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{{#Wiki_filter:1 PrairieIslandNPEm Resource From: Vincent, Robert [Robert.V incent@xenuclear.com]
{{#Wiki_filter:PrairieIslandNPEm Resource From:                     Vincent, Robert [Robert.Vincent@xenuclear.com]
Sent: Thursday, December 11, 2008 2:48 PM To: Nathan Goodman; Richard Plasse; Stuart Sheldon Cc: Eckholt, Gene F.; Davis, Marlys E.
Sent:                     Thursday, December 11, 2008 2:48 PM To:                       Nathan Goodman; Richard Plasse; Stuart Sheldon Cc:                       Eckholt, Gene F.; Davis, Marlys E.


==Subject:==
==Subject:==
Four PINGP License Renewal RAI Response Letters Attachments:
Four PINGP License Renewal RAI Response Letters Attachments:               20081211 Response to NRC RAI Letter dtd 11-19-08.pdf; 20081211 Response to NRC RAI Letter dtd 11-20-08.pdf; 20081211 Response to NRC RAI Letter dtd 11-25-08.pdf; 20081211 Response to NRC RAI Letter dtd 12-1-08.pdf Attached are four RAI response letters that were signed out today. Let me know if you have any questions.
20081211 Response to NRC RAI Letter dtd 11-19-08.pdf; 20081211 Response to NRC RAI Letter dtd 11-20-08.pdf; 20081211 Response to NRC RAI Letter dtd 11-25-08.pdf; 20081211  
We have one more letter (on drawing issues) that we plan to have out before the holidays. That will probably go out next Thursday.
Bob Vincent X7259 1


Response to NRC RAI Letter dtd 12-1-08.pdfAttached are four RAI response letters that were signed out today. Let me know if you have any questions.
Hearing Identifier:     Prairie_Island_NonPublic Email Number:           189 Mail Envelope Properties     (9FA1D9F2F220C04F95D9394E3CF02DAB013A714F)
We have one more letter (on drawing issues) that we plan to have out before the holidays. That will probably go out next Thursday.
 
Bob Vincent X7259
 
Hearing Identifier: Prairie_Island_NonPublic Email Number: 189   Mail Envelope Properties   (9FA1D9F2F220C04F95D9394E3CF02DAB013A714F)


==Subject:==
==Subject:==
Four PINGP License Renewal RAI Response Letters Sent Date:   12/11/2008 2:48:24 PM Received Date: 12/11/2008 2:48:44 PM From:   Vincent, Robert Created By:   Robert.Vincent@xenuclear.com Recipients:     "Eckholt, Gene F." <Gene.Eckholt@xenuclear.com>
Four PINGP License Renewal RAI Response Letters Sent Date:             12/11/2008 2:48:24 PM Received Date:         12/11/2008 2:48:44 PM From:                   Vincent, Robert Created By:             Robert.Vincent@xenuclear.com Recipients:
Tracking Status: None "Davis, Marlys E." <Marlys.Davis@xenuclear.com>
"Eckholt, Gene F." <Gene.Eckholt@xenuclear.com>
Tracking Status: None "Nathan Goodman" <Nathan.Goodman@nrc.gov> Tracking Status: None "Richard Plasse" <Richard.Plasse@nrc.gov> Tracking Status: None "Stuart Sheldon" <Stuart.Sheldon@nrc.gov> Tracking Status: None Post Office:   enex02.ft.nmcco.net
Tracking Status: None "Davis, Marlys E." <Marlys.Davis@xenuclear.com>
 
Tracking Status: None "Nathan Goodman" <Nathan.Goodman@nrc.gov>
Files     Size     Date & Time MESSAGE   282     12/11/2008 2:48:44 PM 20081211 Response to NRC RAI Letter dtd 11-19-08.pdf   481802 20081211 Response to NRC RAI Letter dtd 11-20-08.pdf   500448 20081211 Response to NRC RAI Letter dtd 11-25-08.pdf   513808 20081211 Response to NRC RAI Letter dtd 12-1-08.pdf   486732 Options Priority:     Standard   Return Notification:   No   Reply Requested:   No   Sensitivity:     Normal Expiration Date:     Recipients Received:      
Tracking Status: None "Richard Plasse" <Richard.Plasse@nrc.gov>
 
Tracking Status: None "Stuart Sheldon" <Stuart.Sheldon@nrc.gov>
Document Control Desk Page 2 Enclosure (1) cc:  Administrator, Region III, USNRC License Renewal Project Manager, Prairie Island, USNRC Resident Inspector, Prairie Island, USNRC Prairie Island Indian Community ATTN:  Phil Mahowald  Minnesota Department of Commerce    NSPM Responses to NRC Requests for Additional Information Dated November 19, 2008 1 RAI 2.3.3.9-1 Section 4.3.1.5 of the Safety Evaluation Report for PINGP Units 1 and 2, dated September 6, 1979, discusses various types of wet pipe, deluge, and pre-action dry pipe sprinkler systems provided in the plant areas for fire suppression activities. The sprinkler systems in various areas are: Fire Sprinkler System Area
Tracking Status: None Post Office:           enex02.ft.nmcco.net Files                           Size                 Date & Time MESSAGE                         282                 12/11/2008 2:48:44 PM 20081211 Response to NRC RAI Letter dtd 11-19-08.pdf                     481802 20081211 Response to NRC RAI Letter dtd 11-20-08.pdf                     500448 20081211 Response to NRC RAI Letter dtd 11-25-08.pdf                     513808 20081211 Response to NRC RAI Letter dtd 12-1-08.pdf               486732 Options Priority:                       Standard Return Notification:             No Reply Requested:                 No Sensitivity:                     Normal Expiration Date:
 
Recipients Received:
Wet Pipe Automatic Sprinkler Systems Turbine Building - Turbine Lube Oil and Control Oil Piping Areas  Air Compressor and Auxiliary Feedwater Pump Rooms  Exit Stairwells  Records Storage Area  Decontamination Area  Water Treatment Area  Warehouse  Hot Lab Area Deluge Systems  Main Auxiliary and Startup Transformers  Turbine Generators Bearings  Turbine Seal Oil Unit  Turbine Lube Oil Reservoir  Oil Storage Room  Charcoal Filter - Auxiliary Building Special Exhaust Filter and the Shield Building
 
Exhaust Filters Pre-action Dry Pipe Sprinkler Systems Containment Cable Penetration Areas  Screen House Pump Area (Both Levels)
Including the Diesel Cooling Water Pumps and the Diesel Driven Fire Pump The staff requests that the applicant verify whether the above sprinkler systems installed in various areas of the plant are in the scope of license renewal in accordance
 
with 10 CFR 54.4(a) and subject to an AMR in accordance with 10 CFR 54.21(a)(1). If they are excluded from the scope of license renewal and not subject to an AMR, the staff requests that the applicant provide justification for the exclusion.
NSPM Response to RAI 2.3.3.9-1 The wet pipe automatic sprinkler, deluge, and pre-action dry pipe sprinkler sub-systems installed in various areas of the plant for fire suppression are in the scope of license    NSPM Responses to NRC Requests for Additional Information Dated November 19, 2008 2renewal in accordance with 10 CFR 54.4(a) and are subject to an Aging Management Review (AMR) in accordance with 10 CFR 54.21(a)(1). Wet Pipe Automatic Sprinkler Systems The Turbine Building - Turbine Lube Oil and Control Oil Piping Areas Sprinkler sub-systems are shown on Drawings LR-39228-2 and 3. See Drawing LR-
 
39228-2, location D-7, Turbine Oil Sprinkler System WPS-18. See Drawing LR-
 
39228-3, location G-4, Turbine Oil Pipe Wet Pipe System WPS-21. The Air Compressor and Auxiliary Feedwater Pump Rooms Sprinkler sub-system is shown on Drawing LR-39228-2, location D-3, Air Compressor and Auxiliary Feedwater Pump Area Sprinkler System WPS-10. Exit stairwells used for egress or to allow access to manual fire suppression are provided with sprinkler systems throughout the plant. Exit stairwell sprinkler
 
systems are shown on Drawings LR-100282 and LR-39228-2, 3, 4 and 5. See Drawing LR-100282, location D-4, Stairs Wet Pipe Sprinkler System. See Drawing LR-39228-2, location E-5, Stairway Sprinkler System SWP-3 (incorrectly


labeled WPS-18), location B-9, Stairway Sprinkler System SWP-5, and location G-9, Stairway Wet Pipe System SWP-6. See Drawing LR-39228-3, location E-2, Stairway Sprinkler System SWP-14 and location H-6, Stairway Sprinkler System
Document Control Desk Page 2 Enclosure (1) cc:
Administrator, Region III, USNRC License Renewal Project Manager, Prairie Island, USNRC Resident Inspector, Prairie Island, USNRC Prairie Island Indian Community ATTN: Phil Mahowald Minnesota Department of Commerce


SWP-13. See Drawing LR-39228-4, location B-4, Stairway Sprinkler System SWP-12, location B-10, Stairway Sprinkler System SWP-4, location F-5, Stairway Sprinkler System SWP-1 and location C-6, Stairway Sprinkler System SWP-2. 
Enclosure 1 NSPM Responses to NRC Requests for Additional Information Dated November 19, 2008 RAI 2.3.3.9-1 Section 4.3.1.5 of the Safety Evaluation Report for PINGP Units 1 and 2, dated September 6, 1979, discusses various types of wet pipe, deluge, and pre-action dry pipe sprinkler systems provided in the plant areas for fire suppression activities. The sprinkler systems in various areas are:
Fire Sprinkler System                 Area Wet Pipe Automatic Sprinkler          x        Turbine Building - Turbine Lube Oil and Systems                                        Control Oil Piping Areas x        Air Compressor and Auxiliary Feedwater Pump Rooms x        Exit Stairwells x        Records Storage Area x        Decontamination Area x        Water Treatment Area x        Warehouse x        Hot Lab Area Deluge Systems                        x        Main Auxiliary and Startup Transformers x        Turbine Generators Bearings x        Turbine Seal Oil Unit x        Turbine Lube Oil Reservoir x        Oil Storage Room x        Charcoal Filter - Auxiliary Building Special Exhaust Filter and the Shield Building Exhaust Filters Pre-action Dry Pipe Sprinkler          x        Containment Cable Penetration Areas Systems                                x        Screen House Pump Area (Both Levels)
Including the Diesel Cooling Water Pumps and the Diesel Driven Fire Pump The staff requests that the applicant verify whether the above sprinkler systems installed in various areas of the plant are in the scope of license renewal in accordance with 10 CFR 54.4(a) and subject to an AMR in accordance with 10 CFR 54.21(a)(1). If they are excluded from the scope of license renewal and not subject to an AMR, the staff requests that the applicant provide justification for the exclusion.
NSPM Response to RAI 2.3.3.9-1 The wet pipe automatic sprinkler, deluge, and pre-action dry pipe sprinkler sub-systems installed in various areas of the plant for fire suppression are in the scope of license 1


See Drawing LR-39228-5, location A-5, Stairwell sprinklers. The Records Storage Area Sprinkler sub-system is shown on Drawing LR-39228-4, location G-8, Record Room System WPS-23. The Decontamination Area at Access Control is protected by a wet pipe sprinkler sub-system shown on Drawing LR-39228-4, location A-8, Laundry Room, Toilet Room, Clothes Storage Room and Corridor Sprinkler Systems WPS-20. The Water Treatment Area Sprinkler sub-system is shown on Drawing LR-39228-2, location E-9, Turbine Room (East Side) Sprinkler System WPS-9. The Warehouse Sprinkler sub-systems are shown on Drawing LR-39228-3. See location B-3, Warehouse Sprinkler & Hose Stations, and location F-9, Warehouse #2 Sprinkler System DE-3. The Hot Lab Area Sprinkler sub-system is shown on Drawing LR-39228-4, location C-6, WPS-19 Hot Chemical Laboratory. NSPM Responses to NRC Requests for Additional Information Dated November 19, 2008 3 Deluge systems The Main, Auxiliary and Startup Transformers Deluge sub-systems are shown on Drawings LR-39228-2 and LR-39228-3. See Drawing LR-39228-2, location B-6, B-7 and B-8, Transformer Sprinkler Systems DM-3, DM-2 and DM-1, respectively. See Drawing LR-39228-3, location D-2, D-4 and D-5, Transformer Sprinkler System DM-5, DM-4 and DM-6, respectively. The Turbine Generator Bearing Pre-Action sub-systems are shown on Drawings LR-39228-2 and LR-39228-3. See Drawing LR-39228-2, location B-10, Turbine Bearing Fire Protection Pre-action System PA-14. See Drawing LR-39228-3, location B-11, Turbine Bearing Fire Protection Pre-action System PA-15. The Turbine Seal Oil Unit Deluge sub-systems are shown on Drawings LR-39228-2 and LR-39228-3.See Drawing LR-39228-2, location D-9, Hydrogen Seal Oil Unit Sprinkler System DA-1. See Drawing LR-39228-3, location G-2, Hydrogen Seal Oil Sprinkler System DA-5. The Turbine Lube Oil Reservoir Deluge sub-systems are shown on Drawings LR-39228-2 and LR-39228-3. See Drawing LR-39228-2, location D-4, Turbine Oil Reservoir Area Sprinkler System DA-3. See Drawing LR-39228-3, location G-6, Turbine Oil Reservoir Sprinkler System DA-4. The Oil Storage Room Deluge sub-system is shown on Drawing LR-39228-2, location B-3, Turbine Oil Storage Room Sprinkler System DA-2. The Charcoal Filter - Auxiliary Building Special Exhaust Filter and the Shield Building Exhaust Filters Deluge sub-systems are shown on Drawing LR-39603-4, location C-4 through E-4 and location E-11 through G-11. Pre-action Dry Pipe Sprinkler Systems The Containment Cable Penetration Area Pre-Action Dry Pipe Sprinkler sub-systems are shown on Drawing LR-39228-4, location C-3, D-5, D-8 and C-10, Electrical Penetration Pre-Action System PAD-7, PAD-6, PAD-3 and PAD-4
Enclosure 1 NSPM Responses to NRC Requests for Additional Information Dated November 19, 2008 renewal in accordance with 10 CFR 54.4(a) and are subject to an Aging Management Review (AMR) in accordance with 10 CFR 54.21(a)(1).
Wet Pipe Automatic Sprinkler Systems x  The Turbine Building - Turbine Lube Oil and Control Oil Piping Areas Sprinkler sub-systems are shown on Drawings LR-39228-2 and 3. See Drawing LR-39228-2, location D-7, Turbine Oil Sprinkler System WPS-18. See Drawing LR-39228-3, location G-4, Turbine Oil Pipe Wet Pipe System WPS-21.
The Air Compressor and Auxiliary Feedwater Pump Rooms Sprinkler sub-system is shown on Drawing LR-39228-2, location D-3, Air Compressor and Auxiliary Feedwater Pump Area Sprinkler System WPS-10.
x  Exit stairwells used for egress or to allow access to manual fire suppression are provided with sprinkler systems throughout the plant. Exit stairwell sprinkler systems are shown on Drawings LR-100282 and LR-39228-2, 3, 4 and 5. See Drawing LR-100282, location D-4, Stairs Wet Pipe Sprinkler System. See Drawing LR-39228-2, location E-5, Stairway Sprinkler System SWP-3 (incorrectly labeled WPS-18), location B-9, Stairway Sprinkler System SWP-5, and location G-9, Stairway Wet Pipe System SWP-6. See Drawing LR-39228-3, location E-2, Stairway Sprinkler System SWP-14 and location H-6, Stairway Sprinkler System SWP-13. See Drawing LR-39228-4, location B-4, Stairway Sprinkler System SWP-12, location B-10, Stairway Sprinkler System SWP-4, location F-5, Stairway Sprinkler System SWP-1 and location C-6, Stairway Sprinkler System SWP-2.
See Drawing LR-39228-5, location A-5, Stairwell sprinklers.
x  The Records Storage Area Sprinkler sub-system is shown on Drawing LR-39228-4, location G-8, Record Room System WPS-23.
The Decontamination Area at Access Control is protected by a wet pipe sprinkler sub-system shown on Drawing LR-39228-4, location A-8, Laundry Room, Toilet Room, Clothes Storage Room and Corridor Sprinkler Systems WPS-20.
The Water Treatment Area Sprinkler sub-system is shown on Drawing LR-39228-2, location E-9, Turbine Room (East Side) Sprinkler System WPS-9.
The Warehouse Sprinkler sub-systems are shown on Drawing LR-39228-3. See location B-3, Warehouse Sprinkler & Hose Stations, and location F-9, Warehouse #2 Sprinkler System DE-3.
The Hot Lab Area Sprinkler sub-system is shown on Drawing LR-39228-4, location C-6, WPS-19 Hot Chemical Laboratory.
2


respectively. The Screen House Pump Area (Both Levels) Including the Diesel Cooling Water Pumps and the Diesel Driven Fire Pump Pre-action Dry Pipe Sprinkler sub-system is shown on Drawing LR-39228-3, location B-8, Screenhouse Sprinkler  
Enclosure 1 NSPM Responses to NRC Requests for Additional Information Dated November 19, 2008 Deluge systems x  The Main, Auxiliary and Startup Transformers Deluge sub-systems are shown on Drawings LR-39228-2 and LR-39228-3. See Drawing LR-39228-2, location B-6, B-7 and B-8, Transformer Sprinkler Systems DM-3, DM-2 and DM-1, respectively. See Drawing LR-39228-3, location D-2, D-4 and D-5, Transformer Sprinkler System DM-5, DM-4 and DM-6, respectively.
x  The Turbine Generator Bearing Pre-Action sub-systems are shown on Drawings LR-39228-2 and LR-39228-3. See Drawing LR-39228-2, location B-10, Turbine Bearing Fire Protection Pre-action System PA-14. See Drawing LR-39228-3, location B-11, Turbine Bearing Fire Protection Pre-action System PA-15.
x  The Turbine Seal Oil Unit Deluge sub-systems are shown on Drawings LR-39228-2 and LR-39228-3. See Drawing LR-39228-2, location D-9, Hydrogen Seal Oil Unit Sprinkler System DA-1. See Drawing LR-39228-3, location G-2, Hydrogen Seal Oil Sprinkler System DA-5.
x  The Turbine Lube Oil Reservoir Deluge sub-systems are shown on Drawings LR-39228-2 and LR-39228-3. See Drawing LR-39228-2, location D-4, Turbine Oil Reservoir Area Sprinkler System DA-3. See Drawing LR-39228-3, location G-6, Turbine Oil Reservoir Sprinkler System DA-4.
x  The Oil Storage Room Deluge sub-system is shown on Drawing LR-39228-2, location B-3, Turbine Oil Storage Room Sprinkler System DA-2.
x  The Charcoal Filter - Auxiliary Building Special Exhaust Filter and the Shield Building Exhaust Filters Deluge sub-systems are shown on Drawing LR-39603-4, location C-4 through E-4 and location E-11 through G-11.
Pre-action Dry Pipe Sprinkler Systems x  The Containment Cable Penetration Area Pre-Action Dry Pipe Sprinkler sub-systems are shown on Drawing LR-39228-4, location C-3, D-5, D-8 and C-10, Electrical Penetration Pre-Action System PAD-7, PAD-6, PAD-3 and PAD-4 respectively.
The Screen House Pump Area (Both Levels) Including the Diesel Cooling Water Pumps and the Diesel Driven Fire Pump Pre-action Dry Pipe Sprinkler sub-system is shown on Drawing LR-39228-3, location B-8, Screenhouse Sprinkler System PAD-9.
The scoping boundaries extend up to and include the installed end devices such as sprinkler heads and spray nozzles. The interconnected piping/fittings, valves, sprinkler heads, spray nozzles and in-line components are within the scope of License Renewal and subject to AMR. Piping/fittings, valves, sprinkler heads, spray nozzles and other in-3


