*ltLAh[
. 9 :~; or NOf UG l*i OP OPV
- 9
@..,.-0----
92 MAIN STf:J~~~I toted
'sc; Ii. lor loop 21
'E:!::JI o,'5 0
59 SNUB8[R OR IIIAINFW NOZZLE
(!>
SUCTION LINE 0----0 u.l I SHOWN Rtl(,v~rs MO MllolU[N I,.._I>
NO:I All NOT A 5NUDUI R 0 l'IN-[ND[D, f[OUIIIL *Nt T
,arrr*,.,~..
rnnt1n,.,. *,r t4ebster Model stone:&.
/Structural for P1prnq Analysis
.AAOTN[ MODCL
- swcc ST roR
- .N.AL n,s II ll(OUCTION
'INUBD[
52 SG UPPER SUPPORT 51 50 L
>- 18 17 16 5
SG LOWER SUPPORT -
14 RCP SUPPORT 20 9 l3 RCP 80 21 22 82-23 81, 25 33 ~
24 37 97 32 35 31 27 26 30 28 29 36 SG y
z)-x 100 9 7 5
4 3 2 1 8 6 RPV
~-~___; __________ _..,.1001 101 40 42 44 41 43.
39 98 38 99 WESTINGHOUSE MODEL FOR PIPING ANALYSIS e
0 0
0 0
0 60-RKM-3426B-11 e
LOADING CONDITIONS DEADHEIGHT THERMAL EXPANSION INTERNAL PRESSURE SEISMIC EVENTS (OBE & DBE)
DYNAMIC EFFECTS OF LIMITING PIPE RUPTURES OF PRESSURIZER SURGE, MAIN STEAM, &
FEEDl*JATER LINES IV. A3
0 0
COMPUTER PROGRAMS STARDYNE VERSION 3, LEVEL H.
STAR (STATIC AND ~ODAL EXTRACTION)
DYNRE 4 (RESPONSE SPECTRUM)
DYNRE 6 (TRAMSIENT ANALYSIS)
. PUBLIC. DOMAIN DOCUMENTED MAINTAINED BY SWEC QA HESTDYN ACCEPTABLE BY NRC FOR SURRY-1974 MAINTAINED BY WESTINGHOUSE QA 60-RKM-3426B-12 IV. A4
IV. A5 CODES AND STANDARDS 0
ANSI B31.1 PIPING 0
ASME BOiLER AND PRESSURE VESSEL CODE SECTION III - EQUIPMENT 0
UFSAR FOR SURRY POWER STATION 60-RKM-3426B-13
e IV; A6 MAXIMUM STRESSES IN RCS PIPING LEVEL OF STRESS AS% OF 831.1 CODE ALLOWABLE LOADING THERMAL PRESSURE
+ DEADWEIGHT PRESSURE
+ DEADWEIGHT
+ OBE PRESSURE
+DEAm*JEIGHT
+DBE S = 15 Ks i h
HOT LEG
- 38. 6~~
68.0%
- 65. 6~.;
49.6%
CROSSOVER LEG 15.6%
48.7%
51.1%
COLD LEG 7.4%
53.3%
60.0%
48.9%
NOTE:
THE HIGHEST PERCENTAGE OF STRESS/ALLOWABLE STRESS IS FOR HOT LEG PRESSURE+ DEADWEIGHT.
60-RKM-3426B-14 CODE ALLmJ-ABLE 1.0\\
1.2\\
1.8\\
e e
IV. A7 GENERIC FRACTU~E MECHANICS EVALUATIONS ARE STILL VALID LOADS CONSIDERED:
.0 DEAD\\~EIGHT 0
PRESSURE 0
- THERMAL 0
DESIGN BASIS EARTHQUAKE (MOST SEVERE SEISMIC CASE)
FORCES AXIAL FORCE MOMENTS 60-RKM-3426B-15 SURRY UNITS ANALYSIS 1,685 KIPS 28,860 IN KIPS w
GENERIC ANALYSIS WCAP-9558 1,800 KIPS NRC GENERIC LETTER 84-04 45,000 IN KIPS 42,000 IN KIPS
0 0
0 0
0 0
0 e
IV. A.8
- LOADING COMBINATIONS FOR COMPONENT SUPPORT DtSIGN PRESSURE+ DEADWEIGHT + THERMAL PRESSURE+ DEADWEIGHT +THERMAL+ OBE PRESSURE+ DEADWEIGHT +THERMAL+ DBE PRESSURE+ DEADWEIGHT +THERMAL+ (SRSS OF DBE AND PIPE RUPTURE)
COMPONENT AND COMPONENT SUPPORT RESULTS COMPONENT SUPPORT STRESSES ARE WITHIN UFSAR ALLOWABLES STEAM GENERATOR AND RC PUMP FOOT/SUPPORT INTERFACE LOADS ARE WITHIN ALLOWABLE EQUIPMENT NOZZLE LOADS ARE WITHIN ALLOWABLE 60-RKM-3426B-16
TABLE 1 FACTORS OF SAFETY FOR COMPONENT SUPPORTS UNDER SEISMIC LOADS COMPONENT Steam Generator Shell/
Support Interface SteaM Generator Upper Support Component Upper Guides Snubbers Steam Generator Lower Support Hanger Rod Swivel End Coupling Steam Generator Foot Vertical Force Tangential Force RC Pump Foot Vertical Force Tangenti a 1 Force Radial Force RC Pump Support Upper Vertical Upper Horizontal Lower_ Vertical Lo\\'ter Di agonti l FACTOR OF SAFETY*
40.7 17.4 7.3 14.2 2.3 16.9 3.1
- 15. 7 5.8 20.6 22.1 7.1 7.1 5.3 6.1 (min.)
