05000277/LER-1979-023, Forwards LER 79-023/01T-0

From kanterella
Jump to navigation Jump to search
Forwards LER 79-023/01T-0
ML19242D610
Person / Time
Site: Peach Bottom  Constellation icon.png
Issue date: 08/07/1979
From: Cooney M
PECO ENERGY CO., (FORMERLY PHILADELPHIA ELECTRIC
To: Grier B
NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
Shared Package
ML19242D611 List:
References
NUDOCS 7908150506
Download: ML19242D610 (3)


LER-1979-023, Forwards LER 79-023/01T-0
Event date:
Report date:
2771979023R00 - NRC Website

text

.

PHILADELPHIA ELECTRIC COMPANY 2301 M ARKET STREET P.O. 3CX 8699 PHILADELPHs A. PA.19101 (215)841-4000 August 7,

1979 Mr. Boyce H.

Grier, Director office of Inspection and Enforcement Region I United States Nuclear Regulatory Commission 631 Park Avenue King of Prussia, Pennsylvania 19406

Dear Mr. Grier:

SUBJECT:

Licensee Event Renort Narrative Description The following occurrence was reported to Mr. Caphton, Region I,

Office of Inspection and Enforcement on July 25, 1979.

Referencs Docket Number 50-277 50-278 Report No:

LER 3-79-23/1T Report Date:

August 7,

1979 Occurrence Date:

July 24, 1979 Facility:

Peach Bottom Atomic Power Station R.D.

1, Delta, PA 17314 Technical Specification Reference.

Technical Specification 6.9.a(9) requires reporting

" performance of structures, systems, or comp onents that require remedial action or corrective measures to prevent operatior

'n a

manner less conservative than assumed in the accident ana'

.ie in the safety analysis report..."

c

.nra d,v'(Lib' El -.

W 5t \\

7908150 g

~

Mr. Boyce H.

Grier Page 2 August 7,

1979 LER 3-79-23/1T Descriotion of the Event:

The continuing seismic anchor inspection program being performed in response to IE Bulletin 79-02 identified a failure i

of an anchor support (as defined in test criteria) on the emergency service water piping in the Unit 3

'B' Residual Heat Removal (RHR) room.

This inspection identified one bolt on a four anchor support nlace which would not torque properly.

Additionally, one bolt was found with a cracked hcad.

The failure of these two bolts on one support plate has been evaluated as a support failure.

Consequences of Event The suppart plate anchors which failed to torque properly were part of an emergency service water piping support.

The emergency service water line (3 inch diameter) is associated with room coolers in the Unit 3

'B' RHR room.

Failure of the piping during a seismic event could lead to flooding of one RHR room.

Becaus< redundant pumps and back up ECCS systems are available, the safety significance is considered minimal.

i

Cause of Event

Investigation indicates the most probable cause of failure for these anchors was improper installation.

Corrective Action

The two test failed anchor bolts have been replaced with wedge type bolta.

All four bolts in this support were satisfactorily torque tested.

Corrective action has been completed.

The anchor inspection program as required by IE Bulletin 79-02 is continuing and will serve to ensure that all seismic anchors are satisfactorily installed.

L r Tro G 0 U %s>'s

N Mr. Boyce H.

Crier Page 3

' August 7,

1979 LER 3-79-23/IT Previous Similar Occurrencess 3-79-19/1T, 2-79-32/IT, 2-79-35/?T, 2-79-33/1T Yours truly,

't

/

I l' '/L-t{ >

[ M.,'Jt Cooney Superintende t C'e n e r a t i on Division-Nuclear Attachment cc:

Director, NRC - Office of Inspection and Enforcement Mr. Norman M.

Haller, NRC - Office of Management &

Program Analysis 50G353