ET-NRC-93-4027, Forwards Responses to RAIs on AP600 from NRC
| ML20058K519 | |
| Person / Time | |
|---|---|
| Site: | 05200003 |
| Issue date: | 12/09/1993 |
| From: | Liparulo N WESTINGHOUSE ELECTRIC COMPANY, DIV OF CBS CORP. |
| To: | Borchardt R NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| ET-NRC-93-4027, NUDOCS 9312150269 | |
| Download: ML20058K519 (42) | |
Text
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Westinghouse Energy Systeras 82 355 Pittsburgh Pennsylvama 15230 f)355 Electric Corporation ET-NRC-93-4027 NSRA-APSI 93-0487 Docket No.: STN-52-003 i
i December 9,1993 Document Control Desk i
U.S. Nuclear Regulatory Commission i
Washington, D.C. 20555 ATTENTION:
R.W.BORCHARDT
SUBJECT:
WESTINGHOUSE RESPONSES TO NRC REQUESTS FOR ADDITIONAL INFORMATION ON THE AP600 i
Dear Mr. Borchardt:
Enclosed are three copics of the Westinghouse responses to NRC requests for additional information f
on the AP600 from your letter of Septernber 23,1993. This transmittal completes the responses to that letter. Revisions to responses previously transmitted are also included. A listing of the NRC j
requests for additional information responded to in this letter is contained in Attachment A.
i These responses are also provided as electronic files in Wordperfect 5.1 fonnat with Mr. Hasselberg's copy.
If you have any questions on this material, please contact Mr. Brian A. McIntyre at 412-374-4334.
I W As.-
Nicholas J. Liparulo, Manager Nuclear Safety & Regulatory Activities
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I ET-NRC-93-4027 ATTACIBENT A APG00 RAI RESPONSES
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SUBMITTED DECEMBER 9,1993 RAI No.
Issue 460.015R0ll Sampling provisions 470.003R01:
X/Q values 720.158R01:
PRA-based seismic margins method 920.001 Vulnerability analysis 920.002 Listing ofsital equipment
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NRC REQUEST FOR ADDITIONAL INFORMATION
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0 Response R3 vision 1 Ouestion 460.15 Section 933. I1.5.3, and 11.5.4 of the SSAR provide incomplete information ca radiological sarnphng provisions for process and effluent streams. For example, the sampimg provisions for the waste monitor tank contents, the detergent waste morutor tant contents, the steam generator blowdown, and the condenser air removal system have not been identitied. Further, there is no reference to tritiurn measurements. Identify how the sample provisions for the liquid and gaseous process and effluent streams for the AP600 design meet the. sampling pronsions for such streams identified m Tables 1 arul 2 of Section 11.5 of the SkP.
Response
Tables 933-1. 93 3-2. 933-3,93.4-1 and 93.4-2 of the SS AR have been revised to include all peninent continuous and local samphng points for the AP600. To identify how the sample provisions for the liquid and gaseous process and ef fluent streams for the AP600 design meet the sampling specifications identified in Tables I and 2 of Section 11.5 of the SRP, the attached Tables 460.15tRI)-1 and 460.15(R1)-2 are provided. Tin.se tables list the hquid arxl gaseous process and effluent streams identified in the SRP ud provide reference to the pertinern AP600 SSAR table (s) from Sections 933 and 9.3.4 (plus penment cross references to related Table 11.5-1 ef Section 11.5 of the SSAR covenng radiation monitoring) for each specific stream. Where a stream is not appbcable to the AP600,it is so noted, Where streams are monitored, sampled or analyzed via provisions by downstream systems, this is also noted.
I SSAR Revision:
The revised SSAR tables from Sections 933 and 93.4 (933-1,933-2. 933-3,93.4-1 and 93 4-2) are attached for cross referencing with Tables 460.15(RI)-1 and 460.15(RI)-2 of this response.
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r NRC REQUEST FOR ADDITIONAL INFORMATION aa a::
Response Revision 1
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Table 460.15(RI)-1 (SRP Section 11.5)
Proviniens for Monitori.:g and Sampling Gaseous Strea ns Sample Provisions in Efiluent No.
Process System Grah Cont.
AP600 Response 4
5 6
1 Waste Gas lloidup System NG,113 g
Tables 9.3.3-2,1I.5-1 I
2 Cendenser Evacuation System N G,113 I
Tables 9.3.4-1,11.5-1 3
Vent & f, tack Release Pt. System 113 1
Table 11.5-1 4
Containment Purge Systems NG, I,113 I
Table 11.5-12 5
Auxiliary Building Ventilatmn Systen' N G,113 I
Table 11.5-12 6
Fuel Storage Area Ventilation Syster.
N G. 113 I
Table 11.5-12 7
Radwaste Area Ventilation System NG,113 I
Table 11.5-12 I
8 Turbine Gland Seal Cond. Vent System NG,113 I
Tables 9.3.4-1,11.5-1 I
9 Mechanical Vacuum Pump Exhaust (lfogging) System NG,113 i
Tables n.3.4-1,11.5-1 10 Evaporator Vent Systems NG.113 I
Not Applicable to AP600 3
11 Pre-Treatment 1.iquid Radwaste Tank Vent Gas Systems NG,113 I
Table 9.3.3-2 12 Flast' Tank and Steam Generator Dlowdown Vent Systems N G,113 i
Not Applicable to AP600 13 Turbine Building Vent Systems NG.113 I
Not Arrlicable to AP600 14 Pressurizer & Boron Recovery Vent Systems NG,113 i
Not Applicable to AP600 l
4GO ~ 5R1-2 W Westinghouse
NRC REQUEST FOR ADDITIONAL INFORMATION ii..iii Response Revision 1 e
1)
Via common vent for condenser evacuation, turbine gland acal cond. vent and mechanical vacuum pump exhaust systems (Nos. 2, 8,9).
2)
Also via vent and stack release pt. system.
3)
Via gaseous radwaste system.
4)
Nome gas radioactivity.
5)
Tntium.
6)
Iodine radioactivity, particulate radioactivity.
4GO.15R1-3 W Westingh00Se 4
t NRC REQUEST FOR ADDITIONAL INFORMATION
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Response Revision 1 t
Table 460.15(RI)-2 (SRP Section 11.5)
Pnwisions for Monitoring and Sampling Liquid Streams Sample Pnwisions in Efiluent No.
Process System Grab Cont.
