U-600890, Ro:On 870322,containment Isolation Occurred on Instrument Air Sys During Surveillance of ECCS Reactor Water Level Channel Functional Checklist.Cause Not Stated.Reactor Shut Down

Ro:On 870322,containment Isolation Occurred on Instrument Air Sys During Surveillance of ECCS Reactor Water Level Channel Functional Checklist.Cause Not Stated.Reactor Shut Down

ML20204H314
Person / Time
Site:	Clinton
Issue date:	03/23/1987
From:	Spangenberg F ILLINOIS POWER CO.
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
U-600890, NUDOCS 8703260608
Download: ML20204H314 (2)

Text

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F U-600890 L30-87(03-23)-L 1A.120 ILLINDIS POWER COMPANY CLINTON PCnER STAflON. P o. BOX 678. CLINTON. ILLINOIS 61727 March 23, 1987 Docket No. 50-461 U.S. Nuclear Regulatory Commission Document Control Desk Washington, D.C. 20555

Subject:

Clinton Power station Notification of Unusual Event

Dear Sir:

Please find attached a su;amary report of the " Notification of Unusual Event (NOUE)" which occurred at Clinton Power Station on March 22, 1987.

This summary report is submitted pursuant to Appendix 1 of NUREG-0654 (Revision 1) and Table 4-1 of the Clinton Power Station Emergency Plan.

If you have any questions concerning this summary report, please contact me.

Sincerely yours, F. A. Spangenberg Manager - Licensing and Safety DW/bsa Attachment cc: Regionni Administrator, Region III, USNRC W. Snell, Chief Emergency Preparedness Section B. L. Siegel, NRC Clinton Licensing Project Manager NRC Resident Office Illinois Department of Nuclear Safety Ur br*Cb 1 1/ h* tf))Sf$ b 'l 0703260600 Dil 070323 ADOCK 0500 1 ph fg g/g ggd I I l

o Clinton Power Station Notification of Unusual Event (NOUE)

On Sunday, March 22, 1987, at approximately 0425, with the reactor previously at less than 1 percent power (Mode 2), a Notification of Unusual Event (NOUE) was declared per Emergency Plan Implementing Procedure EC-02, Emergency Classifications. This procedure requires a Notification of Unusual Event to be declared for conditions which involve other than normal controlled shutdown. The events which led up to the NOUE are as follows:

Operations personnel were performing a surveillance per procedure CPS No. 9030.01C016. ECCS Reactor Water Level 1 B21-N691A(E B,F) Channel Functional Checklist, when containment isolation occurred on the instrument air system.

When instrument air system containment isolation valves shut, loss of instrument air pressure within the Containment Building resulted in a loss of air to the scram pilot valves causing control rods to drift inward.

The Control Room Operator noticed the movement of the control rods and placed the reactor mode switch in the Shutdown position at 0415 hours0.0048 days <br />0.115 hours <br />6.861772e-4 weeks <br />1.579075e-4 months <br />. A complete manuni reactor scram occurred.

At 0425 hours0.00492 days <br />0.118 hours <br />7.027116e-4 weeks <br />1.617125e-4 months <br />, with the reactor shutdown, a Notification of Unusual Event was declared. Notification to the State of Illinois was performed at 0439 hours0.00508 days <br />0.122 hours <br />7.258598e-4 weeks <br />1.670395e-4 months <br />. Notification of the Nuclear Reguintory Commission Incident Response Center was performed at 0519 hours0.00601 days <br />0.144 hours <br />8.581349e-4 weeks <br />1.974795e-4 months <br />. At 0535 hours0.00619 days <br />0.149 hours <br />8.845899e-4 weeks <br />2.035675e-4 months <br />, after the reactor was shut down and in a stabic condition, the NOUE was terminated and notifications to the State of Illinois and the Nuclear Regulatory Commission Incident Response Center were made.