Allowable Load
- Factor of Safety=
Total Load of Deadweight +Pressure+ DBE.
60-RKM-3426B-17
__J
r 0
0 e
ADDITIONAL CONSERVATISMS DAMPING VALUES 0.5% QBE, 1% DBE USED.
INSTEAD OF REG. GUIDE 1.61 OR CODE CASE N411 COMPARISONS BASED ON ELASTIC LIMITS ARE NOT A TRUE INDICATOR OF FAILURE 60-RKM-34268-18 IV. A9
t' I
0 0
0 INDEPENDENT VERIFICATION TWO ESSENTIALLY INDEPENDENT ANALYSES OF ONE COMPLETE LOOP.
THE RESULTS OF BOTH ANALYSES AT SUPPORT TO COMPONENT INTERFACE WERE IN ACCEPTABLE AGREEMENT.
INTERFACES ARE SHOWN IN FIG. 6 60-RKM-34268-19 IV. AlO
SEISMIC EXISTING PIPING
-1 MODEL E SPEC I
ALLOWABLES - -I FOR £QUIP.
I EXISTING
~I SSI ARS EXISTING PRIMARY L MODEL I
1 COMPONENT J SUPPORT A LLOWABL.fS PIPE RUPTURE DEFINITION OF INTERFACE DEFINITION Of INTERFACES MODIFY MODEL FLUID
_. DYNAMIC*
MODEL F~UID l-t, DYNAMIC
, MODEL UPDATE MODEL GENERATE H
STlfftJESS MATRIX SURGE LINE FORCING FUNCTIONS MS & FDW FORCING --t P'
FUNCTIONS COMPARISON
... ANALYSIS ro ALLOWABLES w
COMPARISON AT INT FAC COMPARrSON
~ ANALYSIS TO -
SWEC ALLOWABLES w
COM~RISON TO ALLOWABLES
.~
r ANALYSIS COMPARISON LOAD COM~RISON OF TO
._. INTERFACE 1-t TO BREAKS ALLOWABLES
SUMMARY
ALLOWABLES SWEC G
C
- 0 rn 6'
t 0
0 0
QUALITY ASSURANCE ANALYSES PERFORMED AND REVIEWED AS CATEGORY 1 CALCULATIONS WORK PERFORMED UNDER 10 CFR 50 APPENDIX B QUALITY ASSURANCE PROGRAM RESULTS ARE MAINTAINED IN PROJECT DOCUMENT CONTROL 60-PKM-3426B-20 IV. All
0 0
0 LOADING EVALUATION CONCLUSIONS PIPING, COMPONENTS AND SUPPORTS ARE STRESSED WITHIN UFSAR ALLOWABLE LIMITS ADEQUATE SAFETY MARGINS EXIST; STRUCTURAL INTEGRITY WILL BE MAINTAINED DURING SEISMIC EVENT MAXIMUM MOMENT IN REACTOR COOLANT PRIMARY PIPING IS WITHIN THE ENVELOPE MOMENT OF GENERIC LETTER 84-04.
60-RKM-34268-21 IV. A12
0 e
IV. Bl LEAKAGE DETECTION SYSTEM EVALUATION OBJECTIVE VERIFY THAT THE SURRY RCS LEAKAGE DETECTION SYSTEMS HAVE AN ACCEPTABLE CAPABILITY OF DETECTIMG A 1 GPM LEAK IN 4 HOURS.
SUMMARY
" 0 THE ATTACHMENrTO VEPCO LETTER OF-DEC. 3, 1985 REVIHJS THE SURRY RCS LEAKAGE DETECTION SYSTEM VS. THE NINE DESIGN GUIDELINES OF REG.
GUIDE 1.45.
