SER Accepting Licensee Commitment to Implement GIP-2, Including Clarifications,Interpretations & Exceptions Identified in Sser 2 as Method for Resolving USI A-46 at PlantML20127P111 |
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Site: |
Millstone ![Dominion icon.png](/w/images/b/b0/Dominion_icon.png) |
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Issue date: |
11/20/1992 |
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From: |
Office of Nuclear Reactor Regulation |
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To: |
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Shared Package |
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ML20127P109 |
List: |
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References |
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REF-GTECI-A-46, REF-GTECI-SC, TASK-A-46, TASK-OR GL-87-02, GL-87-2, NUDOCS 9212020070 |
Download: ML20127P111 (5) |
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Category:SAFETY EVALUATION REPORT--LICENSING & RELATED ISSUES
MONTHYEARML20211G9631999-08-30030 August 1999 SER Accepting Licensee Response to GL 96-05, Periodic Verification of Design-Basis Capability of Safety-Related Motor-Operated Valves ML20196J2191999-06-30030 June 1999 SER Concluding That Licensee USI A-46 Implementation Program,In General,Met Purpose & Intent of Criteria in GIP-2 & Staff Sser 2 for Resolution of USI A-46 ML20207G6411999-06-0303 June 1999 Safety Evaluation Supporting Amends 105,235 & 171 to Licenses DPR-21,DPR-65 & NPF-49,respectively ML20206M4631999-05-11011 May 1999 Safety Evaluation Supporting Alternative Proposed by Licensee to Perform Ultrasonic Exam on Inner Surface of Nozzle to safe-end Weld ML20206G6221999-05-0404 May 1999 SER Accepting Util Request to Apply leak-before-break Status to Pressurizer Surge Line Piping for Millstone Nuclear Power Station,Unit 2 ML20204H7131999-03-17017 March 1999 Safety Evaluation Concluding That NNECO Provided Adequate Justification for Deviations from RG 1.97,Rev 2, Recommendations,For Instrumentation Monitoring CST Level & Containment Area Radiation at Mnps Unit 2 ML20204C9441999-03-10010 March 1999 Safety Evaluation Denying Licensee Request for License Amend to Revise Frequency of Certain SRs for Electrical Power Sys ML20207L2631999-03-0505 March 1999 Safety Evaluation Supporting Amend 104 to License DPR-21 ML20207L5961999-02-22022 February 1999 Safety Evaluation Concluding That Code Requirements,Which Require 100 Percent Volumetric Exam of RPV flange-to-shell, Impractical to Perform to Extent Required & That Alternative Provide Reasonable Assurance of Structural Integrity ML20203D7601999-02-11011 February 1999 Safety Evaluation Supporting Millstone 1 Certified Fuel Handler Training & Retraining Program ML20196B0501998-11-24024 November 1998 Safety Evaluation Re Licensee 960213 Submittal of 180-day Response to GL 95-07, Pressure Locking & Thermal Binding of Safety-Related Power-Operated Gate Valves, for Plant,Unit 2 ML20155K1981998-11-0909 November 1998 Safety Evaluation Re Application of leak-before-break Status to Portions of Safety Injection & Shutdown Cooling Sys ML20195B8711998-11-0909 November 1998 Safety Evaluation Approving Revised Evaluation of Primary Cold Leg Piping leak-before-break Analysis for Plant ML20155C3781998-10-30030 October 1998 SER Denying Amend to Allow Changes to Fsar.Nrc Found That NNECO Had Not Considered Diversity Provided by Switch in Control Room That Removes Power to 1 of 2 MOV in SDC Sys Flow Path in Evaluation of High Low Pressure Design ML20155C8441998-10-29029 October 1998 Safety Evaluation Accepting Licensee Proposal to Withdraw ATWS Test Commitment ML20238F2781998-08-27027 August 1998 SER Related to Proposed Rev 20 to