This week, international and Japanese authorities recommended releasing tritiated water at Fukushima Daiichi, while rising contamination levels in a well brought mixed news on efforts to control untreated water at the plant.
Recent developments related to the Tokyo Electric Power Co. reactors blacked out following Japan's 2011 earthquake and tsunami include:
IAEA: Discharge Treated Water
The preliminary report from 19 International Atomic Energy Agency experts visiting Fukushima Daiichi this week recommend that treated water at the plant be released into the ocean if it meets safety standards. The plant's treatment systems can reduce the levels of dozens of radionuclides to within drinking water standards, but few practical options exist for removing tritium. With an estimated 400 metric tons of groundwater seeping into plant buildings daily and on-site storage running low, the Asahi Shimbun reported that the IAEA and the head of Japan's Nuclear Regulation Authority support the controlled release of tritiated water. The IAEA team arrived on Nov. 25 to study Fukushima's decommissioning plans, seawater monitoring and the ongoing removal of spent fuel from unit 4. A preliminary report said Japan is achieving "good progress" in preparing for decommissioning, and a final report is due in January.
Contamination Increases in Well But Not in Harbor
Beta-emitting contaminants in a monitoring well near unit 2 were measured at 1.3 million becquerels per liter on Monday, Tokyo Electric Power Co. announced in a release. That is by far the highest reading of any test well at the site that day and represents a substantial increase since October, when levels were closer to 80,000 becquerels per liter. TEPCO cast the announcement as evidence that its remediation efforts are working, though, because there was no corresponding change in nearby seawater. TEPCO attributed this to groundwater pumping and barriers between the well and the plant's artificial harbor.