System PAD-9.
Enclosure 1 NSPM Responses to NRC Requests for Additional Information Dated November 19, 2008 line components are included in LRA Table 2.3.3-9, and AMR aging management evaluations are included in Table 3.3.2-9.
The scoping boundaries extend up to and include the installed end devices such as sprinkler heads and spray nozzles. The interconnected piping/fittings, valves, sprinkler heads, spray nozzles and in-line components are within the scope of License Renewal and subject to AMR. Piping/fittings, valves, sprinkler heads, spray nozzles and other in-  NSPM Responses to NRC Requests for Additional Information Dated November 19, 2008 4 line components are included in LRA Table 2.3.3-9, and AMR aging management evaluations are included in Table 3.3.2-9.
RAI 2.3.3.9-2 LRA Tables 2.3.3-9 and 3.3.2-9 exclude several types of fire protection components that appear on the LRA drawings as within the scope of license renewal or discussed in PINGP CLB documents. These components are listed below:
RAI 2.3.3.9-2 LRA Tables 2.3.3-9 and 3.3.2-9 exclude several types of fire protection components that appear on the LRA drawings as within the scope of license renewal or discussed in PINGP CLB documents. These components are listed below: hose connections interior fire hose stations pipe supports  
* hose connections
* interior fire hose stations
* pipe supports
* couplings
* dikes for oil spill confinement
* floor drains and curbs for fire-fighting water
* backflow prevention devices
* trash grids and traveling screens
* flame retardant coating for cables
* fire retardant intumescent coating for polyurethane foam insulation
* turbine building smoke removal system components
* air compressors for safe-shutdown operations For each, determine whether the component should be included in Tables 2.3.3-9 and 3.3.2-9 as component types subject to an AMR, and if not, justify the exclusion.
NSPM Response to RAI 2.3.3.9-2 Fire protection hose connections are within the scope of License Renewal. Hose connections from the plant fire header, hydrants and valves are evaluated as Piping/Fittings and are included in LRA Table 2.3.3-9 and Table 3.3.2-9. Fire hoses, including integral hose connections, are evaluated in LRA Section 2.1.3.2.2. Fire hoses are inspected and tested periodically and must be replaced if they do not pass the test or inspection; these components are short lived and are not subject to Aging Management Review.
Interior fire hose stations are within the scope of License Renewal. Interior fire hose stations components are evaluated as Piping/Fittings and Valves and are included in LRA Table 2.3.3-9 and Table 3.3.2-9.
Pipe supports for fire protection piping are within the scope of License Renewal. See LRA Section 2.4.2 and Table 2.4.2-1 for supports, and Section 2.3.3.9 and Table 2.3.3-9 for fire protection piping. For additional detail and for aging management of fire protection pipe supports, see Table 3.5.2-2 for the component type, Support (... non-ASME piping ...).
4


couplings dikes for oil spill confinement floor drains and curbs for fire-fighting water backflow prevention devices trash grids and traveling screens flame retardant coating for cables fire retardant intumescent coating for polyurethane foam insulation turbine building smoke removal system components air compressors for safe-shutdown operations For each, determine whether the component should be included in Tables 2.3.3-9 and 3.3.2-9 as component types subject to an AMR, and if not, justify the exclusion.
Enclosure 1 NSPM Responses to NRC Requests for Additional Information Dated November 19, 2008 Fire header couplings are within the scope of License Renewal. Fire header couplings are evaluated as Piping/Fittings and are included in LRA Table 2.3.3-9 and Table 3.3.2-9.
NSPM Response to RAI 2.3.3.9-2 Fire protection hose connections are within the scope of License Renewal. Hose connections from the plant fire header, hydrants and valves are evaluated as Piping/Fittings and are included in LRA Table 2.3.3-9 and Table 3.3.2-9. Fire hoses, including integral hose connections, are evaluated in LRA Section 2.1.3.2.2. Fire hoses are inspected and tested periodically and must be replaced if they do not pass the test
Dikes for oil spill confinement are addressed by the component types, Concrete (...
curbs, walls, slabs ...)" and Steel components (... angles used to contain fuel oil leaks
...)." These component types, as used in the PINGP LRA, include structures that provide intended functions to direct flow and/or provide a fire barrier to prevent the spread of flammable liquids. These components are in scope of License Renewal and protect safety related structures and safe shutdown systems from fire damage.
Concrete floor depressions, part of the concrete slab design, are also used to direct the flow of flammable liquids. These components are located throughout safety related structures and can be found in LRA Tables 2.4.1-1, 2.4.4-1, 2.4.5-1, and 2.4.9-1. For aging management of these concrete and steel components, see LRA Tables 3.5.2-1, 3.5.2-4, 3.5.2-5, and 3.5.2-9.
There is a reinforced concrete wall surrounding the fuel oil receiving tank located outside, adjacent to the south wall of the D5/D6 Diesel Generator Building. However the wall is not in scope of License Renewal. Since the tank performs a support function and not a confinement function, it is not in scope of License Renewal.
Floor drains for fire fighting water are within the scope of License Renewal and are evaluated in the Waste Disposal (WD) System. In general floor drains are highlighted as within the scope of License Renewal per 10 CFR 54.4(a)(2) due to flooding and/or spatial interaction intended functions. Where they may also have an 10 CFR 54.4(a)(3) function, this was not differentiated (for example, see Drawing LR-39248). The Turbine Oil Reservoir and Oil Storage Room drains are specifically discussed in Section 4.5 of the Safety Evaluation Report dated September 9, 1979. These drains are depicted on Drawings LR-39231-1, locations G-3 and H-8, and LR-39231-2, location H-4; and should be highlighted as within the scope of License Renewal per 10 CFR 54.4(a)(3).
Floor drains are evaluated as Piping/Fittings and are included in LRA Table 2.3.3-20 and Table 3.3.2-20. The following changes are required to the LRA:
In LRA Section 2.3.3.20 under System Function Listing, the following function is added:
Code WD-FP                                    Cri 1 Cri 2                 Cri 3 Contains SCs relied upon in safety analysis                    FP EQ PTS AT SB or plant evaluations to perform a function                      X that demonstrates compliance with 10 CFR 50.48, Fire Protection.
Comment: This system contains floor drains for fire fighting water and oil confinement, such as the Turbine Oil Reservoir and Oil Storage Room drains, that support a Fire Protection function.
5


or inspection; these components are short lived and are not subject to Aging Management Review. Interior fire hose stations are within the scope of License Renewal. Interior fire hose stations components are evaluated as Piping/Fittings and Valves and are included in
Enclosure 1 NSPM Responses to NRC Requests for Additional Information Dated November 19, 2008 In LRA Section 2.3.3.20 on Page 2.3-109, second paragraph, second sentence, "plant floor drains," is added to the list of drains which comprise the Waste Liquid sub-system.
 
In LRA Section 2.3.3.20, Page 2.3-110, the third sentence of the fifth paragraph is revised to read as follows: Portions of the WD System support Fire Protection or Station Blackout event requirements based on the criteria of 10 CFR 54.4(a)(3).
LRA Table 2.3.3-9 and Table 3.3.2-9. Pipe supports for fire protection piping are within the scope of License Renewal. See LRA Section 2.4.2 and Table 2.4.2-1 for supports, and Section 2.3.3.9 and Table 2.3.3-9 for fire protection piping. For additional detail and for aging management of fire protection pipe supports, see Table 3.5.2-2 for the component type, "Support (... non-
Curbs for fire fighting water are addressed by the component types, Concrete (... walls, slabs and curbs ...), Stainless steel components (... curbs and flow deflectors ...), and Steel components (... curbs ...). These component types as used in the PINGP LRA include structures that provide an intended function to direct flow away from safety related equipment in order to prevent water damage. These components are in scope of License Renewal, and are located throughout safety related structures. They are included in LRA Tables 2.4.1-1, 2.4.4-1, 2.4.7-1, and 2.4.9-1. For aging management of these concrete, stainless steel, and steel components, see LRA Tables 3.5.2-1, 3.5.2-4, 3.5.2-7, and 3.5.2-9.
 
ASME piping ...)."      NSPM Responses to NRC Requests for Additional Information Dated November 19, 2008 5Fire header couplings are within the scope of License Renewal. Fire header couplings are evaluated as Piping/Fittings and are included in LRA Table 2.3.3-9 and Table 3.3.2-
 
9.Dikes for oil spill confinement are addressed by the component types, "Concrete (...
curbs, walls, slabs ...)" and "Steel components (... angles used to contain fuel oil leaks
...)."  These component types, as used in the PINGP LRA, include structures that provide intended functions to direct flow and/or provide a fire barrier to prevent the spread of flammable liquids. These components are in scope of License Renewal and protect safety related structures and safe shutdown systems from fire damage.
Concrete floor depressions, part of the concrete slab design, are also used to direct the flow of flammable liquids. These components are located throughout safety related
 
structures and can be found in LRA Tables 2.4.1-1, 2.4.4-1, 2.4.5-1, and 2.4.9-1. For
 
aging management of these concrete and steel components, see LRA Tables 3.5.2-1, 3.5.2-4, 3.5.2-5, and 3.5.2-9.There is a reinforced concrete wall surrounding the fuel oil receiving tank located outside, adjacent to the south wall of the D5/D6 Diesel Generator Building. However the wall is not in scope of License Renewal. Since the tank performs a support function and not a confinement function, it is not in scope of License Renewal.
Floor drains for fire fighting water are within the scope of License Renewal and are evaluated in the Waste Disposal (WD) System. In general floor drains are highlighted as within the scope of License Renewal per 10 CFR 54.4(a)(2) due to flooding and/or spatial interaction intended functions. Where they may also have an 10 CFR 54.4(a)(3) function, this was not differentiated (for example, see Drawing LR-39248). The Turbine Oil Reservoir and Oil Storage Room drains are specifically discussed in Section 4.5 of the Safety Evaluation Report dated September 9, 1979. These drains are depicted on Drawings LR-39231-1, locations G-3  and H-8, and LR-39231-2, location H-4; and should be highlighted as within the scope of License Renewal per 10 CFR 54.4(a)(3).
Floor drains areevaluated as Piping/Fittings and are included in LRA Table 2.3.3-20 and Table 3.3.2-20. The following changes are required to the LRA:  In LRA Section 2.3.3.20 under System Function Listing, the following function is added: Cri 3 Cri 1 Cri 2 FP EQ PTS ATSBCode WD-FP Contains SCs relied upon in safety analysis or plant evaluations to perform a function that demonstrates compliance with 10 CFR 50.48, Fire Protection. X    Comment: This system contains floor drains for fire fighting water and oil confinement, such as the Turbine Oil Reservoir and Oil Storage Room drains, that support a Fire Protection function. NSPM Responses to NRC Requests for Additional Information Dated November 19, 2008 6In LRA Section 2.3.3.20 on Page 2.3-109, second paragraph, second sentence, "plant floor drains," is added to the list of drains which comprise the Waste Liquid  
 
sub-system.In LRA Section 2.3.3.20, Page 2.3-110, the third sentence of the fifth paragraph is revised to read as follows: "Portions of the WD System support Fire Protection or  
 
Station Blackout event requirements based on the criteria of 10 CFR 54.4(a)(3)."Curbs for fire fighting water are addressed by the component types, "Concrete (... walls, slabs and curbs ...)," "Stainless steel components (... curbs and flow deflectors ...)," and  
 
"Steel components (... curbs ...).These component types as used in the PINGP LRA  
 
include structures that provide an intended function to direct flow away from safety related equipment in order to prevent water damage. These components are in scope  
 
of License Renewal, and are located throughout safety related structures. They are  
 
included in LRA Tables 2.4.1-1, 2.4.4-1, 2.4.7-1, and 2.4.9-1. For aging management of these concrete, stainless steel, and steel components, see LRA Tables 3.5.2-1, 3.5.2-4, 3.5.2-7, and 3.5.2-9.
The PINGP Fire Protection (FP) System is supplied from the Mississippi River and does not include connections from potable water sources. Therefore, the PINGP FP system does not contain backflow prevention devices; as a result they are not included in LRA Table 2.3.3-9 and Table 3.3.2-9. The FP system does include check valves; these are included in LRA Table 2.3.3-9 and Table 3.3.2-9.
The PINGP Fire Protection (FP) System is supplied from the Mississippi River and does not include connections from potable water sources. Therefore, the PINGP FP system does not contain backflow prevention devices; as a result they are not included in LRA Table 2.3.3-9 and Table 3.3.2-9. The FP system does include check valves; these are included in LRA Table 2.3.3-9 and Table 3.3.2-9.
Trash grids and traveling screens are addressed in LRA Section 2.3.4.3, Circulating Water (CW) System. The FP pumps draw water from behind the Plant Screenhouse  
Trash grids and traveling screens are addressed in LRA Section 2.3.4.3, Circulating Water (CW) System. The FP pumps draw water from behind the Plant Screenhouse trash grids and screens. During emergency operation, when the circulating water pumps are not in-service, the flows through the trash grids and screens would be insignificant and plugging or failure of the grids and screens is not credible. Therefore, trash grids and traveling screens are not relied upon to perform or support a License Renewal Fire Protection-related Intended Function.
 
Flame retardant coatings for cables used in penetration seals and used for cable encapsulation are in scope of License Renewal. They are included in LRA Table 2.4.5-
trash grids and screens. During emergency operation, when the circulating water pumps are not in-service, the flows through the trash grids and screens would be insignificant and plugging or failure of the grids and screens is not credible. Therefore, trash grids and traveling screens are not relied upon to perform or support a License  
: 1. For additional detail and for aging management of flame retardant coating for cables, see LRA Table 3.5.2-5 for the component types, Fire barrier penetration seals and Fireproofing for cable and cable tray.
 
Fire retardant intumescent coatings were originally used on all polyurethane foam piping insulation in areas containing safety related equipment. However, the intumescent coating performed unsatisfactorily and was replaced with materials identified as Armaflex (primer) and Flammastic (mastic sealant) which have better flame spread and smoke density test results when compared to the intumescent coating. This was conveyed in a letter to the NRC dated May 4, 1992. The NRC approved the replacement materials in a letter dated January 14, 1993. These components are in scope of License Renewal, and are identified in Table 2.4.5-1 of the LRA as, Fire 6
Renewal Fire Protection-related Intended Function. Flame retardant coatings for cables used in penetration seals and used for cable encapsulation are in scope of License Renewal. They are included in LRA Table 2.4.5-
: 1. For additional detail and for aging management of flame retardant coating for cables, see LRA Table 3.5.2-5 for the component types, "Fire barrier penetration seals" and  
 
"Fireproofing" for cable and cable tray.Fire retardant intumescent coatings were originally used on all polyurethane foam piping insulation in areas containing safety related equipment. However, the intumescent coating performed unsatisfactorily and was replaced with materials identified as Armaflex (primer) and Flammastic (mastic sealant) which have better flame spread and  
 
smoke density test results when compared to the intumescent coating. This was  
 
conveyed in a letter to the NRC dated May 4, 1992. The NRC approved the replacement materials in a letter dated January 14, 1993. These components are in  
 
scope of License Renewal, and are identified in Table 2.4.5-1 of the LRA as, "Fire    NSPM Responses to NRC Requests for Additional Information Dated November 19, 2008 7barrier penetration seals" and "Fireproofing" components. LRA Table 3.5.2-5 provides additional information on these component types and materials. Turbine building roof exhaust fans, as well as smoke hatches that are fitted with automatic releases, are within the scope of License Renewal. The Turbine building roof exhaust fans are evaluated in LRA Section 2.3.3.19, Turbine and Administration Building (ZB) System (see Function ZB-FP) and are shown on Drawing LR-39601, location F-2, Turbine Building Roof Vent Fans. The fan and damper are integral to the fan housing and are evaluated as Fan Housings. They are included in LRA Table 2.3.3-
 
19 and Table 3.3.2-19. The Turbine Building smoke hatches are evaluated in LRA
 
Table 3.5.2-5
.Air compressors required for Fire Protection safe-shutdown operation are within the scope of License Renewal. The station and instrument air compressors are evaluated in LRA Section 2.3.3.17, Station and Instrument Air (SA) System (see Function SA-FP) and are shown on Drawings LR-39244 and LR-39253-3. The air compressors are active components and not subject to aging management review; as a result they are
 
not included in LRA Table 2.3.3-17. 
 
Document Control Desk Page 2 Enclosure (1) cc:  Administrator, Region III, USNRC License Renewal Project Manager, Prairie Island, USNRC Resident Inspector, Prairie Island, USNRC Prairie Island Indian Community ATTN:  Phil Mahowald  Minnesota Department of Commerce    NSPM Responses to NRC Requests for Additional Information Dated November 20, 2008 1 RAI 4.7.1-1 Discuss the inspection history and results of the piping that has been approved for leak-before-break (LBB) at Prairie Island Units 1 and 2. Discuss the future inspection plans.
NSPM Response to RAI 4.7.1-1The PINGP piping that has been approved for leak-before-break (LBB) includes the Unit 1 and Unit 2 primary loop (large-bore) piping and the Unit 1 pressurizer surge line. The associated piping and nozzle welds have been periodically examined in accordance with the requirements of ASME Section XI. A review of the past examination history dating back to the beginning of the third inservice inspection interval, which began December 17, 1993 for Unit 1 and December 21, 1994 for Unit 2, indicates that the
 
piping was examined using surface and volumetric inspection techniques. A review of the surface examination results found that some minor surface indications (e.g., small
 
rounded and linear indications) were identified. These indications were evaluated and dispositioned per the requirements of ASME Section XI. Some indications were removed (e.g., by light buffing), while others were found acceptable per Code, and left in place. A review of the volumetric examination results found that some geometric indications were identified but no volumetric indications required corrective action or
 
repair/replacement.
This piping is currently subject to examination in accordance with ASME Section XI, 1998 Edition, including the 1998, 1999 and 2000 Addenda, and the approved Risk
 
Informed Inservice Inspection (RI-ISI) Program. These examinations will continue until
 
the end of the current (fourth) inspection interval. Under the current program, the associated piping and nozzle welds are volumetrically examined. Following completion of the current inspection interval, the PINGP ASME Section XI Inservice Inspection, Subsections IWB, IWC, and IWD Program will be updated as required by 10 CFR 50.55a, and examinations will be conducted accordingly. In addition, future examinations of the cast austenitic stainless steel piping in the Unit 1 and 2 reactor coolant loops may also include enhanced volumetric examinations or component-specific flaw tolerance evaluations as deemed appropriate per the new Thermal Aging


Embrittlement of Cast Austenitic Stainless Steel Program.
Enclosure 1 NSPM Responses to NRC Requests for Additional Information Dated November 19, 2008 barrier penetration seals and Fireproofing components. LRA Table 3.5.2-5 provides additional information on these component types and materials.
RAI 4.7.1-2 In Section 4.7.1, second paragraph, the applicant stated that primary coolant piping is made of cast austenitic stainless steel (CASS). In the fourth paragraph, the applicant stated that CASS is used in the pipe fittings. (a) Confirm that pipe fittings and straight
Turbine building roof exhaust fans, as well as smoke hatches that are fitted with automatic releases, are within the scope of License Renewal. The Turbine building roof exhaust fans are evaluated in LRA Section 2.3.3.19, Turbine and Administration Building (ZB) System (see Function ZB-FP) and are shown on Drawing LR-39601, location F-2, Turbine Building Roof Vent Fans. The fan and damper are integral to the fan housing and are evaluated as Fan Housings. They are included in LRA Table 2.3.3-19 and Table 3.3.2-19. The Turbine Building smoke hatches are evaluated in LRA Table 3.5.2-5.
Air compressors required for Fire Protection safe-shutdown operation are within the scope of License Renewal. The station and instrument air compressors are evaluated in LRA Section 2.3.3.17, Station and Instrument Air (SA) System (see Function SA-FP) and are shown on Drawings LR-39244 and LR-39253-3. The air compressors are active components and not subject to aging management review; as a result they are not included in LRA Table 2.3.3-17.
7


sections of the primary coolant piping at Units 1 and 2 are all made of CASS.  (b)
Document Control Desk Page 2 Enclosure (1) cc:
Discuss the material used in fabricating the surge lines at Units 1 and 2. NSPM Responses to NRC Requests for Additional Information Dated November 20, 2008 2 NSPM Response to RAI 4.7.1-2 (a) The Unit 1 large bore primary coolant piping fittings (elbows) are fabricated from cast austenitic stainless steel (CASS) (i.e., ASTM A351). The Unit 1 large bore primary
Administrator, Region III, USNRC License Renewal Project Manager, Prairie Island, USNRC Resident Inspector, Prairie Island, USNRC Prairie Island Indian Community ATTN: Phil Mahowald Minnesota Department of Commerce


coolant piping straight sections are made from forgings (i.e., ASTM A376). All Unit 2 large bore primary coolant piping fittings and straight sections are fabricated from CASS (i.e., ASTM A351). (b) The Unit 1 pressurizer surge line piping fittings and straight sections are fabricated from forged product forms (i.e.; ASTM A376, A403). The Unit 2 pressurizer surge line
Enclosure 1 NSPM Responses to NRC Requests for Additional Information Dated November 20, 2008 RAI 4.7.1-1 Discuss the inspection history and results of the piping that has been approved for leak-before-break (LBB) at Prairie Island Units 1 and 2. Discuss the future inspection plans.
NSPM Response to RAI 4.7.1-1 The PINGP piping that has been approved for leak-before-break (LBB) includes the Unit 1 and Unit 2 primary loop (large-bore) piping and the Unit 1 pressurizer surge line. The associated piping and nozzle welds have been periodically examined in accordance with the requirements of ASME Section XI. A review of the past examination history dating back to the beginning of the third inservice inspection interval, which began December 17, 1993 for Unit 1 and December 21, 1994 for Unit 2, indicates that the piping was examined using surface and volumetric inspection techniques. A review of the surface examination results found that some minor surface indications (e.g., small rounded and linear indications) were identified. These indications were evaluated and dispositioned per the requirements of ASME Section XI. Some indications were removed (e.g., by light buffing), while others were found acceptable per Code, and left in place. A review of the volumetric examination results found that some geometric indications were identified but no volumetric indications required corrective action or repair/replacement.
This piping is currently subject to examination in accordance with ASME Section XI, 1998 Edition, including the 1998, 1999 and 2000 Addenda, and the approved Risk Informed Inservice Inspection (RI-ISI) Program. These examinations will continue until the end of the current (fourth) inspection interval. Under the current program, the associated piping and nozzle welds are volumetrically examined. Following completion of the current inspection interval, the PINGP ASME Section XI Inservice Inspection, Subsections IWB, IWC, and IWD Program will be updated as required by 10 CFR 50.55a, and examinations will be conducted accordingly. In addition, future examinations of the cast austenitic stainless steel piping in the Unit 1 and 2 reactor coolant loops may also include enhanced volumetric examinations or component-specific flaw tolerance evaluations as deemed appropriate per the new Thermal Aging Embrittlement of Cast Austenitic Stainless Steel Program.
RAI 4.7.1-2 In Section 4.7.1, second paragraph, the applicant stated that primary coolant piping is made of cast austenitic stainless steel (CASS). In the fourth paragraph, the applicant stated that CASS is used in the pipe fittings. (a) Confirm that pipe fittings and straight sections of the primary coolant piping at Units 1 and 2 are all made of CASS. (b)
Discuss the material used in fabricating the surge lines at Units 1 and 2.
1


piping fittings and straight sections are fabricated from forged product forms (i.e.; ASTM  
Enclosure 1 NSPM Responses to NRC Requests for Additional Information Dated November 20, 2008 NSPM Response to RAI 4.7.1-2 (a) The Unit 1 large bore primary coolant piping fittings (elbows) are fabricated from cast austenitic stainless steel (CASS) (i.e., ASTM A351). The Unit 1 large bore primary coolant piping straight sections are made from forgings (i.e., ASTM A376). All Unit 2 large bore primary coolant piping fittings and straight sections are fabricated from CASS (i.e., ASTM A351).
 