AP600 Response 4
5 I
Liquid Radwaste (Batch) EfUuent System S&A,113 Table 9.3.3-2 2
Liquid Radwaste (Continuous) Effluent System S&A,113 S&A Tables 9.3J-2.11.5-1 3
Service Water System S&A, II)
S&A Tables 9 3.4-1, 9.3.4-2. 11.5-1 4
Component Cooling Water System S& A,113 S&A Tablen 9.3.3-2,11.5-1 5
Spent Fuel Pml Treatment System S&A,113 S&A Table 9.3.3-2 6
Equipment & iloor Drain Collection & Treatment System S&A,113 S&A Table 93.3-2I 7
Phase Separator Decant and lioldmg Basin Systems S&A, }{3 S&A Not applicable to AP600 8
Chemical & Regeneration Solution Waste Systems S&A,113 S&A Table 9.33-2I 9
Laboratory & Sample System Waste Systems S&A,113 S&A Table 9.3.3-2I 10 Laundry & Decontamination Waste Systems S& A,113 S&A Table 933-2I 11 Resin Sturty, Solidification & Daling Drain Systems S&A,113 S&A Table 93.3-2 12 Radwante Liquid Tanks (Outside the Buildings)
S&.A,113 S&A Not Applicable to APea 2
13 Storm and Underdrain Water System S&A,113 Not Applicable to AP600 I
14 Tanks and Sumps inside Reactor Buildmg S&A.113 S&A Tables 93.3-1,9.3.3-2,93.3-3 l
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4GO.15R1-4 W Westinghouse I
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NRC REQUEST FOR ADDITIONAL INFORMATION
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Response Revision 1 t
i Table 460.15(RI)-2 (SRP Cection 11.5)
Provisions for Monitoring and Sampling Liquid Streams Sample Provisions in Ef11uent No.
Process System Grab Cont.
AP600 Response 15 Boron Recovery System Liquid Efiluent S&A,113 S&A Not Applicable to AP600 16 Steam Generator Blowdown (Batch) Liquid Efiluent System S&A,113 S&A Not Applicable to AP600 17 Steam Generator Blowdown (Continuous) Liquid Efiluent S&A,113 S&A Tables 9.3.4-1, 9.3.4-2, 11.5-1 System 3
18 Secondary Coolant Treatment Waste & Turbine Building S&A,113 S&A Tables 9.3.4-1 and 9.3.4-2 Drain Systems 19 Ultrasonic Resin Cleanup Waste Systems S&A,113 S&A Not Applicable to AP600 20 Non-Contaminated Waste Water & PWR Turbine Building S&A,113 S&A Table 9.3.4-2 Clean Drain System 1)
Via hquid radwaate effluent system (see Nos. I and 2).
2)
No potentially radioactive process systems discharge into this system.
3)
Secondary coolant Treatment Waste N. A. Turbine drains are the same as clean drains (see No. 20).
4)
Samphng and analysis of radionuclides, to include gross radioactivity, identification and concentration of principal radionuclides and concentration of alpha emitters.
5)
Tntium i
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4GO.15R1-5 W Westinghouse l
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NRC REQUEST FOR ADDITIONAL INFORMATION
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Response Revision 1
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i Table 933-1 (Sheet I of 2)
Primary Sampling System Sample Points - Normal Plant Operations (Liquid and Gaseous)
Available l
Number of Type of Sample Point Name Points Sample
- Process Measurement Liquid Sample l
1.
RCS Hot leg (be-2 Grab Radioisotopic liquid, suspended solIdr., radioisotopic fore CVS gas, gross specific activity, hydrogen, I-131 demineralizer) conductivity, strontium, iron, tritium, pH, oxygen, l
chlorine, fluorine, boron, aluminum, silica, lithium radioisotopic liquid, lithium radioisotopic particulate, i
magnesium, sulfate, calcium, lithium 2.
Pressurizer Vapor 1
Grab Dissolved fission gases Space 3.
Pressurizer Liquid 1
Grab pH, oxygen, chlorine,11uorine, boron
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CVS Demineralizer 1
Grab Chlorine, fluorine, pH, radioisotopic liquid, radioisoto-j Downstream pic particulate, gross activity, conductivity i
5.
PXS Accumulator 2
Grab pH, chlorine, fluorine, boron 6.
PXS Core Makeup 2
Grab pH, chlorine, fluorine, boron Tank (at top) 7.
PXS Core Makeup 2
Grab pH, chlorine, fluorine, boron Tank (at bottom) 1 Grab Gross activity, gamma Occtrum, boron, chlorire and 8.
Containment Sump pH (pump discharge) 460.15R1-6 W Westinghouse
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NRC REQUEST FOR ADDITIONAL INFORMATION iiiE die
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Response Revision 1 Table 93.3-1 (Sheet 2 of 2)
Primary Sampling System Sample Points - Normal Plant Operations (Liquid and Gaseous)
Available Number of Type of Sample Point Name Points Sa mple*
Process Measurement Gaseous Sample 9.
Operating Deck 1
Grab Gamma spectnun, hydrogen, tritium Containment Air Source #1
- 10. Operating 1
Grab Gamma spectrum, hydrogen, tritium Deck Containment Air Source #2 nis column shows methods to obtain a sample for chemical analysis. It does not specify the fmquency of sampling nor does it specify actual h> cation of sample collection, " Grab" means that a grab sample is required for the intended chemical analysis. Depending on the sampling condition, this grab sample can be obtained in the laboratory or in the grab sampling unit. " Continuous" means that the mquired chemical analysis is performed via a probe that monitors the sampling stream continuously.
NRC REQUEST FOR ADDITIONAL INFORMATION jj"'
- =u Response Revision 1 Table 9.3.3-2 (Sheet 1 of 51 Local Sample Point Not in the Primary Sampling System (Normal Plant Operations)
Available Nu ml>er Type of Sample Point Name of Points Sample
- Process Measurement Liquid Sample 1.
CVS Boric Acid i
Grab pH, chlorine, fluonne, bomn, silica, suspended solids, Tank radioisotopic liquid, oxygen 2.
CVS Boric Acid 1
Grab Boron, chlorine, fluorine Batching Tank DWS 4
Gmb Ce xiu.:t ny, ;
c, r*ca, pH,.cr
- ; reluct elem:ner:di. ed c:a'., c grene i:npu- *, c:ygen, Scudne, ' emar
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grr ::peciOc ac:: ny, cdiun, :.ulf::
3.
CVS Letdown 1
Continuous Radiation monitor (See Section 11.5, Table 11.5-1) 4.