Northeast Utilities Quality Assurance Program Topical Rept for Millstone Nuclear Power Station,Units 1,2 & 3 ML20237D5001998-08-20020 August 1998 SER Approving Code Case N-389-1, Alternative Rules for Repairs,Replacements,Or Mods,Section Xi,Div 1 ML20236U7051998-07-22022 July 1998 Safety Evaluation Granting All Requests for Relief W/Exception of Requests RR-89-17 (Authorized for Class 1 Sys Only) & RR-89-21.Requests RR-13 & RR-14 Will Be Addressed in Separate Evaluation ML20236K6971998-07-0101 July 1998 SER Accepting Third 10-year Interval Inservice Insp Program Plan,Rev 2 & Associated Request for Relief & Proposed Alternatives for Plant,Unit 2 ML20236K3531998-07-0101 July 1998 Safety Evaluation Supporting Amend 218 to License DPR-65 ML20249C2541998-06-24024 June 1998 Safety Evaluation Accepting Proposed Rev 19 to NNECO QAP Topical Rept & Amended Through 980609.Informs That NNECO Exception to Provisions in Paragraph 10.3.5 of Constitutes Temporary & Acceptable Alternative ML20248J0031998-06-0404 June 1998 Safety Evaluation Accepting Millstone Nuclear Power Station Emergency Plan ML20248M2991998-06-0202 June 1998 Safety Evaluation Approving Application Re Restructuring of Central Maine Power Co by Establishment of Holding Company ML20248C4131998-05-26026 May 1998 SER of Individual Plant Exam of External Events Submittal on Millstone Nuclear Power Station,Unit 3 ML20217M4181998-04-30030 April 1998 Suppl Safety Evaluation Accepting Licensee RCS Pressure & Heat Removal by Containment Heat Removal Sys post-accident Monitoring Instrumentation ML20216G7921998-03-13013 March 1998 Safety Evaluation Authorizing Proposed Alternative to Check Valve Obturator Movement Requirements of OM-10 for SIL Accumulator Outlet for Listed Check Valves ML20203E8521998-02-17017 February 1998 SER Accepting Request for Relief from Requirements of 10CFR50.55a(f) for Performing Required Inservice Testing of Certain Class 2 Components IAW ASME Boiler & Pressure Vessel Code Section XI for Plant,Unit 3 ML20203E9341998-02-17017 February 1998 SER Accepting Request for Relief from Requirements of 10CFR50.55a(g) for Performing Required Exams for Certain Class 1 Components IAW ASME Boiler & Pressure Vessel Code Section XI for Plant,Unit 3 ML20203E2441998-02-0909 February 1998 Safety Evaluation Accepting Re Approval of Realistic,Median Centered Spectra Generated for Resolution of USI-A-46 ML20198R9941998-01-13013 January 1998 SER Accepting Licensee Response to GL 95-07, Pressure Locking & Thermal Binding of Safety-Related Power-Operated Gate Valves, for Millstone Nuclear Power Station,Unit 3 ML20202H7461997-12-10010 December 1997 Safety Evaluation Accepting Licensee Position That Correction of AC-11 Single Failure Vulnerability Unncessary ML20202J0911997-12-0202 December 1997 Safety Evaluation Accepting Proposed Exemption,Which Meets Special Circumstance Given in 10CFR50.12(a)(2)(ii) ML20198S2411997-10-31031 October 1997 SE Accepting Licensee Request for Deviations from Recommendations in Reg Guide 1.97,Rev 2 for Temp & Flow Monitoring Instrumentation for Cooling Water to ESF Sys Components & Containment Isolation Valve Position ML20212G5991997-10-27027 October 1997 Safety Evaluation Supporting Amend 103 to License DPR-21 ML20217K8801997-10-27027 October 1997 Correction to Safety Evaluation Supporting Amend 103 to License DPR-21.Phrase or Rod Block Protection Has Been Deleted from Listed Sentence in Staff Associated SE ML20212F1381997-10-22022 October 1997 Safety Evaluation Supporting Amend 102 to License DPR-21 ML20217M9301997-08-19019 August 1997 Safety Evaluation Accepting Continued Operation W/O High Startup Rate Trip by Nene for Millstone,Unit 2 ML20149J2661997-07-23023 July 1997 Safety Evaluation Accepting Changes & Reanalyses in ECCS Evaluation Models & Application of Models for Plant,Unit 2 ML20141L8821997-05-28028 May 1997 Safety Evaluation Supporting Amend 101 to License DPR-21 ML20138A0111997-04-23023 April 1997 Safety Evaluation Accepting Licensee Proposal,Not to Perform Type C Leakage Rate Testing on 14 Subject CIVs ML20137V5931997-04-15015 April 1997 Safety Evaluation Supporting Amend 100 to License DPR-21 ML20137U3121997-04-10010 April 1997 Safety Evaluation Supporting Amends 99,206 & 135 to Licenses DPR-21,DPR-65 & NPF-49,respectively ML20134A0331997-01-23023 January 1997 Safety Evaluation Accepting Util Proposed Alternatives to ASME Code Requirements ML20133N3401997-01-14014 January 1997 Safety Evaluation Supporting Amend 98 to License DPR-21 ML20135C4221996-12-0202 December 1996 Safety Evaluation Accepting Proposed Alternative Described in Relief Request R-1 Re Valve Inservice Testing Program at Facility ML20128P4381996-10-0909 October 1996 Safety Evaluation Accepting Review of Cracked Weld Operability Calculations & Staff Response to NRC Task Interference Agreement ML20128L7541996-10-0404 October 1996 Safety Evaluation Supporting Amend 97 to License DPR-21 ML20248C5451995-05-0202 May 1995 SER on Millstone Unit 3 Individual Plant Exam of External Events to Identify plant-specific Vulnerabilities,If Any,To Severe Accidents & Rept Results Together W/Any licensee-determined Improvements & C/A to Commission ML20248C5731994-07-19019 July 1994 SER Step 1 Review of Individual Plant Exam of External Fire Events for Millstone Unit 3 ML20059H4991994-01-24024 January 1994 Safety Evaluation Accepting Revised Responses to IEB-80-04 Re MSLB Reanalysis 1999-08-30
[Table view] Category:TEXT-SAFETY REPORT
MONTHYEARML20217P5391999-10-25025 October 1999 Rev 0,Change 1 to Millstone Unit 1 Northeast Utils QA Program ML20217C8721999-10-0606 October 1999 Rev 21,change 3 to MP-02-OST-BAP01, Nuqap Topical Rept, App F & G Only B17896, Monthly Operating Rept for Sept 1999 for Millstone Nuclear Power Station,Unit 1.With1999-09-30030 September 1999 Monthly Operating Rept for Sept 1999 for Millstone Nuclear Power Station,Unit 1.With B17894, Monthly Operating Rept for Sept 1999 for Millstone Nuclear Power Station,Unit 2.With1999-09-30030 September 1999 Monthly Operating Rept for Sept 1999 for Millstone Nuclear Power Station,Unit 2.With B17898, Monthly Operating Rept for Sept 1999 for Millstone Nuclear Power Station,Unit 3.With1999-09-30030 September 1999 Monthly Operating Rept for Sept 1999 for Millstone Nuclear Power Station,Unit 3.With ML20216J4341999-09-24024 September 1999 Mnps Unit 3 ISI Summary Rept,Cycle 6 ML20211N8401999-09-0202 September 1999 Rev 21,change 1 to Northeast Utils QA TR, Including Changes Incorporated Into Rev 20,changes 9 & 10 B17878, Monthly Operating Rept for Aug 1999 for Mnps,Unit 1.With1999-08-31031 August 1999 Monthly Operating Rept for Aug 1999 for Mnps,Unit 1.With B17874, Monthly Operating Rept for Aug 1999 for Millstone Nuclear Power Station,Unit 3.With1999-08-31031 August 1999 Monthly Operating Rept for Aug 1999 for Millstone Nuclear Power Station,Unit 3.With ML20216F5141999-08-31031 August 1999 Rept on Status of Public Petitions Under 10CFR2.206 B17879, Monthly Operating Rept for Aug 1999 for Millstone Nuclear Power Station,Unit 2.With1999-08-31031 August 1999 Monthly Operating Rept for Aug 1999 for Millstone Nuclear Power Station,Unit 2.With ML20211G9631999-08-30030 August 1999 SER Accepting Licensee Response to GL 96-05, Periodic Verification of Design-Basis Capability of Safety-Related Motor-Operated Valves ML20211A6561999-07-31031 July 1999 Monthly Operating Rept for July 1999 for Millstone Nuclear Power Station,Unit 2 B17858, Monthly Operating Rept for July 1999 for Millstone Nuclear