(b) The Unit 1 pressurizer surge line piping fittings and straight sections are fabricated from forged product forms (i.e.; ASTM A376, A403). The Unit 2 pressurizer surge line piping fittings and straight sections are fabricated from forged product forms (i.e.; ASTM A376, A403).
A376, A403).
RAI 4.7.1-3 The applicant submitted LBB analyses for the Unit 1 pressurizer surge line. Confirm that LBB has not been implemented and LBB analyses have not been submitted to the NRC for the Unit 2 pressurizer surge line.
RAI 4.7.1-3The applicant submitted LBB analyses for the Unit 1 pressurizer surge line. Confirm that LBB has not been implemented and LBB analyses have not been submitted to the  
 
NRC for the Unit 2 pressurizer surge line.
NSPM Response to RAI 4.7.1-3 Leak-Before-Break (LBB) technology has not been implemented and LBB analyses have not been submitted to the NRC for the PINGP Unit 2 pressurizer surge line.
NSPM Response to RAI 4.7.1-3 Leak-Before-Break (LBB) technology has not been implemented and LBB analyses have not been submitted to the NRC for the PINGP Unit 2 pressurizer surge line.
RAI 4.7.1-4Nickel-based Alloy 600/82/182 material in the pressurized water reactor environment has been shown to be susceptible to primary water stress corrosion cracking (PWSCC).
RAI 4.7.1-4 Nickel-based Alloy 600/82/182 material in the pressurized water reactor environment has been shown to be susceptible to primary water stress corrosion cracking (PWSCC).
(a) Identify any piping that has been approved for LBB for both units which contain Alloy 82/182 weld metal and Alloy 600 components. (b) If LBB piping contains Alloy  
(a) Identify any piping that has been approved for LBB for both units which contain Alloy 82/182 weld metal and Alloy 600 components. (b) If LBB piping contains Alloy 600/82/182 material, discuss any mitigation measures (such as weld overlays or mechanical stress improvement) that have been or will be implemented to reduce the effects of PWSCC on the LBB piping components. (c) Discuss the inspection history and future inspection frequency of the Alloy 81/182 dissimilar metal butt welds (see Question number 1 above).
 
NSPM Response to RAI 4.7.1-4 (a) PINGP has no piping that has been approved for Leak-Before-Break (LBB) which contains Alloy 82/182 weld metal or Alloy 600 components. Note that the Unit 2 pressurizer surge nozzle-to-safe end dissimilar metal weld is constructed of Alloy 82; however, this piping has not been approved for LBB.
600/82/182 material, discuss any mitigation measures (such as weld overlays or mechanical stress improvement) that have been or will be implemented to reduce the effects of PWSCC on the LBB piping components. (c) Discuss the inspection history and future inspection frequency of the Alloy 81/182 dissimilar metal butt welds (see  
(b) As previously stated, the LBB piping at PINGP does not contain any Alloy 600/82/182 material. However, to mitigate the effects of primary water stress corrosion 2
 
Question number 1 above).
NSPM Response to RAI 4.7.1-4 (a) PINGP has no piping that has been approved for Leak-Before-Break (LBB) which contains Alloy 82/182 weld metal or Alloy 600 components. Note that the Unit 2  
 
pressurizer surge nozzle-to-safe end dissimilar metal weld is constructed of Alloy 82;  
 
however, this piping has not been approved for LBB. (b) As previously stated, the LBB piping at PINGP does not contain any Alloy 600/82/182 material. However, to mitigate the effects of primary water stress corrosion   NSPM Responses to NRC Requests for Additional Information Dated November 20, 2008 3cracking (PWSCC) on the Unit 2 pressurizer surge nozzle weld, a full structural weld
 
overlay (FSWOL) on the pressurizer surge nozzle-to-safe end dissimilar metal and safe end-to-reducer stainless steel butt welds was recently installed during the PINGP Unit 2 refueling outage (2R25). The NRC authorized the installation of the FSWOL in a letter
 
dated June 15, 2008 [ML081360646]. (c) The only Alloy 82/182 dissimilar metal butt weld in the pressurized water reactor environment at PINGP is the Unit 2 pressurizer surge nozzle-to-safe end dissimilar metal weld. This weld is located on the Unit 2 pressurizer surge line; this piping has not
 
been approved for Leak-Before-Break (LBB).
The PlNGP Unit 2 pressurizer surge nozzle-to-safe end weld was ultrasonically examined in November 2006 per ASME Section XI, Appendix VIII, Supplement 10. The


examination met the ASME Section XI and EPRI MRP-139, "Primary System Piping Butt Weld Inspection and Evaluation Guidelines" requirements for examination coverage. No PWSCC indications were detected. Ultrasonic examinations of the Unit 2 surge nozzle-to-safe end dissimilar metal weld were conducted in September 2008, prior to installation of the full structural weld overlay (FSWOL). The examinations were performed in accordance with ASME  
Enclosure 1 NSPM Responses to NRC Requests for Additional Information Dated November 20, 2008 cracking (PWSCC) on the Unit 2 pressurizer surge nozzle weld, a full structural weld overlay (FSWOL) on the pressurizer surge nozzle-to-safe end dissimilar metal and safe end-to-reducer stainless steel butt welds was recently installed during the PINGP Unit 2 refueling outage (2R25). The NRC authorized the installation of the FSWOL in a letter dated June 15, 2008 [ML081360646].
 
(c) The only Alloy 82/182 dissimilar metal butt weld in the pressurized water reactor environment at PINGP is the Unit 2 pressurizer surge nozzle-to-safe end dissimilar metal weld. This weld is located on the Unit 2 pressurizer surge line; this piping has not been approved for Leak-Before-Break (LBB).
Section XI, Appendix VIII, Supplement 10. No recordable indications were identified.
The PlNGP Unit 2 pressurizer surge nozzle-to-safe end weld was ultrasonically examined in November 2006 per ASME Section XI, Appendix VIII, Supplement 10. The examination met the ASME Section XI and EPRI MRP-139, "Primary System Piping Butt Weld Inspection and Evaluation Guidelines" requirements for examination coverage. No PWSCC indications were detected.
Ultrasonic examinations of the Unit 2 surge nozzle-to-safe end dissimilar metal weld were conducted in September 2008, prior to installation of the full structural weld overlay (FSWOL). The examinations were performed in accordance with ASME Section XI, Appendix VIII, Supplement 10. No recordable indications were identified.
In October 2008, following installation of the FSWOL, ultrasonic examinations (UT) were performed of the new overlay weld and the nozzle-to-safe end dissimilar metal weld.
In October 2008, following installation of the FSWOL, ultrasonic examinations (UT) were performed of the new overlay weld and the nozzle-to-safe end dissimilar metal weld.
100 percent of the Code required volume was achieved during the examinations. The  
100 percent of the Code required volume was achieved during the examinations. The UT examinations resulted in no recordable indications.
 
In a letter dated January 15, 2008 [ML081510906], NSPM proposed alternative requirements to ASME Section XI to provide for the installation and examination of the FSWOL in Alternative Request No. 2-RR-4-8, Revision 1. The NRC staff authorized the use of Alternative Request 2-RR-4-8, Revision 1, in a letter dated June 15, 2008
UT examinations resulted in no recordable indications.
In a letter dated January 15, 2008 [ML081510906], NSPM proposed alternative requirements to ASME Section XI to provide for the installation and examination of the  
 
FSWOL in Alternative Request No. 2-RR-4-8, Revision 1. The NRC staff authorized the  
 
use of Alternative Request 2-RR-4-8, Revision 1, in a letter dated June 15, 2008  
[ML081360646]. Enclosure 2, Table 2 of Alternative Request 2-RR-4-8, Revision 1, requires inservice examinations to be conducted ultrasonically with the examination volume defined in ASME Section XI, Nonmandatory Appendix Q, Figure Q-4300-1.
[ML081360646]. Enclosure 2, Table 2 of Alternative Request 2-RR-4-8, Revision 1, requires inservice examinations to be conducted ultrasonically with the examination volume defined in ASME Section XI, Nonmandatory Appendix Q, Figure Q-4300-1.
Inservice examinations as described in Q-4300 will be performed in accordance with the  
Inservice examinations as described in Q-4300 will be performed in accordance with the requirements of MRP-139, with the additional requirement of at least one ultrasonic examination within ten years of the FSWOL application. Additionally, by letter dated May 7, 2008 [ML081280890], NSPM agreed that if indications were found in the pre-application ultrasonic examination, the first inservice examination will be performed during the first or second outage following FSWOL application. The MRP-139 guidance for ISI goes beyond current ASME Code inspection requirements for PINGP Unit 2.
The NRC found that the inservice examination requirements in the May 7, 2008 letter, and Enclosure 2, Table 2 of Alternative Request 2-RR-4-8, Revision 1, were consistent with, or more conservative than, the ASME Code, Section XI, Appendix Q.
3


requirements of MRP-139, with the additional requirement of at least one ultrasonic examination within ten years of the FSWOL application. Additionally, by letter dated May 7, 2008 [ML081280890], NSPM agreed that if indications were found in the pre-application ultrasonic examination, the first inservice examination will be performed
Enclosure 1 NSPM Responses to NRC Requests for Additional Information Dated November 20, 2008 RAI 4.7.1-5 The applicant discusses Aging Management Program (AMP) B.2.1.41, Thermal Aging Embrittlement Of Cast Austenitic Stainless Steel (CASS), in Appendix B of the license renewal application. However, Section 4.7.1 does not mention this AMP for managing the LBB piping that is made of CASS. Discuss how CASS material of the LBB piping will be managed because AMP B.2.1.41 does not seem to be used to monitor the CASS components in the LBB piping systems for thermal aging embrittlement.
 
during the first or second outage following FSWOL application. The MRP-139 guidance for ISI goes beyond current ASME Code inspection requirements for PINGP Unit 2.
The NRC found that the inservice examination requirements in the May 7, 2008 letter, and Enclosure 2, Table 2 of Alternative Request 2-RR-4-8, Revision 1, were consistent
 
with, or more conservative than, the ASME Code, Section XI, Appendix Q. NSPM Responses to NRC Requests for Additional Information Dated November 20, 2008 4 RAI 4.7.1-5The applicant discusses Aging Management Program (AMP) B.2.1.41, Thermal Aging Embrittlement Of Cast Austenitic Stainless Steel (CASS), in Appendix B of the license renewal application. However, Section 4.7.1 does not mention this AMP for managing the LBB piping that is made of CASS. Discuss how CASS material of the LBB piping will be managed because AMP B.2.1.41 does not seem to be used to monitor the CASS components in the LBB piping systems for thermal aging embrittlement.
NSPM Response to RAI 4.7.1-5 As specified in PINGP LRA Table 3.1.2-2 (Page 3.1-60), the Thermal Aging Embrittlement of Cast Austenitic Stainless Steel (CASS) Program manages reduction of fracture toughness due to thermal aging embrittlement of CASS piping and fittings in the Reactor Coolant System (RCS). This is consistent with NUREG-1801, Line Item IV.C2-
NSPM Response to RAI 4.7.1-5 As specified in PINGP LRA Table 3.1.2-2 (Page 3.1-60), the Thermal Aging Embrittlement of Cast Austenitic Stainless Steel (CASS) Program manages reduction of fracture toughness due to thermal aging embrittlement of CASS piping and fittings in the Reactor Coolant System (RCS). This is consistent with NUREG-1801, Line Item IV.C2-
: 4. The Unit 1 and 2 RCS piping and fittings constructed of ASTM A351-CF8M material are included in the scope of AMP B2.1.39, Thermal Aging Embrittlement of Cast  
: 4. The Unit 1 and 2 RCS piping and fittings constructed of ASTM A351-CF8M material are included in the scope of AMP B2.1.39, Thermal Aging Embrittlement of Cast Austenitic Stainless Steel (CASS) Program.
 
RAI 4.7.1-6 By letter dated May 19, 2000, the NRC forwarded to the Nuclear Energy Institute an evaluation of thermal aging embrittlement of CASS components [ML003717179]. In the NRCs evaluation, the staff provided its positions on how to manage CASS components.
Austenitic Stainless Steel (CASS) Program.
Discuss how the CASS components in the LBB piping at both units satisfy the staff positions in its evaluation dated May 19, 2000.
RAI 4.7.1-6 By letter dated May 19, 2000, the NRC forwarded to the Nuclear Energy Institute an evaluation of thermal aging embrittlement of CASS components [ML003717179]. In the  
NSPM Response to RAI 4.7.1-6 The letter dated May 19, 2000, "License Renewal Issue No. 98-0030, Thermal Aging Embrittlement of Cast Austenitic Stainless Steel Components," provided the NRC staffs evaluation and proposed resolution of the subject issue. As presented in the letter, the staff provided its position for management, during the license renewal period, of thermal aging embrittlement in primary system components constructed of cast austenitic stainless steel (CASS). This position has since been incorporated as an aging management program described in NUREG-1801, Chapter XI, Program XI.M12, Thermal Aging Embrittlement of Cast Austenitic Stainless Steel (CASS). The program includes (a) determination of the susceptibility of CASS components to thermal aging embrittlement and (b) for potentially susceptible components, aging management is accomplished through either enhanced volumetric examination or plant- or component-specific flaw tolerance evaluation.
 
As shown in LRA Table 3.1.2-2, PINGP relies on the Thermal Aging Embrittlement of Cast Austenitic Stainless Steel (CASS) Program to manage the reduction of fracture toughness in CASS Reactor Coolant (RC) System piping and fittings. As described in LRA Section B2.1.39, the PINGP Thermal Aging Embrittlement of CASS Program is a 4
NRC's evaluation, the staff provided its positions on how to manage CASS components.
 
Discuss how the CASS components in the LBB piping at both units satisfy the staff  
 
positions in its evaluation dated May 19, 2000.
NSPM Response to RAI 4.7.1-6 The letter dated May 19, 2000, "License Renewal Issue No. 98-0030, Thermal Aging Embrittlement of Cast Austenitic Stainless Steel Components," provided the NRC staff's evaluation and proposed resolution of the subject issue. As presented in the letter, the staff provided its position for management, during the license renewal period, of thermal aging embrittlement in primary system components constructed of cast austenitic stainless steel (CASS). This position has since been incorporated as an aging management program described in NUREG-1801, Chapter XI, Program XI.M12, Thermal Aging Embrittlement of Cast Austenitic Stainless Steel (CASS). The program  
 
includes (a) determination of the susceptibility of CASS components to thermal aging  
 
embrittlement and (b) for potentially susceptible components, aging management is accomplished through either enhanced volumetric examination or plant- or component-specific flaw tolerance evaluation.
As shown in LRA Table 3.1.2-2, PINGP relies on the Thermal Aging Embrittlement of Cast Austenitic Stainless Steel (CASS) Program to manage the reduction of fracture toughness in CASS Reactor Coolant (RC) System piping and fittings. As described in  
 
LRA Section B2.1.39, the PINGP Thermal Aging Embrittlement of CASS Program is a   NSPM Responses to NRC Requests for Additional Information Dated November 20, 2008 5 new program that will be consistent with the recommendations of NUREG-1801, Chapter XI, Program XI.M12, Thermal Aging Embrittlement of Cast Austenitic Stainless
 
Steel (CASS).
The PINGP Thermal Aging Embrittlement of CASS Program scope includes the following CASS piping components which have been approved for Leak-Before-Break (LBB):Unit 1 large bore primary coolant piping fittings (elbows) which are constructed of
 
statically cast ASTM A351, Type CF8M material. Unit 2 large bore primary coolant piping (straight sections) which is constructed of
 
centrifugally cast ASTM A351, Type CF8M material. Unit 2 large bore primary coolant piping fittings (elbows) which are constructed of
 
statically cast ASTM A351, Type CF8M material.
The PINGP Thermal Aging Embrittlement of CASS Program includes a determination of the susceptibility of CASS components to thermal aging embrittlement based on casting method, molybdenum content, and percent ferrite. After applying the screening criteria
 
specified in the May 19, 2000 letter, Section 3.0 and NUREG-1801, XI.M12, Element 1, the following CASS components, in the scope of the program, were determined to be potentially susceptible to thermal aging embrittlement: A segment of straight RC System piping is potentially susceptible to thermal aging
 
embrittlement due to its high molybdenum content and ferrite content which
 
exceeds 20% by weight:
o Unit 2 RC System 27.5" I.D. cold leg piping in Loop A, Heat Number C-
 
1737The following RC System fittings are potentially susceptible to thermal aging
 
embrittlement due to their high molybdenum content and ferrite content which
 
exceeds 14% by weight:
o Unit 1 RC System 27.5" ID x 35D Elbow, Heat No. 33676 o Unit 1 RC System 31.0" ID x 90D Elbow w/ Splitter, Heat No. 13704 o Unit 1 RC System 31.0" ID x 90D Elbow w/ Splitter, Heat No. 19114 o Unit 2 RC System 27.5" ID x 35D Elbow, Heat No. 37758-2 o Unit 2 RC System 31.0" ID x 40D Elbow, Heat No. 38992-3 o Unit 2 RC System 31.0" ID x 90D Elbow, Heat No. 39231-2 For the CASS components determined to be potentially susceptible to thermal aging embrittlement, in accordance with criteria specified in the May 19, 2000 letter, Section
 
3.0, and in NUREG-1801, XI.M12, Elements 3 and 4, the program will provide enhanced volumetric examinations to detect and size cracks, or component-specific
 
flaw tolerance evaluations will be performed. The program will provide enhanced
 
volumetric examinations on the base metal determined to be limiting due to applied stress, operating time, and environmental considerations, using examination methods    NSPM Responses to NRC Requests for Additional Information Dated November 20, 2008 6that meet the criteria of ASME Section XI, Appendix VIII. Alternatively, component-specific flaw tolerance evaluations will be performed using specific geometry and


applied stress to demonstrate that the thermally-embrittled material has adequate
Enclosure 1 NSPM Responses to NRC Requests for Additional Information Dated November 20, 2008 new program that will be consistent with the recommendations of NUREG-1801, Chapter XI, Program XI.M12, Thermal Aging Embrittlement of Cast Austenitic Stainless Steel (CASS).
 
The PINGP Thermal Aging Embrittlement of CASS Program scope includes the following CASS piping components which have been approved for Leak-Before-Break (LBB):
toughness.Per NUREG-1801, XI.M12, Element 5, the PINGP Thermal Aging Embrittlement of Cast Austenitic Stainless Steel (CASS) Program will incorporate the inspection schedule of  
x  Unit 1 large bore primary coolant piping fittings (elbows) which are constructed of statically cast ASTM A351, Type CF8M material.
 
x  Unit 2 large bore primary coolant piping (straight sections) which is constructed of centrifugally cast ASTM A351, Type CF8M material.
IWB-2400 or IWC-2400 for potentially susceptible CASS components using ASME examination methods for the detection of cracking. Alternatively, component-specific flaw tolerance evaluations will be performed. Consistent with the criteria specified in the May 19, 2000 letter, Section 3.0, and in NUREG-1801, XI.M12, Element 6, flaws detected in CASS components will be evaluated in accordance with the applicable procedures of IWB-3500 or IWC-3500 in Section XI of the ASME Code. Alternatively, flaw tolerance evaluation for components with ferrite content up to 25% will be  
x  Unit 2 large bore primary coolant piping fittings (elbows) which are constructed of statically cast ASTM A351, Type CF8M material.
 
