ML052290273
| ML052290273 | |
| Person / Time | |
|---|---|
| Site: | Palisades  |
| Issue date: | 08/12/2005 |
| From: | Harden P Nuclear Management Co |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| Download: ML052290273 (12) | |
Text
NMC Committed to Nuclear Excelen Palisades Nuclear Plant Operated by Nuclear Management Company, LLC August 12, 2005 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 Response to NRC Requests for Additional Information Dated July 12, 2005 Relating to License Renewal for the Palisades Nuclear Plant In a letter dated July 12, 2005, the Nuclear Regulatory Commission (NRC) transmitted Requests for Additional Information (RAls) regarding the License Renewal Application for the Palisades Nuclear Plant. This letter responds to those requests. provides the text of, and the NMC response to, each NRC request.
Please contact Mr. Darrel Turner, License Renewal Project Manager, at 269-764-2412, or Mr. Robert Vincent, License Renewal Licensing Lead, at 269-764-2559, if you require additional information.
Summary of Commitments This letter contains no new commitments or changes to existing commitments.
I declare under penalty of perjury that the foregoing is true and correct. Executed on August
, 2005.
Paul A. Harden Site Vice President, Palisades Nuclear Plant
/\\ le Nuclear Management Company, LLC 27780 Blue Star Memorial Highway
- Covert, Michigan 49043-9530 Telephone: 269.764.2000
Enclosure (1) cc Administrator, Region III, 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 Additional Information Dated July 12, 2005 (9 pages)
NMC Responses to NRC Requests for Additional Information dated July 12, 2005 RAI B.2.1.3-1(b)
The LRA AMR Tables and AMP B.2.1.3 or AMP B.2.1.5 do not identify if any bolting is exposed to soil. The applicant is requested to identify if any bolting is used in buried applications and to clarify if the Bolting Integrity Program or the Buried Services Corrosion Monitoring Program manage such bolting.
NMC Response to NRC RAI B.2.1.3-1(b)
The Fire Protection System contains bolting that is both buried in soil and submerged in raw water. These are identified in LRA Table 3.3.2-7 as Fasteners. This table credits the Bolting Integrity Program for managing loss of preload, and the Fire Protection Program for managing loss of material. No other buried bolting has been identified in the portions of other systems that are in scope of license renewal.
1 NMC Responses to NRC Requests for Additional Information dated July 12, 2005 RAI B.2.1.3-1( c)
LRA Section B2.1.3 references EPRI NP-5769 which identifies that loss of preload is caused by a number of factors including stress relaxation (both at room temperature and elevated temperature), thermal cycling (particularly for gaskets), creep and flow of gasket material during initial compression, vibration and shock, and elastic interactions between separately-tightened bolts. Notes 206, 324 and 406 in LRA AMR Tables state that loss of preload is included here in response to recent NRC RAls on non-primary system, high temperature bolting that may experience loss of preload. Considering EPRI NP-5769, loss of preload may occur at room temperature, the applicant is requested to define high temperature and clarify if loss of preload is managed for all closure bolting within scope of license renewal.
NMC Response to NRC RAI B.2.1.3-1( c)
Loss of preload is managed for all closure bolting within the scope of license renewal for the Palisades plant regardless of temperature. As stated in LRA Section B2.1.3 on page B-27, the Bolting Integrity Program covers all bolting within the scope of license renewal, including safety related bolting, bolting for NSSS component supports, bolting for other pressure retaining components, and structural bolting. NMC has not limited the management of loss of preload by the Bolting Integrity Program to only high temperature applications.
2 NMC Responses to NRC Requests for Additional Information dated July 12, 2005 RAI B.2.1.3-1(d)
The applicant is requested to clarify if there are any in-scope, high strength (actual yield strength > 150 ksi) structural bolting or fasteners used for Palisades NSSS component supports or other non-class 1 applications.
