Stronger inspections planned on Gori nuclear power plant

Two signboards are set up in front of a circuit breaker on the second floor of a turbine room of the No. 1 reactor at the Gori Nuclear Power Plant in Gijang County, South Gyeongsang Province.

One signboard reads “The overview of the breakdown of the 4,160 V circuit breaker for the Gori No. 1 reactor,” and has a table showing the producer of the device, the length of the operation, and the cause of its breakdown. Loose contact of the connection part of its power supply was cited as the cause of the breakdown.

The operation of the nuclear reactor has been suspended until Thursday due to a circuit breaker malfunction on April 12.

Employees of the Korea Hydro and Nuclear Power Corp. look at the signboard whenever they pass the place. One employee said, “It was a dishonorable incident that happened due to a gap of several millimeters in the circuit breaker.”

A Dong-A Ilbo reporter visited the nuclear plant the day after the nuclear safety committee of the Education, Science and Technology Ministry finished an inspection of the facility.

Chung Yeong-ik, head of the Gori Nuclear Power Headquarters under the corporation, said, “All employees were shocked that the malfunction of just one of the five million parts in the nuclear facility will stop all operations,” adding, “We will conduct more thorough inspections on each part.”

For precise inspections on power supply devices, the corporation will introduce non-destructive test equipment.

The equipment that detects defects in machinery by shooting x-rays has only been used for piping or welding. Chung said, “A unit of non-destructive test equipment costs more than 100 million won (92,000 U.S. dollars), but we need it to strengthen inspection work,” adding, “We will also shorten the inspection period for each part.”

If one steps out of the facility, he or she can see a wide extent of sea. This will be impossible, however, as high sea walls will be built around the reactor to prevent the facility from getting flooded due to a tsunami or typhoon.

Mun Byeong-wi, head of the No. 1 reactor, said, “The Gori nuclear power plant is more likely to be affected by a typhoon than an earthquake due to its geographical location,” adding, “The facility has protective walls only for nuclear reactors but we are considering expanding the walls throughout the entire facility.”

A small amount of seawater entered the nuclear power plant when Typhoon Maemi hit the nation in 2003.

jermes@donga.com