The PINGP Thermal Aging Embrittlement of CASS Program includes a determination of the susceptibility of CASS components to thermal aging embrittlement based on casting method, molybdenum content, and percent ferrite. After applying the screening criteria specified in the May 19, 2000 letter, Section 3.0 and NUREG-1801, XI.M12, Element 1, the following CASS components, in the scope of the program, were determined to be potentially susceptible to thermal aging embrittlement:
performed according to the principles associated with IWB-3640 procedures for
x  A segment of straight RC System piping is potentially susceptible to thermal aging embrittlement due to its high molybdenum content and ferrite content which exceeds 20% by weight:
 
o    Unit 2 RC System 27.5 I.D. cold leg piping in Loop A, Heat Number C-1737 x  The following RC System fittings are potentially susceptible to thermal aging embrittlement due to their high molybdenum content and ferrite content which exceeds 14% by weight:
submerged arc welds disregarding the Code restriction of 20% ferrite in IWB-3641(b)(1).
o    Unit 1 RC System 27.5 ID x 35D Elbow, Heat No. 33676 o    Unit 1 RC System 31.0 ID x 90D Elbow w/ Splitter, Heat No. 13704 o    Unit 1 RC System 31.0 ID x 90D Elbow w/ Splitter, Heat No. 19114 o    Unit 2 RC System 27.5 ID x 35D Elbow, Heat No. 37758-2 o    Unit 2 RC System 31.0 ID x 40D Elbow, Heat No. 38992-3 o    Unit 2 RC System 31.0 ID x 90D Elbow, Heat No. 39231-2 For the CASS components determined to be potentially susceptible to thermal aging embrittlement, in accordance with criteria specified in the May 19, 2000 letter, Section 3.0, and in NUREG-1801, XI.M12, Elements 3 and 4, the program will provide enhanced volumetric examinations to detect and size cracks, or component-specific flaw tolerance evaluations will be performed. The program will provide enhanced volumetric examinations on the base metal determined to be limiting due to applied stress, operating time, and environmental considerations, using examination methods 5


Enclosure 1 NSPM Responses to NRC Requests for Additional Information Dated November 20, 2008 that meet the criteria of ASME Section XI, Appendix VIII. Alternatively, component-specific flaw tolerance evaluations will be performed using specific geometry and applied stress to demonstrate that the thermally-embrittled material has adequate toughness.
Per NUREG-1801, XI.M12, Element 5, the PINGP Thermal Aging Embrittlement of Cast Austenitic Stainless Steel (CASS) Program will incorporate the inspection schedule of IWB-2400 or IWC-2400 for potentially susceptible CASS components using ASME examination methods for the detection of cracking. Alternatively, component-specific flaw tolerance evaluations will be performed. Consistent with the criteria specified in the May 19, 2000 letter, Section 3.0, and in NUREG-1801, XI.M12, Element 6, flaws detected in CASS components will be evaluated in accordance with the applicable procedures of IWB-3500 or IWC-3500 in Section XI of the ASME Code. Alternatively, flaw tolerance evaluation for components with ferrite content up to 25% will be performed according to the principles associated with IWB-3640 procedures for submerged arc welds disregarding the Code restriction of 20% ferrite in IWB-3641(b)(1).
PINGP does not have RC System CASS piping with >25% ferrite. Per NUREG-1801, XI.M12, Element 7, repair and replacement of CASS components will be performed in accordance with the requirements of ASME Section XI, Subsection IWA-4000.
PINGP does not have RC System CASS piping with >25% ferrite. Per NUREG-1801, XI.M12, Element 7, repair and replacement of CASS components will be performed in accordance with the requirements of ASME Section XI, Subsection IWA-4000.
RAI 4.7.1-7Explain whether the current fatigue crack growth analyses, as discussed in the fatigue crack growth section, are performed for 60 years. If not, discuss whether the current  
RAI 4.7.1-7 Explain whether the current fatigue crack growth analyses, as discussed in the fatigue crack growth section, are performed for 60 years. If not, discuss whether the current fatigue crack growth analyses, which are analyzed for 40 years, are applicable to 60 years. Provide the technical basis in detail.
 
NSPM Response to RAI 4.7.1-7 Large Primary Loop Pipe Rupture for PINGP Units 1 and 2 As reported in Section 6.0 of WCAP-10640-NP/WCAP-10639-P (for Unit 1) and WCAP-10928-NP/WCAP-10929-P (for Unit 2), the purpose of the fatigue crack growth analyses was to determine the sensitivity of the primary coolant system to the presence of small cracks. For the Unit 1 and Unit 2 large primary loop piping, a finite element stress analysis was completed for one of the highest-stressed cross sections of a plant typical in geometry and operational characteristics to any Westinghouse PWR system. Crack growths calculated in the selected region are representative of the entire primary loop.
fatigue crack growth analyses, which are analyzed for 40 years, are applicable to 60  
All normal, upset, and test conditions were considered, and circumferentially oriented surface flaws were postulated in the region, assuming the flaw was located in three different locations. Fatigue crack growth rate laws were used. The results of fatigue crack growth at 40 years for semi-elliptical surface flaws of circumferential orientation and various depths show that crack growth is very small at all three locations.
 
The TLAAs associated with the fatigue crack growth analyses are the normal, upset, and test conditions (i.e., NSSS design transients) that were used to calculate fatigue 6
years. Provide the technical basis in detail.
NSPM Response to RAI 4.7.1-7 Large Primary Loop Pipe Rupture for PINGP Units 1 and 2As reported in Section 6.0 of WCAP-10640-NP/WCAP-10639-P (for Unit 1) and WCAP-10928-NP/WCAP-10929-P (for Unit 2), the purpose of the fatigue crack growth analyses was to determine the sensitivity of the primary coolant system to the presence of small cracks. For the Unit 1 and Unit 2 large primary loop piping, a finite element stress analysis was completed for one of the highest-stressed cross sections of a plant typical  
 
in geometry and operational characteristics to any Westinghouse PWR system. Crack  
 
growths calculated in the selected region are representative of the entire primary loop.
All normal, upset, and test conditions were considered, and circumferentially oriented  
 
surface flaws were postulated in the region, assuming the flaw was located in three different locations. Fatigue crack growth rate laws were used. The results of fatigue  


crack growth at 40 years for semi-elliptical surface flaws of circumferential orientation and various depths show that crack growth is very small at all three locations. The TLAAs associated with the fatigue crack growth analyses are the normal, upset, and test conditions (i.e., NSSS design transients) that were used to calculate fatigue   NSPM Responses to NRC Requests for Additional Information Dated November 20, 2008 7 crack growth at 40 years. These design transients have not been changed or increased  
Enclosure 1 NSPM Responses to NRC Requests for Additional Information Dated November 20, 2008 crack growth at 40 years. These design transients have not been changed or increased for license renewal as discussed in Section 4.3 of the PINGP LRA. The existing numbers of thermal and loading cycles for each transient remain valid for 60 years of plant operation. Therefore, the fatigue crack growth calculations reported in WCAP-10640-NP/WCAP-10639-P (Unit 1) and WCAP-10928-NP/WCAP-10929-P (Unit 2) remain valid for the period of extended operation in accordance with 10 CFR 54.21(c)(1)(i).
Pressurizer Surge Line Rupture for PINGP Unit 1 As reported in Section 6.0 of WCAP-12876-NP/WCAP-12877-P, the purpose of the fatigue crack growth analyses for the PINGP Unit 1 pressurizer surge line was to determine the sensitivity of the pressurizer surge line to the presence of small cracks when subjected to the transients discussed in WCAP-12839, Structural Evaluation of Prairie Island Unit 1 Pressurizer Surge Line, Considering the Effects of Thermal Stratification.
For the Unit 1 pressurizer surge line, fatigue crack growth analyses were performed at two locations where detailed fracture mechanics evaluations were completed: (1) surge line piping near the reactor coolant hot leg nozzle, and (2) surge line piping near the pressurizer surge nozzle. Various initial semi-elliptical surface flaws with a six-to-one aspect ratio were assumed to exist. The largest initial flaw assumed was one with a depth equal to 10% of the nominal wall thickness. A fatigue crack growth law for austenitic stainless steel in a PWR environment was developed and used in the crack growth analyses. The results of fatigue crack growth at 40 years for an initial flaw of 10% nominal wall thickness show that crack growth is very small at both locations.
The TLAAs associated with the fatigue crack growth analyses are the normal, upset, and test conditions (i.e., NSSS design transients) and pressurizer surge line transient sub-events (to reflect stratification effects) presented in WCAP-12839 that were used to calculate fatigue crack growth at 40 years. The NSSS design transients and pressurizer surge line sub-events have not been changed or increased for license renewal as discussed in Section 4.3 of the PINGP LRA. The existing numbers of thermal and loading cycles for each transient remain valid for 60 years of plant operation. Therefore, the fatigue crack growth calculations reported in WCAP-12876-NP/WCAP-12877-P remain valid for the period of extended operation in accordance with 10 CFR 54.21(c)(1)(i).
For additional technical details associated with the PINGP Leak-Before-Break Analyses, please refer to the proprietary Westinghouse WCAP reports (i.e., those designated with
-P suffix above), which have been previously submitted to the NRC. See PINGP LRA, Section 4.0 References, References 15, 17, and 19 on Page 4.7-8.
7


for license renewal as discussed in Section 4.3 of the PINGP LRA. The existing numbers of thermal and loading cycles for each transient remain valid for 60 years of  
Enclosure 1 NSPM Responses to NRC Requests for Additional Information Dated November 20, 2008 RAI 4.7.1-8 Discuss whether the Unit 1 pressurizer surge line has experienced temperature transients in which temperature differences exceeded the design transients used in the LBB analyses. If out-of-limit transients occurred, describe how the LBB analyses for the Unit 1 surge line were re-evaluated to determine their acceptability.
NSPM Response to RAI 4.7.1-8 In accordance with Section 1.1 of WCAP-12876-NP/WCAP-12877-P, the results of the pressurizer surge line thermal stratification evaluation described in WCAP-12839 were used in the leak-before-break (LBB) analyses of the Unit 1 pressurizer surge line.
PINGP monitors thermal stratification in the pressurizer surge line by tracking the maximum temperature differential between the pressurizer water and the Reactor Coolant System (Loop B) hot leg during heatups and cooldowns to ensure compliance with the thermal stratification transients defined in WCAP-12839. There have been no instances in which temperature differences between the pressurizer and RCS have exceeded the design transients defined in WCAP-12839. In addition, the numbers of heatup and cooldown cycles experienced by the surge line are within the cycle limits specified in the analysis. Therefore, there have been no instances where the Unit 1 pressurizer surge line has experienced temperature transients that have exceeded the design transients used in the LBB analyses.
RAI 2.5 In the license renewal application, the applicant described the station blackout recovery paths for license renewal. As the licensee did not specifically exclude the associated control circuits and structures for the switchyard circuit breakers, it is assumed that these components are included in the scope of license renewal. In accordance with Title 10 of the Code of Federal Regulations (10 CFR) Section 54.4(a)(3) and License Renewal Sections 2.1.3.1.3 and 2.5.2.1.1 of the Standard Review Plan, the control circuits and structures associated with the circuit breaker should be in the scope of license renewal. Please confirm that these components are within the scope of license renewal.
NSPM Response to RAI 2.5 The station blackout recovery paths for license renewal purposes are described in the PINGP LRA. The control circuits and structures associated with the station blackout recovery path switchyard circuit breakers are in the scope of license renewal.
8


plant operation. Therefore, the fatigue crack growth calculations reported in WCAP-10640-NP/WCAP-10639-P (Unit 1) and WCAP-10928-NP/WCAP-10929-P (Unit 2) remain valid for the period of extended operation in accordance with 10 CFR 54.21(c)(1)(i).Pressurizer Surge Line Rupture for PINGP Unit 1As reported in Section 6.0 of WCAP-12876-NP/WCAP-12877-P, the purpose of the fatigue crack growth analyses for the PINGP Unit 1 pressurizer surge line was to determine the sensitivity of the pressurizer surge line to the presence of small cracks
Document Control Desk Page 2 Enclosure (1) cc:
Administrator, Region III, USNRC License Renewal Project Manager, Prairie Island, USNRC Resident Inspector, Prairie Island, USNRC Prairie Island Indian Community ATTN: Phil Mahowald Minnesota Department of Commerce


when subjected to the transients discussed in WCAP-12839, "Structural Evaluation of Prairie Island Unit 1 Pressurizer Surge Line, Considering the Effects of Thermal
Enclosure 1 NSPM Responses to NRC Requests for Additional Information Dated November 25, 2008 RAI 3.3.2.2.6-1 Prairie Island Nuclear Generating Plant (PINGP) Units 1 and 2 have Boraflex that is no longer credited for criticality in the spent fuel pools. There is no indication whether or not they still monitor the Boraflex for degradation. Past operating experience indicates that there can be blistering and bulging of the Boraflex material and the cladding surrounding the material. This can cause potential fuel handling safety issues.
 
Although Boraflex is not credited for criticality in the PINGP Unit 1 and 2 spent fuel pools, degradation of the material may impede safe handling of the spent fuel if blistering and/or bulging of the rack occurs. How will potential degradation of Boraflex material be identified and monitored during the proposed period of extended operation?
Stratification."For the Unit 1 pressurizer surge line, fatigue crack growth analyses were performed at two locations where detailed fracture mechanics evaluations were completed: (1) surge line piping near the reactor coolant hot leg nozzle, and (2) surge line piping near the pressurizer surge nozzle. Various initial semi-elliptical surface flaws with a six-to-one aspect ratio were assumed to exist. The largest initial flaw assumed was one with a
 
depth equal to 10% of the nominal wall thickness. A fatigue crack growth law for austenitic stainless steel in a PWR environment was developed and used in the crack growth analyses. The results of fatigue crack growth at 40 years for an initial flaw of 10% nominal wall thickness show that crack growth is very small at both locations.The TLAAs associated with the fatigue crack growth analyses are the normal, upset, and test conditions (i.e., NSSS design transients) and pressurizer surge line transient sub-events (to reflect stratification effects) presented in WCAP-12839 that were used to
 
calculate fatigue crack growth at 40 years. The NSSS design transients and pressurizer surge line sub-events have not been changed or increased for license renewal as discussed in Section 4.3 of the PINGP LRA. The existing numbers of thermal and loading cycles for each transient remain valid for 60 years of plant operation. Therefore, the fatigue crack growth calculations reported in WCAP-12876-NP/WCAP-12877-P
 
remain valid for the period of extended operation in accordance with 10 CFR
 
54.21(c)(1)(i).For additional technical details associated with the PINGP Leak-Before-Break Analyses, please refer to the proprietary Westinghouse WCAP reports (i.e., those designated with
"-P" suffix above), which have been previously submitted to the NRC. See PINGP LRA, "Section 4.0 References," References 15, 17, and 19 on Page 4.7-8. NSPM Responses to NRC Requests for Additional Information Dated November 20, 2008 8 RAI 4.7.1-8Discuss whether the Unit 1 pressurizer surge line has experienced temperature transients in which temperature differences exceeded the design transients used in the LBB analyses. If out-of-limit transients occurred, describe how the LBB analyses for the Unit 1 surge line were re-evaluated to determine their acceptability.
NSPM Response to RAI 4.7.1-8 In accordance with Section 1.1 of WCAP-12876-NP/WCAP-12877-P, the results of the pressurizer surge line thermal stratification evaluation described in WCAP-12839 were used in the leak-before-break (LBB) analyses of the Unit 1 pressurizer surge line. 
 
PINGP monitors thermal stratification in the pressurizer surge line by tracking the
 
maximum temperature differential between the pressurizer water and the Reactor Coolant System (Loop B) hot leg during heatups and cooldowns to ensure compliance with the thermal stratification transients defined in WCAP-12839. There have been no
 
instances in which temperature differences between the pressurizer and RCS have
 
exceeded the design transients defined in WCAP-12839. In addition, the numbers of heatup and cooldown cycles experienced by the surge line are within the cycle limits
 
specified in the analysis. Therefore, there have been no instances where the Unit 1 pressurizer surge line has experienced temperature transients that have exceeded the
 
design transients used in the LBB analyses.
RAI 2.5 In the license renewal application, the applicant described the station blackout recovery paths for license renewal. As the licensee did not specifically exclude the associated
 
control circuits and structures for the switchyard circuit breakers, it is assumed that these components are included in the scope of license renewal. In accordance with
 
Title 10 of the Code of Federal Regulations (10 CFR) Section 54.4(a)(3) and License Renewal Sections 2.1.3.1.3 and 2.5.2.1.1 of the Standard Review Plan, the control circuits and structures associated with the circuit breaker should be in the scope of license renewal. Please confirm that these components are within the scope of license
 
renewal.NSPM Response to RAI 2.5 The station blackout recovery paths for license renewal purposes are described in the PINGP LRA. The control circuits and structures associated with the station blackout recovery path switchyard circuit breakers are in the scope of license renewal. 
 
Document Control Desk Page 2 Enclosure (1) cc:  Administrator, Region III, USNRC License Renewal Project Manager, Prairie Island, USNRC Resident Inspector, Prairie Island, USNRC Prairie Island Indian Community ATTN:  Phil Mahowald  Minnesota Department of Commerce    NSPM Responses to NRC Requests for Additional Information Dated November 25, 2008 1 RAI 3.3.2.2.6-1 Prairie Island Nuclear Generating Plant (PINGP) Units 1 and 2 have Boraflex that is no longer credited for criticality in the spent fuel pools. There is no indication whether or not they still monitor the Boraflex for degradation. Past operating experience indicates that there can be blistering and bulging of the Boraflex material and the cladding  
 
surrounding the material. This can cause potential fuel handling safety issues.
Although Boraflex is not credited for criticality in the PINGP Unit 1 and 2 spent fuel pools, degradation of the material may impede safe handling of the spent fuel if blistering and/or bulging of the rack occurs. How will potential degradation of Boraflex  
 
material be identified and monitored during the proposed period of extended operation?
If degradation of Boraflex is identified, what mitigation strategies will be employed?
If degradation of Boraflex is identified, what mitigation strategies will be employed?
NSPM Response to RAI 3.3.2.2.6-1The spent fuel storage racks are described in the PINGP USAR, Section 10.2.1.Criticality is prevented by the design of the racks which limits fuel assembly interaction by fixing the minimum separation between assemblies, and by maintaining soluble neutron poison in the spent fuel pool water. No mitigative strategy is required for monitoring the spent fuel pool Boraflex material used in the design of spent fuel storage rack fuel module assemblies. The design of the PINGP spent fuel storage rack fuel module assemblies allows for the release of gasses created by the degrading Boraflex material without degrading the surrounding stainless steel material. The spent fuel storage rack fuel module assembly design at PINGP incorporates Boraflex which differs from the design that incorporates Boral&#x17d;. Boraflex is a material composed of 46% silica, 4% polydimethyl, and 50% boron carbide. The fuel module assemblies consist of an inner stainless steel casing, a layer of Boraflex neutron  
NSPM Response to RAI 3.3.2.2.6-1 The spent fuel storage racks are described in the PINGP USAR, Section 10.2.1.
 
Criticality is prevented by the design of the racks which limits fuel assembly interaction by fixing the minimum separation between assemblies, and by maintaining soluble neutron poison in the spent fuel pool water. No mitigative strategy is required for monitoring the spent fuel pool Boraflex material used in the design of spent fuel storage rack fuel module assemblies. The design of the PINGP spent fuel storage rack fuel module assemblies allows for the release of gasses created by the degrading Boraflex material without degrading the surrounding stainless steel material.
absorbing material, and an outer stainless steel casing (see sketch below). The inner  
The spent fuel storage rack fuel module assembly design at PINGP incorporates Boraflex which differs from the design that incorporates Boral'. Boraflex is a material composed of 46% silica, 4% polydimethyl, and 50% boron carbide. The fuel module assemblies consist of an inner stainless steel casing, a layer of Boraflex neutron absorbing material, and an outer stainless steel casing (see sketch below). The inner and outer square stainless steel casings are tubular. The outer casing holds the Boraflex in place and is only one-quarter the thickness of the inner casing. The outer casing is attached to the inner casing by four spot welds at the top and bottom of the outer casing on each of the four sides. Thus, the outer casing is not leak tight. This vented cavity design allows the release of gasses and ingress of water to alleviate the potential for cell wall bulging as a result of the Boraflex material off gassing.
 
