South Korean authorities expressed their concern to Japan over possible contamination of the environment due to the release of radioactive water by Tokyo Electric Power Co. into the Pacific Ocean from the Fukushima 1 Nuclear Plant, Kyodo news agency reported on Tuesday.
"It's the proximity between the two countries that makes Japan's release of water a pressing issue for us," the agency said, quoting an official announcement by South Korea through its embassy in Tokyo.
Seoul is determining the extent of possible environmental damage, the report said.
Tokyo Electric Power Co. (TEPCO), the Fukushima Daiichi Plant operator, began releasing around 11,500 tons of low-level radioactive water into the ocean on Monday.
The company said it was considering using silt-barriers in the ocean to prevent the further spread of radiation.
The content of radioactive iodine-131 concentration in the water near the No. 2 reactor is 7.5 million times the maximum allowable level under law, Kyodo cited TEPCO as saying.
The company said it regretted the decision but in this situation it is the only way to solve the problem.
The death toll from the March 11 quake and tsunami has exceeded 12,340, while nearly 15,350 remain unaccounted for.