South Korea's oldest nuclear reactor is safe to operate, as a detailed inspection showed no problems with the unit that went into emergency shutdown last month due to an electrical glitch, the government said Friday.

   The Ministry of Education, Science and Technology announced after a meeting of the Nuclear Safety Commission said it has approved the restart of the 33-year-old reactor northeast of the southeastern port city of Busan.

   The 587-megawatt Gori-1 reactor has been kept offline since April 12 so engineers can determine the exact cause of the stoppage. The shutdown has fueled public concerns about the safety of local atomic power units following the massive quake and tsunami which crippled Japan's Fukushima nuclear power station in mid-March.

   "The Korea Hydro & Nuclear Power Co. that operates all atomic power plants in the country has been informed of the commission's decision with the reactor expected to start power generation in the near future," Education and Science Minister Lee Ju-ho said.

   In addition, all of the country's 21 reactors have been found to be safe from natural disasters such as earthquakes and tsunamis, the minister said, adding the reactors responsible for 30 percent of the country's electrical power supply are being run in accordance with stringent guidelines and equipped to cope with serious electrical power failures.

   Despite no detection of problems, the country will spend 1 trillion won (US$922 million) in the next five years to significantly update safety features of its commercial nuclear reactors, Lee said.

   "The money will be spent to make local reactors safe from the kind of damage that hit the Fukushima plant," he said. "Upgrades will be carried out on 50 safety features and facilities."

   Related to the upgrades, the state-run Korea Institute of Nuclear Safety (KINS) said that all local atomic power units will be made to withstand flooding by tsunamis that destroyed power infrastructure in Japan, with mobile power generators to be acquired so they can be sent to power plants if all backups fail.

   The agency added that so-called passive autocatalytic recombiners (PAR) are to be built into all reactors vulnerable to hydrogen explosions. The PARs, which do not need electricity, can prevent hydrogen buildup inside a reactor containment area that could lead to explosions and release of radioactive materials.

   The KINS said that Seoul plans to increase the number of radioactive detection centers in the country from the current 71 to 120 in the coming years, while raising the existing seawall at the Gori nuclear reactor from 1.7 peters and present to 4.2 meters.

This will effectively make the plant safe from tsunamis reaching 10 meters.

   The agency, meanwhile, said that the country's old reactors like the Gori-1 will be subject to more stringent regular inspections in the future even if Seoul had already approved extensions of their service.

(Yonhap News)