Industry OE indicates that Boraflex degrades over time, but the degradation process does not impede the ability to remove or accept fuel since the fuel module assemblys open flow design allows gasses to vent safely to the spent fuel pool water. Bulging, blistering, or other deformation, known to occur in poorly vented designs, is not applicable at PINGP.
and outer square stainless steel casings are tubular. The outer casing holds the Boraflex in place and is only one-quarter the thickness of the inner casing. The outer casing is attached to the inner casing by four spot welds at the top and bottom of the  
1
 
outer casing on each of the four sides. Thus, the outer casing is not leak tight. This  
 
vented cavity design allows the release of gasses and ingress of water to alleviate the  
 
potential for cell wall bulging as a result of the Boraflex material off gassing. Industry OE indicates that Boraflex degrades over time, but the degradation process does not impede the ability to remove or accept fuel since the fuel module assembly's open flow design allows gasses to vent safely to the spent fuel pool water. Bulging, blistering, or other deformation, known to occur in poorly vented designs, is not  
 
applicable at PINGP. NSPM Responses to NRC Requests for Additional Information Dated November 25, 2008 2Sketch of Spent Fuel Rack Fuel Module Assembly Although not in use at PINGP, Boral&#x17d; is another neutron absorber material used in the design of spent fuel storage rack fuel module assemblies. It is technically a cermet, and is classified as a metal matrix neutron absorber manufactured by hot rolling a cubic
 
aluminum ingot containing powdered aluminum and boron carbide to a final gage.
Sheets of Boral&#x17d; are encapsulated between aluminum sheets to form storage tubes.
Industry operating experience indicates that this design was not properly vented
 
resulting in gas pressure buildup between the sheets causing blistering, deformation and/or swelling of the module assemblies. This experience with Boral&#x17d; is not
 
applicable to the Boraflex used at PINGP. NSPM Responses to NRC Requests for Additional Information Dated November 25, 2008 3 RAI 2.1.1.4.3-1 NUREG 1801, "Generic Aging Lessons Learned  Report," Volume 2, Revision 1, (GALL)
AMP XI.S8, Protective Coating Monitoring and Maintenance Program, is not credited for aging management in the licensee's application. In the application it states that "PINGP does not credit coatings inside containment to assure that the intended functions of coated structures and components are maintained." However, in addition to using the Protective Coating Monitoring and Maintenance Program to ensure the function of coated structures and components, the GALL Report states that "Proper maintenance of protective coatings inside containment is essential to ensure operability of post-accident safety systems that rely on water recycled through the containment sump/drain system." Although the applicant does not credit the program for aging management, there needs to be adequate assurance that there is proper maintenance of the protective coatings in containment, such that they will not degrade and become a debris
 
source that may challenge the Emergency Core Cooling Systems performance.
Therefore the staff requires the following additional information: Please describe in detail the coatings assessment program referenced in the supplemental response to Generic Letter 2004-02 (dated February 28, 2008). How will the program ensure that there will be proper maintenance of the protective coatings
 
inside containment and ensure operability of post-accident safety systems that rely on water recycled through the containment sump/drain system in the extended period of
 
operation? Also, describe the frequency and scope of the inspections, acceptance
 
criteria, and the qualification of personnel who perform containment coatings inspections.
NSPM Response to RAI 2.1.1.4.3-1The coatings assessment program at PINGP, described in the supplemental response to GL 2004-02, "Potential Impact of Debris Blockage on Emergency Recirculation during DBA at Pressurized-Water Reactors" (dated 2-28-08), ensures proper maintenance of
 
coatings through implemented activities that perform inspections and assessment of the condition of coatings inside containment to confirm that the volume of debris that could
 
block the sump recirculation strainers remains conservatively low.
Plant procedures provide the means to check the condition of coatings as a potential source of debris that could block the sump recirculation strainers. These procedures provide requirements for personnel qualification, inspection procedures, criteria for recording degradation, acceptance criteria, and tracking of unqualified coatings and degraded coatings. Containment coatings are subject to ongoing oversight that ensure compliance with the current licensing basis. These activities, however, do not prevent
 
coating failures, and are used only to minimize debris that could be generated during a
 
LOCA.In accordance with the PINGP coating assessment program, a visual inspection for degraded qualified coatings inside the Containment Building is performed every outage.
 
Degraded qualified coating is a previously qualified coating that exhibits any defects    NSPM Responses to NRC Requests for Additional Information Dated November 25, 2008 4such as blistering, cracking, flaking, peeling, delaminating or rusting. An inspection for unqualified coatings, to verify compliance with the design basis for the sump screen, is


performed every other outage, and was completed for both Units in 2008. An
Enclosure 1 NSPM Responses to NRC Requests for Additional Information Dated November 25, 2008 Sketch of Spent Fuel Rack Fuel Module Assembly Although not in use at PINGP, Boral' is another neutron absorber material used in the design of spent fuel storage rack fuel module assemblies. It is technically a cermet, and is classified as a metal matrix neutron absorber manufactured by hot rolling a cubic aluminum ingot containing powdered aluminum and boron carbide to a final gage.
Sheets of Boral' are encapsulated between aluminum sheets to form storage tubes.
Industry operating experience indicates that this design was not properly vented resulting in gas pressure buildup between the sheets causing blistering, deformation and/or swelling of the module assemblies. This experience with Boral' is not applicable to the Boraflex used at PINGP.
2


unqualified coating is a coating that cannot be attested to having passed the required
Enclosure 1 NSPM Responses to NRC Requests for Additional Information Dated November 25, 2008 RAI 2.1.1.4.3-1 NUREG 1801, Generic Aging Lessons Learned Report, Volume 2, Revision 1, (GALL)
AMP XI.S8, Protective Coating Monitoring and Maintenance Program, is not credited for aging management in the licensees application. In the application it states that PINGP does not credit coatings inside containment to assure that the intended functions of coated structures and components are maintained. However, in addition to using the Protective Coating Monitoring and Maintenance Program to ensure the function of coated structures and components, the GALL Report states that Proper maintenance of protective coatings inside containment is essential to ensure operability of post-accident safety systems that rely on water recycled through the containment sump/drain system. Although the applicant does not credit the program for aging management, there needs to be adequate assurance that there is proper maintenance of the protective coatings in containment, such that they will not degrade and become a debris source that may challenge the Emergency Core Cooling Systems performance.
Therefore the staff requires the following additional information:
Please describe in detail the coatings assessment program referenced in the supplemental response to Generic Letter 2004-02 (dated February 28, 2008). How will the program ensure that there will be proper maintenance of the protective coatings inside containment and ensure operability of post-accident safety systems that rely on water recycled through the containment sump/drain system in the extended period of operation? Also, describe the frequency and scope of the inspections, acceptance criteria, and the qualification of personnel who perform containment coatings inspections.
NSPM Response to RAI 2.1.1.4.3-1 The coatings assessment program at PINGP, described in the supplemental response to GL 2004-02, "Potential Impact of Debris Blockage on Emergency Recirculation during DBA at Pressurized-Water Reactors" (dated 2-28-08), ensures proper maintenance of coatings through implemented activities that perform inspections and assessment of the condition of coatings inside containment to confirm that the volume of debris that could block the sump recirculation strainers remains conservatively low.
Plant procedures provide the means to check the condition of coatings as a potential source of debris that could block the sump recirculation strainers. These procedures provide requirements for personnel qualification, inspection procedures, criteria for recording degradation, acceptance criteria, and tracking of unqualified coatings and degraded coatings. Containment coatings are subject to ongoing oversight that ensure compliance with the current licensing basis. These activities, however, do not prevent coating failures, and are used only to minimize debris that could be generated during a LOCA.
In accordance with the PINGP coating assessment program, a visual inspection for degraded qualified coatings inside the Containment Building is performed every outage.
Degraded qualified coating is a previously qualified coating that exhibits any defects 3


laboratory testing, including irradiation and simulated Design Basis Accident (DBA), or has inadequate quality documentation to support its use as being DBA qualified.Unqualified coating is found on equipment such as motor control centers, control valves, unistrut, cabinets, etc., and is applied by the original equipment manufacturer.The scope of coatings inspections include interior accessible coated surfaces of the Reactor Containment Vessels, Unit 1 and Unit 2, and the equipment permanently  
Enclosure 1 NSPM Responses to NRC Requests for Additional Information Dated November 25, 2008 such as blistering, cracking, flaking, peeling, delaminating or rusting. An inspection for unqualified coatings, to verify compliance with the design basis for the sump screen, is performed every other outage, and was completed for both Units in 2008. An unqualified coating is a coating that cannot be attested to having passed the required laboratory testing, including irradiation and simulated Design Basis Accident (DBA), or has inadequate quality documentation to support its use as being DBA qualified.
Unqualified coating is found on equipment such as motor control centers, control valves, unistrut, cabinets, etc., and is applied by the original equipment manufacturer.
The scope of coatings inspections include interior accessible coated surfaces of the Reactor Containment Vessels, Unit 1 and Unit 2, and the equipment permanently contained therein.
Acceptance criteria for coatings are based on industry guidance in ASTM D714-04, Standard Method for Evaluating Degree of Blistering of Paints and ASTM D610-01, Standard Method for Evaluating Degree of Rusting of Painted Steel Surfaces.
Evidence of a degraded condition includes blistering, cracking, flaking, peeling, delaminating, rusting and discoloration. Any degraded condition is documented and measurements are taken to clearly characterize the degradation. When the condition of the coating is in question, a destructive test can be performed to more accurately assess the condition of the coating. Destructive test methods include ASTM D4541, Test Method for Pull-Off Strength of Coatings Using Portable Adhesion Testers, or D6677, Standard Test Method for Evaluation by Knife. Any identified degradation is dispositioned in accordance with the Corrective Action Process.
The method of performing the coatings inspection, including the degradation recording criteria, is based on ASTM D5163, Standard Guide for Establishing Procedures to Monitor the Performance of Coating Service Level 1 Coating Systems in an Operating Nuclear Power Plant."
Qualification of personnel who perform the containment coatings inspections is in accordance with ANSI N45.2.6 as defined in the PINGP coating assessment program.
4


contained therein.Acceptance criteria for coatings are based on industry guidance in ASTM D714-04, "Standard Method for Evaluating Degree of Blistering of Paints" and ASTM D610-01, "Standard Method for Evaluating Degree of Rusting of Painted Steel Surfaces."
Enclosure (1) cc:
Evidence of a degraded condition includes blistering, cracking, flaking, peeling, delaminating, rusting and discoloration. Any degraded condition is documented and measurements are taken to clearly characterize the degradation. When the condition of the coating is in question, a destructive test can be performed to more accurately assess the condition of the coating. Destructive test methods include ASTM D4541, "Test Method for Pull-Off Strength of Coatings Using Portable Adhesion Testers," or D6677, "Standard Test Method for Evaluation by Knife."  Any identified degradation is dispositioned in accordance with the Corrective Action Process.The method of performing the coatings inspection, including the degradation recording criteria, is based on ASTM D5163, "Standard Guide for Establishing Procedures to
Administrator, Region III, USNRC License Renewal Project Manager, Prairie Island, USNRC Resident Inspector, Prairie Island, USNRC Prairie Island Indian Community ATTN: Phil Mahowald Minnesota Department of Commerce


Monitor the Performance of Coating Service Level 1 Coating Systems in an Operating
Enclosure 1 NSPM Responses to NRC Requests for Additional Information Dated December 1, 2008 RAI 2.4.1-1 Due to lack of clarity in the license renewal application (LRA) Tables 2.4.1-1 and 3.5.2-1, please confirm/clarify if the Spent Fuel Pool (SFP) Divider Gates, the SFP leak-chase channels, and the fuel transfer canal upending frame are structural components in the scope of license renewal and subject to an aging management review (AMR). If yes, include their scoping, screening and AMR results, as appropriate, or clarify the location in the LRA where these components are included. If not, please provide justification for exclusion.
 
NSPM Response to RAI 2.4.1-1 Spent Fuel Pool (SFP) Divider Gates are not in scope of license renewal since they perform no intended function. As discussed in USAR Section 10.2.2.3, to protect against complete loss of water in the spent fuel pool, spent fuel pool cooling system piping connections enter the top of the pool. The drain connection from the transfer canal to the CVSC holdup tank recirculation pump is at the canals bottom. Even if the water in the transfer canal were completely drained with the SFP gate removed, the active portion of the spent fuel would not be uncovered. This is because the bottom of the gate connection in the wall separating the transfer canal from the spent fuel pool is at an elevation that would preclude complete drainage.
Nuclear Power Plant." Qualification of personnel who perform the containment coatings inspections is in accordance with ANSI N45.2.6 as defined in the PINGP coating assessment program.
SFP leak-chase channels are in scope of license renewal. There components are located in the Auxiliary Building, are fabricated from stainless steel, and are located in an embedded-in-concrete environment. See LRA Table 2.4.1-1 on page 2.4-9 (i.e.,
 
stainless steel components), and Table 3.5.2-1 on page 3.5-77 (i.e., stainless steel components (embedded members)).
Enclosure (1) cc:  Administrator, Region III, USNRC License Renewal Project Manager, Prairie Island, USNRC Resident Inspector, Prairie Island, USNRC Prairie Island Indian Community ATTN:  Phil Mahowald  Minnesota Department of Commerce    NSPM Responses to NRC Requests for Additional Information Dated December 1, 2008 1 RAI 2.4.1-1 Due to lack of clarity in the license renewal application (LRA) Tables 2.4.1-1 and 3.5.2-1, please confirm/clarify if the Spent Fuel Pool (SFP) Divider Gates, the SFP leak-chase channels, and the fuel transfer canal upending frame are structural components in the scope of license renewal and subject to an aging management review (AMR). If yes, include their scoping, screening and AMR results, as appropriate, or clarify the location in the LRA where these components are included. If not, please provide justification for exclusion.
The fuel transfer canal upender (or tipping device) is in scope of license renewal. The upending frame is part of the fuel transfer tipping device identified in the LRA Section 2.4.3, page 2.4-18. See LRA Table 3.5.2-3 on pages 3.5-115 and 3.5-116 for aging management of the fuel transfer tipping devices.
NSPM Response to RAI 2.4.1-1Spent Fuel Pool (SFP) Divider Gates are not in scope of license renewal since they perform no intended function. As discussed in USAR Section 10.2.2.3, to protect against complete loss of water in the spent fuel pool, spent fuel pool cooling system  
RAI 2.4.3-1 In Updated Final Safety Analysis Report (UFSAR) Section 12.2.6, the applicant states that in order to assure the stability and prevent toppling and over-traveling of the containment polar crane or its components, the features incorporated in its design include: (i) up-kick lugs fastened to each truck; (ii) overturning locks fastened to each truck; and (iii) positive wheel stops. Also, in UFSAR Section 12.2.9, the applicant indicates that the spent fuel pool bridge crane, auxiliary building crane and the turbine building crane are protected against tipping, derailments and uncontrolled movements by features that include: (i) crane bridge and trolley being equipped with fixed, fitted rail yokes; and (ii) positive wheel stops and bumpers. From LRA Section 2.4.3, Table 2.4.3-1 and Table 3.5.2-3, it is not clear if the above noted structural components and fasteners of the cranes are included in-scope of license renewal and subject to an AMR.
 
1
piping connections enter the top of the pool. The drain connection from the transfer canal to the CVSC holdup tank recirculation pump is at the canal's bottom. Even if the water in the transfer canal were completely drained with the SFP gate removed, the active portion of the spent fuel would not be uncovered. This is because the bottom of the gate connection in the wall separating the transfer canal from the spent fuel pool is  
 
at an elevation that would preclude complete drainage. SFP leak-chase channels are in scope of license renewal. There components are located in the Auxiliary Building, are fabricated from stainless steel, and are located in  
 
an embedded-in-concrete environment. See LRA Table 2.4.1-1 on page 2.4-9 (i.e.,
stainless steel components), and Table 3.5.2-1 on page 3.5-77 (i.e., stainless steel components (embedded members)). The fuel transfer canal upender (or tipping device) is in scope of license renewal. The upending frame is part of the fuel transfer tipping device identified in the LRA Section  
 
2.4.3, page 2.4-18. See LRA Table 3.5.2-3 on pages 3.5-115 and 3.5-116 for aging  
 
management of the fuel transfer tipping devices.
RAI 2.4.3-1 In Updated Final Safety Analysis Report (UFSAR) Section 12.2.6, the applicant states that in order to assure the stability and prevent toppling and over-traveling of the  
 
containment polar crane or its components, the features incorporated in its design include: (i) up-kick lugs fastened to each truck; (ii) overturning locks fastened to each truck; and (iii) positive wheel stops. Also, in UFSAR Section 12.2.9, the applicant indicates that the spent fuel pool bridge crane, auxiliary building crane and the turbine building crane are protected against tipping, derailments and uncontrolled movements by features that include: (i) crane bridge and trolley being equipped with fixed, fitted rail yokes; and (ii) positive wheel stops and bumpers. From LRA Section 2.4.3, Table 2.4.3-1 and Table 3.5.2-3, it is not clear if the above noted structural components and fasteners of the cranes are included in-scope of license renewal and subject to an AMR. NSPM Responses to NRC Requests for Additional Information Dated December 1, 2008 2 Please confirm if these crane components have been screened in as items requiring an AMR. If yes, indicate where these items have been included in the LRA. If not, provide
 
the technical bases for their exclusion.
NSPM Response to RAI 2.4.3-1Structural components and fasteners for the containment polar crane (up-kick lugs, overturning locks, positive wheel stops), spent fuel pool bridge crane, auxiliary building
 
crane, and the turbine building crane (fixed, fitted rail yokes, and positive wheel stops
 
and bumpers) identified in Sections 12.2.6 and 12.2.9 of the USAR, are in-scope of License Renewal and subject to an AMR. They are included in the LRA description in
 
Section 2.4.3 which characterized them as miscellaneous load carrying components, and in Table 2.4.3-1 under the component heading, "Cranes - Rails" and "Cranes -
Structural Girders."  These components are further defined in Table 3.5.2-3 as "Cranes -
structural girders (load carrying structural members, welded and bolted connections
 
....)," and "Cranes -rails (rails and associated welded and bolted connections ....)."


Enclosure 1 NSPM Responses to NRC Requests for Additional Information Dated December 1, 2008 Please confirm if these crane components have been screened in as items requiring an AMR. If yes, indicate where these items have been included in the LRA. If not, provide the technical bases for their exclusion.
NSPM Response to RAI 2.4.3-1 Structural components and fasteners for the containment polar crane (up-kick lugs, overturning locks, positive wheel stops), spent fuel pool bridge crane, auxiliary building crane, and the turbine building crane (fixed, fitted rail yokes, and positive wheel stops and bumpers) identified in Sections 12.2.6 and 12.2.9 of the USAR, are in-scope of License Renewal and subject to an AMR. They are included in the LRA description in Section 2.4.3 which characterized them as miscellaneous load carrying components, and in Table 2.4.3-1 under the component heading, Cranes - Rails and Cranes -
Structural Girders. These components are further defined in Table 3.5.2-3 as Cranes -
structural girders (load carrying structural members, welded and bolted connections
....), and Cranes -rails (rails and associated welded and bolted connections ....).
Bumpers are considered subcomponents of the crane structural assembly and are not explicitly called out.
Bumpers are considered subcomponents of the crane structural assembly and are not explicitly called out.
RAI 2.4.7-1 In LRA Section 2.4.7, the system function listing under code RCV-04, "Reactor Containment Vessels and their internal structures provide shielding against high energy line breaks," indicates scoping under 10 CFR 54.4(a)(2), which corresponds to all non-safety related systems, structures and components, whose failure could prevent satisfactory accomplishment of any of the functions identified in 10 CFR 54.4(a)(1). The  
RAI 2.4.7-1 In LRA Section 2.4.7, the system function listing under code RCV-04, Reactor Containment Vessels and their internal structures provide shielding against high energy line breaks, indicates scoping under 10 CFR 54.4(a)(2), which corresponds to all non-safety related systems, structures and components, whose failure could prevent satisfactory accomplishment of any of the functions identified in 10 CFR 54.4(a)(1). The comment under this item on LRA page 2.4-38 states that: Reactor Containment Vessels and their internal structures are designed to withstand the effects of high energy line breaks without loss of function. Reinforced concrete walls and steel structures inside each Reactor Containment Vessel shield safety related equipment from the effects of a HELB. The NRC staff finds that the above stated structures and structural components are generally safety-related and are in scope in accordance with 10 CFR 54.4(a)(1). Please address the inconsistency.
NSPM Response to RAI 2.4.7-1 Criterion 10 CFR 54.4(a)(2), as it applies to Code RCV-04 on page 2.4-38 of the LRA, is used to describe the HELB protection function applicable to certain non-safety related concrete and steel structures inside each Reactor Containment Vessel including whip restraints and jet impingement shields whose only function is to provide HELB protection for safety related equipment. NEI 95-10, Appendix F, Section 3.4 states that:
NSR whip restraints, jet impingement shields, blowout panels, etc., that are designed and installed to protect SR equipment from the effects of a HELB, are within the scope of license renewal per 10 CFR 54.4(a)(2).
2


comment under this item on LRA page 2.4-38 states that: "Reactor Containment
Enclosure 1 NSPM Responses to NRC Requests for Additional Information Dated December 1, 2008 There are also concrete and steel structures inside the reactor containment vessels that perform a HELB function in combination with safety related functions such as missile protection and structural support to safety related components. In an attempt to avoid confusion, the HELB system function was only used to identify non-safety related structures whose only function is to provide HELB protection for safety related equipment. LRA Table 3.5.2-7 provides a list of safety related concrete and steel structures with multiple functions, one of which is HELB protection.
 
