Bitumen Solidification Facility at Unit 2 of Japan's Ikata Nuclear Power Plant Returns to Normal

Shikoku Electric Power Co. reported on August 25, 2026, that the bitumen solidification facility at Unit 2 of Japan's Ikata Nuclear Power Plant, currently in a decommissioned state, had returned to normal operation at 10:45 a.m. that day. The gasket at the joint of the mixer top cover, where the earlier abnormality had been detected, had been replaced, and trial operation results showed no abnormalities.

The incident occurred on April 28. On that day, when operators started the bitumen solidification facility in the controlled area of the reactor auxiliary building, they observed a steam-like phenomenon near the mixer thermometer, which subsequently disappeared on its own. Maintenance personnel later inspected and confirmed at 3:05 p.m. that the steam-like gas originated from inside the mixer and had escaped through the joint of the mixer top cover; at 5:06 p.m., the bitumen solidification facility was shut down.

Visual inspection revealed deformation in the gasket at the joint of the mixer top cover. After the replacement gasket arrived, maintenance personnel conducted a disassembly inspection of the equipment, confirmed no abnormalities in the mixer body itself, and replaced the relevant gasket with a new one.

After the replacement was completed, Shikoku Electric Power conducted a trial run of the bitumen solidification facility, confirming that no steam-like escape phenomenon recurred at the joint of the mixer top cover and that the equipment was operating without any issues. Shikoku Electric Power stated that this incident had no impact on the unit and caused no radioactive impact on the environment, and that further detailed investigations would continue.