About 7,800 tons of treated radioactive water has been discharged into the sea from the wrecked Fukushima No. 1 nuclear power plant in the first round of disposal as planned, the plant operator said Monday.

Despite concerns voiced by local fishers and strong opposition from China, Tokyo Electric Power Company Holdings (Tepco) began the discharge of the water, which contained tritium levels below the prescribed limits. The release, which started on Aug. 24, is being monitored by the Japanese government and the International Atomic Energy Agency (IAEA).

As the volume of processed water, a result of cooling melted nuclear fuel, approached the plant's storage capacity limit, Tepco decided to release approximately 31,200 tons of this water in four rounds during the current fiscal year through March.