Vessels and their internal structures are designed to withstand the effects of high energy line breaks without loss of function. Reinforced concrete walls and steel structures inside each Reactor Containment Vessel shield safety related equipment from the effects of a HELB."  The NRC staff finds that the above stated structures and structural components are generally safety-related and are in scope in accordance with 10 CFR 54.4(a)(1). Please address the inconsistency.
NSPM Response to RAI 2.4.7-1Criterion 10 CFR 54.4(a)(2), as it applies to Code RCV-04 on page 2.4-38 of the LRA, is used to describe the HELB protection function applicable to certain non-safety related
 
concrete and steel structures inside each Reactor Containment Vessel including whip restraints and jet impingement shields whose only function is to provide HELB protection for safety related equipment. NEI 95-10, Appendix F, Section 3.4 states that: "NSR whip restraints, jet impingement shields, blowout panels, etc., that are designed and installed to protect SR equipment from the effects of a HELB, are within the scope
 
of license renewal per 10 CFR 54.4(a)(2)."  NSPM Responses to NRC Requests for Additional Information Dated December 1, 2008 3 There are also concrete and steel structures inside the reactor containment vessels that perform a HELB function in combination with safety related functions such as missile protection and structural support to safety related components. In an attempt to avoid confusion, the HELB system function was only used to identify non-safety related structures whose only function is to provide HELB protection for safety related equipment. LRA Table 3.5.2-7 provides a list of safety related concrete and steel structures with multiple functions, one of which is HELB protection.
RAI 2.4.7-2 Because of lack of clarity in LRA Tables 2.4.2-1, 2.4.7-1, 3.5.2-2, 3.5.2-7 and the corresponding LRA sections, please indicate where in the LRA are the scoping, screening and AMR results of structural supports (vertical and lateral, as appropriate) for steam generators, reactor coolant pumps and the reactor vessel included. If these structural components were inadvertently not included, please provide their scoping, screening and AMR results, otherwise justify the exclusion.
RAI 2.4.7-2 Because of lack of clarity in LRA Tables 2.4.2-1, 2.4.7-1, 3.5.2-2, 3.5.2-7 and the corresponding LRA sections, please indicate where in the LRA are the scoping, screening and AMR results of structural supports (vertical and lateral, as appropriate) for steam generators, reactor coolant pumps and the reactor vessel included. If these structural components were inadvertently not included, please provide their scoping, screening and AMR results, otherwise justify the exclusion.
NSPM Response to RAI 2.4.7-2Supports for the reactor vessels, steam generators, and reactor coolant pumps are identified in the PINGP USAR, Section 12.2.4 and Table 12.2-1, as Class 1 structures consistent with Chapter III.B1.1 of NUREG-1801. LRA Table 3.5.2-2 refers to them by  
NSPM Response to RAI 2.4.7-2 Supports for the reactor vessels, steam generators, and reactor coolant pumps are identified in the PINGP USAR, Section 12.2.4 and Table 12.2-1, as Class 1 structures consistent with Chapter III.B1.1 of NUREG-1801. LRA Table 3.5.2-2 refers to them by the component type, Support (... Class 1 vessels, exchangers, and pumps ...). Only the Unit 2 steam generator supports and the Units 1 and 2 reactor coolant pump supports are installed using high strength bolts, and therefore Table 3.5.2-2 specifically identifies these supports for this application.
 
LRA Section 2.4.2 includes a list of in-scope component supports which includes pressure vessels, heat exchangers, and pumps, and LRA Table 2.4.2-1 combines all in-scope supports under the component heading, Support.
the component type, "Support (... Class 1 vessels, exchangers, and pumps ...).Only the Unit 2 steam generator supports and the Units 1 and 2 reactor coolant pump supports are installed using high strength bolts, and therefore Table 3.5.2-2 specifically identifies these supports for this application.
RAI 2.4.8-1 Please confirm if there are any ductbanks and manholes in the yard that are safety-related or important-to-safety or required for regulated events that may be within the scope of license renewal and subject to an AMR. If there are, please provide their scoping, screening and AMR results.
LRA Section 2.4.2 includes a list of in-scope component supports which includes pressure vessels, heat exchangers, and pumps, and LRA Table 2.4.2-1 combines all in-
NSPM Response to RAI 2.4.8-1 There are no ductbanks in scope of license renewal, and only one manhole is in scope and subject to an AMR. The single manhole, in scope for the SBO regulated event, is located about 100 feet west of the Security Building. It provides access to splices in the 13.8 kV cables that run from the switchyard to the Cooling Tower Equipment House.
 
License Renewal Boundary drawing LR-193817, entitled, PINGP Site Layout of the 3
scope supports under the component heading, "Support."
RAI 2.4.8-1 Please confirm if there are any ductbanks and manholes in the yard that are safety-related or important-to-safety or required for regulated events that may be within the scope of license renewal and subject to an AMR. If there are, please provide their  
 
scoping, screening and AMR results.
NSPM Response to RAI 2.4.8-1 There are no ductbanks in scope of license renewal, and only one manhole is in scope and subject to an AMR. The single manhole, in scope for the SBO regulated event, is  
 
located about 100 feet west of the Security Building. It provides access to splices in the 13.8 kV cables that run from the switchyard to the Cooling Tower Equipment House.
License Renewal Boundary drawing LR-193817, entitled, "PINGP Site Layout of the   NSPM Responses to NRC Requests for Additional Information Dated December 1, 2008 4Owner Controlled Area," provides its location (Item 57, coordinate D6). LRA Section 2.4.8 provides a description of the manhole structure, and Table 2.4.8-1 identified its components as "Concrete" and "Steel Components."  Table 3.5.2-8 further defines the concrete portion of the structure as "Concrete (... cable vault...)," and its metal components as "Steel components (... miscellaneous structures/equipment items ...)."The aging effects for the manhole structure are managed by the Structures Monitoring Program based on the results of the AMR.
RAI 2.4.11-1 Section 1.3.2 of the UFSAR states that the plant screenhouse houses the cooling water pumps, fire pumps, circulating water pumps, trash racks and traveling screens. Due to
 
lack of clarity in LRA Tables 2.4.11-1 and 3.5.2-11, please confirm the inclusion or exclusion of the trash racks and traveling screens as structural components within the scope of license renewal and subject to an AMR. If they were not included as an oversight, please provide a description of their scoping and AMR. If they are included
 
elsewhere in the LRA, please indicate the location. If they are excluded from the scope
 
of license renewal and AMR, please provide the basis for their exclusion.
NSPM Response to RAI 2.4.11-1 The trash racks and traveling screen support components are in scope of License Renewal, and the aging effects are managed by the RG 1.127, Inspection of Water-
 
Control Structures Associated with Nuclear Power Plants Program. See LRA Table 2.4.11-1 which identifies the components as "Steel Components" and see Table 3.5.2-11 which further defines the components as "Steel components (Screenhouse trash racks, safeguards traveling screen frames, safeguards bay gates, fasteners ...)."  The
 
traveling screen portion of the screen assembly is active and therefore, does not require


an AMR.}}
Enclosure 1 NSPM Responses to NRC Requests for Additional Information Dated December 1, 2008 Owner Controlled Area, provides its location (Item 57, coordinate D6). LRA Section 2.4.8 provides a description of the manhole structure, and Table 2.4.8-1 identified its components as Concrete and Steel Components. Table 3.5.2-8 further defines the concrete portion of the structure as Concrete (... cable vault...), and its metal components as Steel components (... miscellaneous structures/equipment items ...).
The aging effects for the manhole structure are managed by the Structures Monitoring Program based on the results of the AMR.
RAI 2.4.11-1 Section 1.3.2 of the UFSAR states that the plant screenhouse houses the cooling water pumps, fire pumps, circulating water pumps, trash racks and traveling screens. Due to lack of clarity in LRA Tables 2.4.11-1 and 3.5.2-11, please confirm the inclusion or exclusion of the trash racks and traveling screens as structural components within the scope of license renewal and subject to an AMR. If they were not included as an oversight, please provide a description of their scoping and AMR. If they are included elsewhere in the LRA, please indicate the location. If they are excluded from the scope of license renewal and AMR, please provide the basis for their exclusion.
NSPM Response to RAI 2.4.11-1 The trash racks and traveling screen support components are in scope of License Renewal, and the aging effects are managed by the RG 1.127, Inspection of Water-Control Structures Associated with Nuclear Power Plants Program. See LRA Table 2.4.11-1 which identifies the components as Steel Components and see Table 3.5.2-11 which further defines the components as Steel components (Screenhouse trash racks, safeguards traveling screen frames, safeguards bay gates, fasteners ...). The traveling screen portion of the screen assembly is active and therefore, does not require an AMR.
4}}

Latest revision as of 10:27, 14 November 2019

2008/12/11 PINGP Lr - Four PINGP License Renewal RAI Response Letters
ML083500121
Person / Time
Site: Prairie Island  Xcel Energy icon.png
Issue date: 12/11/2008
From:
- No Known Affiliation
To:
Division of License Renewal
References
Download: ML083500121 (33)


Text

PrairieIslandNPEm Resource From: Vincent, Robert [Robert.Vincent@xenuclear.com]

Sent: Thursday, December 11, 2008 2:48 PM To: Nathan Goodman; Richard Plasse; Stuart Sheldon Cc: Eckholt, Gene F.; Davis, Marlys E.

Subject:

Four PINGP License Renewal RAI Response Letters Attachments: 20081211 Response to NRC RAI Letter dtd 11-19-08.pdf; 20081211 Response to NRC RAI Letter dtd 11-20-08.pdf; 20081211 Response to NRC RAI Letter dtd 11-25-08.pdf; 20081211 Response to NRC RAI Letter dtd 12-1-08.pdf Attached are four RAI response letters that were signed out today. Let me know if you have any questions.

We have one more letter (on drawing issues) that we plan to have out before the holidays. That will probably go out next Thursday.

Bob Vincent X7259 1

Hearing Identifier: Prairie_Island_NonPublic Email Number: 189 Mail Envelope Properties (9FA1D9F2F220C04F95D9394E3CF02DAB013A714F)

Subject:

Four PINGP License Renewal RAI Response Letters Sent Date: 12/11/2008 2:48:24 PM Received Date: 12/11/2008 2:48:44 PM From: Vincent, Robert Created By: Robert.Vincent@xenuclear.com Recipients:

"Eckholt, Gene F." <Gene.Eckholt@xenuclear.com>

Tracking Status: None "Davis, Marlys E." <Marlys.Davis@xenuclear.com>

Tracking Status: None "Nathan Goodman" <Nathan.Goodman@nrc.gov>

Tracking Status: None "Richard Plasse" <Richard.Plasse@nrc.gov>

Tracking Status: None "Stuart Sheldon" <Stuart.Sheldon@nrc.gov>

Tracking Status: None Post Office: enex02.ft.nmcco.net Files Size Date & Time MESSAGE 282 12/11/2008 2:48:44 PM 20081211 Response to NRC RAI Letter dtd 11-19-08.pdf 481802 20081211 Response to NRC RAI Letter dtd 11-20-08.pdf 500448 20081211 Response to NRC RAI Letter dtd 11-25-08.pdf 513808 20081211 Response to NRC RAI Letter dtd 12-1-08.pdf 486732 Options Priority: Standard Return Notification: No Reply Requested: No Sensitivity: Normal Expiration Date:

Recipients Received:

Document Control Desk Page 2 Enclosure (1) cc:

Administrator, Region III, USNRC License Renewal Project Manager, Prairie Island, USNRC Resident Inspector, Prairie Island, USNRC Prairie Island Indian Community ATTN: Phil Mahowald Minnesota Department of Commerce

Enclosure 1 NSPM Responses to NRC Requests for Additional Information Dated November 19, 2008 RAI 2.3.3.9-1 Section 4.3.1.5 of the Safety Evaluation Report for PINGP Units 1 and 2, dated September 6, 1979, discusses various types of wet pipe, deluge, and pre-action dry pipe sprinkler systems provided in the plant areas for fire suppression activities. The sprinkler systems in various areas are:

Fire Sprinkler System Area Wet Pipe Automatic Sprinkler x Turbine Building - Turbine Lube Oil and Systems Control Oil Piping Areas x Air Compressor and Auxiliary Feedwater Pump Rooms x Exit Stairwells x Records Storage Area x Decontamination Area x Water Treatment Area x Warehouse x Hot Lab Area Deluge Systems x Main Auxiliary and Startup Transformers x Turbine Generators Bearings x Turbine Seal Oil Unit x Turbine Lube Oil Reservoir x Oil Storage Room x Charcoal Filter - Auxiliary Building Special Exhaust Filter and the Shield Building Exhaust Filters Pre-action Dry Pipe Sprinkler x Containment Cable Penetration Areas Systems x Screen House Pump Area (Both Levels)

Including the Diesel Cooling Water Pumps and the Diesel Driven Fire Pump The staff requests that the applicant verify whether the above sprinkler systems installed in various areas of the plant are in the scope of license renewal in accordance with 10 CFR 54.4(a) and subject to an AMR in accordance with 10 CFR 54.21(a)(1). If they are excluded from the scope of license renewal and not subject to an AMR, the staff requests that the applicant provide justification for the exclusion.

NSPM Response to RAI 2.3.3.9-1 The wet pipe automatic sprinkler, deluge, and pre-action dry pipe sprinkler sub-systems installed in various areas of the plant for fire suppression are in the scope of license 1

Enclosure 1 NSPM Responses to NRC Requests for Additional Information Dated November 19, 2008 renewal in accordance with 10 CFR 54.4(a) and are subject to an Aging Management Review (AMR) in accordance with 10 CFR 54.21(a)(1).

Wet Pipe Automatic Sprinkler Systems x The Turbine Building - Turbine Lube Oil and Control Oil Piping Areas Sprinkler sub-systems are shown on Drawings LR-39228-2 and 3. See Drawing LR-39228-2, location D-7, Turbine Oil Sprinkler System WPS-18. See Drawing LR-39228-3, location G-4, Turbine Oil Pipe Wet Pipe System WPS-21.

x The Air Compressor and Auxiliary Feedwater Pump Rooms Sprinkler sub-system is shown on Drawing LR-39228-2, location D-3, Air Compressor and Auxiliary Feedwater Pump Area Sprinkler System WPS-10.

x Exit stairwells used for egress or to allow access to manual fire suppression are provided with sprinkler systems throughout the plant. Exit stairwell sprinkler systems are shown on Drawings LR-100282 and LR-39228-2, 3, 4 and 5. See Drawing LR-100282, location D-4, Stairs Wet Pipe Sprinkler System. See Drawing LR-39228-2, location E-5, Stairway Sprinkler System SWP-3 (incorrectly labeled WPS-18), location B-9, Stairway Sprinkler System SWP-5, and location G-9, Stairway Wet Pipe System SWP-6. See Drawing LR-39228-3, location E-2, Stairway Sprinkler System SWP-14 and location H-6, Stairway Sprinkler System SWP-13. See Drawing LR-39228-4, location B-4, Stairway Sprinkler System SWP-12, location B-10, Stairway Sprinkler System SWP-4, location F-5, Stairway Sprinkler System SWP-1 and location C-6, Stairway Sprinkler System SWP-2.

See Drawing LR-39228-5, location A-5, Stairwell sprinklers.

x The Records Storage Area Sprinkler sub-system is shown on Drawing LR-39228-4, location G-8, Record Room System WPS-23.

x The Decontamination Area at Access Control is protected by a wet pipe sprinkler sub-system shown on Drawing LR-39228-4, location A-8, Laundry Room, Toilet Room, Clothes Storage Room and Corridor Sprinkler Systems WPS-20.

x The Water Treatment Area Sprinkler sub-system is shown on Drawing LR-39228-2, location E-9, Turbine Room (East Side) Sprinkler System WPS-9.

x The Warehouse Sprinkler sub-systems are shown on Drawing LR-39228-3. See location B-3, Warehouse Sprinkler & Hose Stations, and location F-9, Warehouse #2 Sprinkler System DE-3.

x The Hot Lab Area Sprinkler sub-system is shown on Drawing LR-39228-4, location C-6, WPS-19 Hot Chemical Laboratory.

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Enclosure 1 NSPM Responses to NRC Requests for Additional Information Dated November 19, 2008 Deluge systems x The Main, Auxiliary and Startup Transformers Deluge sub-systems are shown on Drawings LR-39228-2 and LR-39228-3. See Drawing LR-39228-2, location B-6, B-7 and B-8, Transformer Sprinkler Systems DM-3, DM-2 and DM-1, respectively. See Drawing LR-39228-3, location D-2, D-4 and D-5, Transformer Sprinkler System DM-5, DM-4 and DM-6, respectively.

x The Turbine Generator Bearing Pre-Action sub-systems are shown on Drawings LR-39228-2 and LR-39228-3. See Drawing LR-39228-2, location B-10, Turbine Bearing Fire Protection Pre-action System PA-14. See Drawing LR-39228-3, location B-11, Turbine Bearing Fire Protection Pre-action System PA-15.

x The Turbine Seal Oil Unit Deluge sub-systems are shown on Drawings LR-39228-2 and LR-39228-3. See Drawing LR-39228-2, location D-9, Hydrogen Seal Oil Unit Sprinkler System DA-1. See Drawing LR-39228-3, location G-2, Hydrogen Seal Oil Sprinkler System DA-5.

x The Turbine Lube Oil Reservoir Deluge sub-systems are shown on Drawings LR-39228-2 and LR-39228-3. See Drawing LR-39228-2, location D-4, Turbine Oil Reservoir Area Sprinkler System DA-3. See Drawing LR-39228-3, location G-6, Turbine Oil Reservoir Sprinkler System DA-4.

x The Oil Storage Room Deluge sub-system is shown on Drawing LR-39228-2, location B-3, Turbine Oil Storage Room Sprinkler System DA-2.

x The Charcoal Filter - Auxiliary Building Special Exhaust Filter and the Shield Building Exhaust Filters Deluge sub-systems are shown on Drawing LR-39603-4, location C-4 through E-4 and location E-11 through G-11.

Pre-action Dry Pipe Sprinkler Systems x The Containment Cable Penetration Area Pre-Action Dry Pipe Sprinkler sub-systems are shown on Drawing LR-39228-4, location C-3, D-5, D-8 and C-10, Electrical Penetration Pre-Action System PAD-7, PAD-6, PAD-3 and PAD-4 respectively.

x The Screen House Pump Area (Both Levels) Including the Diesel Cooling Water Pumps and the Diesel Driven Fire Pump Pre-action Dry Pipe Sprinkler sub-system is shown on Drawing LR-39228-3, location B-8, Screenhouse Sprinkler System PAD-9.

The scoping boundaries extend up to and include the installed end devices such as sprinkler heads and spray nozzles. The interconnected piping/fittings, valves, sprinkler heads, spray nozzles and in-line components are within the scope of License Renewal and subject to AMR. Piping/fittings, valves, sprinkler heads, spray nozzles and other in-3

Enclosure 1 NSPM Responses to NRC Requests for Additional Information Dated November 19, 2008 line components are included in LRA Table 2.3.3-9, and AMR aging management evaluations are included in Table 3.3.2-9.

RAI 2.3.3.9-2 LRA Tables 2.3.3-9 and 3.3.2-9 exclude several types of fire protection components that appear on the LRA drawings as within the scope of license renewal or discussed in PINGP CLB documents. These components are listed below:

  • hose connections
  • interior fire hose stations
  • pipe supports
  • dikes for oil spill confinement
  • floor drains and curbs for fire-fighting water
  • backflow prevention devices
  • trash grids and traveling screens
  • flame retardant coating for cables
  • fire retardant intumescent coating for polyurethane foam insulation
  • turbine building smoke removal system components
  • air compressors for safe-shutdown operations For each, determine whether the component should be included in Tables 2.3.3-9 and 3.3.2-9 as component types subject to an AMR, and if not, justify the exclusion.

NSPM Response to RAI 2.3.3.9-2 Fire protection hose connections are within the scope of License Renewal. Hose connections from the plant fire header, hydrants and valves are evaluated as Piping/Fittings and are included in LRA Table 2.3.3-9 and Table 3.3.2-9. Fire hoses, including integral hose connections, are evaluated in LRA Section 2.1.3.2.2. Fire hoses are inspected and tested periodically and must be replaced if they do not pass the test or inspection; these components are short lived and are not subject to Aging Management Review.

Interior fire hose stations are within the scope of License Renewal. Interior fire hose stations components are evaluated as Piping/Fittings and Valves and are included in LRA Table 2.3.3-9 and Table 3.3.2-9.

Pipe supports for fire protection piping are within the scope of License Renewal. See LRA Section 2.4.2 and Table 2.4.2-1 for supports, and Section 2.3.3.9 and Table 2.3.3-9 for fire protection piping. For additional detail and for aging management of fire protection pipe supports, see Table 3.5.2-2 for the component type, Support (... non-ASME piping ...).

4

Enclosure 1 NSPM Responses to NRC Requests for Additional Information Dated November 19, 2008 Fire header couplings are within the scope of License Renewal. Fire header couplings are evaluated as Piping/Fittings and are included in LRA Table 2.3.3-9 and Table 3.3.2-9.

Dikes for oil spill confinement are addressed by the component types, Concrete (...

curbs, walls, slabs ...)" and Steel components (... angles used to contain fuel oil leaks

...)." These component types, as used in the PINGP LRA, include structures that provide intended functions to direct flow and/or provide a fire barrier to prevent the spread of flammable liquids. These components are in scope of License Renewal and protect safety related structures and safe shutdown systems from fire damage.

Concrete floor depressions, part of the concrete slab design, are also used to direct the flow of flammable liquids. These components are located throughout safety related structures and can be found in LRA Tables 2.4.1-1, 2.4.4-1, 2.4.5-1, and 2.4.9-1. For aging management of these concrete and steel components, see LRA Tables 3.5.2-1, 3.5.2-4, 3.5.2-5, and 3.5.2-9.

There is a reinforced concrete wall surrounding the fuel oil receiving tank located outside, adjacent to the south wall of the D5/D6 Diesel Generator Building. However the wall is not in scope of License Renewal. Since the tank performs a support function and not a confinement function, it is not in scope of License Renewal.

Floor drains for fire fighting water are within the scope of License Renewal and are evaluated in the Waste Disposal (WD) System. In general floor drains are highlighted as within the scope of License Renewal per 10 CFR 54.4(a)(2) due to flooding and/or spatial interaction intended functions. Where they may also have an 10 CFR 54.4(a)(3) function, this was not differentiated (for example, see Drawing LR-39248). The Turbine Oil Reservoir and Oil Storage Room drains are specifically discussed in Section 4.5 of the Safety Evaluation Report dated September 9, 1979. These drains are depicted on Drawings LR-39231-1, locations G-3 and H-8, and LR-39231-2, location H-4; and should be highlighted as within the scope of License Renewal per 10 CFR 54.4(a)(3).

