ML20024E911

Updated LER 83-097/03X-1:on 830720,reactor Water Cleanup Auto Isolation Occurred.Caused by Delta Temp Channel B Indicating Temp Above Trip Point Limit.Investigation continuing.W/830830 Ltr

ML20024E911
Person / Time
Site:	Grand Gulf
Issue date:	08/30/1983
From:	Cathey D, Dale L MISSISSIPPI POWER & LIGHT CO.
To:	James O'Reilly NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II)
References
AECM-83-0499, AECM-83-499, LER-83-097-03X, LER-83-97-3X, NUDOCS 8309070196
Download: ML20024E911 (3)

Text

r:RC roRuaes Update Report - Previous Report Date 8/19/83 U.S. NUCLEAR CEIULATORY COAmelSS40N

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67 CAT 68 CON'T o i 7 8 E %esl 01 315101 Ol OOCKfr OlNUMSER 41 1 l 6hE 017 S l 21 OloA73Ed 3 M@ O l 813i EVE 81T 75 REPomTOArE018 l 3l@ 80 EVENT DESCRWTION AND Penem E CON 850UENCES h o 2 IDn Julv 20, 1993. a RWCU auto isolation occurrcJ. At the time. RWCU wael o a Ibeing used as the alternate method of reactor coolant circulation j o e leursuant to Action (2) of T.S.3.4.9.2 due to equipment failures in the i o s IRHR system. RWCU was back in operation within 30 minutes by placing the i o 6 lRWCU ISOL LOGIC "B" BYPASS switch in bypass. This had no affect on the i fo f7] lhealth and saf ety of the public and did not constitute a threat to plantl 1 o 181 Leaf ety. An update report is expected to be submitted by August 30, 1984 1

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Estataddu P. O. B O X 16 4 0, J fp N. MISSISSIPPI 39205 August 30, 98$ 4 g ,.

NUCLEAR PRooUCTION DEPARTMENT U. S. Nuclear Regulatory Commission Region 11 101 Marietta St., N.W., Suite 2900 Atlanta, Georgia 30303 Ai.tantion: Mr. J. P. O'Reilly, Regional Administrator

Dear Mr. O'Reilly:

SUBJECT:

Grand Gulf Nuclear Station Unit 1 Docket No. 50-416 License No. NPF-13 File 0260/L-835.0 Update Report - RWCU Auto Isolation Occurs LER 83-097/03 X-1 AECM-83/0499 This letter cubmits an update to a previous report submitted on August 19, 1983. The event for which the report was submitted occurred on July 20, 1983, when a RWCU auto isolation occurred. At the time, RWCU was being used as an alternate method for reactor coolant circulation pursuant to Action (2) of Technical Specification 3.4.9.2 due to equipment failures in the RHR System. The RWCU system was returned to operation within thirty (30) minutes by placing the RWCU Isolation Logic "B" Bypass Switch in bypass. This was reported pursuant to Technical Specification 6.9.1.13.b.

In our original letter submitted August 19, 1983, we incorrectly stated on the LER form that Action (2) of Technical Specification 3.4.9.2 was entered due to equipment failures in the RWCU System. It should have said due to equipment failures in the RHR System. Attached is revised LER 83-097/03 X-1.

Yours truly,

. 3

% L. F. Dale Manager of Nuclear Services EBS/SHH: sap Attachment cc: (See Next Page)

COY fcVb Member Middle South Utilities System j'1,f ll

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AECM-83/0499 MISSISSIPPI POWER O LIZHT COMPANY a

cc: Mr. J. B. Richard (w/a)~

- Mr. R. B. McGehee ' (w/o) l Mr. T. B. Conner (w/o)

<- lie. G. B. Taylor (w/o)

Mr. Richard C. DeYoung, Director (w/a)

Office.of Inspection & Enforcement U. S. Nuclear Regulatory Commission Washington, D. C. 20555 Document Control Desk (w/a)

U. S. Nuclear Regulatory Commission Washington, D. C. 20555 d

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