ML20205C381

Forwards Safety Evaluation Re Util Investigation of Static O-Ring Problem Noted During 860601 Reactor Feedwater Transient.Restart & short-term Operation Approved,Based on Licensee Proposed Actions & Test Results

ML20205C381
Person / Time
Site:	LaSalle
Issue date:	08/07/1986
From:	James Keppler NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III)
To:	Reed C COMMONWEALTH EDISON CO.
Shared Package
ML20205C386	List: ML20205C381 ML20205C405
References
NUDOCS 8608120319
Download: ML20205C381 (2)

Text

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. A nt 6 August 7, 1986 Docket No. 50-373 Docket No. 50-374 Commonwealth Edison Company ATTN: Mr. Cordell Reed Vice President Post Office Box 767 Chicago, IL 60690 Gentlemen:

On June 1, 1986 LaSalle Unit 2 experienced a reactor feedwater transient which caused water level to decrease below the low water level scram set point without the unit automatically shutting down. On June 2, 1986 I issued a Confirmatory Action Letter (CAL) which identified a number of actions you planned to accomplish and stated that unit 2 (and unit 1 if the problem were generic) could not be restarted without my concurrence.

As a result of your investigation into the June 1 event you embarked on a testing program to determine the scope of the problem with the Static-0-Ring switches, and determine which switches are acceptable for continued use to support plant operation. The testing program and its results were closely monitored by the NRC. The results of these tests have served as the bases of a Safety Evaluation Report (SER) issued on August 7,1986. A copy of this SER is enclosed. This report concludes that the licensee's proposed actions supplemented by the actions listed in the SER, and the test results of the switches provide an adequate basis for the restart and short term operation of LaSalle County Station Unit 2.

We met with you on July 9, 1986 to discuss actions taken by Commonwealth Edison Company in response to the June 2, 1986 CAL. We now consider all items listed in the CAL to be satisfactorily completed with regard to LaSalle Unit 2.

Based on the conclusions of the SER, your actions in response to the CAL and recommendations of the Staff, I concur that LaSalle Unit 2 may restart and operate in accordance with the provisions of the SER.

8608120319 860807 PDR ADOCK 05000373 S PDR

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F Mr. Jordell Reed August 7, 1986 This will also acknowledge receipt of your letter dated August 4,1986, in which you describe actions planned to minimize personnel errors during the startup and operation of Unit 2. My staff will be monitoring your actions closely during the restart and initial operation of the unit.

We will gladly discuss any questions you may have in this regard.

Sincerel Originab)W by drea G. Keppler James G. Keppler Regional Administrator

Enclosure:

Safety Evaluation Report (SER) cc w/ enclosure:

D. L. Farrar, Director of Nuclear Licensing G. J. Diederich, Plant Manager DCS/RSB (RIDS)

Licensing Fee Management Branch Resident Inspector, RIII Phyllis Dunton, Attorney General's Office, Environmental Control Division l

l RIII RIII RIII , RIII RIII Gu ond/cs Chris otimos s K er l 8/ 7 /86 8/~[/86 8/ 7 /86 8/ /86 8 7/86 i

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