ML060900288

NMC Responses to NRC Requests for Additional Information Relating to License Renewal Dated March 8, 2006

ML060900288
Person / Time
Site:	Palisades
Issue date:	03/30/2006
From:	Harden P Nuclear Management Co
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
Download: ML060900288 (29)

Text

Palisades Nuclear Plant Operated by Nuclear Management Company, LLC March 30,2006 10 CFR 54 U. S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20555 Palisades Nuclear Plant Docket 50-255 License No.

DPR-20 NMC Responses to NRC Requests for Additional lnformation Relating to License Renewal Dated March 8, 2006 In a letter dated March 8, 2006, the NRC transmitted two Requests for Additional lnformation (RAI) relating to the Application for Renewed Operating License - Palisades Nuclear Plant dated March 22,2005. The Nuclear Management Company (NMC) responses to those questions are provided in Enclosure

1. In addition, in a meeting on February 14, 2006, and in other subsequent discussions, the NRC has raised follow up questions about several previous NMC responses to NRC Requests for Additional Information. The NMC responses to those questions are provided in Enclosure

2. Please contact Mr. Robert Vincent, License Renewal Project Manager, at 269-764-2559, if you require additional information. Summarv of Commitments This letter contains two new commitments, to read as follows: Palisades procedures will be enhanced to inspect and document the internal condition of applicable components, in-scope for license renewal, when maintenance provides an opportunity. Applicable components are those that have an internal environment of water, are constructed of materials that are potentially susceptible to internal aging degradation in a wetted environment, but are not subject to another Aging Management Program (e.g., Water Chemistry, Open Cycle Cooling) that would manage the internal environment such that aging degradation of the internal surfaces would not be expected.

NMC will submit for NRC review either a technical discussion that provides a more detailed basis for concluding that underclad cracking is not a TLAA at 27780 Blue Star Memorial Highway 8 Covert, Michigan 49043-9530 Telephone: 269.764.2000 Palisades, or a description to be incorporated into LRA Section 4 and Appendix A which describes underclad cracking as a TLAA and identifies the appropriate disposition under 10 CFR 54.21 (c)(l). This information will be submitted by September 1, 2006. I declare under penalty of perjury that the foregoing is true and correct. Executed on March 30,2006. Site Vice President, Palisades Nuclear Plant Nuclear Management Company, LLC Enclosure CC Administrator, Region Ill, USNRC Project Manager, Palisades, USNRC Resident Inspector, Palisades, USNRC License Renewal Project Manager, Palisades, USNRC 27780 Blue Star Memorial Highway Covert, Michigan 49043-9530 Telephone: 269.764.2000 ENCLOSURE 1 NMC Responses to NRC Requests for Information Dated March 8,2006 (10 Pages)

Enclosure 1 Supplemental Responses to NRC Questions Relating to License Renewal NRC RAI 3.3-1 In LRA Sections 3.3 and 3.4, the applicant proposed to manage loss of material of carbon steellcast iron components internally exposed to raw waterlsteam using only the One-Time lnspection Program. The One-Time lnspection Program provides a means of verifying that an aging effect is either not occurring or progressing so slowly as to have a negligible effect on the intended function of the structure or component. Carbon steellcast iron is subject to significant corrosion under moisture. The staff requests the applicant to provide the justification for only using the One-Time lnspection Program. NMC Response to NRC RAI 3.3-1 For those cases where "Loss of Material - Selective Leaching" is the Aging Effect Requiring Management, the One Time lnspection Program is the correct program, and it need not be coupled with another program. As indicated in the License Renewal Application Section B2.1 .I3 on pages B B-107, the Palisades One-Time lnspection - Program contains the elements of the GALL program "Selective Leaching of Materials".

As stated under Conclusion on page B-106, "This program is consistent with NUREG- 1801,Section XI.M33, "Selective Leaching of Materials"." For other cases, however, NMC concurs that the One-Time lnspection Program should not be used by itself as an aging management program if aging is anticipated. While many of the items in Sections 3.3 and 3.4 have controlled internal environments that should preclude aging degradation, there are some items in these sections that are not subject to another aging management program. For completeness and clarity, therefore, the affected line items are revised to identify the applicable aging management program and/or credited activities, either as a replacement for, or in addition to, the One Time lnspection Program.

A listing of those carbon steel and cast iron line items in LRA Sections 3.3 and 3.4 which only cite One-Time lnspection is provided below with the appropriate changes:

I. In Table 3.3.2-5, on page 3-139, to the line item for "Drip Pans" of "Carbon Steel" in "Raw Water (Int)," the "One-Time lnspection Program" is hereby replaced by the "System Monitoring Program" to manage Loss of Material. The corresponding NUREG 1801 Volume 2, Table 1, and Notes entries are "VII.CI.1-a" and "3.3.1-15" and "C", respectively.

2. In Table 3.3.2-9, on page 3-163, the line item for "Heat Exchanger" of "Carbon Steel" in "Steam (Int)," was already revised to add the Water Chemistry Program in NMC letter to NRC dated 08/27/2005. See Question 39 in Enclosure 1 on page 45. This item is included for completeness only.

3. On page 3-201, the note 365 "Not Used" is hereby replaced with new note 365 to read, "Palisades will perform internal visual inspections of opportunity when maintenance provides such an opportunity." To assure that these inspections are implemented, applicable Palisades procedures will be enhanced to inspect and document the internal condition of applicable in-scope components when maintenance Enclosure 1 Supplemental Responses to NRC Questions Relating to License Renewal provides an opportunity. Applicable components are those that have an internal environment of water, are constructed of materials that are potentially susceptible to internal aging degradation in a wetted environment, but are not subject to another Aging Management Program (e.g., Water Chemistry, Open Cycle Cooling) that would manage the internal environment such that aging degradation of the internal surfaces would not be expected. 4. In Table 3.3.2-9, on page 3-168, to the line item for "Pipe and Fittings" of "Carbon Steel" in "Raw Water (Int)," additional note 365 is hereby added to Notes. 5. In Table 3.3.2-9, on page 3-168, the line item for "Pipe and FittingsJ1 of "Carbon Steel" in "Steam (Int)," was already revised to add the Water Chemistry Program in NMC letter to NRC dated 08/27/2005. See Question 39 in Enclosure 1 on page 45.

This item is included for completeness only. 6. In Table 3.3.2-9, on page 3-169, to the line item for "Traps (Steam)" of "Cast Iron" in "Steam (Int)," "Water Chemistry Program" is hereby added in addition to the current "One Time lnspection Program" to manage Loss of Material. The corresponding NUREG 1801 Volume 2 and Table 1 items are blank and the Notes entry is "390, 393, G." 7. In Table 3.3.2-9, on page 3-169, to the line item for "Traps (Steam)" of "Cast IronJ1 in "Raw Water (Int)," the environment is hereby changed to "Treated Water (Int)." The "Water Chemistry Program" is also added in addition to the current "One Time lnspection Program" to manage Loss of Material. The corresponding NUREG 1801 Volume 2 and Table 1 items are blank and the Notes entry is "390, 393, G." 8. In Table 3.3.2-9, on page 3-170, to the line item for "Valves and Dampers1' of "Carbon Steel1' in "Raw Water (Int)," the "Open Cycle Cooling Water Program" is hereby added to replace the current "One Time lnspection ProgramJ1 to manage Loss of Material.

