ML17195A952

Safety Evaluation Approving Util plant-unique Analysis Rept on Pool Dynamic Loads

ML17195A952
Person / Time
Site:	Dresden
Issue date:	09/18/1985
From:	Office of Nuclear Reactor Regulation
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Shared Package
ML17195A951	List: ML17195A950 ML17195A952 ML17195A953 ML20204G817 ML20205B027
References
NUDOCS 8509230618
Download: ML17195A952 (2)

Text

e UNITED STATES NUCLEAR REGULATORY COMMISSION e

WASHINGTON, D. C. 20555 SAFETY E\IALUll.TION RY THE OFFICE OF NUCLEAR REACTOR REGULAi'-ION RELATED TO MARI<'. I CONTAINMENT LONG-TERM PROGRAM POOL DYNAMIC LOADS* REVIEW COMMONWEALTH EDISON COMPANY DOCKET NOS. 50-237/249

1.0 INTRODUCTION

In July 1980, the staff issued a report, NUREG-0661, "Safety Evaluation .

Report, Mark I Containment Long-Term Program," to address the NRC acceptance criteria for the Mark I containment Long-Term Program, which are intended to establish design basis loads that are appropriate for the anticipated life of each Mark I BWR facility, and to restore the originally intended design safety margins for each Mark I containment system.

Since the issuance of NUREG-0661, the Mark I owners submitted additional reports in which they provided additional justification for the adequacy of: (1) the data base for specifying torus wall pressure during condensa-tion oscillations; (2) the consideration given to asyrrnnetric torus loading during condensation oscillations; and (3) the effect of fluid compressibility in the vent system on pool-swell loads. As a result of the staff's and its consultant's (Brookhaven National Laboratory) evaluation of these reports, Supplement 1 to NUREG-0661, dated August 1982, has been issued.

2.0 EVALUATION Commonwealth Edison Company (CECo) submitted a Plant Unique Analysis Report (PUAR) on the pool dynamic loads for the Dresden Nuclear Power Station, Unit Nos. ?. and 3 Mark I containment. This report provides a description of the specific application of the generic Mark I pool dynamic loads and methods for Dresden, Units 2 and 3 and the plant unique loads used in assessing the cap~bility of the containment and components to accommodate the pool dynamic loading phenomena. The Brookhaven National Laboratory (BNL) was contracted to review the PUAR f~r compliance with the staff's acceptance criteria and to evaluate the acceptability of any proposed alternative load specification.

A Summary of the BNL review and status~for each of the pool *dynamic loads is presented in the attached report titled "Technical Evaluation of the Dresden Nuclear Generatin9 Station, Units 2 and 3 Plant *unique Analysis Report." As indicated in the report, CECo has adopted all but a few of the generic criteria. For those few exceptions alternative criteria were proposed. The BNL evaluation of these criteria is included in the attached report. Based on its review, the staff endorses the BNL evaluation and conclusion.

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3. 0 COM CL US IONS The staff has completed an assPssment of Dresden, Units 2 and 3~against generic acceptance criteria contained in NUREG-0661 and its supplement, and has also reviewed thnse fe~ areas where alternative criteria have been proposed. In addition, the staff has completed its review of those areas where additional information was relegated to the plant unique review. In each of these areas the staff has concluded that the pool dynamic loads utilizP.rf by CECo are c0nservative and, therefore, acceptable.

4.0 ACKNOWLEDGEMENT Principa~ Contributor: F. Eltawila Date: September 18, 1985.

Attached: Technical Evaluation, dated September 1984, prepared by BNL