Power Station,Unit 3.With1999-07-31031 July 1999 Monthly Operating Rept for July 1999 for Millstone Nuclear Power Station,Unit 3.With B17856, Monthly Operating Rept for July 1999 for Millstone Nuclear Power Station,Unit 1.With1999-07-31031 July 1999 Monthly Operating Rept for July 1999 for Millstone Nuclear Power Station,Unit 1.With ML20210J0311999-07-21021 July 1999 Rev 20,Change 10 to QAP 1.0, Organization ML20210E5931999-07-19019 July 1999 Revised Page 16 of 21,to App F of Northeast Util QA Program Plan ML20210C5911999-07-15015 July 1999 Revised Rev 20,change 10 to Northeast Util QA Program TR, Replacing Summary of Changes ML20210A0411999-07-15015 July 1999 Rev 20,change 10 to Northeast Util QA Program Tr B17814, Special Rept:On 990612 B Train EDG Failed to Restart within 5 Minutes Following Completion of 18 Month 24 H Endurance Run Required by TS 4.8.1.1.2.g.7.Caused by Procedural inadequacy.Re-performed Hot Restart Via Manual Start1999-07-12012 July 1999 Special Rept:On 990612 B Train EDG Failed to Restart within 5 Minutes Following Completion of 18 Month 24 H Endurance Run Required by TS 4.8.1.1.2.g.7.Caused by Procedural inadequacy.Re-performed Hot Restart Via Manual Start ML20209D1881999-07-0101 July 1999 Rev 20,change 9 to Northeast Util QA Program Tr ML20196J2191999-06-30030 June 1999 SER Concluding That Licensee USI A-46 Implementation Program,In General,Met Purpose & Intent of Criteria in GIP-2 & Staff Sser 2 for Resolution of USI A-46 ML20211A6751999-06-30030 June 1999 Revised Monthly Operating Rept for June 1999 for Millstone Nuclear Power Station,Unit 2,providing Revised Average Daily Unit Power Level & Operating Data Rept ML20196A8451999-06-30030 June 1999 Post Shutdown Decommissioning Activities Rept ML20209J0541999-06-30030 June 1999 Monthly Operating Rept for June 1999 for Millstone Unit 2 B17830, Monthly Operating Rept for June 1999 for Millstone Nuclear Power Station,Unit 3.With1999-06-30030 June 1999 Monthly Operating Rept for June 1999 for Millstone Nuclear Power Station,Unit 3.With ML20196K1791999-06-30030 June 1999 Addendum 6 to Millstone Unit 2 Annual Rept, ML20196J1821999-06-30030 June 1999 Rev 21,Change 0 to Northeast Utilities QAP (Nuqap) Tr B17833, Monthly Operating Rept for June 1999 for Millstone Power Station,Unit 1.With1999-06-30030 June 1999 Monthly Operating Rept for June 1999 for Millstone Power Station,Unit 1.With ML20195H1011999-06-11011 June 1999 Rev 20,change 8 to Northeast Utilities QAP (Nuqap) TR ML20207G6411999-06-0303 June 1999 Safety Evaluation Supporting Amends 105,235 & 171 to Licenses DPR-21,DPR-65 & NPF-49,respectively ML20211A6631999-05-31031 May 1999 Revised Monthly Operating Rept for May 1999 for Millstone Nuclear Power Station,Unit 2,providing Revised Average Daily Unit Power Level,Operating Data Rept & Unit Shutdowns & Power Reductions B17808, Monthly Operating Rept for May 1999 for Millstone Nuclear Power Station,Unit 3.With1999-05-31031 May 1999 Monthly Operating Rept for May 1999 for Millstone Nuclear Power Station,Unit 3.With ML20211B7351999-05-31031 May 1999 Cycle 7 Colr B17804, Monthly Operating Rept for May 1999 for Mnps,Unit 2.With1999-05-31031 May 1999 Monthly Operating Rept for May 1999 for Mnps,Unit 2.With B17807, Monthly Operating Rept for May 1999 for Mnps,Unit 1.With1999-05-31031 May 1999 Monthly Operating Rept for May 1999 for Mnps,Unit 1.With ML20209J0661999-05-31031 May 1999 Revised Monthly Operating Rept for May 1999 for Millstone Unit 2 ML20206M4631999-05-11011 May 1999 Safety Evaluation Supporting Alternative Proposed by Licensee to Perform Ultrasonic Exam on Inner Surface of Nozzle to safe-end Weld ML20206J8351999-05-0707 May 1999 Rev 20,Change 7 to QAP-1.0, Northeast Utls QA Program (Nuqap) Tr ML20206G6221999-05-0404 