Residual Heat 2
Grab Radioisotopic liquid, suspended solids, radioisotopic Removal Heat Ex-gas, gross specific panyr activity, strontium, iron, changer tritium, hydrogen I-131, conductivity, pH, oxygen, chlorine, fluorine, boron, w4aee, aluminmn, silica, lithium radioisotopic liquid, lithium radioisotopic particulate, magnesium, sulfate, calcium, lithium 5.
PXS IRWST 1
Grab pH, oxygen, fluonne, boron, conductivity, gross specif-ic pavityr activity, sodium, sulfate, silica 6.
Continuous Radiation monitor (See Section 1 L5, Table 11.5-1)
(Outlet SGI) 7.
Continuous Radiation monitor (See Section 11.5, Table 11.5-1)
(Outlet SG2)
&FS inCue:Hafer 4
Cr~inuou:
Ce due:: ny, pH hea exchange-nd Scre ; de :ap W
P 460,15RI-8 W WestinEhouse P
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NRC REQUEST FOR ADDITIONAL INFORMATION m=
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Response Revision 1
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E Table 93.3-2 (Sheet 2 of 5)
Local Sample Point Not in the Primary Sampling System (Normal Plant Operations)
Available Number T pe of 3
Sample Point Name of Points Sample
- Process M 3asurement 8.
SFS Loops 2
Grab Conductivity, pH, chloride, silica, corrosion product (Upstream of SFS metals, gross activity, corrosion product activity, Pumps) fission product activity, iodine-131, tritium, turbidity, boron, corrosion product metals, organic impurides SFF dSM (afte-e Cc- ' nu =
Cc-de::,, pH
& nuper';
Gmh Ohi&, %,cc 2^: p r &,: net ', :: gen imtenties 9.
PCS Water Storage 1
Grab Hydrogen peroxide Tank W Lc b m:ed 4
C-*niem.ts Redi:.c- ',
'c (gr^ ^ rad! = t:r y)
....,..-.x
- 10. RC Drain Tank 1
Grab Gross radioactivity and identification and concentration of principal radionuclide and alpha emitters. Dissolved gases. State and federal environmental discharge requirement such as pH, suspended solids, oil and grease, iron, copper, scdium nitnte
- 11. WLS Degasifier 1
Grab Dissolved gases.
(downstream of degasifier discharge pump)
- 12. CCS Component 21 Grab pH, sodium, chloride, silica, corrosion prodnct metals, Cooling Surge corrosion inhibitors Tank feievweeam
" CCS p=p)
- 13. CCS Loops 2
Grab ph, sodium, chloride, silica, corrosion product metals.
(downstream of gross radioactivity and identification and concentration CCS pumps) of principal radionuclide and alpha emitters i
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NRC REQUEST FOR ADDITIONAL INFORMATION Response Revision 1 Table 9.3.3-2 (Sheet 3 of 5)
Local Sample Point Not in the Primary Sampling System (Normal Plant Operations)
Available Number Type of Sample Point Name of Points Sample
- Process Measurement
- 14. CCS Hot Leg 1
Continuous Radiation monitor (See Section 11.5 Table 11.5-1)
(upstream of CCS pumps)
- 15. WLS Discharge 2
Continuous Radiation monitor (See Section 11.5, Table 11.5-1)
- 16. WLS Eftluent 1
Grab Gross radioactivity and identification and concentration Holdup Tank of principal radionuclide and alpha ermniters MT05A
- 17. WLS Effluent 1
Grab Gross radioactivity ard identification and concentration Holdup Tank of principalindionuclide and alpha emmiters MT05B
- 18. WLS Waste 1
Grab Gross radioactivity arxl identification and concentration Holdup Tank of principal radionuclide and alpha emmiters MT06A
- 19. WLS Waste 1
Grab Gross radioactivity and identification and concentration Holdup Tank of principal radionuclide and alpha emmiters MT06B
- 20. WLS EfDuent 1
Grab Gross radioactivity and identification and concentration Monitor Tank of principal radionuclide and alpha emitters. State and MT07A federal environmental discharge requirement such as pH, suspended solids, oil and grease, iron, copper, sodium nitrite
- 21. WLS EfDuent 1
Grab Gross radioactivity and identification and concentration Monitor Tank of principal radionuclide and alpha emitters. State ard MT07B federal environmental discharge requirement such as pH, suspended solids, oil ard grease, iron, copper, sodium nitrile 460.15R1-10 W Westinghouse
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NRC REQUEST FOR ADDITIONAL INFORMATION Eb i
Response Revision 1 E
i Table 9.3.3-2 (Sheet 4 of 5)
Local Sample Point Not in the Primary Sampling System (Normal Plant OperationO Available Number Type of Sample Point Name of Points Sample
- Process Measurement
- 22. WLS Waste 1
Grab Gross radioactivity and identification and concentration Moi. >r Tank of principal radionuclide and alpha emitters. State and MTiA federal environmental discharge requirement such as pH, suspended solids, oil and grease, ironi copper, sodium nitrite
- 23. Wd Waste 1
Grab Gross radioactivity and identification and concentration Monitor Tank of principal radionuclide and alpha emitters.. State and M T 08It federal emironmental discharge requirement such as pH, suspended solids, oil and grease, iron, copper, sodium nitrite
- 24. WLS Detergent 1
Grab Gross radioactivity and identification and concentration i
Waste Tank of principal radionuclide and alpha emitters
- 25. WLS Detergent 1
Grab Gross radioactivity and identification and concentration f
Waste Monitor of principal radionuclide and alpha emitters. State and Tank federal emironmental discharge requirement such as plI, suspended solids, oil'and grease, iron,' copper, sodium nitrite
- 26. WLS Chemical 1
Grab Gross radioactivity and identification and concentration Wasir %k of principal radionuclide and alpha emitters
- 27. WSS Spent Resin 1
Grab Gross radioactivity, radionuclide concentrations Gaseous Sample
- 28. Reactor Coolant 1
Grab
Drain Tank (overpressure ges f
space)
NRC REQUEST FOR ADDITIONAL INFORMATION
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Response Revision 1 Table 9.3.3-2 (Sheet 5 of 5)
Local Sample Point Not in the Primary Sampling System (Normal Plant Operations)
Available Number Type of Sample Point Name of Points Sample
- Process Measurement
- 29. VES MCR 2
Grab Air quality, oxygen, carbon monoxide, carbon dioxide, Emergency Air contaminants Supply IIcaders
- 30. WGS Effluent 1
Continuous Radiation monitor fm aHe pr :W:, paia =,
Discharge to Envi-
+ntem (See Section i1.5. Table 11.5-1) ronment
- 31. WGS Inlet 2
Continuous Oxygen, moisture
- 32. WGS Inlet 1
Grab Noble gases, imhne, paniculates, tritium
- 33. WGS Guard Bed 1
Grab Moisture, noble gases, iodine, paniculates, tritium Outlet
- 34. WGS Delay Bed 1
Grab Moisture, noble gases, iodine, particulates, tritium Outlet MV02A
- 35. WGS Delay Bed I
Grab Moisture, noble gases, iodine, particulates, tritium Outlet MV02B This column shows methods to obtain a sample for chemical analysis. It does not specify the frequency of sampling nor does it specify actual location of sample collection, Grab" means that a grab sample is required for the intended chemical analysis. Depending on the sampling condition, this grab sample can be obtained in the laboratory or in the grab sampling unit. " Continuous" means that tie required chemical analysis is perfomied via a probe that monitors the sampling stream continuously.
