ML20147F277

Responds to 781130 Ltr Re Hydraulic Snubber Surveillance Program.Cause of Bergen-Paterson Snubber Failure Due to Mishandling During Installation

ML20147F277
Person / Time
Site:	Rancho Seco
Issue date:	12/08/1978
From:	Reid R Office of Nuclear Reactor Regulation
To:	Mattimoe J SACRAMENTO MUNICIPAL UTILITY DISTRICT
References
NUDOCS 7812210391
Download: ML20147F277 (2)

Text

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.g*g NUC1. EAR REGULATORY c0MMISslON .

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• ..e Docket No. 50-312-

- Mr.'J.J.Matti5 toe Assistant General Manager and ,

Chief. Engineer Sacramento Municipal Utility District 6201 S Street P. O. Box 15830 Sacramento, California 95813

Dear Mr. Mattimoe:

This'is in reference to your letter of November 30, 1978, concerning hydraulic snubber surveillance recently performed at the Rancho Seco Nuclear Generating Plant. Regarding this matter, please be advised that on the basis of our review of your submittal, we conclude that-the cause of failure of the Bergen-Paterson snubbers was due to mishandling during installation. This mishandling was a result of the tendency of these units to grow after adjustment of their length in a test

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stand. l 1

Because the mishandling was limited to the Bergen-Paterson units, as confirmed in discussions with you, and because no failures were discovered in the Grinnell units that were tested, we concur that Accordingly,the l mechanism of failure is unique to the Bergen-Paterson units.  ;

we further concur, pursuant to facility Technical Specification 4.14,4, that Grinnell snubbers need not be tested during the current follow-on tests.

Sincerely, g h /h Y.

RIbertW.Reid, Chief Operating Reactors Branch 44 Division of Operating Reactors cc: .See next page

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Sacramento Municipal Utility District -

• 1 cc: David S. Kaplan, Secretary and i General Counsel i G201 S Street j Post Office Box 15830 i Sacramento, California 95813 (

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j Mr. Robert B. Borsum ._

Babcock & Wilcox .

Nuclear Power Generation Division Suite 420, 7735 Old Georgetown Road Bethesda,_ Maryland 20014 Business and Municipal Department Sacramento City-County Library 828 ! Street Sacramento, California 95814

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