Plant failures put Korean technology in doghouse

The recent halting of two nuclear reactors built using Korean technology has reignited a debate on whether the government should revise its design and safety regulations for nuclear power plants.

Nuclear power generators at Singori reactor No. 1 in Busan and Yeonggwang reactor No. 5 in South Jeolla stopped functioning on Tuesday.

This marks the seventh time that nuclear reactors in the country have shut down this year.

According to Korea Hydro & Nuclear Power Corporation, the turbines at Singori reactor No. 1 stopped at 8:10 a.m. after the rods controlling the frequency of nuclear fission malfunctioned.

The breakdown has again raised the issue of safety relating to nuclear power plants in the country, especially as the plants used standard Korean technologies and design.

The so-called Korean Standard Nuclear Power Plant format was first employed at Uljin reactor No. 3, which went into commercial operation in 1998. It was also used in the Yeonggwang reactor No. 5, while an improved and rebranded design known as Optimized Power Reactor-1000 was employed in the Singori reactor No. 1.

Tuesday marked the 17th malfunction at Yeonggwang reactor No. 5.

From the year 2000 until last month there have been 105 accidents or malfunctions at domestic nuclear power plants. Of these, 39 cases, or 37 percent, occurred at reactors designed using Korean technology, according to Jang Ha-na, a lawmaker with the Democratic United Party. Nine of the 23 reactors operating in the country now were built using Korean technology.

“Malfunctioning control-system rods may not pose a big risk so far, but this threat becomes greatly amplified if such problems combine with a natural disaster or a larger system breakdown,” said a senior executive with the Korean Federation for Environmental Movement.

By Lee Sun-min [summerlee@joongang.co.kr]