NMC Response to NRC RAI B.2.1.3-1(d)
Review of structural and component support bolting drawings and specifications has identified A490 bolting as the only bolting type in structural applications at Palisades with the potential for actual yield strength to exceed 1 50ksi. Certified Material Test Report (CMTR) documentation is not readily available to validate actual yield strength values.
Therefore, Palisades is conservatively treating all A490 bolting as high strength bolting with yield strength potentially > 150ksi.
3 NMC Responses to NRC Requests for Additional Information dated July 12, 2005 RAI B.2.1.3-2 (a)
LRA Section B.2.1.3, preventive actions, states that the use of lubricants generally meet the recommendations of EPRI NP-5769 and NUREG-1339 and under enhancements the applicant plans a revision to the procedures that implement the credited programs, including use of lubricants and sealants to bring the Bolting Integrity Program into conformance with the NUREG-1801 program description. With regards to the use of lubricants, the use of the term "generally meet" is not clear. The applicant is requested to clarify if any exceptions to the NUREG-1801 program and its bases are necessary for the use of lubricants.
NMC Response to NRC RAI B.2.1.3-2 (a)
The Palisades Bolting Integrity Program takes no exceptions to NUREG 1801,Section XI.M18. No exceptions are taken for use of lubricants.
The term 'generally meet' should not have been used in the program description. NMC has committed (Commitment #10 in the NMC letter transmitting the Application for Renewed Operating License dated March 22, 2005) to enhance the Bolting Integrity Program to incorporate the recommendations of EPRI NP-5769 and NUREG-1339. As discussed in LRA Section B1I.1, the programs are described as they will exist after identified enhancements are incorporated. Since the Bolting Integrity Program will contain the recommendations of EPRI NP-5769 and NUREG-1339 prior to the period of extended operation, the word 'generally' is hereby deleted from the description.
4 NMC Responses to NRC Requests for Additional Information dated July 12, 2005 RAI B.2.1.3-3(a)
NUREG-1801 AMP XI.M18, element 4, recommends inspection techniques such as removing the bolt, proof test by tension or torquing, by situ ultrasonic tests or hammer tests. The applicant credits both visual and volumetric inspections of bolting. It is not clear how crack initiation due to cyclic loading or SCC is detected by visual inspection where the thread surface is not readily visible. Where visual inspection is applied, the applicant is requested to clarify how crack initiation due to cyclic loading or SCC is detected for applications where the thread surface is not readily visible. If leakage detection is the only method applied, the applicant should so clarify. In addition, if removal of the bolting and inspection during maintenance or augmented inspection is credited, the applicant should so clarify.
NMC Response to NRC RAI B.2.1.3-3(a)
NUREG-1 801, AMP XI.M1 8, element 4, states: "Structural bolting both inside and outside containment is inspected by visual inspection. Degradation of this bolting may be detected and measured either by removing the bolt, proof test by tension or torquing, by in situ ultrasonic tests, or hammer test. If this bolting is found corroded, a closer inspection is performed to assess extent of corrosion."
Management of Palisades' structural bolting is consistent with this discussion. The Palisades Bolting Integrity Program Basis Document states that structural bolting and fasteners, both inside and outside containment, are inspected by visual examination in accordance with the Structural Monitoring Program. The Structural Monitoring Program facilitates visual inspection of structural bolting. If visual degradation is observed requiring further evaluation, degradation (e.g. crack initiation due to cyclic loading or SCC) may be identified and measured by removing the bolting, proof test by tension or torquing, by in situ ultrasonic tests, or hammer tests.
Structural bolting is typically not subject to significant cyclic loading or thermal stress, so cracking due to fatigue is not an applicable aging effect. For stress corrosion cracking to occur, three conditions must exist: high stress, a corrosive environment, and susceptible material. The corrosive environment is initially precluded through use of proper lubricants and proper bolt installation practices. Visual inspection for degradation will identify the potential for SCC by detecting evidence of corrosion or a corrosive environment. If the potential for cracking is found, the extent of any degradation may be identified and measured by removing the bolting for further inspection, proof testing by tension or torquing, in situ ultrasonic testing, or hammer testing.