Floor drains are evaluated as Piping/Fittings and are included in LRA Table 2.3.3-20 and Table 3.3.2-20. The following changes are required to the LRA:

In LRA Section 2.3.3.20 under System Function Listing, the following function is added:

Code WD-FP Cri 1 Cri 2 Cri 3 Contains SCs relied upon in safety analysis FP EQ PTS AT SB or plant evaluations to perform a function X that demonstrates compliance with 10 CFR 50.48, Fire Protection.

Comment: This system contains floor drains for fire fighting water and oil confinement, such as the Turbine Oil Reservoir and Oil Storage Room drains, that support a Fire Protection function.

5

Enclosure 1 NSPM Responses to NRC Requests for Additional Information Dated November 19, 2008 In LRA Section 2.3.3.20 on Page 2.3-109, second paragraph, second sentence, "plant floor drains," is added to the list of drains which comprise the Waste Liquid sub-system.

In LRA Section 2.3.3.20, Page 2.3-110, the third sentence of the fifth paragraph is revised to read as follows: Portions of the WD System support Fire Protection or Station Blackout event requirements based on the criteria of 10 CFR 54.4(a)(3).

Curbs for fire fighting water are addressed by the component types, Concrete (... walls, slabs and curbs ...), Stainless steel components (... curbs and flow deflectors ...), and Steel components (... curbs ...). These component types as used in the PINGP LRA include structures that provide an intended function to direct flow away from safety related equipment in order to prevent water damage. These components are in scope of License Renewal, and are located throughout safety related structures. They are included in LRA Tables 2.4.1-1, 2.4.4-1, 2.4.7-1, and 2.4.9-1. For aging management of these concrete, stainless steel, and steel components, see LRA Tables 3.5.2-1, 3.5.2-4, 3.5.2-7, and 3.5.2-9.

The PINGP Fire Protection (FP) System is supplied from the Mississippi River and does not include connections from potable water sources. Therefore, the PINGP FP system does not contain backflow prevention devices; as a result they are not included in LRA Table 2.3.3-9 and Table 3.3.2-9. The FP system does include check valves; these are included in LRA Table 2.3.3-9 and Table 3.3.2-9.

Trash grids and traveling screens are addressed in LRA Section 2.3.4.3, Circulating Water (CW) System. The FP pumps draw water from behind the Plant Screenhouse trash grids and screens. During emergency operation, when the circulating water pumps are not in-service, the flows through the trash grids and screens would be insignificant and plugging or failure of the grids and screens is not credible. Therefore, trash grids and traveling screens are not relied upon to perform or support a License Renewal Fire Protection-related Intended Function.

Flame retardant coatings for cables used in penetration seals and used for cable encapsulation are in scope of License Renewal. They are included in LRA Table 2.4.5-

1. For additional detail and for aging management of flame retardant coating for cables, see LRA Table 3.5.2-5 for the component types, Fire barrier penetration seals and Fireproofing for cable and cable tray.

Fire retardant intumescent coatings were originally used on all polyurethane foam piping insulation in areas containing safety related equipment. However, the intumescent coating performed unsatisfactorily and was replaced with materials identified as Armaflex (primer) and Flammastic (mastic sealant) which have better flame spread and smoke density test results when compared to the intumescent coating. This was conveyed in a letter to the NRC dated May 4, 1992. The NRC approved the replacement materials in a letter dated January 14, 1993. These components are in scope of License Renewal, and are identified in Table 2.4.5-1 of the LRA as, Fire 6

Enclosure 1 NSPM Responses to NRC Requests for Additional Information Dated November 19, 2008 barrier penetration seals and Fireproofing components. LRA Table 3.5.2-5 provides additional information on these component types and materials.

Turbine building roof exhaust fans, as well as smoke hatches that are fitted with automatic releases, are within the scope of License Renewal. The Turbine building roof exhaust fans are evaluated in LRA Section 2.3.3.19, Turbine and Administration Building (ZB) System (see Function ZB-FP) and are shown on Drawing LR-39601, location F-2, Turbine Building Roof Vent Fans. The fan and damper are integral to the fan housing and are evaluated as Fan Housings. They are included in LRA Table 2.3.3-19 and Table 3.3.2-19. The Turbine Building smoke hatches are evaluated in LRA Table 3.5.2-5.

Air compressors required for Fire Protection safe-shutdown operation are within the scope of License Renewal. The station and instrument air compressors are evaluated in LRA Section 2.3.3.17, Station and Instrument Air (SA) System (see Function SA-FP) and are shown on Drawings LR-39244 and LR-39253-3. The air compressors are active components and not subject to aging management review; as a result they are not included in LRA Table 2.3.3-17.

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Document Control Desk Page 2 Enclosure (1) cc:

Administrator, Region III, USNRC License Renewal Project Manager, Prairie Island, USNRC Resident Inspector, Prairie Island, USNRC Prairie Island Indian Community ATTN: Phil Mahowald Minnesota Department of Commerce

Enclosure 1 NSPM Responses to NRC Requests for Additional Information Dated November 20, 2008 RAI 4.7.1-1 Discuss the inspection history and results of the piping that has been approved for leak-before-break (LBB) at Prairie Island Units 1 and 2. Discuss the future inspection plans.

NSPM Response to RAI 4.7.1-1 The PINGP piping that has been approved for leak-before-break (LBB) includes the Unit 1 and Unit 2 primary loop (large-bore) piping and the Unit 1 pressurizer surge line. The associated piping and nozzle welds have been periodically examined in accordance with the requirements of ASME Section XI. A review of the past examination history dating back to the beginning of the third inservice inspection interval, which began December 17, 1993 for Unit 1 and December 21, 1994 for Unit 2, indicates that the piping was examined using surface and volumetric inspection techniques. A review of the surface examination results found that some minor surface indications (e.g., small rounded and linear indications) were identified. These indications were evaluated and dispositioned per the requirements of ASME Section XI. Some indications were removed (e.g., by light buffing), while others were found acceptable per Code, and left in place. A review of the volumetric examination results found that some geometric indications were identified but no volumetric indications required corrective action or repair/replacement.

This piping is currently subject to examination in accordance with ASME Section XI, 1998 Edition, including the 1998, 1999 and 2000 Addenda, and the approved Risk Informed Inservice Inspection (RI-ISI) Program. These examinations will continue until the end of the current (fourth) inspection interval. Under the current program, the associated piping and nozzle welds are volumetrically examined. Following completion of the current inspection interval, the PINGP ASME Section XI Inservice Inspection, Subsections IWB, IWC, and IWD Program will be updated as required by 10 CFR 50.55a, and examinations will be conducted accordingly. In addition, future examinations of the cast austenitic stainless steel piping in the Unit 1 and 2 reactor coolant loops may also include enhanced volumetric examinations or component-specific flaw tolerance evaluations as deemed appropriate per the new Thermal Aging Embrittlement of Cast Austenitic Stainless Steel Program.

RAI 4.7.1-2 In Section 4.7.1, second paragraph, the applicant stated that primary coolant piping is made of cast austenitic stainless steel (CASS). In the fourth paragraph, the applicant stated that CASS is used in the pipe fittings. (a) Confirm that pipe fittings and straight sections of the primary coolant piping at Units 1 and 2 are all made of CASS. (b)

Discuss the material used in fabricating the surge lines at Units 1 and 2.

1

Enclosure 1 NSPM Responses to NRC Requests for Additional Information Dated November 20, 2008 NSPM Response to RAI 4.7.1-2 (a) The Unit 1 large bore primary coolant piping fittings (elbows) are fabricated from cast austenitic stainless steel (CASS) (i.e., ASTM A351). The Unit 1 large bore primary coolant piping straight sections are made from forgings (i.e., ASTM A376). All Unit 2 large bore primary coolant piping fittings and straight sections are fabricated from CASS (i.e., ASTM A351).

(b) The Unit 1 pressurizer surge line piping fittings and straight sections are fabricated from forged product forms (i.e.; ASTM A376, A403). The Unit 2 pressurizer surge line piping fittings and straight sections are fabricated from forged product forms (i.e.; ASTM A376, A403).

RAI 4.7.1-3 The applicant submitted LBB analyses for the Unit 1 pressurizer surge line. Confirm that LBB has not been implemented and LBB analyses have not been submitted to the NRC for the Unit 2 pressurizer surge line.

NSPM Response to RAI 4.7.1-3 Leak-Before-Break (LBB) technology has not been implemented and LBB analyses have not been submitted to the NRC for the PINGP Unit 2 pressurizer surge line.

RAI 4.7.1-4 Nickel-based Alloy 600/82/182 material in the pressurized water reactor environment has been shown to be susceptible to primary water stress corrosion cracking (PWSCC).

(a) Identify any piping that has been approved for LBB for both units which contain Alloy 82/182 weld metal and Alloy 600 components. (b) If LBB piping contains Alloy 600/82/182 material, discuss any mitigation measures (such as weld overlays or mechanical stress improvement) that have been or will be implemented to reduce the effects of PWSCC on the LBB piping components. (c) Discuss the inspection history and future inspection frequency of the Alloy 81/182 dissimilar metal butt welds (see Question number 1 above).

NSPM Response to RAI 4.7.1-4 (a) PINGP has no piping that has been approved for Leak-Before-Break (LBB) which contains Alloy 82/182 weld metal or Alloy 600 components. Note that the Unit 2 pressurizer surge nozzle-to-safe end dissimilar metal weld is constructed of Alloy 82; however, this piping has not been approved for LBB.

(b) As previously stated, the LBB piping at PINGP does not contain any Alloy 600/82/182 material. However, to mitigate the effects of primary water stress corrosion 2

Enclosure 1 NSPM Responses to NRC Requests for Additional Information Dated November 20, 2008 cracking (PWSCC) on the Unit 2 pressurizer surge nozzle weld, a full structural weld overlay (FSWOL) on the pressurizer surge nozzle-to-safe end dissimilar metal and safe end-to-reducer stainless steel butt welds was recently installed during the PINGP Unit 2 refueling outage (2R25). The NRC authorized the installation of the FSWOL in a letter dated June 15, 2008 [ML081360646].

(c) The only Alloy 82/182 dissimilar metal butt weld in the pressurized water reactor environment at PINGP is the Unit 2 pressurizer surge nozzle-to-safe end dissimilar metal weld. This weld is located on the Unit 2 pressurizer surge line; this piping has not been approved for Leak-Before-Break (LBB).

The PlNGP Unit 2 pressurizer surge nozzle-to-safe end weld was ultrasonically examined in November 2006 per ASME Section XI, Appendix VIII, Supplement 10. The examination met the ASME Section XI and EPRI MRP-139, "Primary System Piping Butt Weld Inspection and Evaluation Guidelines" requirements for examination coverage. No PWSCC indications were detected.

Ultrasonic examinations of the Unit 2 surge nozzle-to-safe end dissimilar metal weld were conducted in September 2008, prior to installation of the full structural weld overlay (FSWOL). The examinations were performed in accordance with ASME Section XI, Appendix VIII, Supplement 10. No recordable indications were identified.

In October 2008, following installation of the FSWOL, ultrasonic examinations (UT) were performed of the new overlay weld and the nozzle-to-safe end dissimilar metal weld.

100 percent of the Code required volume was achieved during the examinations. The UT examinations resulted in no recordable indications.

In a letter dated January 15, 2008 [ML081510906], NSPM proposed alternative requirements to ASME Section XI to provide for the installation and examination of the FSWOL in Alternative Request No. 2-RR-4-8, Revision 1. The NRC staff authorized the use of Alternative Request 2-RR-4-8, Revision 1, in a letter dated June 15, 2008

[ML081360646]. Enclosure 2, Table 2 of Alternative Request 2-RR-4-8, Revision 1, requires inservice examinations to be conducted ultrasonically with the examination volume defined in ASME Section XI, Nonmandatory Appendix Q, Figure Q-4300-1.

Inservice examinations as described in Q-4300 will be performed in accordance with the requirements of MRP-139, with the additional requirement of at least one ultrasonic examination within ten years of the FSWOL application. Additionally, by letter dated May 7, 2008 [ML081280890], NSPM agreed that if indications were found in the pre-application ultrasonic examination, the first inservice examination will be performed during the first or second outage following FSWOL application. The MRP-139 guidance for ISI goes beyond current ASME Code inspection requirements for PINGP Unit 2.

The NRC found that the inservice examination requirements in the May 7, 2008 letter, and Enclosure 2, Table 2 of Alternative Request 2-RR-4-8, Revision 1, were consistent with, or more conservative than, the ASME Code,Section XI, Appendix Q.

3

Enclosure 1 NSPM Responses to NRC Requests for Additional Information Dated November 20, 2008 RAI 4.7.1-5 The applicant discusses Aging Management Program (AMP) B.2.1.41, Thermal Aging Embrittlement Of Cast Austenitic Stainless Steel (CASS), in Appendix B of the license renewal application. However, Section 4.7.1 does not mention this AMP for managing the LBB piping that is made of CASS. Discuss how CASS material of the LBB piping will be managed because AMP B.2.1.41 does not seem to be used to monitor the CASS components in the LBB piping systems for thermal aging embrittlement.

NSPM Response to RAI 4.7.1-5 As specified in PINGP LRA Table 3.1.2-2 (Page 3.1-60), the Thermal Aging Embrittlement of Cast Austenitic Stainless Steel (CASS) Program manages reduction of fracture toughness due to thermal aging embrittlement of CASS piping and fittings in the Reactor Coolant System (RCS). This is consistent with NUREG-1801, Line Item IV.C2-

4. The Unit 1 and 2 RCS piping and fittings constructed of ASTM A351-CF8M material are included in the scope of AMP B2.1.39, Thermal Aging Embrittlement of Cast Austenitic Stainless Steel (CASS) Program.

RAI 4.7.1-6 By letter dated May 19, 2000, the NRC forwarded to the Nuclear Energy Institute an evaluation of thermal aging embrittlement of CASS components [ML003717179]. In the NRCs evaluation, the staff provided its positions on how to manage CASS components.

Discuss how the CASS components in the LBB piping at both units satisfy the staff positions in its evaluation dated May 19, 2000.

NSPM Response to RAI 4.7.1-6 The letter dated May 19, 2000, "License Renewal Issue No. 98-0030, Thermal Aging Embrittlement of Cast Austenitic Stainless Steel Components," provided the NRC staffs evaluation and proposed resolution of the subject issue. As presented in the letter, the staff provided its position for management, during the license renewal period, of thermal aging embrittlement in primary system components constructed of cast austenitic stainless steel (CASS). This position has since been incorporated as an aging management program described in NUREG-1801, Chapter XI, Program XI.M12, Thermal Aging Embrittlement of Cast Austenitic Stainless Steel (CASS). The program includes (a) determination of the susceptibility of CASS components to thermal aging embrittlement and (b) for potentially susceptible components, aging management is accomplished through either enhanced volumetric examination or plant- or component-specific flaw tolerance evaluation.

As shown in LRA Table 3.1.2-2, PINGP relies on the Thermal Aging Embrittlement of Cast Austenitic Stainless Steel (CASS) Program to manage the reduction of fracture toughness in CASS Reactor Coolant (RC) System piping and fittings. As described in LRA Section B2.1.39, the PINGP Thermal Aging Embrittlement of CASS Program is a 4

Enclosure 1 NSPM Responses to NRC Requests for Additional Information Dated November 20, 2008 new program that will be consistent with the recommendations of NUREG-1801, Chapter XI, Program XI.M12, Thermal Aging Embrittlement of Cast Austenitic Stainless Steel (CASS).

The PINGP Thermal Aging Embrittlement of CASS Program scope includes the following CASS piping components which have been approved for Leak-Before-Break (LBB):

x Unit 1 large bore primary coolant piping fittings (elbows) which are constructed of statically cast ASTM A351, Type CF8M material.

x Unit 2 large bore primary coolant piping (straight sections) which is constructed of centrifugally cast ASTM A351, Type CF8M material.

x Unit 2 large bore primary coolant piping fittings (elbows) which are constructed of statically cast ASTM A351, Type CF8M material.

The PINGP Thermal Aging Embrittlement of CASS Program includes a determination of the susceptibility of CASS components to thermal aging embrittlement based on casting method, molybdenum content, and percent ferrite. After applying the screening criteria specified in the May 19, 2000 letter, Section 3.0 and NUREG-1801, XI.M12, Element 1, the following CASS components, in the scope of the program, were determined to be potentially susceptible to thermal aging embrittlement:

x A segment of straight RC System piping is potentially susceptible to thermal aging embrittlement due to its high molybdenum content and ferrite content which exceeds 20% by weight:

o Unit 2 RC System 27.5 I.D. cold leg piping in Loop A, Heat Number C-1737 x The following RC System fittings are potentially susceptible to thermal aging embrittlement due to their high molybdenum content and ferrite content which exceeds 14% by weight:

o Unit 1 RC System 27.5 ID x 35D Elbow, Heat No. 33676 o Unit 1 RC System 31.0 ID x 90D Elbow w/ Splitter, Heat No. 13704 o Unit 1 RC System 31.0 ID x 90D Elbow w/ Splitter, Heat No. 19114 o Unit 2 RC System 27.5 ID x 35D Elbow, Heat No. 37758-2 o Unit 2 RC System 31.0 ID x 40D Elbow, Heat No. 38992-3 o Unit 2 RC System 31.0 ID x 90D Elbow, Heat No. 39231-2 For the CASS components determined to be potentially susceptible to thermal aging embrittlement, in accordance with criteria specified in the May 19, 2000 letter, Section 3.0, and in NUREG-1801, XI.M12, Elements 3 and 4, the program will provide enhanced volumetric examinations to detect and size cracks, or component-specific flaw tolerance evaluations will be performed. The program will provide enhanced volumetric examinations on the base metal determined to be limiting due to applied stress, operating time, and environmental considerations, using examination methods 5

Enclosure 1 NSPM Responses to NRC Requests for Additional Information Dated November 20, 2008 that meet the criteria of ASME Section XI, Appendix VIII. Alternatively, component-specific flaw tolerance evaluations will be performed using specific geometry and applied stress to demonstrate that the thermally-embrittled material has adequate toughness.

Per NUREG-1801, XI.M12, Element 5, the PINGP Thermal Aging Embrittlement of Cast Austenitic Stainless Steel (CASS) Program will incorporate the inspection schedule of IWB-2400 or IWC-2400 for potentially susceptible CASS components using ASME examination methods for the detection of cracking. Alternatively, component-specific flaw tolerance evaluations will be performed. Consistent with the criteria specified in the May 19, 2000 letter, Section 3.0, and in NUREG-1801, XI.M12, Element 6, flaws detected in CASS components will be evaluated in accordance with the applicable procedures of IWB-3500 or IWC-3500 in Section XI of the ASME Code. Alternatively, flaw tolerance evaluation for components with ferrite content up to 25% will be performed according to the principles associated with IWB-3640 procedures for submerged arc welds disregarding the Code restriction of 20% ferrite in IWB-3641(b)(1).

PINGP does not have RC System CASS piping with >25% ferrite. Per NUREG-1801, XI.M12, Element 7, repair and replacement of CASS components will be performed in accordance with the requirements of ASME Section XI, Subsection IWA-4000.

RAI 4.7.1-7 Explain whether the current fatigue crack growth analyses, as discussed in the fatigue crack growth section, are performed for 60 years. If not, discuss whether the current fatigue crack growth analyses, which are analyzed for 40 years, are applicable to 60 years. Provide the technical basis in detail.

NSPM Response to RAI 4.7.1-7 Large Primary Loop Pipe Rupture for PINGP Units 1 and 2 As reported in Section 6.0 of WCAP-10640-NP/WCAP-10639-P (for Unit 1) and WCAP-10928-NP/WCAP-10929-P (for Unit 2), the purpose of the fatigue crack growth analyses was to determine the sensitivity of the primary coolant system to the presence of small cracks. For the Unit 1 and Unit 2 large primary loop piping, a finite element stress analysis was completed for one of the highest-stressed cross sections of a plant typical in geometry and operational characteristics to any Westinghouse PWR system. Crack growths calculated in the selected region are representative of the entire primary loop.

All normal, upset, and test conditions were considered, and circumferentially oriented surface flaws were postulated in the region, assuming the flaw was located in three different locations. Fatigue crack growth rate laws were used. The results of fatigue crack growth at 40 years for semi-elliptical surface flaws of circumferential orientation and various depths show that crack growth is very small at all three locations.

The TLAAs associated with the fatigue crack growth analyses are the normal, upset, and test conditions (i.e., NSSS design transients) that were used to calculate fatigue 6

Enclosure 1 NSPM Responses to NRC Requests for Additional Information Dated November 20, 2008 crack growth at 40 years. These design transients have not been changed or increased for license renewal as discussed in Section 4.3 of the PINGP LRA. The existing numbers of thermal and loading cycles for each transient remain valid for 60 years of plant operation. Therefore, the fatigue crack growth calculations reported in WCAP-10640-NP/WCAP-10639-P (Unit 1) and WCAP-10928-NP/WCAP-10929-P (Unit 2) remain valid for the period of extended operation in accordance with 10 CFR 54.21(c)(1)(i).