The corresponding NUREG 1801 Volume 2 and Table 1 items are blank and the Notes entry is "395, G." 9. In Table 3.3.2-1 1, on page 3-174, to the line item for "Accumulators" of "Carbon Steel1' in "Raw Water (Int)", note 365 is hereby added with the existing Notes. 10. In Table 3.3.2-1 1, on page 3-175, to the line item for "Heat Exchangers" of "Carbon Steel" in "Steam (Int)," the "Water Chemistry Program" is hereby added in addition to the current "One Time lnspection Program" to manage Loss of Material. The corresponding NUREG 1801 Volume 2 and Table 1 items are blank, and the Notes entry is "331, J". 1 1. In Table 3.3.2-1 1, on page 3-1 76, to the line item for "Pipe and Fittings" of "Carbon Steel" in "Raw Water (Int)," note 365 is hereby added with the existing Notes.

Supplemental Responses to NRC Questions Relating to License Renewal 12. In Table 3.3.2-1 1, on page 3-177, to the line items for "Pumps" of "Carbon Steel" in "Raw Water (Ext)" and "Raw Water (Int)", note 365 is hereby added with the existing Notes. 13. In Table 3.3.2-1 1, on page 3-178, to the line item for "Valves and Dampers" of "Carbon Steel1' in "Raw Water (Int)", note 365 is hereby added with the existing Notes.

14. In Table 3.3.2-12, on page 3-180, to the line item for "Heat Exchanger" of "Carbon Steel" in "Raw Water (Int)," replace the current "One Time lnspection Program" with "Open Cycle Cooling Water Program1' to manage Loss of Material. The corresponding NUREG 1801 Volume 2, Table I, and Notes entries are "VII.CI .3-a" and "3.3.1-17", and "A, respectively.

15. In Table 3.3.2-15, on page 3-192, to the line item for "Accumulator" of "Carbon Steel" in "Raw Water (Int)", note 365 is hereby added with the existing Notes.

16. In Table 3.3.2-1 5, on page 3-1 93, to the line item for "Pipe and Fittings" of "Carbon - Steel" in "Raw Water (Int)", note 365 is hereby added with the existing Notes.

17. In Table 3.3.2-15, on page 3-193, to the line item for "Valves and Dampers" of "Carbon Steel" in "Raw Water (Int)," note 365 is hereby added with the existing Notes. 18. In Table 3.3.2-16, on page 3-1 94, to the line item for "Accumulator" of "Carbon Steel" in "Raw Water (Int)," note 365 is hereby added with the existing Notes.

19. In Table 3.3.2-16, on page 3-194, to the line item for "Heat Exchanger" of "Carbon Steel" in "Raw Water (Int)," note 365 is hereby added with the existing Notes.

20. In Table 3.3.2-16, on page 3-194, to the line item for "Heat Exchanger" of "Carbon Steel" in "Steam (Int)," the "Water Chemistry Program" is hereby added in addition to the current "One Time lnspection Program" to manage Loss of Material. The corresponding NUREG 1801 Volume 2 and Table 1 items are blank, and the Notes entry is J". 21. In Table 3.3.2-16, on page 3-195, to the line item for "Pipe and Fittings" of "Carbon Steel" in "Raw Water (Int)", note 365 is hereby added with the existing Notes.

22. In Table 3.3.2-16, on page 3-195, to the line item for "Pumps" of "Carbon Steel" in "Raw Water (Int)", note 365 is hereby added with the existing Notes. 23. In Table 3.3.2-16, on page 3-195, to the line item for "Valves and Dampers" of "Carbon Steel" in "Raw Water (Int)", note 365 is hereby added with the existing Notes.

24. On page 3-253, a new note 426 is hereby added, to read, "Palisades will perform internal visual inspections of opportunity when maintenance provides such an opportunity." To assure that these inspections are implemented, applicable Palisades procedures will be enhanced to inspect and document the internal condition of Enclosure 1 Supplemental Responses to NRC Questions Relating to License Renewal applicable in-scope components when maintenance provides an opportunity.

Applicable components are those that have an internal environment of water, are constructed of materials that are potentially susceptible to internal aging degradation in a wetted environment, but are not subject to the Water Chemistry, Open Cycle Cooling, Fire Protection, or another Aging Management Program that would manage the internal environment such that aging degradation of the internal surfaces would not be predicted.

25. In Table 3.4.2-1, on page 3-220, to the line item for "CST Heater Tubes and Tube Sheet" (as modified in response to RAI 2.3.4.1-2 in letter of 10/21/05) of "Carbon Steel" in "Steam (Ext)", for AERM "Loss of Material - Fretting", note 426 is hereby added with the existing Notes.

26. In Table 3.4.2-1, on page 3-221, to the line item for "Heat Exchanger" of "Carbon Steel" in "Steam (Int)," the "Water Chemistry Program" is hereby added in addition to the current "One Time lnspection Program1' to manage Loss of Material.

The corresponding NUREG 1801 Volume 2, Table 1, and Notes entries are "VIII.A.1-b", "3.4.1 -02", and "D", respectively.

27. In Table 3.4.2-2, on page 3-225, to the line item for "Heat Exchangers" of "Carbon Steel" in "Steam (Int)," the "Water Chemistry Program" is hereby added in addition to the current "One Time lnspection Program" to manage Loss of Material.

The NUREG 1801 Volume 2, Table 1, and Notes entries for both the One-Time lnspection and Water Chemistry Programs are "VI I I .C. 1 -b", "3.4.1 -02", and "DM, respectively.

28. In Table 3.4.2-3, on page 3-227, the line item for "Heat Exchangers" of "Carbon Steel" in "Raw Water (Int)" was already revised to incorporate the Open Cycle Cooling Water Program in NMC letter to NRC dated 08/27/2005.

See Question 44 in Enclosure 1 on page 51. This item is included for completeness only. 29. In Table 3.4.2-3, on page 3-232, the line item for "Valves and Dampers" of "Carbon Steel" in "Raw Water (Int)" was already revised to incorporate the Fire Protection and Open Cycle Cooling Water Programs in NMC letter to NRC dated 08/27/2005. See Question 44 in Enclosure 1 on page 51. This item is included for completeness only. 30. In Table 3.4.2-4, on page 3-237, to the line item for "Valves and Dampers" of "Cast IronJ' in "Steam (Int)", and AERM "Loss of Material - Selective Leaching," no change is required. The Palisades One Time lnspection Program contains the elements of the GALL program "Selective Leaching of Materials Program".

As indicated in the License Renewal Application, Page B-106, Conclusion, "This program is consistent with NUREG-1801,Section XI.M33, "Selective Leaching of Materials"." This item is included for completeness only. 31. In Table 3.4.2-5, on page 3-239, to the line item for "Blowers Fans.. ." of "Cast Iron" in "Steam (Int)," "Loss of Material - Selective Leaching," no change is required. The Palisades One Time lnspection Program contains the elements of the GALL program "Selective Leaching of Materials Program". As indicated in the License Renewal Enclosure 1 Supplemental Responses to NRC Questions Relating to License Renewal Application, Page B-106, Conclusion, "This program is consistent with NUREG-1 801,Section XI.M33, "Selective Leaching of Materials." This item is included for completeness only. 32. In Table 3.4.2-5, on page 3-241, to the line item for "Traps (Steam)" of "Carbon Steel" in "Raw Water (Int)", the environment is hereby changed to "Treated Water (Int)". The "Water Chemistry Program" is hereby added in addition to the current "One Time lnspection Program" to manage Loss of Material. The NUREG 1801 Volume 2, Table 1, and Notes entries for both the One Time lnspection and Water Chemistry Programs are "VIII.El .-b", "3.3.1-1 7", and C, respectively.

