- The waste water decontamination system at Fukushima Daiichi gets a lot of Japanese media attention because of irregular shutdowns due to piping leaks and moderately fluctuating flows through the system. What seems to be missing from all of this coverage is that the system has been continually decontaminating an average of over 800 tons of waste water per day since Saturday, and has averaged 700 tons per day since it was put into full-scale operation. Currently, the total amount of water being injected to the 3 RPVs is 400 tons per day. Thus, the “troubled” water decontamination system is treating double the RPV water injection rate every day. Yes, it will take a very long time to treat the more than 100,000 tons remaining to be decontaminated by this one system system, but the chance of restarting radioactive releases to the sea decreases with each day that passes. In addition, by adding Toshiba’s new system reported on last week, all waters could be decontaminated by the end of the year.
- The Japanese nuclear disaster task force, created in April, has announced the newly-revised plan for the second step towards bringing the Fukushima emergency to an end. The first stage’s completion was announced Monday, marking RPV temperature control and the virtual stoppage of continued air and water releases to the environment. The next stage has several target goals to be met by the end of the year. On the public side, the government will expand regular health checks on Fukushima residents, including frequent thyroid cancer screening tests on children, for as long as 30 years. Environmentally, a comprehensive radiation monitoring program will be directed toward finding what parts of the evacuation zones are safe for re-population. Plus, radioactive debris and sludge is to be stored and disposed of, but no detail on procedure or method is included. Technologically, they will clean up all the waste waters now accumulated at Fukushima Daiichi, cool the reactor bottom heads (where most of the corium has collected and solidified) to below 100oC (the cold shutdown target), and have all four spent fuel pool cooling systems in place and operating to keep the pools at a “normal” temperature (below 40 oC). Also implied by the task force is completion of encasing the explosion-damaged reactor buildings on units 1, 3 & 4.The task force’s “goals” for the end of the year should come as no surprise to anyone who has followed the events surrounding Fukushima. Two points in the announcement bear looking at, though. First, Monday the government announced the plan to re-populate the “safe” areas of the currently evacuated zones, but no prospective time-table was mentioned. Nuclear Disaster Minister Hosono says this could start as early as August, but the task force’s plan makes it sound like early next year. Who should the evacuees believe? Second, the below-100oC criteria for cold shutdown…TEPCO could do this now on RPVs #1 and 2! With the waste treatment system decontaminating twice the amount of water injected every day, and the decided possibility of a second, more efficient system being added in the near future, there will be more than enough decontaminated water to raise injection flow rates while continuing to reduce the contaminated water volume. Units 1 & 2 each use less than half the daily injections as is the case with unit #3. It’s about 100 tons a day, each. Doubling their flows would drop temperatures below the cold shutdown target inside of a week, and keep them there. Total injection flows for all three RPVs would still be at least 100 tons per day less than what the current waste water clean-up system is processing. Add Toshiba’s new system and the numbers get much better.
Another “target” for the plan is reducing public exposure to radioactive releases from the four damaged units. NHK reports the current radiation levels measured on the power complex property are 2 million times lower than they were at the height of the emergency on March 15, and below public exposure standards at the property boundaries right now. Further, NISA and TEPCO documentation on the current airborne radioactivity level on-site show them to be well below legal limits in Japan. In other words, this specific “target” has already been met! So, why include it as a target at all? Because the public perceives that “radiation leaks” from Fukushima are continuing, and political decisions are always driven by public opinion.
Finally, the problem with disposing of sewage sludge and contaminated tsunami debris. Government health standards for routine disposal methods are not trusted by local residents surrounding the disposal sites and processing plants. For example, even though the government arbitrarily lowered its sewage contamination limit for burial by a factor of seven, local residents living near the burial site at Yanaizu have blocked using it. Why? The town’s anti-dumping proclamation points out that government health standards cannot be trusted and, “We are concerned about possible health damage that could emerge several years later.” Plus, they say, there is no convincing proof that lower radiation exposure levels are safe. It’s clearly a case of NIMBY (Not In My Back Yard) based on phobic fear of radiation. Once again, the Hiroshima Syndrome rears it’s ugly head.
Meanwhile back in the USA…
- The Nuclear Regulatory Commission’s (NRC) Chairman Robert Jaczko has announced that an American nuclear “regulatory overhaul” will be completed in the next 90 days. Changes will be made to insure that “there is no repetition of what happened in Japan”. Included in the changes will be increased back-up power sources to further reduce the chances of a full power plant blackout. The changes will be based on recommendations made by the NRC’s Post-Fukushima task force, reported in this update last week. However the Nuclear Energy Institute points out, “The task force report does not cite significant data from the Fukushima accident to support many of its recommendations.” In other words, Jaczko and his task force are using Fukushima to effect changes that have nothing to do with “what happened in Japan”.Further, it seems these “changes” are little more than politically-expedient window dressing. The multiple back-up power sources already mandated for US nukes provide a high degree of confidence that the Fukushima emergency would not have happened here. For example, the emergency diesel generators at US nukes are enclosed in independent seismic structures that are water-tight, and have been for the better part of a decade, at least. If Japan had done the same with their diesels, it is likely the Fukushima accident would never have happened. If Jaczko wants to make the “better mousetrap” even better… fine! But, the NRC’s program announcement makes it seem like Fukushima’s accident could likely happen here unless the proposed changes are made. There is considerable high-confidence evidence that American nukes already avoid a “repetition of what happened in Japan”.