0 CONCLUSION THE LEAKAGE DETECTION CAPABILITY AT SURRY MEETS THE INTENT OF THE GUIDELINES OF REG. GUIDE 1.45.
0 THE LEAKAGE DETECTION SYSTEMS AT SURRY ARE CAPABLE OF DETECTING A 1 GPM LEAK.IN 4 HOURS.
60-RKM-3426B-22
0 0
e IV. Cl SAFETY BALANCE ASSESSMENT ANALYSES USED METHODS OF SAFETY BALANCE AS PROVIDED IN GENERIC LETTER 84-04 EXPOSURE DATA FOR REMOVAL AND REirlSTALLATION OF LARGE BORE SNUBBERS FOR FUNCTIONAL TESTING/SEAL REPLACEMENT IS BASED ON ACTUAL EXPOSURE DATA FROM 1984 AND 1985 OUTAGES.
0 DOES 'NOT TAKE CREDIT FD~ MANY ASPECTS WHICH ARE NOT EASILY QUANTIFIABLE 60-RKM-3426B-23
A l
' I
~
~
e IV. C2 SAFETY BALANCE VALUE
SUMMARY
VALUE (MAN-REM)
LOWER Not1INAL UPPER ESTIMATE ESTIMATE *
- ESTIMATE PUBLIC HEAL TH 0.0
-0.56
-5.94 OCCUPATIONAL EXPOSURE 0.0
-0.11
-3.67 (ACCIDENTAL)
OCCUPATIONAL -EXPOSURE (ROUTINE)
(a) DUE TO ELIMINATING BACK-FIT 122 366 1098 MODIFICATIONS FOR ASYMMETRIC PRESSURE (UNITS 1 AND 2)
(b) DUE TO ELIMINATING REMOVALS AND
,. REINST.ALLATIONS OF 18 SNUBBERS (UNIT 1) 728 1520 3036 (UNIT 2) 242 507 1518 (c) DUE TO ELHHNATHIG VISUAL 19 27 54 INSPECTIONS OF 18 SNUBBERS (UNITS 1 AND -2)
(d) DUE TO ELIMINATING IMPACT ON 15 20 30 OTHER ITEMS BY REMOVAL OF 18 SNUBBERS (UNITS 1 AND 2)
TOTAL QUANTIFIED VALUE 1126 2439 5726 POSITIVE VALUE~= EXPOSURE DECREASE; NEGATIVE VALUES= EXPOSURE INCREASE CONCLUSION:
BENEFITS FAR EXCEED RISK 60-RKM-34268-24
< I lo 0
0 0
0 0
e ENHANCEMENT OF RELIABILITY REMOVAL OF SNUBBER CAN ENHANCE RELIABILITY AS DISCUSSED IN NUREG/CR-3718.
ELIMINATES POTENTIAL FOR INADVERTENT LOCK-UP OF SNUBBERS.
REDUCING THE NUMBER OF LARGE BORE SNUBBERS ALLOWS BETTER MAINTEN_M!CE OF THE REMAHJING SNUBBERS.
THOSE SNUBBERS TO BE RETAINED WITH THE PROPOSED MODIFICATION WILL BE IN THE MORE ACCESSIBLE AND LOWER RADIATION AREAS AND CAN BE MAINTAINED MORE EASILY.
CONSIDERING FUTURE PROGRAM TO REFURBISH SNUBBERS WITH:
0 0
0 0
INDIVIDUAL RESERVOIRS SEALS WITH LONGER SERVICE LIFE SELF FLUSHING AND MORE RELIABLE CONTROL VALVE TEST-IN-PLACE CAPABILITY 60-RKM-3426B-25 e
IV. C3
... vJ t..i
(
t,
/1
- 1.
-~ 2.
e V.
SUMMARY
LOADING EVALUATION:
0 MAXIMUM MOMENT IN THE RC PRIMARY PIPING IS WITHIN THE ENVELOPE MOMENT OF BOTH THE WCAP-9558 AND GENERIC LETTER 84-04.
0 PIPIMG, COMPO~ENTS AND SUPPORTS.
ARE STRESSED WITHIN UFSAR ALLOWABLE LIMITS.
0 ADEQUATE SAFETY MARGINS EXIST.
LEAKAGE DETECTION SYSTEM EVALUATION:
0 0
SURRY IS CAPABLE OF DETECTING A 1 GPM LEAK IN 4 HOURS.
SURRY MEETS THE INTENT OF REG.
GUIDE 1.45.
- 3.
SAFETY BALANCE ASSESSMENT:
0 0
60-RKM-34268-31 MAN-REM EXPOSURE BENEFITS FAR EXCEED THE RISK.
REMOVAL OF THE SNUBBERS ENHANCES SURRY'S RELIABILITY
V.
SUMMARY
- 1.
NRC AGREEMENT TO RESOLUTION OF TECHNICAL ISSUES BY END OF JANUARY, 1986 TO SUPPORT VEPCO PLANNI~G ACTIONS.
- 2.
NRC FORMAL RESPONSE TO VEPCO LETTER OF NOV. 5, 1985 (REQUESTING PARTIAL EXEMPTION FROM GDC-4) NEEDED DURING
- MARCH, 1986.
60-RKM-34268-32
.J