33. In Table 3.4.2-5, on page 3-242, to the line item for "Valves and Dampers" of "Cast Iron" in "Steam (Int)," and AERM "Loss of Material - Selective Leaching," no change is required.

The Palisades One Time lnspection Program contains the elements of the GALL program "Selective Leaching of Materials Program".

As indicated in the License Renewal Application, Page B-106, Conclusion, "This program is consistent with NUREG-1801,Section XI.M33, "Selective Leaching of Materials." This item is included - for completeness only. 34. In Table 3.4.2-6, on page 3-244, the line item for "Heat Exchanger" of "Carbon Steel" in "Steam (Int)," was already revised to add the Water Chemistry Program in NMC letter to NRC dated 08/27/2005. See Question 47 in Enclosure 1 on page 54. This item is included for completeness only. 35. In Table 3.4.2-7, on page 3-248, to the line item for "Heat Exchanger" of "Carbon Steel" in "Raw Water (Int)," the current "One Time lnspection Program" is hereby replaced with the "Open Cycle Cooling Water Program" to manage Loss of Material.

The corresponding NUREG 1801 Volume 2 and Table litems are unchanged, and Note "EM is changed to note "A. 36. In Table 3.4.2-7, on page 3-249, to the line item for "Pipe and Fittings" of "Carbon Steel", delete the "Raw Water (Int)" line item. To the existing "Treated Water (Int)" line item, the "Water Chemistry Program" is added in addition to the current "One Time lnspection Program" to manage Loss of Material.

The NUREG 1801 Volume 2, Table 1, and Notes entries for both the Water Chemistry and One-Time lnspection Programs are "VIII.E.1-b", "3.4.1 .0211, and "A, respectively.

37. In Table 3.4.2-7, on page 3-249, to the line item for "Pipe and Fittings" of "Carbon Steel" in "Steam (Int)," the "Water Chemistry Program" is hereby added in addition to the current "One Time lnspection Program" to manage Loss of Material.

The NUREG 1801 Volume 2, Table 1, and Notes entries for both the Water Chemistry and One-Time lnspection Programs are "V1II.A. 1 -bl', "3.4.1-02", and "A, respectively.

38. In Table 3.4.2-7, on page 3-250, to the line item for "Valves and Dampers" of "Carbon Steel" delete the "Raw Water (Int)" line item. To the existing "Treated Water (Int)" line item, the "Water Chemistry Program" is hereby added in addition to the current "One Time lnspection Program" to manage Loss of Material.

The NUREG 1801 Volume Supplemental Responses to NRC Questions Relating to License Renewal 2, Table 1, and Notes entries for both the Water Chemistry and One-Time lnspection Programs are "V1II.E. 1-b", "3.4.1 -02", and "A, respectively.

39. In Table 3.4.2-7, on page 3-250, to the line item for "Valves and Dampers" of "Carbon Steel" in "Steam (Int)," the "Water Chemistry Program" is hereby added in addition to the current "One Time lnspection Program" to manage Loss of Material.

The NUREG 1801 Volume 2, Table 1, and Notes entries for both the Water Chemistry and One-Time lnspection Programs are "VIII.A.1-by', "3.4.1-02", and "A, respectively.

40. To LRA Appendix A, a new section A2.22 is hereby added to read as follows, "A2.22 Inspections of Opportunity for Internal Surfaces of Selected Components Internal surfaces of selected systems and components which are exposed during periodic system and component surveillances, or during the performance of maintenance activities, are subject to visual inspections of opportunity. These inspections are applicable to components in-scope for license renewal that have an internal environment of water, are constructed of materials that are potentially susceptible to internal aging degradation in a wetted environment, but are not subject to an Aging Management Program (e.g., Water Chemistry) that would manage the internal environment such that aging degradation of the internal surfaces would not be expected. Visual inspections are performed to assure that existing environmental conditions are not causing material degradation that could result in a loss of a component intended function. lnspection activities are performed by qualified personnel looking for corrosion (General, Pitting, Crevice, MIC) and fouling. Degraded conditions are documented in the Corrective Action Program and evaluated for acceptability, repair, or replacement.

Supplemental Responses to NRC Questions Relating to License Renewal NRC RAI 3.3-2 In LRA Sections 3.3 and 3.4, the applicant proposed to manage loss of material of metal components exposed to oil environment using the One-Time lnspection Program. The generic aging lessons learned (GALL) report recommended that loss of material and reduction of heat transfer aging effects are to be managed by a plant specific or lubricatinglfuel oil analysis AMP along with the One-Time lnspection Program to ensure the effectiveness of the AMP. The staff requests the applicant to provide the following:

1. The justification of methods used to ensure the oil remains free of contaminants, which might degrade the components.

2. The description of preventive maintenance to ensure that the reduction of heat transfer function does not reach unacceptable levels for components performing heat transfer functions.

NMC Response to NRC RAI 3.3-2 NMC concurs that the One-Time lnspection Program should not be used by itself as an aging management program for the various materials in oil environments if aging is anticipated. In the context of this question, however, routine oil sampling and analysis activities will maintain the oil system contaminants (primarily water and particulates) within acceptable limits, thereby preserving an environment that is not conducive to loss of material, cracking, or reduction of heat transfer. For completeness, therefore, the affected line items are revised to indicate that oil sampling and analysis activities would maintain the environments such that aging would not be expected, and One Time lnspection is used for confirmation that significant aging is not occurring. A listing of the changes to the affected LRA line items in Sections 3.3 and 3.4, which only cite One- Time lnspection for the oil environment, is provided below. 1. On LRA Page 3-1 98, Note 31 1 is hereby changed from "Not Used" to "The Oil environment for this component is managed by periodic oil sampling and analysis activities, and the effectiveness of these activities will be verified by a one-time inspection." 2. In Table 3.3.2-1 on page 3-1 18, for the line item "Oil Cooler Shell" with an "Oil (Int)" environment, note 31 1 is hereby added with the existing Notes. 3. In Table 3.3.2-1 on page 3-120, for the line item "Tubing - CVC Oil", note 31 1 is hereby added with the existing Notes.

4. In Table 3.3.2-4 on page 3-132, for the line item "FiIterslStrainers" with an "Oil (Int)" environment, note 31 1 is hereby added with the existing Notes.

Enclosure 1 Supplemental Responses to NRC Questions Relating to License Renewal

5. In Table 3.3.2-4 on page 3-135, for the line item "Valves

& Dampers" with an "Oil" environment, note 31 1 is hereby added with the existing Notes for both "Cracking" and "Loss of Material". 6. In Table 3.3.2-6 on page 3-142, for the line item "Cooler" with "Oil (Ext)" environment (for both Fluid Pressure Boundary and Heat Transfer Intended Functions), note 31 1 is hereby added with the existing Notes entries (two places) for "Heat Transfer Degradation", and with the existing Notes entries (two places) for "Loss of Material" 7. In Table 3.3.2-6 on page 3-142, for the line item "Cooler" with "Oil (Int)" environment, note 31 1 is hereby added with the existing Notes. 8. In Table 3.3.2-6, on page 3-143, for the line item "Heat Exchangers" with an "Oil (Int)" environment, note 31 1 is hereby added with the existing Notes. 9. In Table 3.3.2-6, on page 3-144, for the line item "Heat Exchangers" with an "Oil (Ext)" environment, note 31 1 is hereby added with the existing Notes for "Heat Transfer - Degradation", with the existing Notes for "Loss of Material - Selective Leaching", and with the existing Notes for "Loss of Material".

