The dissemination of reliable, realistic information out of knowledgeable Japanese sources has improved tremendously since yesterday. Nearly all of what has been shared in the previous several days of our site entries (below this one) has been verified. In addition, many reputable science information sites on the web have begun carrying Fukushima information. Most of the best science info sites have been reluctant to publish previously because the scientific community is cautious, but also demands that evidence be correct and eminently verifiable before making statements. It seems there is now enough reliable information for these sites to publish with the high degree of confidence they require. I prefer Science Daily, which has been my science info source of choice for more than 10 years.
If this is the case, then why have I been providing updates since Friday? Several reasons. First, I was on the design team and initial operating staff of an American Boiling Water Reactor, supplied by General Electric, which was an improved version of Fukushima’s BWR. We also built the Mark 3 containment around the reactor, which was a major upgrade over the Mark 1 at Fukushima. Several of the consulting engineers on the design team had previously helped design and build Fukushima Unit No. 1, and we routinely heard “When I was building Fukushima…” from them. Plus, we were endlessly comparing and contrasting the differences between Fukushima and our plant in our meetings. That’s part of what an engineering design team does. Thus, I know more than most about the technology associated with the accident at Fukushima.
Second, after my design work was completed I worked as public spokesperson and education coordinator for the power plant from 1981 until 1987. I went through the news media scare-mongering from Three Mile Island and Chernobyl, up close and personal. I know the western news media’s modus operendi, if you will. This gives me a relatively sharp eye for differentiating the realistic from the fictional. I must admit, some of the information I have presented over the past few days were largely educated guesses, based on what my training and experiences have taught me. Was I lucky to get them all right? That judgment is up to you.
Lastly, during my nuclear career I also developed a knack for “translating” the technical terminology used by the nuclear community into everyday language. I “de-teched” a considerable number of press releases, and even did a little of it for multi-PhD nuclear professionals who were preparing to speak with the news media during the Chernobyl accident. Hopefully, that “knack” is still with me. I further made some 300 local public presentations through the company speaker’s bureau. I guess that makes me somewhat glib.
Now, events at Fukushima since yesterday’s update…
The decay heat production inside the three stricken, and now-known-to-be-fuel-damaged reactors at Fukushima, continues to drop exponentially. By the end of the day tomorrow, heat production rates at each reactor will be but about 2 megawatts. This does not rule out the possibility of further fuel and/or internal reactor fuel component meltage over the course of the next few weeks, but it does make it increasingly unlikely with every moment that passes. This gives the plant operators the time to take creative emergency measures to keep the core covered with water before more fuel damage occurs…much more time than the first day of the accident. Undaunted, the news media continues to preach the “catastrophic meltdown” gospel. It’s their nature to do that. <sigh>
Yesterday’s question as to whether or not the Unit No. 4 fire was “in” the spent fuel pool has been answered. As this writer logically suspected, it was near the pool itself, on the refueling deck above the reactor. Not “in” the pool, which made no sense at all. The fire started at 4pm (Japan time) and was put out by 5 pm. As with any fire that lasts an hour, smoke continued to rise for about an hour after it was put out. The “smoke” being reported on March 15 was probably steam. Steam from where?
Because of the lack of electrical feeds coming into the plant, and the few undamaged emergency power systems having been nearly exhausted, the cooling system for the spent fuel pool had been lost. The exhausted fuel cells, including those recently removed from the Unit 4 reactor, produce small amounts of decay heat and the pool has subsequently heated up to 84 degrees centigrade (~183 degrees Fahrenheit). As most of us have seen in a very hot sauna or hot tub, a considerable amount of steam rises and the water is not actually boiling. This appears to be the case with the spent fuel pool on Unit No. 4. The pool’s surface is half as big as an Olympic-sized pool, thus the surface area is considerable. So the steam caused by relatively rapid evaporation is necessarily considerable. However, it is unlikely that the pool itself was ever actually boiling. Could it possibly boil…eventually? That’s hard to say, but my guess is it’s unlikely. Several week-old spent fuel produces decay heat, but not very much. (decay heat explanation on March 15 entry, below) At 8:30 pm this morning (March 16 – Japan time), the above scenario was officially confirmed. The pool is not boiling, but evaporation is considerable and the water level above the exhausted fuel cells is slowly dropping.
Now, a fifth reactor at the power plant complex is losing water level. The operators are using the (what seems to be) undamaged emergency diesel generator from Unit No. 6 to make enough electricity so that both Units No. 5 and 6 can run the pumps necessary to keep their cores covered with water. The operators at Fukushima seem to be doing as good a job as the situation allows. They should be commended.
Also this morning (March 16), it has been reported that the fire in the refueling deck area of Unit No. 4 has re-ignited. It took nearly three hours to put this one out largely due to a reduced workforce at the power plant complex. The reactor was not on fire, which was broadcast by a few news media outlets.
Also, the previous press reports of the containment structural damage at Unit No. 3 releasing raw radioactive steam into the outside environment, were incorrect. As we now know has been the case with Unit No. 4, the steam being seen is coming from the evaporation of the Unit No. 3 spent fuel pool. Not the reactor containment itself. It seems the containment is still doing its job quite well. Hey, three foot thick, steel reinforced concrete is pretty darn difficult to blow open.
And, finally, the latest report is that workers are preparing to pump sea water into the spent fuel pools of Units 3 and 4, to replenish the level lost to evaporation. The spent fuel cells in storage have not been uncovered.
Which brings me to our first explanation of the day. The boric acid being dropped on the open areas of the spent fuel storage pools at Fukushima is not to keep the spent fuel from going critical and experiencing a chain reaction. For a chain reaction to occur in uranium with very low concentrations of the fissionable isotopes U-235 and Pu-239 (1% or less), there must be water covering the fuel cells. Without the water molecules to slow down the neutrons, there cannot be any level of fissioning sufficient to bring the fuel to criticality. Its simply impossible! If the spent fuel cells were completely uncovered, there would be zero risk of the cells going into a critical chain reaction. The boric acid is a commonly used chemical for extinguishing fire. There is no chance of of the spent fuel going critical over the next few days, no matter what.
On another note, please allow me to wax nostalgic for a moment. One of the most important things learned by the American nuclear community (there is really no “nuclear industry”, per se) during Three Mile Island, was that it is imperative to keep the news media informed on a continual basis, until the crisis has passed. Also, any communications to the press must be given in everyday language, as much as possible. If everyday language is not possible, then be prepared to teach the press on what cannot be “de-teched”. All American nuclear power plants have a dedicated staff trained to do this, part and parcel to the type of emergency plans mandated by the Nuclear Regulatory Commission (NRC). During emergencies, regular communication with the news media is mandatory.
Unfortunately, there is no such mandate in Japan. The Japanese government and the nuclear community in Japan are taking a severe public relations bashing for poor communication, and they deserve it. It has taken the better part of five days for sufficient reliable information to become available so that the scientific community of the world can begin to get involved and reliably informed. Those scientists who have offered their opinions up until now are either spokespersons for a press-thirsting group or organization, or science media stars (like Bill Nye). It should never have taken this long to get reliable, reputable information to the world’s science community. Hopefully, Japan and the rest of the nuclear community around the world will learn what we in America learned more than thirty years ago…be prepared to deal with the news media. Be very prepared! You have everything to gain and nothing to lose by doing this, but have nothing to gain and (perhaps) everything to lose by not doing this. Case in point…Japan!