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460.15R1-12 W Westinchouse o
NRC REQUEST FOR ADDITIONAL INFORMATION I:@
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Response Revision 1 Table 933-3 Primary Sampling System Sample Points - Post-Accident Operations (Liquid and Gaseous) pw?]
Sample Point Name Available Type of Process Measurement Number of Sample
- Points Liquid Sample:
RCS hot leg 2
Grab Gross activity, gamma spectrum, boron, dissolved (before CVS chlonne, hydrogen and oxygen and pH demineralizer)
Containment 1
Grab Gross activity, gamma spectrum, boron, dissolved sump (pump hydrogen chloride and oxygen, and pH discharge)
P=u-ire Epsid Grieb
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W Gaseous Sample:
Containment WH"t"wed-Gamma spectrum analysis Atmosphere This column shows methods to obtain a sample for chemical analysis. It does not specify tie frequency of sampling nor does it specify actual location of sample collection, " Grab" means that a grab sample is required for the intended chendcal analysis. Depending on the sampling corxhtion, this grab sample can be obtained in the laboratory or in the grab sampling unit. " Continuous" means that the required chemical analysis is performed via a probe that monitors the sampling stream continuously.
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NRC REQUEST FOR ADDITIONAL INFCRMATION Response Revision 1 TaNe 9.3.4-1 (Sheet I of 2)
Secondary Sampling System (Continuous Measurements)
Continuous Sample Points Process Measure.nents 1.
Ilotwell(Condenser Shell A)
Cation Corxluctivity Sodium 2.
Hotwell (Condenser Shell B)
Cation Conductivity Sodium 3.
Specific Conductivity Cation Conductivity Sodium Dissolved Oxygen pH Oxygen Scavenger Residual 4.
Steam Generator Blowdown +6G-A)(SGI).
Specific Conductivity Cation Conductivity j
]
pH Sulfate Radiation Monito/"
5.
Steam Generator Blowdown A (SG2).
Specific Condoaivity Cation Conductivity Sodium pli i
Sulfate Radiation Monito/"
6.
Condensate Pump Discharge Specific Conductisity Cation Conductivity Sodium Dissolved Oxygen i
pli 460.15R1-14 W Westinghouse
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NRC REQUEST FOR ADDITIONAL INFORMATION I
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Response Revision 1 5
Table 9.3.4-1 (Sheet 2 of 2)
Secondary Sampling System (Continuous Measurements) 7.
Condensate Polisher Outlet Specific Conductisity Cation Conductivity Sodium 8.
Deaerator inlet Specific Conductisity Cation Conductivity Sodium pH Gulfate Dissolved Oxygen 9.
Main Steam System (SG-A)(SGI)
Cation Conductivity 10.
Main Steam System (SG-B)(SG2)
Cation Conductivity 11.
Demineralized Water Treatment Specific Conductisity l
System Effluent 12.
Demineralized P-:g T=k
.. Dissolved Oxygen Water Treatment System Degasifier Effluent 13.
Service Water Cooling..
Radiation Monitot*
Tower Blowdown i
Radiation Monito/"
- 14. Turbine Island Vents,.
Drains & Relief System j
Reference Section 11.5, Table 11.51 for details.
l 460.1SR1-15
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NRC REQUEST FOR ADDmONAL INFORMATION Ta Response Revision 1 Table 9.3.4-2 (Sheet 1 of 2)
Secondary Sampling System (Process Grab Sample Points) 1.
Hotwell Shell A 2.
Hotwell Shell B 3.
Condenser Tubesheets 4.
Feedwater 5.
Steam Generator Blowdown (SG-A)(SGI) 6.
Steam Generator Blowdown 46G-B)(SG2) 7.
Condensate Pump Discharge 8.
Condensate Polisher Outlet 9.
Deaerator Inlet 10.
Deaerator Outlet 11.
Main Steam System (SG-A3 (SGI) 12.
Main Steam System (SG.-B)(SG2) 13.
Low Pressure Heater Drains (IA & IB) 4?
=:r Oude' g; 97 w.... 3;;9.p..;335;g c 73c-ng ur%. sp.. n; : 5;g;ge.,.a w,3 9; 3; 14 Moisture Separator Reheater Drain Tank Outlet 15.
Demineralized Water Treatment System Effluent 16.
Demineralized Water Treatment System Degasifier Effluent
^-v n; ":.;r Basia 17 C~aing Tr e.e-B!: ca -
17.
Demineralized Water Storage Tank 18.
Demineralized Water Storage Tank Degasifier Effluent 19.
Condensate Storage Tank 20.
Auxiliary Boiler Feedwater end Pr--
21.