10. In Table 3.3.2-6, on page 3-145, for the line item "Heat Exchangers" with an "Oil (Ext)" environment, note 31 1 is hereby added with the existing Notes for "Heat Transfer Degradation", with the existing Notes for "Loss of Material - Selective Leaching", and with the existing Notes "Loss of Material".

I I. In Table 3.3.2-6, on page 3-146, for the line item "Heaters, Electric" with an "Oil (Int)" environment, note 31 1 is hereby added with the existing Notes. 12. On LRA page 3-198, Note 312, change "Not used" to "This is a component in the Primary Coolant Pump oil collection system which is designed to collect oil leakage from a Primary Coolant Pump motor. It is being age managed for Fluid Pressure Boundary even though the system is vented to the containment atmosphere, and would only experience a small static head pressure. Any oil entering the tank from a Primary Coolant Pump oil leak would be oil that is subject to sampling and analysis. Therefore, Palisades does not expect significant age-related degradation of these components, and will perform a one-time inspection to verify that this is the case." 13. In Table 3.3.2-7, on page 3-153, for the line item "Accumulators" with an "Oil (Int)" environment, note 312 is hereby added with the existing Notes.

14. In Table 3.3.2-7, on page 3-155, for the line item "Pipe

& Fittings" with an "Oil (Int)" environment, note 312 is hereby added with the existing Notes. 15. On LRA Page 3-199, Note 309, change "Not Used" to "This is a component in the Control Room Air Conditioning Refrigeration Unit. The environment is refrigerant with entrained oil. There is no moisture in circulation with the oillrefrigerant, and, therefore, Supplemental Responses to NRC Questions Relating to License Renewal no degradation is expected. A one-time inspection will be performed to verify that this is the case only if a refrigeration unit is required to be opened for maintenance." 16. In Table 3.3.2-9, on page 3-162, for the line item "FiltersIStrainers", note 309 is hereby added with the existing Notes for the "Oil (Int) environment.

17. In Table 3.3.2-12, on page 3-180, for the line item "Heat Exchanger" with an "Oil (Int)" environment, note 31 1 is hereby added with the existing Notes.

18. On LRA Page 3-253, add a new Note 425 to read, "The Oil environment for this component is managed by periodic oil sampling and analysis activities, and the effectiveness of these activities will be verified by a one-time inspection." 19. In Table 3.4.2-3, on page 3-227, for the line item "Accumulators" with an "Oil (Int)" environment, note 425 is hereby added with the existing Notes.

20. In Table 3.4.2-3, on page 3-227, for the line item "FiltersIStrainers" with an "Oil (Int) - environment, note 425 is hereby added with the existing Notes.

21. In Table 3.4.2-3, on page 3-227, for the line item "Heat Exchangers" with an "Oil (Int) environment, note 425 is hereby added with the existing Notes.

22. In Table 3.4.2-3, on page 3-229, for the line item "Pipe

& Fittings" with an "Oil (Int) environment, note 425 is hereby added with the existing Notes. 23. In Table 3.4.2-3, on page 3-230, for the line item "Pipe & Fittings" with an "Oil (Int) environment, note 425 is hereby added with the existing Notes.

24. In Table 3.4.2-3, on page 3-231, for the line item "Pumps" with an "Oil (Int)" environment, note 425 is hereby added with the existing Notes. 25. In Table 3.4.2-7, on page 3-248, for the line item "Accumulators" with an "Oil (Int)" environment, note 425 is hereby added with the existing Notes for Loss of Material in Carbon steel, and with the existing Notes for Loss of Material in Stainless steel.

26. In Table 3.4.2-7, on page 3-248, for the line item "FiltersIStrainers" with an Oil (Int)" environment, note 425 is hereby added with the existing Notes.

27. In Table 3.4.2-7, on page 3-248, for the line item "Heat Exchangers" with an "Oil (Int)" environment, note 425 is hereby added with the existing Notes.

28. In Table 3.4.2-7, on page 3-249, for the line item "Pipe & Fittings" with an "Oil (Int)" environment, note 425 is hereby added with the existing Notes for Loss of Material in Carbon steel, and with the existing Notes for Loss of Material in Stainless steel.

Enclosure 1 Supplemental Responses to NRC Questions Relating to License Renewal 29. In Table 3.4.2-7, on page 3-249, for the line item "Pumps" with an "Oil (Int) environment, note 425 is hereby added with the existing Notes for Loss of Material in Carbon steel, and with the existing Notes for Loss of Material in Cast Iron. 30. In Table 3.4.2-7, on page 3-250, for the line item "Valves

& Dampers" with an "Oil (Int)" environment, note 425 is hereby added with the existing Notes.

31. To LRA Appendix A, a new section A2.23 that addresses future oil sampling and analysis activities is hereby added to read as follows, "A2.23 Oil Sampling and Analysis For selected components, in-scope for license renewal, that have an internal environment of oil, and are constructed of materials that are potentially susceptible to internal aging degradation in that environment, the oil shall be subject to periodic sampling and analysis.

The purpose of these activities is to ensure that oil system contaminants (primarily water - and particulates) are maintained within acceptable limits, thereby preserving an environment that is not conducive to loss of material or reduction of heat transfer. Associated activities include (a) determination of appropriate analysis to be performed, (b) frequency of analysis, (c) acceptance criteria, (d) trending of results, and (e) corrective actions, if required. These activities ensure that the lubricating oil environment of these components is maintained such that water and contaminants are minimized."

Enclosure 2 Supplemental Responses to NRC Questions Relating to License Renewal Enclosure 2 Supplemental Responses to NRC Questions Relating to License Renewal NRC Potential Open ltem B.2.1.20-I (c) The LRA AMR Tables credit the System Monitoring Program for managing external surfaces of elastomers, but elastomers are not specifically addressed in the System Monitoring program.

In RAI B2.1.20-l(b), the applicant was requested to clarify if elastomers are within scope of the System Monitoring Program and, if so, consider the unique aging degradation characteristics of elastomers in the specified environment and include a discussion of elastomers within each element of the program.

By letter dated July 25, 2005, the applicant clarified that there are no elastomers in mechanical systems that are required to be managed by an Aging Management Program. This response is evaluated below under RAI B2.1.20-1 (c). Considering the limited shelf life and service life of elastomers for the specified environment, in RAI B.2.1.20-l(c), the applicant was requested to clarify if elastomers meet the definition of long-lived components within scope of license renewal. By letter dated July 25, 2005, the applicant responded that NMC has determined that the elastomers listed in the Heating Ventilation and Air Conditioning (HVAC) system and the - Service Water System AMR Tables of the LRA are not long-lived components that require aging management. Therefore, the applicant concluded, there are no elastomers in mechanical systems that are required to be managed by an Aging Management Program and the line items for elastomers in Tables 2.3.3-9, 3.3.2-9 and 3.3.2-12 and Sections 3.3.2.1-9 and 3.3.2.1-12 should be deleted. The applicant clarified that, based on this determination, NMC will enhance the preventive maintenance program to periodically inspect and replace as necessary the expansion jointslflexible connections in the HVAC system and Service Water System that are within scope of license renewal. The staff was concerned that, although these passive components do not require an aging management program if they are not long-lived components, the Part 54.21 rule requires an IPA for passive components unless they are subject to replacement based on a qualified life or specified time period. Therefore, the applicant must either, (1) clarify that these components are not in scope because they will be replaced based on a qualified life or specified time period, or (2) clarify that these passive components are considered in scope because they are long-lived and will be periodically inspected by an aging management program such as the system monitoring program or preventive maintenance program. The program that manages the elastomers should include appropriate criteria for inspecting the elastomers. In a conference call with the applicant on September 14, 2005, it was agreed that this concern is considered unresolved and deferred.

