On July 22, 2024, at the dredging work site of the Hirono Thermal Power Plant navigation channel maintenance project located at 58 Shimokitasako, Futaba-gun, Hirono Town, Fukushima Prefecture, a worker from Yugen Kaisha Sensui Sakamoto drowned during scuba diving operations at a seabed approximately 5 meters deep, receiving air from a cylinder. The company's executive director did not require the worker to wear buoyancy compensators or life jackets, nor did he carry a depth gauge or underwater watch during the operation. As a result, the company and its executive director were each fined 200,000 yen on April 25, 2025, for violations of the Labour Safety and Health Act.