Japanese officials plan to start discharging treated radioactive wastewater from the damaged Fukushima Daiichi nuclear power plant into the Pacific Ocean on Thursday, a contentious step more than 12 years after a massive earthquake and tsunami set off a battle against ever-increasing amounts of radioactive water at the plant.
The government and plant operator say the release is an unavoidable part of its decommissioning and will be safely carried out, but the plan faces opposition in and outside Japan. Here is a look at the controversy.
WHY IS THERE SO MUCH WASTEWATER?
The March 2011 earthquake and tsunami destroyed the plant’s cooling systems, causing three reactors to melt. Highly contaminated cooling water applied to the damaged reactors has leaked continuously to building basements and mixed with groundwater.
The plant operator, Tokyo Electric Power Company Holdings (TEPCO), has taken steps to limit the amount of groundwater and rainwater entering the reactor area, and has reduced the increase in contaminated water to about 100 tons a day, 1/5 of the initial amount. The water is collected and partly recycled as cooling water after treatment, with the rest stored in around 1,000 tanks, which are already filled to 98% of their 1.37 million-ton capacity.
WHY IS TEPCO RELEASING THE WATER NOW?
The government and TEPCO say they need to make room for the plant’s decommissioning and prevent accidental leaks from the tanks.
Japan has obtained support from the International Atomic Energy Agency to improve the transparency and credibility of the release and ensure it meets international safety standards. The government has also stepped up a campaign promoting the plan’s safety at home and through diplomatic channels.