Warning to the power industry

Two and a half years after an accident in a nuclear power plant killed five workers and injured six others, police have sent up papers to public prosecutors on five employees of Kansai Electric Power Co. and an employee of the utility's subsidiary. It is rare for police to pursue criminal responsibility in the operation of a nuclear power plant.

Although KEPCO's management is not criminally accused, it should seriously examine whether the company truly gives priority to safety and whether its safety system really works. The police action also should serve as a warning to the entire power industry since it was recently found that Tokyo Electric Power Co. falsified data or committed other irregularities in connection with the state inspection of nuclear power plants on 199 occasions.

On Aug. 9, 2004, a worn pipe in the secondary cooling system of the No. 3 reactor at KEPCO's Mihama nuclear power plant in Fukui Prefecture ruptured, releasing nonradioactive burning-hot steam, which killed the five subcontract workers. Police said the six criminally accused employees were in a position to know that the pipe had not been examined since operations began in 1976, yet had not taken proper actions.

The discovery July 1, 2004, that a pipe at the No. 1 reactor at KEPCO's nuclear power plant in Oi, Fukui Prefecture, had worn down to a thickness below the government-set standard had compelled the company to check all its reactors and made it realize that the pipe in the Mihama plant had been left unchecked. This means that the company failed to follow maintenance regulations over the years and, as a result, the wear continued to reduce the pipe's thickness from 10 mm to 0.4 mm in some places.

In the case of TEPCO's irregularities, the most serious was the hiding of the fact that a pump in the emergency core cooling system at the No. 1 reactor of its Kariwa nuclear power plant in Niigata Prefecture was out of order in May 1992. Power companies should realize that a lax attitude toward safety will deepen public distrust of nuclear power plant operations.