PNO-III-86-070, on 860716,small Drip Wise Leak Observed on 8- Inch Suction Line to DHR Pump,Following Reactor Trip. Insulation Removed.Leak Due to Two Cracks Immediately Adjacent to Test Plug Weld

PNO-III-86-070:on 860716,small Drip Wise Leak Observed on 8- Inch Suction Line to DHR Pump,Following Reactor Trip. Insulation Removed.Leak Due to Two Cracks Immediately Adjacent to Test Plug Weld

ML20203D974
Person / Time
Site:	La Crosse File:Dairyland Power Cooperative icon.png
Issue date:	07/18/1986
From:	Boyd D, Guldemond W NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III)
To:
References
PNO-III-86-070, PNO-III-86-70, NUDOCS 8607240030
Download: ML20203D974 (1)

l PRELIMINARY NOTIFICATION OF EVENT OR UNUSUAL OCCURRENCE--PNO-III-86-70 Data July 18, 1986 g

This preliminary notification constitutes EARLY notice of events of POSSIBLE safety cr public interest significance. The information is as initially received without v:rification or evaluation, and is basically all that is known by the Region III staff on this date.

Facility: Dairyland Power Cooperative Licensee Emergency Classification:

LACBWR Notification of an Unusual Event Genoa, WI 54632 Alert Site Area Emergency Docket No: 50-409 General Emergency XX Not Applicable Subj ct: THROUGH-WALL CRACKS FOUND IN NON-IS0LABLE PORTION OF PRIMARY SYSTEM PIPING While in the hot shutdown mode following a reactor trip which occurred on July 16, 1986, a v ry small drip wise leak was observed on the 8" suction line to the decay Heat Removal Pump. The plant was then cooled down to permit the removal of the insulation from this line to determine the exact nature of this leak. When the insulation was remov;d the leak was found to be due to two small cracks immediately adjacent to a test plug weld, The cracks are 1/8 inch and 3/16 inch long cracks, one on each side of the plug, and they are oriented outward from the plug. This horizontal section of 8" piping is non-isolable.

Th2 licensee has contacted Southwest Research to come to the plant to investigate and cnalyza these pipe cracks. At this point, no repair plans or procedures have been

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R:gion III will follow the licensee's course of action.

Th2 State of Wisconsin will be notified.

This information is current as of 12 Noon (CDT), July 18, 1986.

CONTACT: D. Boyd Y

W. Guldemond FTS 388-5546 FTS 388-5574 DISTRIBUTION:

H. St. EDO NRR E/W Willste Mail: ADM:DMB Chairman Palladino PA IE NMSS D0T:Trans only Conn. Zech ELD OIA RES Comm. Bernthal AE0D Conn. Roberts Comm. Asselstine SP O AO Regional Offices ACRS SECY INP0 IW4 NSAC \:M CA RIII Resident' Office PDR Licensee: lSO (Corp. Office - Reactor Lic. Only) 9607240030 860718 Region III No-I!$86-070PDR Rev. November 1985