ML18066A881
| ML18066A881 | |
| Person / Time | |
|---|---|
| Site: | Palisades  |
| Issue date: | 02/14/1997 |
| From: | Bordine T CONSUMERS ENERGY CO. (FORMERLY CONSUMERS POWER CO.) |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| NUDOCS 9702240507 | |
| Download: ML18066A881 (6) | |
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consumers Power POWERl#li MIClllliAN'S l'IUllilfUS Palisades Nuclear Plant: 27780 Blue Star Memorial Highway, Covert, Ml 49043 February 14, 1997 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20555 DOCKET 50-255 - LICENSE DPR PALISADES PLANT Thomas C. Bordlne Manager, Licensing SAFETY RELATED PIPING REVERIFICATION PROGRAM - PERIODIC STATUS -
JANUARY, 1997 The Safety Related Piping Reverification Program (SRPRP) was initiated to reverify the seismic design adequacy of large bore (> 2" nominal diameter) piping systems.
The scope consists of physical walkdowns of accessible piping and pipe supports, performance of analysis for both piping and supports to current design criteria, and implementation of required modifications.
The purpose of this report is to summarize the results of the program work completed during the 1996 refueling outage and to identify future program direction.
Scope Phase I of the program consisted of reverification of 18 piping stress packages containing approximately 300 pipe supports. Phase I was completed in October of 1992. The results of this portion of the progr_am were transmitted to the NRC in a letter dated October 30, 1992.
Phases llA and 118 consisted of reverification of 13 piping stress packages containing
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results of this portion of the program were transmitted to the NRC in a letter dated September 30, 1993.
2 Phase llC of the program consisted of 21 piping stress packages containing 755 pipe supports. Walkdowns for the Phase llC effort were completed during the 1992 refueling outage in October of 1992. Analytical work and installation of required modifications were completed as plant conditions permitted. The last modifications required by Phase llC were completed during the 1995 refueling outage which ended in August, 1995.
Phase llD is the final phase of the SRPRP program consisting of 25 piping stress packages which are listed in Attachment 1. Walkdowns for all of the Phase llD piping and pipe supports have been completed. Six of the Phase llD stress packages, which included 181 pipe supports, were completed during the 1996 refueling outage which ended in December 1996. The remaining 19 stress packages will be completed by the end of the 1998 refueling outage.
Results - Phase llD Two of the six Phase llD stress packages completed in support of the 1996 refueling outage were reanalyzed and dispositioned in conjunction with major modifications to their respective systems, as follows:
SP03358 -Auxiliary Feedwater Steam Supply System
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SP07016 - Diesel Fuel Oil Transfer System (
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The reanalyses of these packages were based on SRPRP walkdown data and were performed in accordance with SRPRP criteria.
In addition to those pipe support modifications required as a result of the FC-966 changes, six additional pipe support modifications attributable to SRPRP were identified and installed in SP03358 during the 1996 refueling outage. Four modifications attributable to SRPRP were required for SP07016.
Four other SRPRP Phase llD stress package~ were completed in 1996. All modifications required to bring these packages into FSAR compliance were installed prior to the refueling outage while the plant was on line. summarizes the number of SRPRP modifications made for each of the Phase llD stress packages completed in 1996.
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3 Consistent with earlier phases of the program, none of the piping systems completed in this portion of Phase llD exceeded the Palisades interim operability criteria which were submitted to the NRC staff on November 22, 1989.
Trending At the completion of Phases I, llA/B and llC, trending studies were performed and documented. Based on root cause analyses of as-built and design discrepancies, the trending studies provided a basis for refocusing of requirements and processes for future program phases.
The results of the trending studies indicated that the majority of modifications were due to design criteria changes (i.e., response spectra peak broadening, use of RegulatorY Guide 1.60 spectra, localized effects due to integral welded attachments to pipe, relative seismic movements between buildings, etc.). As-built discrepancies by themselves typically did not lead to modifications.
Based on Phases I and llA/llB tr~nding results, a refocusing of the walkdown process was implemented for Phase llC. On the basis that as-built discrepancies did not lead to modifications, a revised walkdown process was implemented which required less rigorous inspections of selected pipe support attributes. Phase llC trending results were found to be consistent with earlier phases. On this basis, the Phase llD walkdowns were performed with the same criteria used on Phase llC.
The visual inspection criteria for piping configuration verification have remained unchanged. Likewise, requirements for pipe support inspection for missing and loose fasteners have continued as required per the Pipe Support Preventive Maintenance program.
Given the consistency in trending results regarding the significance of design criteria changes as modification root causes, piping and pipe support analysis requirements have remained virtually unchanged throughout the program.
Although no formal trending is planned for Phase llD (since it is the last phase of the program), an informal evaluation of results to date indicates consistency with earlier phases.
Future Program Direction The balance of the SRPRP program consists of the remainder of Phase llD, (i.e., 19 stress packages containing 249 supports). As discussed above, all walkdowns are
4 complete. All analyses and the implementation of required modifications will be completed by the end of the 1998 refueling outage. It is anticipated that the majority of modifications can be installed prior to the refueling outage while the plant is on line.
SUMMARY
OF COMMITMENTS This letter contains no new commitments and no revisions to existing commitments.
Thomas C. Berdine Manager, Licensing CC Administrator, Region Ill, USNRC Project Manager, NRR, USNRC NRC Resident Inspector - Palisades Attachment
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ATTACHMENT 1
. CONSUMERS POWER COMPANY PALISADES PLANT DOCKET 50-255 SAFETY RELATED PIPING REVERIFICATION PROGRAM PERIODIC STATUS -JANUARY, 1997 PHASE llD SCOPE
SUMMARY
1 Page
SAFETY RELATED PIPING REVERIFICATION PROGRAM PHASE 110 SCOPE
SUMMARY
Stress No. of No. of Package System Supports Mods.
Comments 03323 Chemical & Volume Control 82 03324 Spent Fuel Pool System 48 5
Completed in SRPRP 1996 Phase 110 Scope 03326 Safety Injection/Shutdown Cooling 16 03327 Demineralized Makeup Water 10 0
Completed in SRPRP 1996 Phase 110 Scope 03328 Demineralized Makeup Water 0
03329 Clean Radwaste System 9
03330 Clean Radwaste System 2
03331 Condensate System 2
03332 Condensate System 20 03339 Gaseous Radwaste System 5
03345 Radwaste System 8
2 Completed in SRPRP 1996 Phase 110 Scope 03347 Radwaste System 4
03351 Clean Radwaste System 7
03353 HVAC Containment Purge 4
03354 HVAC Containment Purge 1
03355 HVAC Containment Purge 2
03357 Plant Heating System 3
03358 Main Steam System 81 6
Completed in 1996 as part of FC-966 03377 Chemical & Volume Control 34 03379 Feedwater System 23 1
Completed in SRPRP 1996 Phase 110 Scope 03381 Spent Fuel Pool System 0
03390 Clean Radwaste System 19 07015 Primary Containment Venting 25 07016 Diesel Fuel Oil Supply System 11 4
Completed in 1996 as part of FC-958 07017 Condensate System 14 (25 pkgs)
TOTAL 430