Regulators OK restart of Gori-1 reactor

Nuclear safety authorities have approved the restart of the Gori-1 reactor in 24 days time, saying that their close inspection found no problems with the nation’s oldest reactor whose operation was halted due to a breakdown in one of its circuit breakers.

They also called for emergency diesel generators and up-to-date hydrogen removal equipment to be installed at all of the nation’s 21 atomic power plants to help them withstand worst-case scenarios, such as those seen in Japan’s latest earthquake and tsunami.

“The atomic regulators checked those items reviewed back in 2007 to keep operating the Gori-1 and the recently raised question regarding its reactor vessel. They also analyzed the cause of the abrupt suspension of Gori-1 and the appropriateness of its follow-up measures,” Education, Science and Technology Minister Lee Ju-ho said in a press briefing Friday after a related committee meeting.

“The authorities confirmed that the safety level of major equipment and facilities at Gori-1 is suitable for continuous operation. The parts which caused the sudden halt of the reactor have been replaced. There would be no problems in restarting the Gori-1 reactor.”

The Gori-1 began operation in 1978 at the Gori Nuclear Power Plant in Gijang County, northeastern Busan. The government extended its life by 10 years after the completion of its 30-year life cycle in 2007.

Korea Hydro & Nuclear Power Co., operator of the Gori-1 reactor, will restart it soon after receiving official notification of approval. The company said it would take at least a day to raise Gori-1 power output to 10 to 15 percent of transmissible levels and three or four days to reach 100 percent.

Lee said that the government would take steps to strengthen the safety of all atomic power plants in Korea.

“The authorities have formulated 50 short- and long-term measures to keep all reactors up and running safely even if the worst disaster should happen,” he said.

“The government plans to spend about 1 trillion won over the next five years to implement the measures in stages.”

The steps call for heightening the coastal barrier around the Gori-1 reactor from 1.7 meters to 4.2 meters.

They also require the installation of waterproof doors and drainage pumps to emergency diesel generators to keep power supplies intact in the case of such emergencies as the inundation of an entire reactor site.

The government will also provide a mobile emergency generator to each reactor site in preparation for any accident crippling emergency generators, despite the watertight facilities. The mobile generator will be mounted on a car.

The authorities have braced themselves for one of the worst-case scenarios in which nuclear fuel should be damaged, spewing a large amount of hydrogen.

To prevent a hydrogen explosion, the government will install the latest hydrogen removal equipment, which does not need a power supply, at all reactors nationwide by 2013. All nuclear power plants will also be equipped with ventilation and pressure-lowering devices together with channels for emergency cooling water by 2014 to stop pressure inside containment vessels from rising.

Earlier, the ministry and the Korea Institute of Nuclear Safety inspected of the Gori-1 reactor after a circuit breaker broke it down on April 12, and concluded that there were no fundamental safety problems, but public concerns over the reactor safety did not subside. Korea Hydro & Nuclear Power asked the institute to conduct a close examination on April 20. The authorities checked the Gori-1 reactor from April 22 to May 3.

On April 18, the Science Ministry reported to President Lee Myung-bak that it would conduct a safety inspection of all 21 atomic power plants. An inspection team of mostly of civilian experts carried out safety checks from March 23 to April 30.

The inspection of all atomic power plants focused on checking Korean reactors in light of operational and technical problems revealed in the recent reactor accidents in Japan, as well as upgrading their manuals.

By Chun Sung-woo (swchun@heraldcorp.com)