For inspection of pressure-retaining bolting, the Palisades Bolting Integrity Program credits the inspection requirements of ASME Section Xl for Class 1,2, and 3 pressure retaining components. For bolting in non-ASME classed pressure retaining components, Palisades applies visual inspection methodology similar to the VT-2 methodology used for ASME Section Xl Class 3 pressure retaining components. See the response to RAI B2.1.20-2(e) in NMC letter dated July 25, 2005 for additional information.
5 NMC Responses to NRC Requests for Additional Information dated July 12, 2005 RAI B.2.1.3-3(b)
LRA Section B2.1.3 identifies the ASME Section Xl Inservice Inspection Program for managing non-class 1 safety related pressure retaining and support bolting. The LRA B2.1.2 Inservice Inspection Program references the requirements of 10 CFR 50.55a for the Section XI edition. GALL Xl.M3 recommends visual, surface and volumetric examinations in accordance with IWA-2000 of the 1995 edition through the 1996 addenda of ASME Section Xl. The applicant is requested to clarify if detection of aging effects in bolting using the ASME Section XI edition identified in 10 CFR 50.55(a) is consistent with or conservative compared to the 1995 edition through the 1996 addenda identified in NUREG-1801 Xl.M3. If the new code edition is less restrictive, the applicant is requested to submit an evaluation to the NRC for review to demonstrate that aging effects are being adequately managed.
NMC Response to NRC RAI B.2.1.3-3(b)
For clarification, the Palisades Reactor Head Closure Studs (NUREG 1801 Section Xl.M3 program) are age managed under the ASME Section Xl IWB, IWC, IWD, IWF Aging Management Program (AMP) (LRA Section B.2.1.2). All other bolting that is age managed under license renewal falls under the Bolting Integrity Program (LRA Section B2.1.3), which implements the requirements of NUREG 1801 (GALL XI,M18 Bolting Integrity). However, the Bolting Integrity Program also credits the ASME section Xl IWB, IWC, IWD, IWF Aging Management Program (LRA Section B.2.1.2) for the inspection of ASME Class 1, 2, and 3 bolting.
NMC has discussed with the NRC staff various options for defining an appropriate code edition and addenda for the ASME Section Xi IWB, IWC, IWD, and IWF Aging Management Program, and decoupling the AMP from the current ASME Section XI Inservice Inspection Program under 10 CFR 50.55a. In the nearfuture, following NRC publication of NUREG 1801, Revision 1, NMC plans to submit a revised description of the ASME Section XI IWB, IWC, IWD, and IWF Aging Management Program that defines a new basis code and addenda. This revised AMP description will also impact all the other Palisades AMPs that credit this program. It is anticipated that the revised program description will credit the 2001 edition through 2003 addenda. Since this edition and addenda are expected to be endorsed by NUREG 1801, Revision 1, no additional justification of the code edition and addenda should be required.
Therefore, the future submittal of the revised program description will constitute the specific response to this question.
6 NMC Responses to NRC Requests for Additional Information dated July 12, 2005 RAI B.2.1.3-3( c)
Under "Detection of Aging Effects" item of Section B2.1.3, Bolting Integrity Program, it is indicated that structural bolting and fasteners both inside and outside containment are inspected by visual examination in accordance with the Structural Monitoring Program.
The applicant is requested to clarify how the visual examination of structural bolting and fasteners is implemented pursuant to the Palisades' Structural Monitoring Program, including a list of plant specific programs or procedures that will be used to timely dispose the identified bolting or fastener degradation events.
NMC Response to NRC RAI B.2.1.3-3( c)
Palisades' existing Structural Monitoring Program procedure includes guidance for inspection of structural bolted connections. The procedure identifies common deficiencies in bolted connections including loose or missing fasteners, insufficient coverage of slotted holes with plate washers, insufficient contact between connected parts, etc. It also provides guidance on evaluation and disposition of inspection results.
