United States Nuclear Regulatory Commission - Protecting People and the Environment



NRC Seal NRC NEWS

U. S. NUCLEAR REGULATORY COMMISSION

OFFICE OF PUBLIC AFFAIRS, REGION III

801 Warrenville Road, Lisle IL 60532

CONTACT:    Jan Strasma (630) 829-9663/e-mail: rjs2@nrc.gov
Angela Dauginas (630) 829-9662/e-mail: opa3@nrc.gov

NEWS ANNOUNCEMENT: RIII-97-24 March 4, 1997

NRC SPECIAL INSPECTION TEAM TO DISCUSS PRELIMINARY FINDINGS

ON CONTROL ROD INCIDENT AT ZION NUCLEAR POWER STATION

A Nuclear Regulatory Commission Augmented Inspection Team (AIT) will meet Friday with Commonwealth Edison Co. to discuss the team's preliminary findings on a February 21 incident at the Zion Nuclear Power Station involving improper control rod movements while Unit 1 was being shut down.

The meeting, which is open to public observation, will be at 1 p.m. Friday, March 7, at the Zion West Training Center, 505 Shiloh Blvd., Zion, Illinois.

At the time of the incident, Unit 1 was being shut down because of an inoperable pump in one of the plant's safety systems. The second unit at the site has been shut down since September for refueling and maintenance. Both units remain shut down.

In the February 21 incident, a control room operator was moving control rods into the reactor core to take the reactor to a very low thermal power level but not completely shut down. He inserted control rods farther than expected, however, and this caused the reactor to become subcritical (i.e. shutdown).

The operator then, without any direction from operations management, began withdrawing control rods with the intent of returning the reactor to a low power level.

Before the restart occurred, however, operations management directed that all control rods be inserted to comply with an NRC license requirement requiring a shutdown because of the inoperable pump.

This incident is of concern to the NRC because of the apparent failure of plant management to provide proper oversight of the shutdown activities and the apparent failure of the operator and management to clearly communicate and review plant conditions before beginning to withdraw the control rods to restart the reactor.

The seven-member Augmented Inspection Team began its site review on February 25. It has interviewed the operating staff and management involved and assembled a sequence of events. The team has focused its review on the management and functioning of the operating crew, the effectiveness of communications, and reactor power control activities.

The team will issue a written report in several weeks.

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