Auxiliary Boiler Steam
- 22. Turbine Building Closed Loop Cooling System
- 23. Hot Water Heating System 24 Main Condenser Circulating Water
- 25. Circulating Water Cooling Tower Basin
- 26. Circulating Water Cooling Tower Blowdown
- 27. Service Water Cooling Tower Basin
- 28. Senice Water Cooling Tower Blowdown 29, Service Water Heat Exchanger A Inlet
- 30. Service Water Heat Exchanger A Outlet
- 31. Senice Water Heat Exchanger B Inlet
- 32. Service Water Heat Exchanger B Outlet 460.15RI-16 W WestinEhouse 1
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NRC REQUEST FOR ADDITIONAL INFORMATION pf
=m Response Revision 1 Table 9.3.4-2 (Sheet 2 of 2)
Seeandary Sampling System (Process Grab Sample Points)
- 33. Turbine Stator Cooling 34 Turbine Building Drain Tanks
- 35. Waste Water Retentior Basin
- 36. Steam Generator Blowdown Effluent 1
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NRC REQUEST FOR ADDITIONAL INFORMATION Response Revision 1 Joestion 470.3 For each of the postulated accidents, proside the X/Q values from the release point to the location u here the release is drawn into the control room envelope. Values should be for the following time periods: 0-2 hours,0-8 hours, 8-24 hours,14 days and 4-26 days (Section 23.4L
Response
A calculation has been performed to determine the appropriate atmospheric dispersion factors (X/Qs) used to determine the radioactive material entering the control room envelope from outside air Ic kage and frca MCR/TSC HVAC operation. The following accidents, in addition to the LOCA currently presented i 1 the SSAR, are considered in determining contml room operator doses to address the postulated accidents which c( uld affect the control room dose:
15.1.5 Main Steam Line Break 1533 Reactor Coolant Pump Shaft Seizure (Locked Rotor) 15.4.8 Rod Ejection Accident 15.6.2 Small Line Break 1563 Steam Generator Tube Rupture The potential release points associated with the above accident cases are:
Steam vents on the auxiliary building roof Steam lire safety valves /PORY exhaust from auxiliary building roof Condenser air removal exhaust to the turbine building vent Fuel handhng area release assuming HVAC systern is inoperable Wind from only sectors encompassing these points have an impact on control room habitability.
The MCR has two potential sources of intake or infiltration: the control room air intake on the auxiliary building roof at elevation 160' 6" and infiltration through the doors into the MCR at elevation 117' 6".
The X/Qs for MCR habitability assessment are determined by:
Using the methodology in NUREG/CR-5055 to determine the hourly average X/Qs for various wind speeds and stability classes Using meteorological data from three different sites, the mnual average MCR X/Q is determined Determining the fifth percentile MCR X/Qs from the same meterorological data Obtaining time-averaged X/Qs for other than 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> using logarithmic appmximation discussed a
470.3(R1)-1 i
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i NRC REQUEST FOR ADDITIONAL INFORMATION En: :EE
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Response Revision 1 The resultant X/Q values for each of the four release points and both intake / infiltration points are presented below:
Steam Steam Line Condenser Fuel Vents Safety Valves Air Removal Handling Area Control Room IIVAC Intake 0-2 hours 3.94e-03 3.72e-03 1.66e-03 1.81e-04 l
0-8 hours 3.03e-03 2.98e-03 9.20e-(4 1.23e-(u 8-24 hours 2.66e-03 2ife-03 6.86e-04 1.02e-N
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1-4 days 2.00e-03 2.09e-03 3 62e-N 6.73e-05 4-30 days 133e-03
.1.48e-03 1.45e-(M 3.71e-05 Annual Average 8.03e-04 9.68e-04 4.72e-05 1.79e-05 Control Room Door l
0-2 hours 3.27e-04 6.29e-N 1.51e-03 135e-N 0-8 hours 2.38e-N 4.13e-N 9.93e-N 8.76e-05 P
8-24 hours 2.04e-04 3.35e-N 8.06e-04 7.06e-05 1-4 days 1.44e-04 2.12e-04 5.15e-N 4.43e-05 4-30 days 8.81e-05 1.10e-04 2.72e-04 2.27e-05 Annual Average 4.82e-05 4.95e-05 1.26e-N 1.00e-05 SSAR Revision: NONE 470.3(RI)-2 W Westinghouse
NRC REQUEST FOR ADDITIONAL INFORMATION Response Revision 1 Ouestion 720.158 Provide a detailed description of the methodology used in performing the PRA-ba. sed seismic m ugins analysis. This description is particularly importaru because them are hnuted examples of the practical implementauon of this methodology.
Response
Attachment I to this RAI response prosides the methodology f or peiforming the AP600 risk-based seismic margins analysis.
PRA Revision: NONE 720.158(RI)-1 W Westinghouse j
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Response Revision 1 ATTACHMENT 1 to RAI 720.158(RI)
METHODOLOGY FOR PERFOR311NG THE AP600 RISK-BASED SEISMIC 51ARGINS ANALYSIS
1.0 INTRODUCTION
In accordance with Section II.N, Site-Specific Probabilistic Risk Assessments and Analysis of External Events, of SECY-93-087 (Reference 1), the Nuclear Regulatory Commission approved the following staff recommendation:
"PRA insights will be used to suppon a margins-type assessment of seismic events. A PRA-based seismic margins analysis will consider sequence-level High Confidence, Low Probability of Failures (HCLPFs) and fragilities for all sequences leading to core damage or containment failures up to approximately one and two-thirds the ground motion acceleration of the Design Basis SSE."
The seismic margins analysis presented in AP600 Probabilistic Risk Assessment (PR A) Appendix H.3 and request for additional infonnation (RAI) response 720.15 was performed prior to the issuance of the SECY report. The Appendix H.3 seismic margins analysis is based on a cutset-level rather than on a sequence-level evaluation.
The most efficient and complete way to answer RAls 720.158, 720.159, 720.162 and 720.166 is to perform additional seismic margins analysis that supports and supplemems the present analysis.
The risk based seismic margins analysis rnethodology discussed herein and the analysis to be performed in accordance with this methodology satisfies the intent of SECY-93-087 and answers the NRC RAls.
Table 1.0-1 provides brief definitions of PRA terminology.
Since the AP600 nonsafety-related components are not seismic category I, it is conservatively assumed for the risk-based seismic margins analysis that no credit is taken for the mitigation functions of the nonsafety-related components and systems. A PR A sensitivity analysis has been performed that does not credit the mitigation functions of the nonsafety-related systems. The analysis is referred to as the focused PRA (Reference 2) and was submitted to the NRC as a part of resolving the Regulatory Treatment of Nonsafety Systems (RTNSS) issue for the AP600. The focused PRA is based on the AP6(0 baseline PRA analysis (Reference 3). The focused PRA event tree and fault tree models are modified as necessary for the seismic margins analysis. Note the mission time for the baseline and focused PRAs and thus for the seismic margins analysis is 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> from the time an accident occurs.
720.158(R1)-2 3 Westinghouse
NRC REQUEST FOR ADDITIONAL INFORMATION
@ isi Response Revision 1 The safety-related systems and functions which are included in the focused PRA evaluation, and thus in the risk-based seismic margins analysis, are listed in Table 1.0-2.