This is identified as Open ltem B.2.1.20-I (c). Except for the above unresolved items, the staff finds the scope of the program to be comprehensive and acceptable because it includes the components that credit this program, as identified in the AMR tables. NMC Res,ponse to Potential Open ltem B2.1.20-l(c)

NMC responded to NRC follow up questions on previous responses to RAI B2.1.20- I (c), and also provided updated responses to the related RAls B2.1.20-l(b) and 82.1.20-2(b), in a letter dated November 18, 2005. The updated response to RAI B2.1.20-l(c) revised the original response by stating that mechanical elastomers in the Supplemental Responses to NRC Questions Relating to License Renewal Service Water System (SWS) and the Heating, Ventilating and Air Conditioning (VAS) System are included in the scope of the LRA. It went on to state that the SWS elastomers are not long lived and are replaced on a periodic basis. The VAS elastomers are long lived, and are age managed as described in the LRA, consistent with the GALL. The updated response to RAI B2.1.20-2(b) clarified that "Visual inspections will detect cracking resulting from changes in material properties such as loss of flexibility and embrittlement. Physical manipulation during the visual inspection will verify flexibility of the elastomers." During a meeting on February 14, 2006, the NRC indicated that these responses should be supplemented further to identify relevant OE or standards related to assessment of elastomers through physical manipulation, provide references to SERs of previous license renewal applicants that used similar physical manipulation strategies to manage elastomer aging, and provide a revised FSAR description of the System Monitoring Program that indicates that is also used to manage aging of elastomers. Visual inspections will detect cracking resulting from changes in material properties such - as loss of flexibility and embrittlement. Physical manipulation during the visual inspection will verify flexibility of the elastomers and identify deterioration of rubber components by feel (soft and spongy, brittle, tacky, etc). Palisades has successfully utilized physical manipulation for some time to inspect elastomers associated with water tight barriers and secondary side piping expansion joints, including expansion joints for the condenser water boxes, cooling tower pumps, cooling tower bypasses, and condensate pumps. The procedures use a combination of visual inspection and manipulation to determine the condition of the elastomers.

By using both visual indications and feel, an inspector can determine if an elastomer shows signs of degradation by cracking or flaking, by being hard and brittle, or by being soft, spongy, or tacky. In the updated response to RAI B2.1.20-I (b), under Detection of Aging Effects, NMC stated, "For elastomers, visual inspections will detect loss of material due to abrasionlwear and cracking resulting from changes in material properties such as loss of flexibility and embrittlement. Physical manipulation during the visual inspection will verify flexibility and lack of hardening of the elastomers." This is similar to the position accepted by the NRC in the SER for DC Cook plant's license renewal, NUREG 1831, on page 3-296, Response to RAI 3.3.3-2.

The SER states, "In its response dated September 2, 2004, the applicant stated that it will verify the flexibility of the hoses through physical manipulation of the hose during visual inspection, thereby enhancing the inspector's ability to sense (both visually and through touch) a change in material properties that could affect the performance of the elastomers." The SER goes on to conclude, "On the basis of its review of the applicant's response to RAI 3.3.3-2, the staff finds that the applicant has demonstrated that it will adequately manage change in material properties of flexible hoses resulting from hardening and flexibility in the EDG system so that the intended function will be consistent with the CLB during the period of extended operation, as required by 10 CFR 54.21 (a)(3)."

Supplemental Responses to NRC Questions Relating to License Renewal Another precedent is found in the SER for license renewal of Millstone 2 and 3. Section 3.0.3.3.2, General Condition Monitoring, on page 3-105, states, "The general condition monitoring program also credits visual inspection for the detection of changes in material properties in elastomers in the ventilation systems and in support members. During the audit and review, it was not clear to the staff how visual inspections would be used to monitor this aging effect. In a subsequent staff visit to the plant, the applicant stated that the change of material properties for these elastomers components is visually observable by evidence of cracking and crazing, discoloration, distortion, evidence of swelling, tackiness, evaluation of resilience and indentation recovery, etc." It is apparent from this discussion of tackiness, resilience, etc., that the visual inspection included touching and manipulating the elastomer material. The SER goes on to state, "The applicant stated in the LRA that the procedures and training for personnel performing general condition monitoring inspections and walkdowns will be enhanced to identify the requirements for the inspection of aging effects. ... Based on the review of the LRA commitment and document change request, the staff concurs that change in material properties can be visually observed." To reflect the management of elastomers in the FSAR description of the System Monitoring Program, LRA Section A2.20 is hereby revised to add a discussion of elastomers. The revised section reads as follows: "A2.20 System Monitoring Program The System Monitoring Program manages aging effects for normally accessible, external surfaces of piping, tanks, and other components and equipment within the scope of License Renewal. These aging effects are managed through visual inspection and monitoring of external surfaces for leakage and evidence of material degradation.

The program relies upon periodic system walkdowns to monitor degradation of the protective paint or coating, andlor the exterior steel surface area (if no paint or coatings exist, or if the existing protective paint and coatings are degraded to a point whereby the exterior steel surface is exposed). Palisades does not take credit for any above ground coating or paint for mitigating corrosion even though the tanks may be painted or coated. However, inspections of the above ground coating or paint will provide an indication of the condition of the material underneath the coating or paint. The System Monitoring Program will also manage the aging effects of elastomers. Visual inspections will detect loss of material due to abrasionlwear and cracking resulting from changes in material properties such as loss of flexibility and embrittlement.

In addition, physical manipulation during the visual inspection will verify flexibility and lack of hardening of the elastomers. "

Enclosure 2 Supplemental Responses to NRC Questions Relating to License Renewal NRC Potential Open ltem 4.3.12 - Absence of a TLAA for ASME Ill Class 1 HELB Locations and Leak-Before-Break Analyses Based on Fatigue Usage Factor The staff reviewed the Palisades FSAR, Section 5.6.3, "Criteria Used to Define Breaks," and Subsection 5.6.3.1, "ASME Section Ill, Class 1 Piping." This subsection shows the requirement that pipe breaks be postulated at all intermediate locations throughout a piping system where the CUF exceeds 0.1 0. This criterion is also stated in NRC Generic Letter 87-1 1, which is referenced in the FSAR. The applicant stated that HELB locations in ASME Section Ill Class 1 piping at Palisades are not dependent on aging factors. The staff interprets this statement as indicating that this criterion has not been considered in the postulation of intermediate HELB in Palisades ASME Section Ill Class 1 piping. The applicant has not provided any basis for this statement. The staff finds that the applicant has not provided a reasonable basis for concluding that the HELB analyses at Palisades do not involve TLAAs. This is therefore an Open Item. NMC Response to Potential Open ltem 4.3.12 - Absence of a TLAA for.ASME Ill Class 1 HELB Locations and Leak-Before-Break Analyses Based on Fatigue Usage Factor Section 4.3.12 of the Palisades LRA states: "4.3.12 Absence of a TLAA for ASME Ill Class 1 HELB Locations and Leak-Before-Break Analyses Based on Fatigue Usage Factor Review of the Palisades licensing basis and the associated HELB reports revealed that selected break locations, either inside or outside containment, were not dependent on aging factors. Therefore, HELB analyses at Palisades are not TLAAs." This summary was based on an evaluation of the methodology used to perform High Energy Line Break (HELB) analyses under Palisades' Current Licensing Bases (CLB), as summarized in the Palisades FSAR. Additional information relevant to this subject can be found in FSAR Section 5.6, and in LRA Section 4.3.1 (pages 4-16 through 18), Table 4.3.1-2 (page 4-21), and Section 4.3.8 (pages 4-29 through 31). Also see Section 4.3.1 3 (pages 4-36 through