Identified deficiencies are directed to be corrected in a timely manner commensurate with their safety significance, their complexity, and other regulatory requirements. Use of the corrective action process and work request/work order process is specified to evaluate the operability of the affected SSC, the immediacy of the need for repair or replacement and ensure the appropriate level of cause determination and corrective action is completed for the identified deficiency.
Personnel performing formal structural inspections are required to have the following qualifications as a minimum: be appropriately degreed engineers from an accredited college or university; be knowledgeable in the design, evaluation and performance of nuclear structures; and have five years minimum experience in structural engineering for nuclear structures. This level of qualification eliminates any delay in providing inspection results to qualified engineering personnel for evaluation and disposition.
7 NMC Responses to NRC Requests for Additional Information dated July 12, 2005 RAI B.2.1.3-4 (a)
NUREG-1 801 AMP XI.M18 element 6 (Acceptance Criteria) recommends that immediate repairs be done for major leaks that may cause corrosion or contamination.
LRA AMP B2.1.3 states that the Palisades Bolting Integrity Program makes no distinction regarding "immediate" repairs, but instead relies upon the plant inservice inspection program and corrective action process to evaluate, prioritize and schedule repairs. The operating experience section of AMP B2.1.3 states that the Bolting Integrity program has been effective in identifying bolting degradation in a timely manner, thus ensuring that age related degradation of bolting will be effectively managed throughout the license renewal period. The applicant identifies six instances where the ISI program has been instrumental in discovering bolting degradation. The applicant concludes that reviews of internal and external assessments of the program have been reviewed and the reports demonstrate that the program has effectively identified and dispositioned issues that could have led to degraded conditions. The applicant is requested to specifically address if these reports represent objective evidence to demonstrate that the Action Request Process and Corrective Action Process have been effective in initiating timely repairs for bolting, including structural bolting and fasteners. The applicant is also requested to explain plant specific operating experience regarding aging management of any non-class 1 high strength bolting, including structural bolting.
NMC Response to NRC RAI B.2.1.3-4 (a)
The plant specific operating experience for the bolting integrity program was discussed in NMC's response to RAI B2.1.3-10 in a letter dated July 28, 2005. This response discussed how the bolting degradation was detected, how the degradation was dispositioned, and the degradation mechanism for each. Each of these situations serves as an example of how the corrective action system has been timely and effective in addressing degraded plant equipment, including bolting.
A review of Palisades' operating experience identified no examples of failure of high strength bolting.
As discussed in NMC's response to RAI B2.1.3-9 in the letter dated July 28, 2005, "...
degraded conditions would be entered promptly into the plant Corrective Action Program. The program, in turn, would require a prompt assessment of the effect of the condition on plant safety and equipment operability. Corrective actions would be assigned and completed commensurate with the safety and operational significance of the condition. The corrective action for a degraded bolt would likely include eventual replacement of that bolt, but the timing of the replacement would have to consider the safety-significance of the condition, the plant conditions needed to safely complete the work, the status of other plant equipment, the extent and complexity of repair, radiological conditions, availability of replacement parts, etc."
8 NMC Responses to NRC Requests for Additional Information dated July 12, 2005 RAI B.2.1.3-5 (a)
Section A2.3 of the LRA states that the program considers the guidelines delineated in NUREG-1339 for a Bolting Integrity Program, EPRI NP-5769 (with the exceptions noted in NUREG-1 339) for safety related bolting, and EPRI TR-1 04213 for non-safety related bolting. The use of the term "considers" is not definitive. The applicant is requested to clarify if the program "relies on" or is consistent with these documents.
NMC Response to NRC RAI B.2.1.3-5 (a)
The first sentence of Section A2.3 should read, "Palisades Bolting Integrity Program relies on the guidelines delineated in NUREG-1339, EPRI NP-5769 (with the exceptions noted in NUREG-1339) for safety-related bolting, and EPRI TR-104213 for non-safety related bolting." These documents were used as source documents for developing the Palisades Bolting Integrity Program.
9