For this risk-based seismic margins analysis, HCLPFs are calculated and reported for systems at the sequence level. This is accomplished by calculating HCLPFs for each seismic event tree top event that represents a safety-related system or function. Once HCLPFs for the necessary systems are calculated, HCLPF values are calculated for each event tree core damage sequence. In addition, insights related to random and/or human failures are reported, as deemed appropriate for each sequence.
I I
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Response Revision 1 TABLE 1.0-1 (Sheet 1 of 2)
DEFINITION OF PRA TERMINOLOGY RTNSS Regulatory Treatment of Nonsafety Systems. The AP600 user passive safety systems that rely on natural forces such as density differences and gravity to provide water for core and containment cooling. These passive safety systems do not include active equipment such as pmnps. The AP600 active systems are designated as nonsafety-related systems cycept for limited portions of the systems that provide safety-related isolation functions, such as containment isolation.
Credit is not taken for these active systems in the Chapter 15 licensing design basis accident analyses unless their operation makes the consequences of an accident more limiting. The nonsafety-related systems in the AP600 supplement the capability of the safety-related passive systems. The NRC and industry have defm' ed a process to evaluate the importance of the nonsafety-related systems and for maintaining appropriate regulatory oversight referred to as RTNSS.
Baseline PRA The baseline PRA credits mitigation ftmetions for those safety-related and nonsafety-related systems and components modeled in the PRA. The PRA evaluation, which is documented in the AP600 PRA report (Reference 3), was submitted to the NRC in June 1992.
Focused PRA The focused PRA credits udtigation functions for only those safety-related systems and components modeled in the baseline PRA. The focused PRA was submitted to the NRC in September 1993.
Initiating event A failure caused by the seismic event that induces a reactor trip.
Event tree Inductive logic models for identifying the possible outcomes of a given initiating event. An event tree is developed for each type of initiating event. The e>ent tree models the subsequent events (called top events) that are required to mitigate the accident.
Top event System or function success / failure criteria for the mitigation of an accident, as defined by the event tree.
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TABLE 1.0-1 (Sheet 2 of 2)
DEFINITION OF PRA TERMINOLOGY Fault tree A logic model that represents the possible ways a system or function may fail based upon the failure criteria defined by the event tree top event. The logie model indicates how the combination of failure of a component or other events such as operator errors cause the system to fail.
Basic event The equipment faults or other faults (such as operator errors) modeled in the fault tree. No further development of the fault is evaluated from this point.
Cutset Combination of basic event failures that cause the top event to occur.
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NRC REQUEST FOR ADDITIONAL INFORMATION El Response Revision 1 TABLE 1.0-2 SAFETY-RELATED SYSTEMS AND FUNCTIONS CREDITED IN THE RISK-BASED SElSMIC MARGINS ANALYSIS i
Passive core cooling
- In-containment refueling water storage tank injection and contaimnent recirculation
- Core makeup tank
- Passive residual heat removal (PRIIR)
- Automatic depressurization Containment systems
- Passive containment cooling
- Contaimuent isolation Class IE de and uninterruptible power supply (UPS) power Protection and safety monitoring
- Engineered safeguards actuation
- Safety-related monitoring Reactor coolant pump trip Steam generator isolation r
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Response Revision 1 2.0 METIIODOLOGY Steps involved in performing a risk-based seismic margins analysis include: seistnic initiating event evaluation, seismic event tree development, systems analysis, accident sequence quantification, and containment isolation capabilities. Evaluation of the seismic initiating events and development of the seismic event trees is discussed in Section 2.1. IICLPFs are calculated for the seismic category I safety-related systems which are called upon via the seismic event trees to mitigate an accident caused by the initiating seismic event. The systems evaluation is discussed in Sectica 2.2. The core damage sequences defined by the seismic event trees are " quantified." The event trees are not quantified to generate core damage sequence frequencies, but rather the result of the quantification is a list of core damage sequences with the 11CLPF for each sequence and, where appropriate, the random and human error failure probabilities for the sequence. The quantification process is discussed in Section 23. The final step of the risk-based seismic margins analysis is to perform a seismic containment performance analysis. The process is discussed in Secuan 2A.
2.1 SEISMIC INITIATING EVENT AND EVENT TREE ANALYSIS The first step to performing a seismic analysis is to evaluate which initiating events could occur as a result of a seismic event. The risk-based seismic margins analysis does not consider seismic hazard curves; therefore, initiating event frequencies are not calculated for each seismically-generated initiating event category. Ahhough seismically-generated initiating event frequencies are not calculated, it is important to evaluate the scismic vulnerability of the components and systems that contribute to the initiating event categories. This is done by estimating a llCLPF for each seismic initiating event category. The categories, which are based on the RTNSS focused PRA initiating events, include:
General transient (includes loss of offsite power)
+
less of coolant accidents (LOCAs)
+
Steam generator tube rupture (SGTR)
+
Steam line breaks less of feedwater without scram (ATWS)(seismically-induced failure to scram).
+
In the RTNSS focused PRA, seven of the baseline PRA transient initiating events are grouped with the loss of offsite power event creating a " general transient" categog. These seven events include: turbine or reactor trip, loss of feedwater to steam generator, secondag to primary side power mismatch, spurious "S" signal, loss of component cooling water system. loss of service water system, and loss of compressed air system. For the seismic margins andysis, the general transient event is essentially a loss of offsite power event, i
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It is not necessary to estimate a HCLPF for the general transient initiating event, since offsite ac power is a nonsafety-related system for AP600. Mitigation of the general transient initiating event is evaluated in the risk-based seismic margins analysis.
e A HCLPF is es*imated for the remaining four initiating event categories. If the seismic initiating event HCLPF is projected to be less than 0.5g. which represents one and two-thirds the ground motion acceleration of the AP600 design basis SSE, then the initiating event is funher evaluated in the risk-based seismic margins analysis. If the seismic initiating event HCLPF is greater than 0.5g, then no further seismic margins evaluation is required for that event.
Once the seismic initiating events with a HCLPF of less than 0.5g are determined, a seismic event tree is developed. 'The event trees used in the AP600 focused PRA provide the starting point for developing the necessary seismic event trees.
i An example of a loss of offsite power event tree is shown in Figure 2.1-1. The top events on the event f
tree represent the safety-related systems that are required to operate in order to mitigate the accident from progressing to a core damage event. Since ac power is nonsafety-related, the probability of recovering the grid within I hour or within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />, as questioned in the event tree, is set to 1.0, meaning offsite power is unavailable following the seismic event. The example loss of offsite pwer event tree can be redrawn as shown in Figure 2.1-2.