May 1999 SER Accepting Util Request to Apply leak-before-break Status to Pressurizer Surge Line Piping for Millstone Nuclear Power Station,Unit 2 B17782, Monthly Operating Rept for Apr 1999 for Millstone Nuclear Power Station,Unit 1.With1999-04-30030 April 1999 Monthly Operating Rept for Apr 1999 for Millstone Nuclear Power Station,Unit 1.With ML20205R3531999-04-30030 April 1999 Addendum 4 to Annual Rept, B17775, Monthly Operating Rept for Apr 1999 for Millstone Nuclear Power Station Unit 3.With1999-04-30030 April 1999 Monthly Operating Rept for Apr 1999 for Millstone Nuclear Power Station Unit 3.With ML20205K6141999-04-30030 April 1999 Non-proprietary Version of Rev 2 to Holtec Rept HI-971843, Licensing Rept for Reclassification of Discharge in Millstone Unit 3 Spent Fuel Pool ML20206E2971999-04-30030 April 1999 Rev 1 to Millstone Nuclear Power Station,Unit 2 COLR - Cycle 13 B17777, Monthly Operating Rept for Apr 1999 for Millstone Unit 2. with1999-04-30030 April 1999 Monthly Operating Rept for Apr 1999 for Millstone Unit 2. with ML20205Q5891999-04-0909 April 1999 Rev 20,change 6 to QAP-1.0,Northeast Utils QA Program TR ML20205R8751999-04-0909 April 1999 Provides Commission with Staff Assessment of Issues Related to Restart of Millstone Unit 2 & Staff Recommendations Re Restart Authorization for Millstone Unit 2 ML20206T3991999-03-31031 March 1999 First Quarter 1999 Performance Rept, Dtd May 1999 B17747, Monthly Operating Rept for Mar 1999 for Millstone Nuclear Power Station,Unit 1.With1999-03-31031 March 1999 Monthly Operating Rept for Mar 1999 for Millstone Nuclear Power Station,Unit 1.With 1999-09-30
[Table view] |
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ENCLOSURE SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION RELATED TO 120-DAY RESPONSE TO SUPPLEMENT NO. 1 TO GENERIC LETTER 87-02 NORTHEAST NUCLEAR ENERGY COMPANY MILLSTONE NUCLEAR POWER STATION. UNIT 2 DOCKET NO. 50-336 BACKGROUND By letter dated September 21, 1992, the Northeast Nuclear Energy Company, the licensee, submitted the response to Supplement No. I to Generic Letter 87-02 (GL FG -J2), " Verification of Seismic Adequacy of Mechanical and Electrical Equipment in Operating Reactors, Unresolved Safety Issue (USI) A-46," dated May 22, 1992, for the Millstone Nuclear Power Station, Unit 2. In Supplement No. I to GL 87-02, the staff requested that affected licensees submit the following information within 120 days of the issue date of the supplement:
- 1. A statement whether you commit to use botn the Seismic Qualification Utility Group (SQUG) commitments and the implementation guidance provided in the Generic Implementation Procedure, Revision 2 (CIP-2) as supple 0ented by the staff's Supplemental Safety Evaluation Report No. 2 gSSER-2) for the resolution of USI A-46. In this case, any deviation from GlP-2, as supplemented by the SSER No. 2, must be identified, justified, and documented. If you do not make such a commitment, you must provide your alternative for responding to GL 87-02,
- 2. A plant-specific sc dule for the implementation of the GIP and submission of a regrt to the staff that summarizes the results of the USI A-46 review, if you are committing to implement GIP-2. This schedule shall be such that each affected plant will complete its implementation and submit the summary report within 3 years after the issuance of the SSER No. 2, unless otherwise justified.
- 3. The detailed information as to what procedures and criteria were used to generate the in-structure response spectra to be used for USI A-46 as requested in the SSER No. 2. The licensee's in-structure response spectra are considered acceptable for USI A-46 unless the staff indicates otherwise during a 60-day review period.
