05000278/LER-1979-038, Forwards LER 79-038/01T-0

Forwards LER 79-038/01T-0

ML19256F346
Person / Time
Site:	Peach Bottom
Issue date:	12/06/1979
From:	Cooney M PECO ENERGY CO., (FORMERLY PHILADELPHIA ELECTRIC
To:	Grier B NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
Shared Package
ML19256F347	List: 05000278/LER-1979-038, Forwards LER 79-038/01T-0 05000278/LER-1979-038-01, /01T-0:on 791120,during Review of Surveillance Test,Two MSIVs in a Steamline Closed in Times Shorter than Specified in Tech Specs.Caused by Operator Not Recognizing Fast MSIV Closure Time.Operator Procedure Revised
References
NUDOCS 7912180586
Download: ML19256F346 (2)

LER-1979-038, Forwards LER 79-038/01T-0

Event date:
Report date:
2781979038R00 - NRC Website

text

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PHILADELPHIA ELECTRIC COMPANY 2301 M ARKET STREET P.O. BOX 8699 PHILA DELPHI A. PA.19101 (2151041 4000 December 6,

1979 Mr. Boyce H.

Grier, Director l

Office of Inspection and Enforcement Region I United States Nuclear Regulatory Commission 631 Park Avenue King c.' Prussia, Pennsylvania 19406

Dear Mr. Grier:

SUBJECT:

Licensee Event Report Narrative Description The following occurrence was reported to Mr. Greenman, Region I,

Office of Inspection and Enforcement on November 21, 1979.

i

Reference:

Docket Number 50-278 I

Report No:

LER 3-79-38/1T Report Date:

December 6,

1979 Occurrence Date:

November 21, 1979 Facility:

Peach Bottom Atomic Power Station R.D.

1, Delta, PA 17314 Technical Specification Reference:

Technical Specification 6.9.2.a(2) requires reporting

" operation of the unit or affected systems when any parameter or operation subject to a limiting condition is less conservative than the least conservative aspect of the limiting condition for operation established in the t ech nical s p e cif ica tions. "

Description of the Event:

l Review of a surveillance test completed on N ove mb e r 17, 1979, reve a le d that the two MSiV's in the "A" steamline (80A and i

86A) closed in times shorter than specified in Tech Spec Table 3.7.1.

Because the individual who p erf ormed the surveillance test failed to recognize that the tw o MS IV's closed too q uick ly,

the unit operated in a degraded mode until 11/20/79 Since discovery of the event, the reactor has been operating at 1608 247 7 012180 3r5M

Mr. Boyce H.

Grier Page 2 D e c e mb e r 6,

1979 LER 3-79-38/IT approximately 75 % p ower with the "A" MSIV's closed in accordance with Tech Spec 3.7.D.2.

Consequences of Event:

Faster closure than specified increases the p res su re reached during a main steamline isolation.

The fastest valve closed in 1.6 to 1.7 seconds, but the average is ola tion time for all 4

'. 0 ~. e s was more than 2.8 seconds.

Because the t ransient analysis shows no significant effects for a 3 second is ola tion, it is believed that a 2.8 second isolation should have minimum effect and be within the conservatism of the analysis.

Cause of Event

The delay in recognizing that the "A" MSIV isolation valves closed too fast was caused by pers onnel error and a contributing factor was procedural format.

The fast closure of the valves is presently attributed to malfunctioning hydraulic valve operators.

Corrective Action

Upon discovery of the results, react or p ower was reduced to 757. and the valves in the "A" steamline were closed.

The hydraulic valve op e ra t o rs that caused the problem will be repaired or adjusted during a future outage.

The importance of this incident has been stressed to the responsible individual and the appropriate procedure has been revised to avoid recurrence.

Y ou rs truly, ffY i

[

I' 'f(!Kx.c i--

J. Cooney g/

1.

Gd[n e ra ti on S perintendent Division-Nuclear Attachment l

cc:

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

Haller, NRC - Office of Management &

Program Ana ly s is i

f 1608 248 9