Pressurizer Surge Line Rupture for PINGP Unit 1 As reported in Section 6.0 of WCAP-12876-NP/WCAP-12877-P, the purpose of the fatigue crack growth analyses for the PINGP Unit 1 pressurizer surge line was to determine the sensitivity of the pressurizer surge line to the presence of small cracks when subjected to the transients discussed in WCAP-12839, Structural Evaluation of Prairie Island Unit 1 Pressurizer Surge Line, Considering the Effects of Thermal Stratification.

For the Unit 1 pressurizer surge line, fatigue crack growth analyses were performed at two locations where detailed fracture mechanics evaluations were completed: (1) surge line piping near the reactor coolant hot leg nozzle, and (2) surge line piping near the pressurizer surge nozzle. Various initial semi-elliptical surface flaws with a six-to-one aspect ratio were assumed to exist. The largest initial flaw assumed was one with a depth equal to 10% of the nominal wall thickness. A fatigue crack growth law for austenitic stainless steel in a PWR environment was developed and used in the crack growth analyses. The results of fatigue crack growth at 40 years for an initial flaw of 10% nominal wall thickness show that crack growth is very small at both locations.

The TLAAs associated with the fatigue crack growth analyses are the normal, upset, and test conditions (i.e., NSSS design transients) and pressurizer surge line transient sub-events (to reflect stratification effects) presented in WCAP-12839 that were used to calculate fatigue crack growth at 40 years. The NSSS design transients and pressurizer surge line sub-events have not been changed or increased for license renewal as discussed in Section 4.3 of the PINGP LRA. The existing numbers of thermal and loading cycles for each transient remain valid for 60 years of plant operation. Therefore, the fatigue crack growth calculations reported in WCAP-12876-NP/WCAP-12877-P remain valid for the period of extended operation in accordance with 10 CFR 54.21(c)(1)(i).

For additional technical details associated with the PINGP Leak-Before-Break Analyses, please refer to the proprietary Westinghouse WCAP reports (i.e., those designated with

-P suffix above), which have been previously submitted to the NRC. See PINGP LRA, Section 4.0 References, References 15, 17, and 19 on Page 4.7-8.

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Enclosure 1 NSPM Responses to NRC Requests for Additional Information Dated November 20, 2008 RAI 4.7.1-8 Discuss whether the Unit 1 pressurizer surge line has experienced temperature transients in which temperature differences exceeded the design transients used in the LBB analyses. If out-of-limit transients occurred, describe how the LBB analyses for the Unit 1 surge line were re-evaluated to determine their acceptability.

NSPM Response to RAI 4.7.1-8 In accordance with Section 1.1 of WCAP-12876-NP/WCAP-12877-P, the results of the pressurizer surge line thermal stratification evaluation described in WCAP-12839 were used in the leak-before-break (LBB) analyses of the Unit 1 pressurizer surge line.

PINGP monitors thermal stratification in the pressurizer surge line by tracking the maximum temperature differential between the pressurizer water and the Reactor Coolant System (Loop B) hot leg during heatups and cooldowns to ensure compliance with the thermal stratification transients defined in WCAP-12839. There have been no instances in which temperature differences between the pressurizer and RCS have exceeded the design transients defined in WCAP-12839. In addition, the numbers of heatup and cooldown cycles experienced by the surge line are within the cycle limits specified in the analysis. Therefore, there have been no instances where the Unit 1 pressurizer surge line has experienced temperature transients that have exceeded the design transients used in the LBB analyses.

RAI 2.5 In the license renewal application, the applicant described the station blackout recovery paths for license renewal. As the licensee did not specifically exclude the associated control circuits and structures for the switchyard circuit breakers, it is assumed that these components are included in the scope of license renewal. In accordance with Title 10 of the Code of Federal Regulations (10 CFR) Section 54.4(a)(3) and License Renewal Sections 2.1.3.1.3 and 2.5.2.1.1 of the Standard Review Plan, the control circuits and structures associated with the circuit breaker should be in the scope of license renewal. Please confirm that these components are within the scope of license renewal.

NSPM Response to RAI 2.5 The station blackout recovery paths for license renewal purposes are described in the PINGP LRA. The control circuits and structures associated with the station blackout recovery path switchyard circuit breakers are in the scope of license renewal.

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Document Control Desk Page 2 Enclosure (1) cc:

Administrator, Region III, USNRC License Renewal Project Manager, Prairie Island, USNRC Resident Inspector, Prairie Island, USNRC Prairie Island Indian Community ATTN: Phil Mahowald Minnesota Department of Commerce

Enclosure 1 NSPM Responses to NRC Requests for Additional Information Dated November 25, 2008 RAI 3.3.2.2.6-1 Prairie Island Nuclear Generating Plant (PINGP) Units 1 and 2 have Boraflex that is no longer credited for criticality in the spent fuel pools. There is no indication whether or not they still monitor the Boraflex for degradation. Past operating experience indicates that there can be blistering and bulging of the Boraflex material and the cladding surrounding the material. This can cause potential fuel handling safety issues.

Although Boraflex is not credited for criticality in the PINGP Unit 1 and 2 spent fuel pools, degradation of the material may impede safe handling of the spent fuel if blistering and/or bulging of the rack occurs. How will potential degradation of Boraflex material be identified and monitored during the proposed period of extended operation?

If degradation of Boraflex is identified, what mitigation strategies will be employed?

NSPM Response to RAI 3.3.2.2.6-1 The spent fuel storage racks are described in the PINGP USAR, Section 10.2.1.

Criticality is prevented by the design of the racks which limits fuel assembly interaction by fixing the minimum separation between assemblies, and by maintaining soluble neutron poison in the spent fuel pool water. No mitigative strategy is required for monitoring the spent fuel pool Boraflex material used in the design of spent fuel storage rack fuel module assemblies. The design of the PINGP spent fuel storage rack fuel module assemblies allows for the release of gasses created by the degrading Boraflex material without degrading the surrounding stainless steel material.

The spent fuel storage rack fuel module assembly design at PINGP incorporates Boraflex which differs from the design that incorporates Boral'. Boraflex is a material composed of 46% silica, 4% polydimethyl, and 50% boron carbide. The fuel module assemblies consist of an inner stainless steel casing, a layer of Boraflex neutron absorbing material, and an outer stainless steel casing (see sketch below). The inner and outer square stainless steel casings are tubular. The outer casing holds the Boraflex in place and is only one-quarter the thickness of the inner casing. The outer casing is attached to the inner casing by four spot welds at the top and bottom of the outer casing on each of the four sides. Thus, the outer casing is not leak tight. This vented cavity design allows the release of gasses and ingress of water to alleviate the potential for cell wall bulging as a result of the Boraflex material off gassing.

Industry OE indicates that Boraflex degrades over time, but the degradation process does not impede the ability to remove or accept fuel since the fuel module assemblys open flow design allows gasses to vent safely to the spent fuel pool water. Bulging, blistering, or other deformation, known to occur in poorly vented designs, is not applicable at PINGP.

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Enclosure 1 NSPM Responses to NRC Requests for Additional Information Dated November 25, 2008 Sketch of Spent Fuel Rack Fuel Module Assembly Although not in use at PINGP, Boral' is another neutron absorber material used in the design of spent fuel storage rack fuel module assemblies. It is technically a cermet, and is classified as a metal matrix neutron absorber manufactured by hot rolling a cubic aluminum ingot containing powdered aluminum and boron carbide to a final gage.

Sheets of Boral' are encapsulated between aluminum sheets to form storage tubes.

Industry operating experience indicates that this design was not properly vented resulting in gas pressure buildup between the sheets causing blistering, deformation and/or swelling of the module assemblies. This experience with Boral' is not applicable to the Boraflex used at PINGP.

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Enclosure 1 NSPM Responses to NRC Requests for Additional Information Dated November 25, 2008 RAI 2.1.1.4.3-1 NUREG 1801, Generic Aging Lessons Learned Report, Volume 2, Revision 1, (GALL)

AMP XI.S8, Protective Coating Monitoring and Maintenance Program, is not credited for aging management in the licensees application. In the application it states that PINGP does not credit coatings inside containment to assure that the intended functions of coated structures and components are maintained. However, in addition to using the Protective Coating Monitoring and Maintenance Program to ensure the function of coated structures and components, the GALL Report states that Proper maintenance of protective coatings inside containment is essential to ensure operability of post-accident safety systems that rely on water recycled through the containment sump/drain system. Although the applicant does not credit the program for aging management, there needs to be adequate assurance that there is proper maintenance of the protective coatings in containment, such that they will not degrade and become a debris source that may challenge the Emergency Core Cooling Systems performance.

Therefore the staff requires the following additional information:

Please describe in detail the coatings assessment program referenced in the supplemental response to Generic Letter 2004-02 (dated February 28, 2008). How will the program ensure that there will be proper maintenance of the protective coatings inside containment and ensure operability of post-accident safety systems that rely on water recycled through the containment sump/drain system in the extended period of operation? Also, describe the frequency and scope of the inspections, acceptance criteria, and the qualification of personnel who perform containment coatings inspections.

NSPM Response to RAI 2.1.1.4.3-1 The coatings assessment program at PINGP, described in the supplemental response to GL 2004-02, "Potential Impact of Debris Blockage on Emergency Recirculation during DBA at Pressurized-Water Reactors" (dated 2-28-08), ensures proper maintenance of coatings through implemented activities that perform inspections and assessment of the condition of coatings inside containment to confirm that the volume of debris that could block the sump recirculation strainers remains conservatively low.

Plant procedures provide the means to check the condition of coatings as a potential source of debris that could block the sump recirculation strainers. These procedures provide requirements for personnel qualification, inspection procedures, criteria for recording degradation, acceptance criteria, and tracking of unqualified coatings and degraded coatings. Containment coatings are subject to ongoing oversight that ensure compliance with the current licensing basis. These activities, however, do not prevent coating failures, and are used only to minimize debris that could be generated during a LOCA.

In accordance with the PINGP coating assessment program, a visual inspection for degraded qualified coatings inside the Containment Building is performed every outage.

Degraded qualified coating is a previously qualified coating that exhibits any defects 3

Enclosure 1 NSPM Responses to NRC Requests for Additional Information Dated November 25, 2008 such as blistering, cracking, flaking, peeling, delaminating or rusting. An inspection for unqualified coatings, to verify compliance with the design basis for the sump screen, is performed every other outage, and was completed for both Units in 2008. An unqualified coating is a coating that cannot be attested to having passed the required laboratory testing, including irradiation and simulated Design Basis Accident (DBA), or has inadequate quality documentation to support its use as being DBA qualified.

Unqualified coating is found on equipment such as motor control centers, control valves, unistrut, cabinets, etc., and is applied by the original equipment manufacturer.

The scope of coatings inspections include interior accessible coated surfaces of the Reactor Containment Vessels, Unit 1 and Unit 2, and the equipment permanently contained therein.

Acceptance criteria for coatings are based on industry guidance in ASTM D714-04, Standard Method for Evaluating Degree of Blistering of Paints and ASTM D610-01, Standard Method for Evaluating Degree of Rusting of Painted Steel Surfaces.

Evidence of a degraded condition includes blistering, cracking, flaking, peeling, delaminating, rusting and discoloration. Any degraded condition is documented and measurements are taken to clearly characterize the degradation. When the condition of the coating is in question, a destructive test can be performed to more accurately assess the condition of the coating. Destructive test methods include ASTM D4541, Test Method for Pull-Off Strength of Coatings Using Portable Adhesion Testers, or D6677, Standard Test Method for Evaluation by Knife. Any identified degradation is dispositioned in accordance with the Corrective Action Process.

The method of performing the coatings inspection, including the degradation recording criteria, is based on ASTM D5163, Standard Guide for Establishing Procedures to Monitor the Performance of Coating Service Level 1 Coating Systems in an Operating Nuclear Power Plant."

Qualification of personnel who perform the containment coatings inspections is in accordance with ANSI N45.2.6 as defined in the PINGP coating assessment program.

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Enclosure (1) cc:

Administrator, Region III, USNRC License Renewal Project Manager, Prairie Island, USNRC Resident Inspector, Prairie Island, USNRC Prairie Island Indian Community ATTN: Phil Mahowald Minnesota Department of Commerce

Enclosure 1 NSPM Responses to NRC Requests for Additional Information Dated December 1, 2008 RAI 2.4.1-1 Due to lack of clarity in the license renewal application (LRA) Tables 2.4.1-1 and 3.5.2-1, please confirm/clarify if the Spent Fuel Pool (SFP) Divider Gates, the SFP leak-chase channels, and the fuel transfer canal upending frame are structural components in the scope of license renewal and subject to an aging management review (AMR). If yes, include their scoping, screening and AMR results, as appropriate, or clarify the location in the LRA where these components are included. If not, please provide justification for exclusion.

NSPM Response to RAI 2.4.1-1 Spent Fuel Pool (SFP) Divider Gates are not in scope of license renewal since they perform no intended function. As discussed in USAR Section 10.2.2.3, to protect against complete loss of water in the spent fuel pool, spent fuel pool cooling system piping connections enter the top of the pool. The drain connection from the transfer canal to the CVSC holdup tank recirculation pump is at the canals bottom. Even if the water in the transfer canal were completely drained with the SFP gate removed, the active portion of the spent fuel would not be uncovered. This is because the bottom of the gate connection in the wall separating the transfer canal from the spent fuel pool is at an elevation that would preclude complete drainage.

SFP leak-chase channels are in scope of license renewal. There components are located in the Auxiliary Building, are fabricated from stainless steel, and are located in an embedded-in-concrete environment. See LRA Table 2.4.1-1 on page 2.4-9 (i.e.,

stainless steel components), and Table 3.5.2-1 on page 3.5-77 (i.e., stainless steel components (embedded members)).

The fuel transfer canal upender (or tipping device) is in scope of license renewal. The upending frame is part of the fuel transfer tipping device identified in the LRA Section 2.4.3, page 2.4-18. See LRA Table 3.5.2-3 on pages 3.5-115 and 3.5-116 for aging management of the fuel transfer tipping devices.

RAI 2.4.3-1 In Updated Final Safety Analysis Report (UFSAR) Section 12.2.6, the applicant states that in order to assure the stability and prevent toppling and over-traveling of the containment polar crane or its components, the features incorporated in its design include: (i) up-kick lugs fastened to each truck; (ii) overturning locks fastened to each truck; and (iii) positive wheel stops. Also, in UFSAR Section 12.2.9, the applicant indicates that the spent fuel pool bridge crane, auxiliary building crane and the turbine building crane are protected against tipping, derailments and uncontrolled movements by features that include: (i) crane bridge and trolley being equipped with fixed, fitted rail yokes; and (ii) positive wheel stops and bumpers. From LRA Section 2.4.3, Table 2.4.3-1 and Table 3.5.2-3, it is not clear if the above noted structural components and fasteners of the cranes are included in-scope of license renewal and subject to an AMR.

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Enclosure 1 NSPM Responses to NRC Requests for Additional Information Dated December 1, 2008 Please confirm if these crane components have been screened in as items requiring an AMR. If yes, indicate where these items have been included in the LRA. If not, provide the technical bases for their exclusion.

NSPM Response to RAI 2.4.3-1 Structural components and fasteners for the containment polar crane (up-kick lugs, overturning locks, positive wheel stops), spent fuel pool bridge crane, auxiliary building crane, and the turbine building crane (fixed, fitted rail yokes, and positive wheel stops and bumpers) identified in Sections 12.2.6 and 12.2.9 of the USAR, are in-scope of License Renewal and subject to an AMR. They are included in the LRA description in Section 2.4.3 which characterized them as miscellaneous load carrying components, and in Table 2.4.3-1 under the component heading, Cranes - Rails and Cranes -

Structural Girders. These components are further defined in Table 3.5.2-3 as Cranes -

structural girders (load carrying structural members, welded and bolted connections

....), and Cranes -rails (rails and associated welded and bolted connections ....).

Bumpers are considered subcomponents of the crane structural assembly and are not explicitly called out.

RAI 2.4.7-1 In LRA Section 2.4.7, the system function listing under code RCV-04, Reactor Containment Vessels and their internal structures provide shielding against high energy line breaks, indicates scoping under 10 CFR 54.4(a)(2), which corresponds to all non-safety related systems, structures and components, whose failure could prevent satisfactory accomplishment of any of the functions identified in 10 CFR 54.4(a)(1). The comment under this item on LRA page 2.4-38 states that: Reactor Containment Vessels and their internal structures are designed to withstand the effects of high energy line breaks without loss of function. Reinforced concrete walls and steel structures inside each Reactor Containment Vessel shield safety related equipment from the effects of a HELB. The NRC staff finds that the above stated structures and structural components are generally safety-related and are in scope in accordance with 10 CFR 54.4(a)(1). Please address the inconsistency.

NSPM Response to RAI 2.4.7-1 Criterion 10 CFR 54.4(a)(2), as it applies to Code RCV-04 on page 2.4-38 of the LRA, is used to describe the HELB protection function applicable to certain non-safety related concrete and steel structures inside each Reactor Containment Vessel including whip restraints and jet impingement shields whose only function is to provide HELB protection for safety related equipment. NEI 95-10, Appendix F, Section 3.4 states that:

NSR whip restraints, jet impingement shields, blowout panels, etc., that are designed and installed to protect SR equipment from the effects of a HELB, are within the scope of license renewal per 10 CFR 54.4(a)(2).

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Enclosure 1 NSPM Responses to NRC Requests for Additional Information Dated December 1, 2008 There are also concrete and steel structures inside the reactor containment vessels that perform a HELB function in combination with safety related functions such as missile protection and structural support to safety related components. In an attempt to avoid confusion, the HELB system function was only used to identify non-safety related structures whose only function is to provide HELB protection for safety related equipment. LRA Table 3.5.2-7 provides a list of safety related concrete and steel structures with multiple functions, one of which is HELB protection.

RAI 2.4.7-2 Because of lack of clarity in LRA Tables 2.4.2-1, 2.4.7-1, 3.5.2-2, 3.5.2-7 and the corresponding LRA sections, please indicate where in the LRA are the scoping, screening and AMR results of structural supports (vertical and lateral, as appropriate) for steam generators, reactor coolant pumps and the reactor vessel included. If these structural components were inadvertently not included, please provide their scoping, screening and AMR results, otherwise justify the exclusion.

NSPM Response to RAI 2.4.7-2 Supports for the reactor vessels, steam generators, and reactor coolant pumps are identified in the PINGP USAR, Section 12.2.4 and Table 12.2-1, as Class 1 structures consistent with Chapter III.B1.1 of NUREG-1801. LRA Table 3.5.2-2 refers to them by the component type, Support (... Class 1 vessels, exchangers, and pumps ...). Only the Unit 2 steam generator supports and the Units 1 and 2 reactor coolant pump supports are installed using high strength bolts, and therefore Table 3.5.2-2 specifically identifies these supports for this application.

LRA Section 2.4.2 includes a list of in-scope component supports which includes pressure vessels, heat exchangers, and pumps, and LRA Table 2.4.2-1 combines all in-scope supports under the component heading, Support.

RAI 2.4.8-1 Please confirm if there are any ductbanks and manholes in the yard that are safety-related or important-to-safety or required for regulated events that may be within the scope of license renewal and subject to an AMR. If there are, please provide their scoping, screening and AMR results.

NSPM Response to RAI 2.4.8-1 There are no ductbanks in scope of license renewal, and only one manhole is in scope and subject to an AMR. The single manhole, in scope for the SBO regulated event, is located about 100 feet west of the Security Building. It provides access to splices in the 13.8 kV cables that run from the switchyard to the Cooling Tower Equipment House.

License Renewal Boundary drawing LR-193817, entitled, PINGP Site Layout of the 3

Enclosure 1 NSPM Responses to NRC Requests for Additional Information Dated December 1, 2008 Owner Controlled Area, provides its location (Item 57, coordinate D6). LRA Section 2.4.8 provides a description of the manhole structure, and Table 2.4.8-1 identified its components as Concrete and Steel Components. Table 3.5.2-8 further defines the concrete portion of the structure as Concrete (... cable vault...), and its metal components as Steel components (... miscellaneous structures/equipment items ...).

The aging effects for the manhole structure are managed by the Structures Monitoring Program based on the results of the AMR.

RAI 2.4.11-1 Section 1.3.2 of the UFSAR states that the plant screenhouse houses the cooling water pumps, fire pumps, circulating water pumps, trash racks and traveling screens. Due to lack of clarity in LRA Tables 2.4.11-1 and 3.5.2-11, please confirm the inclusion or exclusion of the trash racks and traveling screens as structural components within the scope of license renewal and subject to an AMR. If they were not included as an oversight, please provide a description of their scoping and AMR. If they are included elsewhere in the LRA, please indicate the location. If they are excluded from the scope of license renewal and AMR, please provide the basis for their exclusion.

NSPM Response to RAI 2.4.11-1 The trash racks and traveling screen support components are in scope of License Renewal, and the aging effects are managed by the RG 1.127, Inspection of Water-Control Structures Associated with Nuclear Power Plants Program. See LRA Table 2.4.11-1 which identifies the components as Steel Components and see Table 3.5.2-11 which further defines the components as Steel components (Screenhouse trash racks, safeguards traveling screen frames, safeguards bay gates, fasteners ...). The traveling screen portion of the screen assembly is active and therefore, does not require an AMR.

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