In order to evalnate the focused PRA event trees for the risk-based seismic margins analysis, a HCLPF and, as appropriate, a random failure or human error probability is assigned to each event tree top event.
De seismic event trees are created by assigning a HCLPF and random failure or human error probability to each top event.
The methodology for assigning HCLPFs and failure probabilities for each event tree top event is discussed in Section 2.2.
j 2.2 SYSTEM SEISMIC ANALYSIS In order to quantify the seismic event trees, each event tree top event is assigned a HCLPF value. In addition, random failures and human error events whose probabilitics are greater than or equal to IE-3 i
are recorded for each top event. The probability cutoff of IE-3 is based on the NRC request in RAI 720.159, pan b. This section discusses the calculation process used to define the system or top event HCLPF value. An example is provided.
For each top event, a HCLPF value is estimated. For example, the top event would be the failure of a safety-related system which is requested to operate to help mitigate an accident caused by a scismic event.
The component and stmetural failures of the system and its supports are considered. The components to 720.158(RI)-8 W Westinghouse
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i Response Revision 1 t
i be evaluated could include: pipes, valves, tanks, heat exchangers, and any support system components such as instrumentation and control equipment. The buildings containing the equipment are also included.
A conservative assumption to be used in the PRA-based seismic evaluation for creating the seismic fault trees is that if one component fails due to the seismic event, then all components of that same type for l
that system fail as well; thus creating a common cause failure event. For example,if a system contains two parallel motor-operated valves, and one fails due to the seismic event, it is assumed that the second valve fails as well. His assumption is conservative because the components may experience different excitation due to their location, orientation or support condition.
A seismic fault tree for each event tree top event is created. Included in the fault tree are the structural and component seismic failures that could cause the system to fail. A HCLPF value is assigned for each of the fault tree basic events that represent components and structures. HCLPF values are reported in Table H-1 of the AP600 PRA report for components and structures.
The seismic fault tree is " quantified" using the min-max approach to determine the system HCLPF. The min-max approach is defined as follows:
For events tmder an AND gate, all basic events must occur in order to progress up a level in the fault tree. Thus, the highest HCLPF value for the events under an AND gate represents the cutset or top event HCLPF.
For events under an OR gate, any one of the basic events occurring cause progression up the fault tree. Thus, the lowest HCLPF value represents the top event HCLPF.
Figure 2.2-1 represents a seismic fault tree. The HCLPF values for each fault tree besic event are recorded under the event (event X has a HCLPF of 0.62g, event Y has a HCLPF of 0.91g). The HCLPF value that represents the event "A and B and C occurs" is calculated as follows:
HCLPF for event A 0.53g HCLPF for event B 0.62g HCLPF for event C 0.91g Since these three events are connected under an AND gate, the maximum (highest) HCLPF value for the events is selected to represent the HCLPF for event "A and B and C occurs." Thus, the HCLPF for this event is 0.91g. Now the HCLPF for system Q is calculated as follows:
W Westinghouse 720.158(RI)-9 I
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Response Revision 1 HCLPF for event X 0.62g HCLPF for event Y 0.91g HCLPF for event Z 0.86g HCLPF for event A&B&C 0.91g These four events are combined under an OR gate. Using the min-max approach, the minimum (lowest)
HCLPF value under the OR gate is selected. Thus, the HCLPF for top event " System Q" is 0.62g.
To further illustrate the system seismic analysis, the loss of offsite power example discussed in Section 2.1 is continued here.
As shown in Figure 2.!-2, there are seven top events:
No battery common cause Passive RHR (PRHR)
+
Core makeup tank
+
Automatic depressurization Accumulators Injection Recirculation A HCLPF is calculated for each top event. In order to calculate the HCLPF, a seismic fault tree is developed for each top event. The seismic fault tree illustrates the ways the system may seismically fail.
For example, ihe passive RHR may seismically fail due to failure of any of the following structures or components:
PRHR heat exchangers PRRR valves P231R piping
+
Containment building interior structures (structure housing the PRHR system)
Support system failures (de power to open valves) l Since any one of these structure or component groups failing cause system failure, the events are combined under an OR gate. Figure 2.2-2 illustrates the passive RHR seismic fault tree. Based on the llCLPF values for components and structures presented in AP600 PRA Table H-1, a HCLPF value is assigned to each fault tree basic event. The HCLPF values are shown on the fault tree under each event.
The fault tree is then quantified using the min-max approach.
Since all events in the fault tree are under an OR gate, the minimum HCLPF value represents the passive RHR system HCLPF. Thus, the passive RHR system HCLPF is evaluated to be 0.5g.
720.158(RI)-10 3 Westinghouse
4 NRC REQUEST FOR ADDITIONAL INFORMATION y
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~
The second item that is evaluated for tre passive RHR top event is whether any random failures or human errors with a cutset probabihty of IE-3 or greater exist for the system. This is determined by examining the passive R!TR system dominant cutsets from the focused PRA. Any cutset whose probability is greater than 1E-3 is recorded. The cutset may represent only random failures, only human errors, or a combination of both random and human failures.
According to the example loss of offsite power event tree shown in Figure 2.1-2, two passive RHR fault trees are called upon: RHR1 and PHR2. The cutset files for both of these trees is reviewed to determir.e if any cutsets exist whose probability is greater than IE-3. In neither case was a cutset found to be greater than IE-3. Thus there are no random or human faihues to report for the passive RHR top event in the example loss of offsite power seismic event tree.
Once a HCLPF value is determined for each seismic event uce top event, the event trees are qurmtified as discussed in Section 2.3.
2.3 SEISMIC EVENT CORE DAMAGE SEQUENCE EVALUATION Ore the
'ie*'" < '- - reated and a !!CLPF is estaad for cach a cui imee iop event, die crem uee core damage sequences can be evaluated.
The seismic event tree is quantified using the min-max approach that was discussed in Section 2.2. Each event tree sequence leading to a core damag end state is evaluated.
An example of a transient seismic crent tree with fictitious top event HCLPFs is presented in Figure 2.3-1.
The quantification of the seismic event sequences leading to a core damage end state is presented in Table 2.3-1, 2.4 CONTAINMENT PERFORMANCE SEISMIC EVALUATION The next step in the risk-based seismic margins analysis is to proceed to the containment evaluation by generating a list of seismic event sequences leading to containment failure.