38) for additional discussion of which piping has been analyzed for fatigue. When the Palisades Plant was designed, ASME Boiler & Pressure Vessel Code Section Ill did not address piping.

FSAR Section 5.2 discusses the plant design classes of the Palisades CLB that exist in lieu of ASME design classes 1, 2 and 3. Most piping was designed and installed under ANSI B31 .I regardless of function. B31 .I did not require piping analyses for fatigue usage. As described in FSAR Section 5.6.7, Palisades' HELB analyses were not required as part of the original design, and were performed after the plant was licensed to operate. As described in FSAR Section 5.6.3.1, the HELB analysis criteria that governed break location selection in ASME Section Ill, Class 1, piping included a provision based on CUF where fatigue analyses had been done.

Enclosure 2 Supplemental Responses to NRC Questions Relating to License Renewal However, that criterion was not applicable to most high energy lines in the plant since they were not designed to ASME Section Ill, and fatigue of piping had not been analyzed under the B31 .I design. ASME class designators have since been assigned to piping and components based on function for Section XI inservice and preservice (post-repair or replacement) inspection purposes only. These designations are not applicable to piping design analyses, which are governed by the design requirements in FSAR Sections 5.2 and 5.7. Analyses of HELB Outside Containment In December 1972, the NRC initially raised a concern for the dynamic effects of pipe ruptures and sent letters to all power reactor licensees requesting an analysis of the effects of postulated failures of high energy lines outside of containment.

In response, Consumers Power Co (CPCo) submitted Special Report No. 6 (SR-6). NRC letters of August 7, 1973 and October 9, 1973 to CPCo approved the original outside containment HELB evaluation program, including facility modifications and the augmented inservice inspection of selected locations for which modifications were impractical. The subject of HELBs outside of containment was further evaluated in 1981 and 1982 as part of the Nuclear Regulatory Commission's (NRC) Systematic Evaluation Program (SEP). CPCo submitted a summary document for NRC review of this topic. This evaluation compared the analysis and criteria used in SR-6 and modifications (mainly to pipe supports) made from 1979 through 1981 pursuant to IE Bulletin 79-14 against then-current methods and criteria. The result was that CPCols criteria for postulating pipe breaks and its method for evaluating postulated breaks in high energy piping outside containment are, in general, in accordance with (then) currently accepted standards.

Analyses of HELB Inside Containment In January 1979, the NRC informed CPCo that their review of the Palisades facility docketed material had not revealed sufficient information for a technical evaluation of the Systematic Evaluation program (SEP) Topic Ill-5.A on the effects of pipe breaks inside containment. CPCo was requested to provide additional data to allow the NRC to evaluate the Palisades design versus current criteria (circa 1979).

In that letter, the NRC included a position with approaches appropriate for postulating breaks in high energy piping systems (either pressure greater than 275 psig or temperature greater then 200°F). The approved approaches included

1) Mechanistic, or

2) Effects Oriented methods for selection of break locations. The NRC further stated that combinations of these approaches could be utilized if justified. The NRC later provided additional guidance .for evaluation of pipe breaks. Effects Oriented Approach In the Effects-Oriented Approach, pipe breaks in each run of a high energy piping system are postulated at the following locations:

Enclosure 2 Supplemental Responses to NRC Questions Relating to License Renewal 1. At the terminal ends of the run; and 2. At intermediate locations chosen to produce effects in accordance with the following:

a. A longitudinal pipe break at the point which produces the greatest jet impingement loading on each component of each essential system, and

b. A circumferential pipe break at the point which produces the greatest pipe whip loading on each component of each essential system. The philosophy of the Effects Oriented Approach is to predict worst case conditions in lieu of performing analyses to determine the most likely break locations. Each structure, system, component and power supply which must function - to mitigate the effects of pipe break and to safely shutdown the plant is examined to determine its susceptibility to the effects of the postulated breaks in high energy piping systems. Breaks are postulated at any location in the high energy piping that can cause an interaction, regardless of weld locations, etc.

CPCo Analyses CPCo outlined the program for the Palisades SEP analysis of pipe breaks within the containment building into the following four phases: Phase One consisted of the July, 1979 meeting between CPCo, its consultant, EDS Nuclear, and the NRC wherein the subject of Pipe Breaks Inside Containment for the Palisades Plant was discussed and the program for resolving this topic was presented. This meeting confirmed the acceptability of the plan for the balance of the studies. Phase Two work consisted of reviewing the design of the original five high energy systems installed inside containment at that time against the NRC SEP criteria for break postulation, developing specific damage study criteria, and completing the lists of potential high energy line break (HELB) interactions derived from an Effects Oriented Approach. The Effects Oriented Approach essentially assumed pipe breaks could occur at any location within high energy piping. Phase Two work was completed in early 1980. The Phase Three work, which was completed in April 1981, consisted of performing analyses required to assess the effects of the potential interactions identified in Phase Two. Phase Three was chiefly concerned with establishing pipe rupture and the jet impingement loadings, and determining the structural adequacy of the targets in response to these loadings, following specific procedures developed for HELB inside containment.

Following these analyses, Supplemental Responses to NRC Questions Relating to License Renewal an evaluation of the damage potential to essential plant systems from the high energy line breaks was performed. The purpose of this evaluation was to review and resolve, to the extent practical, the outstanding interactions. The work completed in the above three phases identified and resolved over 1000 interactions. However, over 200 interactions were not resolved by application of conservative engineering analysis in Phase Three.

The NRC accepted the Phase Three inside-containment HELB selection of bounding interactions and partial resolution of interactions in a draft SER, but requested additional informationlanalyses to close out the remaining issues.

Phase Four work consisted of more detailed evaluation of the remaining unresolved interactions.

Phase Four evaluations applied more refined analysis techniques to resolve the remaining potential break interactions. The refinements included limiting postulated break points to structural discontinuities (welds, and fittings), selected application of the mechanistic approach (based on calculated stress levels) for break postulation, detailed structural analysis calculations, and the application of leak-before-break (LBB) fracture mechanics.

The inside-containment HELB evaluations performed up to this point (through Phase Four completion) were accepted by the NRC in the initial revision and supplement to the Integrated Plant Safety Assessment Report (IPSAR) (NUREG 0820) for the Palisades SEP. All but two potential break interactions were considered acceptable. The remaining two unresolved interactions involved postulated breaks in the charging and letdown lines which might interact with steam generator pressure and level instrument lines. Alternatives considered for resolution of these two letdown and charging line interactions included the possibility of adding shielding.

