By Julie Makinen
17 February 2015
(Los Angeles Times) – Nearly four years after Japan’s massive March 2011 earthquake and tsunami, the country has made “significant progress” toward stabilizing and decommissioning the ravaged Fukushima Dai-ichi nuclear power plant, international nuclear inspectors said Tuesday.
However, the nearly 160 million gallons of contaminated water stored on-site pose massive logistical challenges, and examiners strongly urged Japan to consider controlled discharges of the liquid into the Pacific Ocean once it is treated.
The situation at the crippled plant remains “very complex” and “the benefits [of discharges] could be very, very huge” said Juan Carlos Lentijo, who led the team of 15 inspectors from the International Atomic Energy Agency on a nine-day mission that follows surveys in April and November 2013.
Japanese officials have been reluctant to take such a step at the plant 160 miles northeast of Tokyo, fearing it might further antagonize local fishermen and other residents affected by the initial accident and its aftermath. […]
About half of the water stored on-site has been treated to remove most radioactive contaminants, the IAEA team noted, though current technology does not allow for the easy removal of tritium, an isotope of hydrogen.
Unlike other contaminants, which are suspended or dissolved in water, tritium actually modifies the water molecules and therefore is difficult to separate out.
Still, tritium is considered one of the least hazardous radioactive materials produced by nuclear power plants, and Lentijo said “controlled discharges are a normal practice in the industry.”
“Most of the nuclear power plants are discharging treated water,” he said at a news conference in Tokyo. “This is accomplished with negligible impact on the environment and the safety of the people.” [more]