9212O20070 921120 PER ADOCK 05000336 P PDR
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r In addition, the stcff requested in SSER No. 2 that the licensee inform the staff in the 120-day response if it intends to change its licensing basis _to reflect a commitment to the USI A-46 (GIP-2) methodology for verifying the seismic adequacy of mechanical and electrical equipment, prior to receipt of the sta~f's plant-specific safety evaluation resolving USI A-46. This report provides the staff's evaluation of the licensee's response.
EVALVAT!0N With regard to Item I, the licensee stated that, "CYAPC0 and NGC0 intend to comply with the SQUG commitments set forth in Revision 2 of the GIP, including the clarifications, interpretations, and exceptions identified in SSER-2 in order to satisfy GL 87-02." The staff recognizes that the licensee has chosen to implement GIP-2, including both the SQUG vammitments and the implementation guidance, for responding to GL 87-02. The staff finds that this is an acceptable method to resolve USI A-46 Millstone Nuclear Powe" Station, Unit 2. .
The licensee indicated that it plans to use existing seismic qualification test reports to demonstrate seismic adequacy for any equipment on its safe shutdown equipment list (SSEL) which were previously qualified to IEEE 344-1975. The staff finds that tnis approach is acceptable for verifying equipment operability, but the licensee should also verify the seismic adequacy of the anchorage of this equipment in accordance with the criteria and procedures approved by the staff in SSER No. 2.
The licensee stated that it intends to use the Seismic Margin Methods defined in the Electric Power Research Institute's (EPRI) Report NP-6041-SL, dated August 1991, as one option for the resolution of equipment outliers. The methods defined in this report were intended to be used in conjunction with the seismic margin earthquake (SME), and not with the safe shutdown earthquake (SSE) used in USI A-46 reviews. The criteria and methods defined in the EPRI rep -t are less conservative than those defined in GIP-2. Therefcre, the methods defined in this report are, in general, not acceptable to the staff for resolving USI A-46 issues. Although the-staff acknowledges that outlier resolution is beyond the scope of GIP-2, the staff generally endorses, with the clarifications provided in SSER No. 2, the types of outlier resolution described in Section 5 of GIP-2 (_1.e., dynamic testing, engineering analysis, physical repair, and replacement). As stated in Section II.5 of SSER No. 2, "It is the responsibility of the utility to resolve outliers, using existing procedures (e.g., plant-spect:;c procedural controls and QA requirements) as it would resolve any other seismic concerns."- The staff will corsider the application of rome of the criteria provid d in EPRI Report NP-6041-SL, for the _ resolution of equipment outliers, on a case-by-case basis.
With regard 0 Item 2. the licensee stated that it will submit the Safe Shutdown Eque ant List Report, the Relay Evaluation Report, and the Seismic Evaluation Re,. ct to the NRC providino the results of the USI A-46 program at the Millstone Nuclear Power Station, Unit 2, within 180 days following the
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4 completion of Cycle #12 refueling-outage (Winter 1994). The proposed schedule for Millstone Unit 2 is within the 3-year response period requestod by the
-staff and is therefore acceptable.
With regard to Item 3, the staff has reviewed the licensee response with 'a particular objective of assessing the acceptability of the response to items 11.4.2.3 and 11.4.2.4 (as applicable) of the Supplemental Safety Evaluation No. 2 (SSEP.-2).
In compliance with the requirements of SSER-2, the licensee submitted the requested information on the subject matter. The staff has reviewed and evaluated the .nformation which can be summarized as follows:
- 1. The ground response spectra used envelopes the Housner spectra at all frequencies and the Modified Newmark spectra at frequencies higher than 7 cps. The input accelerations are: 0.099 horizontal and 0.06g vertical for OBE, and 0.179 horizontal and 0.llg vertical for SSE.
- 2. Structural damping values used are either less than or equal to those in R.G. 1.61.
- 3. The dynamic analysis codels used ere basically stick models with lumped masses.
- 4. All of the structures are supported basically on bedrock. However some of the structures are supported on shallow compacted structural backfill above the bedrock.
- 5. Fixed base assumption is used for the structures supported on bedrock, and.
soll springs and dashpots are used in the dynamic analysis for structures supported on compacted backfill.
