The operator of the crippled Fukushima Daiichi nuclear power plant on Wednesday started a fourth release of treated radioactive water into the sea, in what will be the last discharge for the fiscal year ending March. As in the previous rounds, Tokyo Electric Power Company Holdings Inc. will discharge 7,800 tons of treated water over about 17 days, having confirmed that the radioactivity level of the latest batch of water meets the standards set by the government and the utility. China, which opposes the water release, has banned Japanese seafood imports since the first discharge in late August…