05000312/LER-1980-001, Forwards LER 80-001/03L-0

Forwards LER 80-001/03L-0

ML19257C670
Person / Time
Site:	Rancho Seco
Issue date:	01/17/1980
From:	Mattimoe J SACRAMENTO MUNICIPAL UTILITY DISTRICT
To:	Engelken R NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION V)
Shared Package
ML19257C671	List: 05000312/LER-1980-001, Forwards LER 80-001/03L-0 05000312/LER-1980-001-03, /03L-0:on 800102,while Performing Requirements of IE Bulletin 79-02,found Support Did Not Meet Criteria 2, Making HPI B Sys Inoperable.Caused by Design Error.Pipe Support Modified
References
NUDOCS 8001290583
Download: ML19257C670 (2)

LER-1980-001, Forwards LER 80-001/03L-0

Event date:
Report date:
3121980001R00 - NRC Website

text

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Q' SACRAMENTO MUNICIPAL UTILITY DISTRICT CJ 6201 S S suuo 95313; (916) 452-3211 January 17, 1980 3 A

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Engelken, Director Region V Office of Inspection & Enforcement u b ),

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S. Nuclear Regulatory Commission 1990 North California Boulevard Walnut Creek Plaza, Suite 202 Walnut Creek, California 94396 Re: Operating License DPR-54 Docket No. 50-312 Reportable Occurrence 80-1

Dear Mr. Engelken:

In accordance with Technical Specifications for Rancho Seco Nuclear Generating Station, Section 6.9.4.2b, and Regulatory Guide 1.16, Revision 4, Section C.2.b.2, the Sacramento Municipal Utility District is hereby submitting a thirty-day report of Reportable Occurrence 80-1.

On December 21, 1979, the District it. formed your office, via Bulletin 79-02 Supplemental Information, that as a result of an additional review of support drawings, an additional 89 pipe supports were identified as Seismic Category I supports. As stated in the letter, analysis and inspection were proceeding on those supports.

As in previous cases involving seismic analyses, the architect /

engineer, Bechtel Norwalk, was contracted to perform the analyses for the additional supports. On January 2, 1980, Bechtel informed the District that their analyses indicated that a particular support had a safety factor less than the minimum required by Bulletin 79-02.

The support, No. 3U-23628-4, is located on line No. 23628-6" GD.

This line is the suction side cross connection between the "B" HPI pump, P-238B, and the makeup pump, P-236.

Upon receipt of this information, the "B" High Pressure Injection System was declared inoperable. Work was started on nodification of the support to increase the safety factor to an acceptable value. The required modifications were near completion, within the 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br /> allowed for continued reactor operation per Techn' cal Specifications Section 3.3.2, when the District received notification of another support requiring modification. This notifi-cation was received on January 4, 1980.

Due to the location of the other support, a reactor shutdown was commenced. That occurrence was reported to your office via LER 80-2.

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1829 282

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Mr. R. H. Engelken Page 2 January 17, 1980 All modifications, which upgraded the safety factor of Support No. 3U-23628-4 to >5, were completed prior to returning to power following the January 4 shutdown.

Respectfully submitted,

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. Mattimoe Assistant General Manager and Chief Engineer JJM:HH: jim cs:

Director, MIPC (3)

Director, I&E (30) 1829 283