- 6. The effects of the vertical and horizontal components of the earthquakes are assumed to occur simultaneously-and combined directly.
- 7. Analyses for vertical direction as well as for horizontal direction using the ground design spectrum curves are performed.
- 8. The in-structure response spectra are broadened in accordance with RG 1.122.
9, a) To obtain in-structure response spectra for SSE, the values developed i for-0BE are multiplied by the factor of 2 b) The time history used to generate the in-structure responses is a composite of the N69W components of the 1952 Taft earthquake and N-S components of the 1940 EL Centro earthquake.
c) The response spectrum method of analysis is used for the seismic analysis of structures.
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, it is the :taff position that if the licensee follows the criteria and procedure _as summarized above in the generation of the in-structure response i spectra, " Conservative Design" in-structure response spectra should result.
Based on our review of the licensee response and the staft positions delineated in SSER-2, we conclude that the licensee response is adequate and acceptable. This_ conclusion is based on the assumption that the statements made in the submittal 1 cluding the criteria and procedure used in the generation of the in-structure response spectra, correctly reflect what is contained in the FSAR on seismic design and bther licensing basis. The str.ff may audit the process by which the in-structure response spectra were generated.
The licensee indicated that, as part of the resolution of GL 87-02, it intends to change its licensing basis, via 10'CFR 50.59, to include the GIP methodologies as an option for demonstrating the seismic adequacy of new and replacement plant equipment. The staff recognizes that the licensee may-revise its licensing basis in-accordance with 10 CFR 50.59 to reflect the acceptability of the USI A-46 (GIP, methodviogy for verifying the seismic adequacy of electrical and mechanical equipment covered by the GIP. However, since the licensee intends to augment its licensing _ basis to include the GIP .
methodology as an option for verifying seismic adequacy, rather than revise its licensing basis such that the GIP-2 would be the sole methodology, the staff caution, that it is not acceptable to combine any part of GIP-2 with the current licensing basis methodologies such that it results in a less conservative approach than if CIP-2 cr the current licensing basis methe ciogies were applied separately.
-CONLLUSIONS The staff finds that the licenste's commitment to implement GIP-2, including the clarifications, interpretations and exceptions identif'ed in SSER No. ~2, is an acceptable method for resolving USI A 46 at the Millstone Nuclear Power Station, Unit 2.
The staff finds that it is acceptable for the licensee to use previously performed anchorage evaluations for USI A-46 provided that the evaluations meet the criteria and procedures approved in SSER No. 2 (Section 11.4.4). The i -staff also finds that it is acceptable to use existing seismic. qualification test reports to demonstrate operability for SSEL equipment which was qualified to IEEE 344-1975.
N methods defined-in EPRI Report NP-6041-SL are, in general, not acceptable t; the staff for resolving equipment outliers. However, the staff will
- consider the application of some of the criteria provided in EPRI Report NP-6041-SL, for the resolution of equipment outliers, on a case-by-case basis.
The proposed implementation schedule for Millstone Unit 2 is within the 3-year response period requested by the staff and is therefore acceptable.
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J The staff concludes that the licensee response with respect to in-structure response spectra is adequate and acceptabi'. This conclusion is based on the assumption that the statements made in the s'ibmittal, including the criteria and procedure used in the g-aneration of the in-structure response spectra, ccrrectly ret' lect what is contained in the FSoR on seismic design and other-licensing basis. The staff may audit the process by which the in-structure response spectra were generated.
The staff recognizes that the licensee may revise its licensing basis in accordance with 10 CFR 50.59 to reflect the acceptibility of the USI A-46 I, GIP) methodology for verifying the seismic adequacy of electrical and mechanical equipment covered by the GIP. However, since the licensee intends ,
to augment its licensing basis to include the GIP methodology as an option for !
verifying seismic adequacy, rather than revise its licensing basis such that the GIP-2 would be the sole methodology, the staff cautions that it is not acceptable to combine any part of GIP-2 with the current licensing basis methodologies such that it results in a less onservative approach than if GIP-2 or the current licensing basis methodoiogies were applied separately.
Principal Contributors: C. P. Tan M. McBrearty P. Chen Date: November 20, 1992 P
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