ML20028B729

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Forwards LER 82-032/03L-0.Detailed Event Analysis Encl
ML20028B729
Person / Time
Site: Summer South Carolina Electric & Gas Company icon.png
Issue date: 11/24/1982
From: Dixon O
SOUTH CAROLINA ELECTRIC & GAS CO.
To: James O'Reilly
NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II)
Shared Package
ML20028B730 List:
References
NUDOCS 8212030186
Download: ML20028B729 (2)


Text

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SOUTH CAROLINA ELECTRIC & GAS COMPANY Post orrice 7e4 COLuusiA, south CAROLINA 2h2[8" O. W. DixON, JR.

Vice P.sSIDENT November 24, 1982 suct .. o ...v o .

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3n s i . 4I Mr. James P. O'Reilly, Director U.S. Nuclear Regulatory Commission Region II, Suite 3100 101 Marietta Street, N.W.

Atlanta, Georgia 30303

SUBJECT:

~

Virgil C. Summer Nuclear Station Docket No. 50/395 Operating License No. NPF-12 Thirty Day Written Report LER 82-032

Dear Mr. O'Reilly:

Please find attached Licensee Event Report #82-032 for Virgil C. Summer Nuclear Station.

This Thirty Day Report is required by Technical Specification 6.9.1.13.(b) as a result of entry into Action Statement (a) of Technical Specification 3.11.1.3,

" Radioactive Effluents, Liquid Waste Treatment," on October 29, 1982.

Should there be any questions, please call us at your convenience.

Ver tr y yours, O. W. Dixon, Jr.

ARK:OND:dwf Attachment V. C. Summer A. R. Koon cc:

T. C. Nichols, Jr. H. Radin G. H. Fischer Site QA O. W. Dixon, Jr. C. L. Ligon (NSRC)

H. N. Cyrus G. J. Braddick H. T. Babb J. L. Skolds J. B. Knotts, Jr.

D. A. Nauman M. B. Whitaker, Jr. B. A. Bursey I&E (Washington)

W. A. Williams, Jr. Document Management Branch O. S. Bradham R. B. Clary INPO Records Center M. N. Browne NPCF File ,

c0TT' 8212030186 821124 O

PDR ADOCK 05000395 YN [/

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S pon

W I Mr. James P. O'Reilly LER No.82-032 Page Two November 24, 1982 DETAILED DESCRIPTION OF EVENT On October 29, 1982, with the Plant operating in Mode 2 during routine Auxiliary Operator rounds, it was discovered that the Nuclear Blowdown Monitor Tank was damaged. The hold down bolts were sheared; the pipe hangers were bent; the tank was " dished" on the bottom; and the manways were " bowed" and leaking. This is a non-safety, non-seismic tank which is required by the Offsite Dose Calculation Manual to be operable as part of the Liquid Waste Treatment System (Technical Specification 3.11.1.3).

PROBABLE CONSEQUENCES Plant releases could not be accomplished from the Nuclear Blowdown System via the normal path (Nuclear Blowdown Monitor Tank).

CAUSE(S) OF THE OCCURRENCE The cause of the occurrence was that the diaphragm located inside the tank apparently distorted such that it blocked off the tank overflow located below the diaphragm. Additionally, as the tank level was increased, the diaphragm " rolled up" inside the tank and blocked the remaining vent paths. As tank level was increased, air was compressed, thus causing the pressure in the tank to increase, resulting in damages as described above.

IMMEDIATE CORRECTIVE ACTIONS TAKEN The tank was immediately tagged out of service. On November 1, 1982, action was initiated to return the tank to service by installing lateral supports and grouting under the " dished" portion of the tank. Also, the diaphragm has been removed. At present, the tank is considered operable.

ACTION TAKEN TO PREVENT RECURRENCE A new diaphragm will be installed when procured. (Operation without the diaphragm only prohibits reuse of the blowdown water in the condensate system.) Engineering is evaluating the condition in order to identify any required modifications to ensure that all tank vent paths are not blocked and are available for pressure relief.