However, CPCo performed mechanistic stress calculations for the letdown and charging lines which demonstrated that the two unresolved postulated breaks could be eliminated in accordance with the NRC-approved mechanistic criteria. The letdown and charging linelsteam generator pressure and level instrument line interactions were thereby removed from the overall list of possible break interactions inside containment. The NRC issued an SER in 1987, accepting the elimination of these two postulated breaks on the letdown and charging lines. The Mechanistic Approach selects line break locations based on either piping stress locations that exceed 2.4 S, or a CUF that exceeds 0.1. Where fatigue usage factors were available (Primary Coolant System hot and cold legs), they had been calculated based on the enveloped stress ranges for representative locations in each of a typical hot leg and cold leg.

Since the fatigue calculations were not location-specific, the CUF criteria could not be used with the Mechanistic Approach to determine the line break locations in the PCS. Therefore, only piping stress criteria, and not CUF, were available for use in the Mechanistic Approach for determining Palisades' line break locations.

In summary, with the exception of limited portions of selected high energy piping, which were analyzed using a Mechanistic Approach for HELB, all high-energy systems were Enclosure 2 Supplemental Responses to NRC Questions Relating to License Renewal analyzed under the Effects Oriented Approach.

The Effects Oriented Approach does not use fatigue or stress to determine line break locations.

Conclusion In summary, the Palisades HELB analysis methodology, as described in the FSAR, included one criterion for selection of break locations in ASME Section Ill Class 1 piping based on CUF (where analyzed), among others.

In practice, as discussed in FSAR Section 5.6.7, however, Palisades break locations were postulated using other selection criteria, and the CUF criterion was not used. The approaches to Palisades' HELB analyses contained in the Palisades CLB are summarized below:

Inside Containment:

HELB locations were determined from the Effects Oriented Approach for all high-energy piping, except for a portion of the Primary Coolant System hot leg and the cold leg where pipe stress criteria of the Mechanistic Approach were used. HELB locations were not determined based on a TLAA. Outside Containment: The Effects Oriented Approach was used. HELB locations were not determined based on a TLAA. Leak-Before-Break: Leak-before-break analyses at 13 locations inside containment were done to confirm that the effect of breaks are limited, and are not time-dependent. Therefore, as stated in the LRA, the selected break locations for Palisades HELB analyses, either inside or outside containment, were not dependent on time- dependent aging factors such as CUF. Therefore, HELB analyses at Palisades are not TLAAs.

Enclosure 2 Supplemental Responses to NRC Questions Relating to License Renewal NRC Potential Open ltem 4.3.12.3 FSAR Supplement The applicant has not provided an FSAR supplement. Based on a review of the FSAR, the staff concludes that the applicant needs to provide a supplement to the FSAR providing the basis for not postulating HELB in ASME Section Ill Class 1 piping, in accordance with the CUF requirement stated in FSAR Section 5.6.3.1 and NRC GL 87- 11. This is therefore an Open Item.

NMC Response to NRC Potential Open ltem 4.3.12.3 FSAR Supplement Since this item is not a TLAA as discussed above, an FSAR supplement is not applicable.

Enclosure 2 Supplemental Responses to NRC Questions Relating to License Renewal NRC Question Regarding Thermal Sleeves A question was raised about NMC's response to RAI 3.1-1 in the November 18, 2005 letter. The response removed cracking as an applicable aging effect for thermal sleeves. NMC was requested to provide additional justification why cracking is not applicable to thermal sleeves in general, and Alloy 600 thermal sleeves in particular, because this material is subject to PWSCC. NMC Response to NRC Question Regarding Thermal Sleeves The elimination of the cracking aging effect for thermal sleeves in the Primary Coolant System, that was documented in the November 18,2005 letter, was based on the low applied stress conditions of the thermal sleeves. For Stress Corrosion Cracking (SCC) or Primary Water Stress Corrosion Cracking (PWSCC) to occur, a combination of high stress, a corrosive environment, and a susceptible material is required. There is no pressure stress since the thermal sleeves are not a pressure boundary component and - have the same pressure on both sides of the sleeves. Similarly, the physical configuration of the thermal sleeves permits unrestricted axial growth and the relatively thin walls of the sleeves precludes significant through-wall stresses. Thus, thermal stresses are minimal. However, it is acknowledged that any residual stresses resulting from the expansion process used for securing the sleeves to the nozzles can not be quantified. Therefore, for license renewal, cracking due to SCC and PWSCC will conservatively be included as an applicable aging effect for thermal sleeves installed in the Primary Coolant System. Therefore, the cracking aging effects for LRA Table 3.1.2-1 line items "Stainless Steel Thermal Sleeves" on page 3-37 and "Alloy 600 Thermal Sleeves" on page 3-43 are reinstated as originally submitted in the LRA. The revisions to these line items that removed the cracking aging effects, made in Enclosure 3 (pages 6 & 7) of the NMC letter to NRC dated 1111 8/05, are hereby rescinded. The loss of material aging effects that were added in the 11/18/05 letter remain valid. These tables indicate that "Stainless Steel Thermal Sleeves" are age managed by the ASME Section XI IS1 Program and the Water Chemistry Program. The "Alloy 600 Thermal Sleeves" are being age managed by the Alloy 600 Program and the Water Chemistry Program. Note that the thermal sleeves are inaccessible for direct inspection; however, the results of the ASME Section XI IS1 and Alloy 600 program inspections on the adjacent nozzle and safe end welds are considered conservatively representative (given the higher applied stress conditions) of the condition of the thermal sleeves. Therefore, the Water Chemistry Program, coupled with inspections under ASME Section XI and Alloy 600 Programs, are sufficient to manage potential aging effects due to cracking on the sleeves without a need for direct inspection of the sleeves. The conclusion that direct inspection of thermal sleeves is not necessary to manage aging was approved by NRC in the SER for license renewal of the DC Cook plant (NUREG 1831) on pages 3-197 and 3-198. In the staff's evaluation, the SER states, "... the applicant adopted only the Water Chemistry Control and Alloy 600 Aging Enclosure 2 Supplemental Responses to NRC Questions Relating to License Renewal Management Programs to manage cracking in pressurizer surge and spray nozzle thermal sleeves under a borated water environment. Not using the Inservice Inspection Program recommended for GALL line item IV.C2.5-k for thermal sleeves is acceptable because the surge and spray nozzle thermal sleeves, which are mechanically connected to or welded to the safe end of the nozzles, are inaccessible from outside of the nozzles for inspections.

Further, the ASME code does not have inspection requirements for the pressurizer surge and spray nozzle thermal sleeves. Therefore, the staff concludes that using only the Water Chemistry control and Alloy 600 Aging management Programs to manage cracking in surge and spray nozzle thermal sleeves is acceptable."

Enclosure 2 Supplemental Responses to NRC Questions Relating to License Renewal NRC Question Regarding Alloy 600 Program The January 13, 2006 response to RAI 4.7.2-1 is confusing to the reviewer.

The program at issue is the Alloy 600 program, which monitors associated nozzles for PWSCC. The LRA talks about a 1995 report that has since been superseded by EPRl MRP work. In response to the RAI question about this report, Palisades responded by discussing fatigue analysis work completed since 1995. The fatigue analysis report does not appear relevant to the question about Alloy 600 monitoring for PWSCC. In addition the reviewer sought confirmation that the current inspection intervals for the two locations in Table 4.7.2-1 with less than a 40 year lifetime will be maintained into the extended operating period.

