ML19242A374

Forwards LER 79-035/01T-0

ML19242A374
Person / Time
Site:	Peach Bottom
Issue date:	07/20/1979
From:	Cooney M PECO ENERGY CO., (FORMERLY PHILADELPHIA ELECTRIC
To:	Grier B NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
Shared Package
ML19242A375	List: ML19242A374 ML19242A386
References
NUDOCS 7908010536
Download: ML19242A374 (1)

Text

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PHILADELPHIA ELECTRIC COMPANY 2301 MARKET STREET P.O. BOX 8699 PHILADELPHIA. PA.19101 (215)841-4000 July 20, 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

SUBJECT:

Licensee Event Report Narrative Description The following occurrence was reported to Mr. Greenman, Region I, Office of Inspection and Enforcement on July 9, 1979.

Reference:

Docket Number 50-277 50-278 Report No: LER 2-79-35/1T Report Date: July 20, 1979 Occurrence Date: July 6, 1979 Facility: Peach Bottom Atomic P er Station R.D. 1, Delta, PA 173t4 Technical Soecification

Reference:

Technical Specification 6.9.a(9) requires reporting

" performance of structures, systems, or components that require remedial action or corrective measures to p revent operation in a manner less conservative than assumed in the accident analysis in the safety analysis report..."

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Mr. Boyce H. Grier Page 2 July 20, 1979 LER 2-79-35/IT Description of the Event:

The continuing scismic anchor inspection program being performed in response to IE Bulletin 79-02 identified 18 shell type anchors which failed to torque properly. These anchors were all associated with horiz ontal supp orts on the emergency cooling water piping on the upper deck of the emergency cooling tower structure.. These were distributed as follows:

1 anchor plate contained 4 of 4 anchor test failures 4 4 anchor plates contained 2 of 4 anchor test failures 8 6 anchor plates contained 1 of 4 anchor test failures _6 TOTAL 18 Consequences of Event:

The horizontal anchars on the upper deck of the emergency cooling tower structure support emergency cooling water piping which is used only during unusual events such as flood and loss of Conowingo Pond. This piping does not effect the performance of the emergency service water or high pressure service water syctems. If such unusual environmental events should occur, the distribution'of the above anchors is such that it is highly unlikely the piping integrity could be affected by these anchor test failures. Safety significance is therefore considered to be ninimal.

Cause of Event:

Investigation indicates the most probable cause of test failure for these anchors was improper installation. The anchors were installed in the grout beneath the support plate instead of the structural concrete.

Corrective Action:

As e a ci. anchor test failure was identified, new anchors (vedge type) were immediately installed in the structural concrete and ,uccessfully torqued to proper values.

The inspection program was performed in accordance with an approved procedure which requires testing of at least one bolt in each anchor plate. If the first bolt is successfully tested, no further testing on that anchor plate is required. If the first bolt tested fails, all other bolts on the anchor plate are then tested. This program identified 13 test failures discussed above.

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Mr. Boyce H. Grier Page J July 20, 1979 LER 2-79-35/1T Because of the significant number of test failures, the remaining anchor bolts associated with the 47 horizontal supports in this area were tested during the week of July 9. This testing program identified five more improperly torqued tolts. Of the 188 b olt s tested, a total of 18 bolts did not meet the test criteria. These 18 anch or bolts were replaced and successfully tested by July 10, 1979.

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.

Yours truly,

. . Coon y Su erinten ent Generation Division-Nuclear Attachment ec: Director, NRC - Office of Inspection and Enforcement Mr. Norman M. Haller, NRC - Office of Management &

?rogram Analysis

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