ML18054B565

Provides Justification for Excluding Piping Associated W/Porv/Block Valve Mods & Plans for Walkdowns of Piping. Piping Sys or Portions of Piping Sys Covered by Phase I of safety-related Piping Reverification Program Listed

ML18054B565
Person / Time
Site:	Palisades
Issue date:	04/12/1990
From:	Smedley R CONSUMERS ENERGY CO. (FORMERLY CONSUMERS POWER CO.)
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
NUDOCS 9004250181
Download: ML18054B565 (3)

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MICHl&AN'S PRO&RESS General Offices: 1945 West Parnall Road,Jackson,'MI 49201 * (517) 788-0550 April 12, 1990 Nuclear Regulatory Commission Document Control Desk Washington, DC 20555 DOCKET 50-255 - LICENSE DPR PALISADES PLANT -

SAFETY-RELATED PIPING REVERIFICATION PROGRAM -

PORV/BLOCK*VALVE MODIFICATION AS-BUILT WALKDOWNS Consumers Power Company letter dated January 10, 1990, presented the details of our reverification program for Safety-Related Piping 2-~ inches and larger. NRC letter dated March 21, 1990 provided that the program plan and schedule presented by Consumers Power Company was acceptable with exception of our exclusion of the piping associated with the PORV/block valve modification completed at the end of 1989. The following provides our justification for excluding this piping and our plans regarding walkdowns of the subject piping.

As presented in our January 10, 1990 submittal, the Safety-Related Piping Reverification Program will involve (1) physical walkdowns, (2) piping stress analysis reconciliation and verification, and (3) pipe support calculation reconciliation and verifications. The program is divided into two phases.

Phase I represents a sample of piping selected to assure that primary coolant system (PCS) inventory is maintained, that PCS inventory can be borated to shutdown concentrations, and that redundant mechanisms exist to remove decay heat. The following piping systems or portions of piping systems are covered in Phase I:

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' -" Palisades Plant Safety-Rel Piping Reverification April 12, 1990 Piping Number of Containment System Linear Feet Hangers/Supports Inside (I)/Outside(O)

ESS 947 1 61 I AFW 309' 24 I AFW 737' 72 0 HPSI 206' 19 I HPSI 265' 25 0 LPSI 586' 51 I PCS(PORV) *693' **86 I I Subtotal 2741 231 0 Subtotal 1002 97 Total 3745 328

• 152' of new pipe installed during PORV modification in 4th quarter, 1989 will not be reverified by walkdown during 79-14 reverification, but the analyses will be reverified.

• • 33 supports installed or modified during PORV modifications in 4th quarter, 1989 will not be reverified by walkdown during 79-14 reverification, but the analyses will be reverified.

As indicated in the NRC's March 21, 1990 letter, one support was found to be missing after the modification was completed. This missing support, GC11-R854.1, was identified through preliminary walkdowns for the Safety-Related Piping Reverification Program, in order to assess scaffolding needs and ALARA planning for Phase I walkdowns.

Six supports; GC11-R854.1, GC11-H850.1, GC11-H805.2, GC11-H862, GC11-H869.1 and GC11-H878.1 were not to be removed or modified as part of the PORV/block valve system modification. In these supports, GC11-R854.1, was mistakenly removed during the modification. Consequently, this support was replaced and inspected. The remaining five supports are scheduled to be walked down during the Spring 1990 Maintenance Outage.

At the time the PORV/block valve modification was in progress, NRC concerns over the adequacy of past 79-14 walkdowns were known. As such, additional emphasis was placed on accuracy of quality verifications during post modification inspections. While Consumers Power Company strongly believes the quality of post modification walkdowns performed is acceptable, we are planning to confirm the quality of post modification inspections through verification of the as-built condition of two supports associated with the PORV/block valve modification. The reverification will be performed by OC0490-0322-NL04

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.,- ~ .Palisades Plant Safety-Rel Piping Reverification April 12, 1990 personnel performing independent quality walkdowns for the Safety-Related Piping Reverification Program.

--=----<r-----'~-<=>2-=--=L Richard W Smedley ~

Staff Licensing Engineer CC Administrator, Region III, USNRC NRC Resident Inspector - Palisades OC0490-0322-NL04