The restart of the ALPS water treatment system and a new estimate of when areas directly around Fukushima Daiichi will be habitable again highlighted the news from Japan this week.
Recent developments related to the Tokyo Electric Power Co. nuclear plant severely damaged in 2011 include:
Upgraded ALPS Treatment System Restarts
One of the primary water treatment systems at the plant began operating at full capacity this week after upgrades to address a string of equipment problems. The last of three lines of the advanced liquid processing system restarted Sunday, TEPCO announced in a release, following the restart of the first two lines on May 23 and June 9. The system to remove a range of radionuclides from water exposed to damaged reactors and other contaminated areas first came online in October of 2012. But the hastily built system experienced frequent leaks, filter replacements and other issues. Recent upgrades include new filter gaskets more resistant to radiation exposure. At full capacity, ALPS can process 750 metric tons of water per day. TEPCO also plans to add two supplemental systems with similar decontamination capabilities.
Nearby Areas Expected to be Habitable in 7 Years
Estimates from Japan's Environment Ministry released this week indicate that cleanup efforts and natural forces will reduce potential radiation exposure in areas close to the plant from 100 millisieverts per year to below a 20 millisievert evacuation threshold by 2021. Without decontamination efforts, the government expects those levels would drop to 37 millisieverts per year in that time, and decontamination work could drop that to between 9 and 19 millisieverts, the Mainichi Daily News reported. In less-contaminated areas that undergo remediation, annual doses of about 50 millisieverts would fall to between 6 and 11 millisieverts in 2021, ten years after the accidents.
TEPCO recently released images of this water-borne robot it plans to use to inspect submerged areas near the torus chambers of damaged reactors. It will work in concert with a surface-based robot that can use Doppler radar to inspect pipes for cracks.