Korean Nuclear Safety and Security Commission Approves 10-Year Life Extension for Kori Nuclear Power Plant Units 3 and 4

en.Wedoany.com Reported - On October 27, the Korean Nuclear Safety and Security Commission approved the continued operation of Kori Nuclear Power Plant Units 3 and 4 for an additional 10 years at its 2026-17th meeting. The two units are located in Gijang County, Busan, Republic of Korea, and are both 1,025 MW pressurized water reactors designed by Westinghouse, with a combined installed capacity of 2,050 MW. Under this license, Unit 3's operating period is extended to September 28, 2034, and Unit 4's to August 6, 2035. Korea Hydro & Nuclear Power (KHNP) plans to complete the restart of both units in the first half of 2027.

Kori Units 3 and 4 obtained operating licenses in 1984 and 1985, respectively, and entered commercial operation in September 1985 and April 1986. Both units had an original design life of 40 years and were shut down on September 28, 2024, and August 6, 2025, respectively. KHNP submitted the periodic safety review report for continued operation on September 26, 2022, and formally applied for a license amendment on November 16, 2023.

The Korea Institute of Nuclear Safety conducted a safety review from September 2022 to September 2026, lasting approximately four years, focusing on the aging status of structures, systems, and components, remaining service life, and equipment replacement and improvement plans. Although the two units share the same design, the regulator completed equipment condition and life assessments separately based on each unit's operating and maintenance records. The Korean Nuclear Safety Expert Committee conducted a preliminary review of the review results from March to September 2026, lasting approximately six months.

The radiological environmental impact assessment results show that the maximum radiation impact under continued operation conditions is 0.096 mSv, below the applicable standard of 0.25 mSv; the maximum assessed value under severe accident scenarios is 103.3 mSv, below the standard limit of 250 mSv. The regulator also reviewed the relevant accident management programs and approved the accident management plans for both units on October 15.

Under the implementation arrangements following approval, KHNP will carry out equipment replacement, facility modifications, and operational readiness inspections. The Korean Nuclear Safety and Security Commission will verify the relevant improvement measures and equipment conditions during on-site inspections, and the two units may resume operation only after confirming that safety requirements are met.