The Level 2 focused PRA containment event trees (CET) are the starting point for developing the seismic CETs. The prceen steps for evaluating the Level 2 PRA CETs are essentially the same as described in Sections 2.1 through 2.3 for the seismic core damage sequences. First, the focused PRA CETs are modified as necessery to create seismic CETs. Second, the systems and functions representing the seismic CET top events are evaluated by calculating a HCLPF for each top event. This is done in tiie same manner as described in Section 2.2. The third ste; is to quantify the seismic CETs. Before the seismic CETs can be quamified, the entry HCLPF from me core damage sequences leading into the seismic CET must be detemnined. Note that the core damage end states (I A.1B, etc.) define which containment event 720.158(RI)-11 3 Westinghouse
NRC REQUEST FOR ADDITIONAL INFORMATION
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=E Response Revision I tree to proceed to. The minimum sequence llCLPF from the core damage evaluation that leads to the specific CET is conservatively used. For example, suppose three core damage seismic sequences lead to core damage end state 1 A, and the three sequence llCLPFs are:
Seismic Event Tree Sequence No.
0.62g Steam generator tube rupture 2
0.86g Loss of offsite power 35 0.59g The HCLPF chosen to represent the entry into the 1 A seismic CET is 0.59g. Any one of these three sequences lead to end state 1 A, which is representative of an OR gate. Using the min-max approach, the minimum IICLPF value is chosen because of the "OR gate" This is a conservative approach to evaluating the seismic CET and is used for the AP600 risk-based seismic margins analysis in order to simplify the evaluation.
Once the seismic CET top event HCLPFs and the entry llCLPF into the seismic CET are determined, the last step of the containment perfc=ance scismic cvaluation is pe: formed. The sci:mic CET quantification follows the same process as described in Section 2.3 for the core damage seismic evaluation.
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NRC REQUEST FOR ADDITIONAL INFORMATION Response Revision 1
^
TABLE 2.3-1 EXAhiPLE SElan11C ACCIDENT SEQUENCE QUANTIFICATION OF EVENT TREE SilOWN IN FIGURE 2.3-1 Sequence No.
Accident Sequence Ouantification Sequence HCLPF 3
RH
- R = 0.70g
- 0.76g 0.76g 4
RH
- 1 = 0.70g * (0.76g + 5E-3) 0.76g + (0.70g
- 5E-3) 5 RH
- AD =
0.70g
- 0.68g 0.70g 7
RH
- Chi
- R = 0.70g
- 0.52g
- 0.76g 0.76g 8
RH
- Ch1
- I = 0.70g
- 0.52g * (0.76g + 5E-3) 0.76g + (0.70g
- SE-3) 9 RH
- Chi
- AC = 0.70g
- 0.52g
- 0.75g 0.75g 10 RH
- CA1
- AD = 0.70g
- 0.52g
- O.0Sg 0.70g 12 B
- RH = 0.62g
- 0.70g 0.70g i
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l NRC REQUEST FOR ADDITIONAL INFORMATION
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Response Revision 1
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Figure 2.1-1 Example Loss of Offsite Power Event Tree 720.158(RI)-14 W WB5 tin house i
6 t4RC REQUEST FOR ADDITIONAL INFORMATIOtt
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3E n CVT ADS 10 10 11 CA FATT rma2 1p Sc Figure 2.1-2 Example Loss of Offsite Power Seismic Event Tree W Westinghouse 720.158(R1)-15
NRC DEQUEST FOR ADDmONAL INFORMATION
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Figure 2.2-1 Example Seismic Fault Tree I
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Response Revision 1 5
- 1.
pa-n
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NRC REQUEST FOR ADDITIONAL INFORMATION Response Revision 1
- tCL8'F O. t.> 2 g C ' &,
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,e Figure 2.3-1 Example Seismic Event Tree 720.158(RI)-18 W WestinEhouse
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3.0 CONCLUSION
The risk-based seismic margins analysis methodology presented in this RAI response is specifically for use on AP600. The methodology meets the PRA-based seismic margins requirement as specified in SECY-93-087 and addresses the NRC seismic margins questions posed in several RAls.
The result of the risk-based seismic margins analysis will be a listing of the seismic sequences leading to a core damage end state for each seismic event tree. The results provide a list of the seismic sequences leading to a containment failure (release category) end state for the seismic containment event tree.
4.0 REFERENCES
1.
SECY-93-087. Policv, Technical and Licensine issues Pertainine to Evolutionary and Advanced Licht-Water Reactor (ALWR) Desiens, July 1993.
1 2.
Attachment to "AP600 Implementation Report for Regulatory Treatment of Nonsafety-Related Systems (WCAP-13856)," Westinghouse letter number ET-NRC-93-3974/NSRA-APSL-93-0356, datcd Sq,1cuil.cI 24,1993.
3.
AP600 Probabilistic Risk Assessment, Westinghouse Electric Corporation and ENEL, DE-AC03-90SFIS495, June 26.1992.
i l
)
720.158(RI)-19 3 Westinghouse
i l
NRC REQUEST FOR ADDITIONAL INFORMATION Question 920.1 Section 5.2.2.1 of Chapter 9 of the EPRI Advanced Light Water Reactor (ALWR) Utility Requirements Document (URD) for passive plant designs states that a vulnerability analysis should be performed prior to finalizing the design to analyze issues associated with insider and outsider sabotage. In Section 5.2.2 of the EPRI final Safety Evaluation Report, dated August 31, 1993, the staff stated that a vulnerability analysis would be reviewed as part of an individual application. Westinghouse has stated that it will comply with the EPRI ALWR URD. Provide that analysis.
Response
The vulnerability analysis, which considers both the ins: der and outsider sabotage threat, is the responsibility of the Combined License applicant.
SSAR Revisions: NONE l
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Question 920.2 Section 13.6.5.2 of the AP600 SSAR states that a listing of vital equipment is provided in the APo00 Security Design Report. The Security Design Report, dated June 30,1992, did not contain a list of vital equipment. Provide a listing of vital equipment for the AP600 design.
Response
Table 2 of the AP600 Security Design Repon provides a general listmg of vital systems and equipment and the associated plant areas where they are located. These areas must be included within protected areas to restrict access to these systems and equipment. A list of vital equipment will be provided by February 1994.
SSAR Revision: NONE PRA R6 vision: NONE 92a2-i W westingnouse