An accident at Entergy’s Arkansas Nuclear One station near Russelville, Ark., left one worker dead and eight injured Sunday morning. The accident involved the 836-MW Unit 1, which was in a refueling and maintenance outage at the time. The 987-MW Unit 2 was operating but tripped offline and was reported to be in a stable mode. No nuclear material was released.

The accident occurred at 7:50 a.m. Central time after a lift device failed as workers were moving the 500-ton Unit 1 main turbine generator stator, Entergy said in a statement to the Nuclear Regulatory Commission (NRC). This caused a loss of all off-site power to Unit 1.

The accident caused Unit 2 to trip, with all its reactor control rods inserted successfully. Entergy said the Unit 2 core was being cooled by natural circulation and that decay heat was being removed by steam dumps to the atmosphere. The plant declared an unusual event due to damage to a breaker cubicle, but it exited the event Sunday evening after stabilizing power supplies to both units. Power to Unit 1 was being supplied by emergency diesel generators. Unit 2 was being powered by emergency diesel generators and off-site power.

The accident resulted in one death, identified by the county coroner as Wade Walter, 24. Eight others were injured. Six employees were treated at local hospitals and released. Two others were hospitalized with injuries, Entergy said.

As many as 100 people were involved in the stator generator move at the time of the accident, Jeremy Browning, site vice president, told local news outlets. "We are still performing an investigation, gathering facts, and do not have any additional information as to the cause," Browning was quoted as saying by KTVH television news.

The utility notified the State of Arkansas, local authorities, the Occupational Health and Safety Administration (OSHA), and the NRC Resident Inspector after the accident. News reports said that OSHA sent investigators to the site on Monday. The NRC said it sent two inspectors to the plant to assist its on-site Resident Inspector.

Both units are pressurized water reactors supplied by Babcock & Wilcox (Unit 1) and Combustion Engineering (Unit 2). Westinghouse supplied the turbine generator for Unit 1 and General Electric for Unit 2. Unit 1 entered commercial service in December 1974 and is licensed to operate until 2034. Unit 2 entered commercial service in March 1980 and is licensed to operate until 2038.

Sources: Entergy, KTVH

David Wagman, Executive Editor (@EPContentDirect)

This story was first published April 2.