ML20212E237

PNO-OSP-87-009:Ofc of Special Projects Completed Integrated Design Insp of ERCW Sys at Plant,Unit 2.Insp Involved multiple-discipline Review of Technical Adequacy of Design Documents & Calculations

ML20212E237
Person / Time
Site:	Sequoyah
Issue date:	09/14/1987
From:	Ebneter S NRC OFFICE OF SPECIAL PROJECTS
To:
References
PNO-OSP-87-009, PNO-OSP-87-9, NUDOCS 9711030112
Download: ML20212E237 (1)

Text

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9 W Vu?CL g f ] {b K fRELIMINARYNOTIFICATIONOFEVENTORUNUSUALOCCURRENCEPN0-OSP-87-09 This preliminary notification constitutes EARLY notice c,f events of POSSIBLE safety or public interest significance. The infonnation is as initially received without verification or evaluation, and is basically all that is known by the Region !! staff on this date.

FACILITY ( Tennessee Valley Authority Licensee Emergency Classification: 3 Sequoyah Unit 2 Notification of Unusual Event Docket No. 50-328 Alert ^

Site Area Emergency General Emergency X Not Applicable ,

~

SUBJECT:

COMPLETION OF THE INTEGRATED DESIGN INSPECTION AT SEQUOYAH NUCLEAR POWER PLANT The Office of Special Projects has completed iti Integrated Design Inspection (IDI) of the Esser.tial Raw Cooling Water (ERCW) system at TVA's Squoyah Nuclear Power Plant'. This in50ectlon involved a multiple-discipline review of the technical adequacy of design documents and calculations, the design interface and change controls, and the implementation of FSAR commitments.

TVA was advised of the iny ection results at an exit meeting on September 11, 1987, at the TVA offices in Knoxville, TN. In general, the staff concluded

- that, for most disciplines, with the correction of a number of less significant

() specific and generic deficiencies, the ERCW design and design control processes V were acceptable. However, because of significant deficiencies identified in the civil structuial areas of seismic analysis and assumptions, structural calculations, reinforced concrete design, and piping supports. TVA has been requested to condtet an additional review, using perscanel not involved in the original evaluaticns, to determine the full ger.aric implications of the staff finding;. This review would include a substantial sample of the major design features and desig.-construction interfaces for structures and components within the major safety-related buildings at Sequoyah. The impact that this additional review will have on the Sequoyah restart schedule cannot be determined at this time. However, some delay beyond the licensee's projected restart date of early November 1987 is expected.

TVA has inoicated that it has additional information not considered during the inspection that could mitigate the significance of the IDI findings and eliminate the need f6r some of the additional review. TVA expects to furnish the additional infonnation to the NRC this week.

The inspection report for the IDI inspectio;. will be issued by about November 6, 1987.

This PN is being issued because of the high level of interest in the IDI effort '

and because media interest in tnis matter has occurred.

This information is current as of September 14, Bd7.

Contact:

Stewart D. Ebneter - 492-9663 or Gene Imbro - 492-9664 p)

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N {, o C t:.<i 2 9711030112 870914 C/R Distribution: Chm, Cmrs ,

" S, GC, CA, 6, Historian, fNO-O 87-009 PDR SECY, Records. 9

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