ML093620882

Forwards LER 81-011/01T-0

ML093620882
Person / Time
Site:	Indian Point
Issue date:	05/22/1981
From:	O'Toole J Consolidated Edison Co of New York
To:	Grier B NRC/OE, NRC/OI/RGN-I/FO
Shared Package
ML093620883	List: ML093620882 ML20004F374
References
NUDOCS 8106180250
Download: ML093620882 (3)

Text

John 0. 0'1oole Vlck. Pr eh;Icjl Consolidated Edison Company of New York, Inc.

4 Irving Place. Now York. NY 10003 "elephone (212) 460-2533 I< I '.

May 22, 1981 Re: Indian Point Unit No. 2 Docket No. 50-247 LE R- 8 1- 011/l" 0 OJT Mr. Boyce H. Grier, Director Office of Inspection and Enforcement Region I U. S. Nuclear Regulatory Commission 631 Park Avenue King of Prussia, Pa 19406

Dear Mr. Grier:

The attached Licensee Event Report LER-8-0ll/Q-3, 01l

-0 is hereby sub mitted in accordance with the requirements of Technical Specification 6.9.1.7. This event is of the type described in Technical Specification 6.9.1.7.1.i.

Three copies of this letter and the attachment are enclosed as required.

Ve truly yours,

/77 attach.

cc: Mr. Victor Stello, Jr., Director (30 copies)

Office of Inspection and Enforcement c/o Distribution Services Branch, DDC, ADM Washington, D. C. 20555 Mr. William G. McDonald, Director (3 copies)

Office of Management Information and Program Control U. S. Nuclear Regulatory Commission Washington, D. C. 20555 Mr. T. Rebelowski, Resident Inspector U. S. Nuclear Regulatory Commission AoO'~

P. 0. Box 38 Buchanan, N. Y. 10511

/1'>

8I aS0 -a50

LICLNSLE LVLN I HLKPUH I CONTROL BLOCK: I (PLEASE PRINT OR TYPE EQUI ED INFORMATION)

M0 1] N1 Y1 1lpl~ Is1_2]01,,2 o c -I0 I l I li 1 1 l ! 14 11l l l lG) 7 8 9 LICENSEE CODE 14 15 LICENSE NUMBER 25 26 LICENSE TIfe 30 57 CAT 58 CON'T RE F11 1

-- SEPORT L 1J@I61 0 51 0DOCKET l0o o NUMBER12 I 4I 711o I5 I 01DATE8 ! 741@ 1 75 o 1 51 212 1Il 110 REPORT DATE 80 7 8 60 68 69 EVENT EVENT DESCRIPTION AND PROBABLE CONSEQUENCES 0 O 2 I During inspection of service water pump discharge pipinapits were

• 6-3 I observed on the exterior surface. Non-destructive examinat-ion nf the O 4 I pits indicated that the pipe wall thickness under four small plif wasi O 5 less than the minimum wall thickness required to meet seismic design

[O6 J criteria, (0.135 inches). Possible consequences could nave been the O I eventual development of small pinhole leaks with no degradation in the 081 operability of the service water system.

7 8 9 80 SYSTEM CAUSE CAUSE COMP. VALVE CODE CODE SUBCODE COMPONENT CODE SUBCODE SUBCODE 9] IWIA(I W@ LD IFIIIPIE Ixi xl L1J @6, 7 .8 9 10 11 12 13 18 19 20 SEQUENTIAL OCCURRENCE REPORT REVISION LE R/R0 EVENT YEAR REPORT NO. CODE TYPE NO.

17 REPORT 18 11 L-J Lu I 11111 L ji LT Li LOi

.. .. NUMBER 226 . 231 - 28 29. 30 .... .. .... ... 32 ACTION FUTURE EFFECT SHUTDOWN f' ATTACHMENT NPRD-4 PRIME COMP. COMPCNENT TAKEN ACTION ON PLANT METHOD HOURS (22 SUBMITTED FORM SUB. SUPRLIER MANUFACTURER 33 B11cI I 34 L@

35 I.z10 36 IWo I uI ol 1 WO 37 40 x1jIJN 41 .42 43 I xl1 9 1910 44 47 CAUSE DESCRIPTION AND CORRECTIVE ACTIONS 44

[ I External corrosicn caused four pits to be formed in the service water W I pumps discharge piping which resulted in local areas below minimum walli 2I thickness. The areas were sand blasted, a patch was welded over each 1 3 pitted area and the entire surfaces of the pipes repainted to prevent I

'- 4 I further corrosion.

7 8 9 80 FACILITY METHOD OF 80 STATUS %POWER OTHER STATUS DISCOVERY DISCOVERY DESCRIPTION @

7 8 9 LJ @ I ol 10 0 o101 12 13 N/A 44 1 LcUI Special test of depth of pits 45 46 80 I

ACTIVITY CONTENT_

RELEASED OF RELEASE AMOUNT OF ACTIVITY LOCATION OF RELEASE @

7 16 8 9 LI 51LII 10 11 N/A ,N/A.I 44 45 80 PERSONNEL EXPOSURES NUMBER TYPE DESCRIPTION 7

17Z, 8 9 L olD 11 12 13 N/A - I 80 PERSONNEL INJURIES NUMBER DESCRIPTION 7 8 9 11 1 80 LOSS OF OR DAMAGE TO FACILITY IYPE DE SCRI PTION \~~ ~

7 ELJBI 8 9 10 N/A 80 PUBLICITY NRC USE ONLY ISSUED DESCRIPTION @

10 68 69 80; NAME OF PREPARER PHONE:

ATTACHMENT I Docket No. 05000247 Consolidated Edison Company LER 81-01.1/03L-0 of New York, Inc.

Indian Point Unit No. 2 While in cold shutdown the service water piping in the pump pit was sand blasted to remove surface corrosion.

Visual inspection of the cleaned pipe showed a total of seven (7) pits had formed on three of six service water pump discharge lines.

The depth of the pits and surrounding wall thickness were measured pipe pit gage and an ultrasonic meter respectively. using a The remain ing wall thickness under each pit was then calculated using the measured values.

Using an allowable wall thickness of 0.135 inches, based on seismic considerations, it was found that which was there were four pits which were below the value. These wall thicknesses were: Line No. 23, 0.060 inches; Line No. 24, 0.060, 0.105 and 0.125 inches.

The cause of the pitting is believed to have

._corrosion resulting- from thedamnpconditions been external found-in the pump pit. A patch was welded over each pitted area and the entire surfaces of the pipes repainted to prevent further corrosion.

The size and small number of pits did not reduce the ability of the piping to withstand a design basis seismic event. Had one or more pits developed into through holes, the result would have been "pinhole" leaks which would not have significantly degraded the operability of the system.