ML20079P685

Updated RO 83-06:evaluation of Discrepancies Between as- Built & Actual Design of Safety Injection Refueling Water Tank Support Structure Indicated Sufficient Capacity to Resist Loadings.Schedule for Mods & Design Review Submitted

ML20079P685
Person / Time
Site:	Palisades
Issue date:	04/28/1983
From:	Vandewalle D CONSUMERS ENERGY CO. (FORMERLY CONSUMERS POWER CO.)
To:	James Keppler NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III)
References
RO-83-06, RO-83-6, NUDOCS 8305100250
Download: ML20079P685 (2)

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.0 8 6 Consumers i Power Company

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e om - an w wome.a A . >== a. un meses . min vosesse April 28, 1983 Jemes C Keppler. Administrator Ragion III US Nuclear Regulatory Commissica 799 Roosevelt Road Glan Ellyn. IL 60137 DOCKET 50-255 - LICENSE DPR FALISADES FLANT - LICENSEE EVENT REPORT 83-06 (SIRW TANK SUPPORT STUCTURE DISCREFANCIES) UPDATE Censumera Fower Company reported a discrepancy between the actual configura-tion and the as-built design documents for the Safety Injection Refueling Water (SIRW) tank support structure in licensee event report 83-06 dated Fcbruary 17, 1983. Specifically, thirteen three-foot arlumra openings and one 26 inch by 38 inch opening are present in the concrete beams as compared to th3 mine openings identified on the es-built documentation. Our evaluation h00 concluded that although the existing condition is not in accordance with ths FSAR and ACI Code. sufficient capacity to resist specified loadings la maintained. Consumers Power Company also committed to pr, ovide specific information relative to the design and schedule for propos~ed modifications to bring the support structure into compliance with the Palisades Plant TSAR and ACI Code. The purpose of this letter is to provide Consumers Power Corpany's ochedule for modifications. Design details will be available for inspection cbcut June. 1983. Please identify your documentation needs so that a design review package can be prepared and forwarded to you when it becomes available.

Tho currently selected optimum design fix would involve relieving the stress in the SIRW tank support beams by draining most of the water from the SIRW tcak and filling the eight openings in the north-south beams of the support otructure with concrete and steel reinforcement bars to provide adequate shear ccpacity in the SIRW tank support beams. Steel reinforcing bars would be doweled into the been webs to transfer the shear force from the existing web to the repair. Conduit and piping presently routed through the foundation would be rerouted for accessibility. Engineering design efforts are presently cngoing and currently scheduled to be complete about June 1983. Subsequent offorta inclu3e review of the design by Consumers Power Company, the develop-ment of construction work I sckages, the performance of pre-outage work auch as the procurement of asterials, the fabrication and installation of piping and cupports on the building roof, preparation of electrical conduit and wiring for dismantling and rearranging and the cosmancement of core drilling in SIRW tcnk support beams to accommodate the aforementioned douel pf.ns. These preparatory activities are estimated to take about 12.veeks to complete. Actus!

OC0483-0012A-NLO2 B305100250 830428 PDR ADOCK 05000255 S PDR f d ),2 e

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. JCKeppler. Adninictrctor 2 Poliocoso Picat LER 83-06 UPDATE April 28, 1983 j sutage work is estimated to take 30 weeks to complete with concrete curing j eentrolling much of the critical path because the SIRW tank must be empty during that time.

Currently we have accelerated the start date of the 1983 Palisades refueling cuatage from October 15, 1983 to August 13, 1963. This is due to the cxcellent plant availability that Falisades has demonstrated in the past eight months (* 97%) and our extensive outage planning effort which har scheduled i oll outage work for the contigency of an early start by as muc? as 60 to 90 l d:ys.

j This refueling outage includes several projects and programs critical to the i continued safe operation of Palisades such as the 10-year Inservice Inspection including the mechanized reactor vessel exans and core barrel removal and casociated exams, installation of a third auxiliary feedwater pump, completion of the control room habitability modifications and upgrades, remedying the

leaking safety injection bottle check valves, completing the Systematic Evaluation Program modifications as previously committed in the Integrated

, Acsessment, and performing other significant activities including the afpping i

4 of a majority of the nuclear fuel, steam generator inspections, major turbine inspections and main electrical generator availability improvement modifica-tions. Although complete manpower loadings for all work are not now cvailable, it is estimated that there will be 1100 to 1400 personnel working en site during peak periods Of the outase.

Ts allow for more detailed planning of the actust implementation of the q proposed SIRW tank support structure design, to provide sufficient lead time

! for all materials, and to acconmodate evaluating alternative engineering j fixes, the merien of planning this fix for the 1985 Palisades refueling outage l ore extremely attractive.

! In light of these considerations and based upon our detailed analyses which indicate that the existing structure does not adversely affect the health and Delety of the public Consumers Power Company is proceeding with planning the

{ gIRW tank structural design fix as an integral part of the 1985 refueling i curage. In the interim, Consumers Power Company intends to conduct quarterly i inspections of the structure by a team of structural engineers. The purpose

! of this inspection will be to identify significant changes in structure that may have a potential for adversely affecting structural adequacy.

i l David J vandeWa33e (Signed)

I l David J Vandekalle i Gu21 ear Licensing Administrator I

i CC Director. Office of Nuclear Reactor Regulation Director, Office of Inspection and Enforcement NRC Resident Inspector - palisades i

l 1 OC0483-0012A-MLO2 f