NMC Response to NRC Question Regarding Alloy 600 Program The discussion provided in the paragraph, "In 2004, the Combustion Engineering Owners Group

.... design basis values." was intended to indicate that later analyses, using updated references, have validated the adequacy of the information provided in Table 4.7.2-1. As written, however, the paragraph was unclear. Accordingly, this paragraph is hereby replaced in its entirety with the following: "As noted by the reviewer, the fracture mechanics summary in Table 4.7.2-1 of the license renewal application was based on a 1995 report, "Fracture Mechanics Assessment of Palisades Alloy 600 Components." Recent analyses, however, have been based on updated references that reflect advances in the industry. The discussion of cycle-dependent aspects of the current bounding fracture mechanics analyses, beginning on page 4-60 of the LRA, summarized the conclusion drawn from updated information that is based on the later references.

As noted, the current bounding analysis is based on WCAP-15973-P, Rev.1, "Low-Alloy Steel Component Corrosion Analysis Supporting Small-Diameter Alloy 6001690 Nozzle RepairlReplacement Programs (May 2004), and Westinghouse Calculation Note CN-CI- 02-71! Rev.1, "Summary of Fatigue Crack Growth Evaluation Associated with Small Diameter Nozzles in CEOG Plants." These later analyses confirmed that the Palisades cycle-dependent information developed in the earlier analyses and reported in the table remain valid. The summary disposition at the bottom of LRA page 4-60 reads, "The Palisades plant-specific bounding fracture mechanics analysis demonstrates the validity of the cycle-dependent aspects of the generic bounding fracture mechanics analysis (WCAP-15973-P) by demonstrating that the plant-specific load and thermal events are within those assumed by the generic bounding analysis.

The basis for the safety determination of the fracture mechanics evaluation calculation will therefore remain valid so long as the numbers of these events do not exceed the design basis values." In the January 13, 2006 response to RAI 4.7.2-1, NMC indicated that the pressurizer spray nozzle safe end was inspected every other refueling outage, and the pressurizer temperature element nozzles were inspected each refueling outage. NMC intends to continue the inspections at these intervals through the 60 year operating period, consistent with MRP-139, as long as this pressurizer remains in service. Supplemental Responses to NRC Questions Relating to License Renewal NRC Question Relating to FAC Management in Feedwater Ring The following question was received on February 23, 2006: "In a letter dated November 18, 2005, the applicant states that the steam generator tube integrity program is credited for managing wall thinninglflow-accelerated corrosion (FAC) of the carbon steel feedwater ring component.

The FAC is for pipe inside surface wall thinning. The staff is not aware that SG tube integrity program can manage the inside surface wall thinning due to FAC. Please provide further discussion to address this issue." The question is in regards to the response entitled "Supplement to RAI 2.3.4-1 Response Provided in NMC Letter Dated July 1, 2005, Concerning Steam Generator Feedwater Inlet Ring" provided on pages 8 and 9 of Enclosure 3 of the November 18, 2005, letter. NMC Response to NRC Question ~elat'ing to FAC Management in Feedwater Ring: As discussed in the November 18, 2005 letter, the Steam Generator Tube Integrity Program includes inspections of the J-Nozzle internals for signs of breakage or erosion in the J-Nozzle to feedwater ring weld joint. These areas are considered potentially susceptible locations that are representative of the feedwater ring in general. However, the feedwater ring is also included in the scope of the existing Palisades Flow Accelerated Corrosion Program, although specific thickness measurements for FAC have not been made. For completeness, therefore, the following changes are made to the new line item added for the feedwater ring in the November 18, 2005 letter:

I. In Table 3.1.2-4 on page 3-61, to the new line item "Feedwater Ring", a third Aging Management Program, "Flow Accelerated Corrosion" is hereby added. The associated NUREG 1801 Volume 2, Table 1, and Notes entries are "IV.DI .3-a", "3.1.1-21

", and "A, 126", respectively.

2. On page 3-63, the new plant-specific note 126 is revised to read as follows, "The Flow Accelerated Corrosion Program is credited for managing wall thinninglflow accelerated corrosion. The Steam Generator Tube Integrity Program and the Water Chemistry Program are credited for other loss of material mechanisms."

Enclosure 2 Supplemental Responses to NRC Questions Relating to License Renewal NRC Question Relating to Underclad Cracking The following question was received on March 6, 2006: In LRA Section 3.1.2.2.5, the applicant addressed growth of intergranular separations (underclad cracks) by stating that neutron fluence at the end of the extended operation has been determined to be 6 orders of magnitude less than 1 .OE19 n/cm**2. SRP-LR Section 3.1.2.2.5 states that growth of intergranular separations (underclad cracks) is a TLAA to be evaluated for all the SA 508 CI. 2 forgings where the cladding was deposited with a high heat input welding process. The staff does not agree that the magnitude of neutron fluence has anything to do with the growth of intergranular separations.

Please provide further discussion to address this issue.

NMC Response to NRC Question Relating to Underclad Cracking The full Palisades discussion that was provided in LRA section 3.1.2.2.5 is as follows: "The Palisades reactor vessel items fabricated from SA-508 Class 2 material include the primary nozzles, reactor vessel flange, and the closure head flange. NUREG-1 801 identifies this aging effect as applicable to reactor vessel items fabricated from SA-508, Class 2 materials exposed to a neutron fluence

> 1 .OE17 n/cm2. The fluence at the end of the period of extended operation at the bottom of the nozzle to shell welds (highest fluence received by an SA-508 Class 2 Palisades item) has been determined to be 6 orders of magnitude less than 1 .OE19 n/cm2, approximately 1 .OE13 n/cm2. In addition, controls on the cladding chemical composition and processes during fabrication of the Palisades reactor vessel reduced the potential for cracking of the vessel cladding. There have been no cases of underclad cracking in any clad Combustion Engineering reactor vessel subcomponents. Therefore, this aging effect does not require management for the period of extended operation for Palisades." The magnitude of the neutron fluence was included to conform with NUREG I801 (rev 0) line item IV.A2.5-b that defines "Chemically treated borated water up to 340C (644F)" and "neutron fluence greater than 10E17 nlcm-sq" as the applicable environments for the "crack growth/cyclic loading" aging effectlmechanism resulting in intergranular separation (underclad cracks).

NMC agrees that neutron fluence should not influence the crack growth/cyclic loading aging effectlmechanism. It is noted that GALL revision 1 line item IV.A2-22 (linked to IV.A2.5-b) now only includes "Reactor Coolant" as the applicable environment.

NMC's basis for concluding that underclad cracking is not a TLAA applicable to Palisades did not depend on the statement about fluence.

Supplemental Responses to NRC Questions Relating to License Renewal In a subsequent conversation, the NRC indicated a need for more detail about the balance of the LRA discussion relating to controls in Combustion Engineering's clad fabrication processes, and the lack of operating experience relating to this phenomenon in Combustion Engineering vessels.

To assist the staff with the review of this issue, NMC provides the following commitment:

NMC will submit for NRC review either a technical discussion that provides a more detailed basis for concluding that underclad cracking is not a TLAA at Palisades, or a description to be incorporated into LRA Section 4 and Appendix A which describes underclad cracking as a TLAA and identifies the appropriate disposition under 10 CFR 54.21 (c)(I). This information will be submitted by September 30, 2006.