APR: your source for nuclear news and analysis since April 16, 2010

Saturday, July 9, 2011

Fukushima Daiichi: Almost at a milestone

It would appear that a number of the most important priorities of the recovery effort at the Fukushima Daiichi plant are about to be achieved. Quite a number of these were developed and promulgated in TEPCO's elaborate 'road map' for recovery. Some of the most important things to an informed, outside observer are the following:

-Stable cooling of the reactor cores (No. 1, No. 2, No. 3 plants)
-Prevention of further hydrogen explosions (all four plants)
-Stable cooling of the spent fuel pools (all four plants)
-Prevention of further spread of contamination in the ocean or ground water
-Prevention of further spread of airborne contamination

As to the first point, stable cooling of the reactor cores exists at this time. TEPCO has demonstrated its ability to fine tune the feed rate of cooling water to the reactors to control their temperatures. A great deal of work has gone into this effort, which has seen firefighting injection connection by fire trucks using seawater be replaced steadily at all three plants by fresh water injection using the normal feed system piping to the pressure vessels.

As to the second point, at this time TEPCO is preparing to commence nitrogen injection to the dry well of the last plant not already receiving nitrogen, namely No. 3 plant. Earlier attempts to reach the required location by use of a lift truck and robot proved daunting, so volunteer employees rode a lead-apron-draped scissors lift truck platform to the area and installed a fitting to allow nitrogen injection. As with the other plants TEPCO has received some specific instructions for reports from NISA which it is processing and will submit immediately. Once this is done and preparations made on site (which will not take long) nitrogen injection for the purpose of hydrogen gas inertion will begin at No. 3 plant completing the objective of the second point.

Third is the objective of achieving reliable cooling of the spent fuel pools. Operations in the last several days at No. 4 plant have seen the removal of rubble blocking a necessary system valve, operation of that valve, repair of some system piping and a preliminary filling test of the system. TEPCO is about to commence recirculating cooling of this spent fuel pool via heat exchangers located in the rad waste building. Item: It should be noted that the JAIF reports are indicating that TEPCO's analysis of spent fuel pool water show that MOST of the spent fuel at No. 2 and No. 4 plant spent fuel pools is UNDAMAGED.

The operations at the rad waste facility also point up item four, which is the prevention of spread of further contaminated water. TEPCO had accumulated over 120,000 tons of contaminated water on site from a number of sources, the worst of which was that derived from the feed and bleed cooling of the three damaged reactor plants. TEPCO has put immense and unprecedented effort into the establishment of a great deal of available storage space in the forms of on site buildings and tanks, tanks brought in by sea (the mega float) and many tanks brought in by land which have been joined with a complex decontamination / desalination plant built by a consortium of manufacturers (notably Kurion and AREVA.) The establishment of this network of cleanup system and tankage means that water on site is essentially now being recirculated, so that the previous constant worries of turbine building and pipe trench overflow so common over last two months are being alleviated.

Finally the fifth point mentioned above is the prevention of further aerial spread of contamination. TEPCO has practically been covering the entire site with anti-scattering agent which is quite visible on the various site buildings, and all over the grounds. More important perhaps is the fact that the reactor building enclosure work is now clearly producing tangible results, and the first building's enclosure is under construction at this time. Completion of these 'first round' enclosures at all four plants will prevent further spread of aerially dispersed contaminants, which is already very much lower than during the most serious phase of the accident.

It is no mistake to take the position that all of these things added together bring us to a fairly important place in the recovery effort where the worst challenges are now viewed as not only achievable but nearly achieved. For months now there have been so many constant but separate battles being fought on site and elsewhere to contain and control the massively complex accident site/scenario that at times it has seemed nearly impossible (and was advertised as completely impossible in the mainstream media.) It is clear now that all of this work has not only paid off but brought us to the brink of a turning point in the recovery at which we may say that the recovery effort is a success. Perhaps we will add all too hastily that this 'turning point' is, or will not be, a sharp curve but a broad swing slowly toward the final proper end direction in the recovery ... but the developments taken on the whole at this time are enough for this writer to finally say that we have reached a time where we may at least take a breath and a moment to reflect rather than take all our moments to scan the news wires and official sources for any further bad news, complications or hurdles.

There is very much work yet to be done, some of it dreadfully complicated and dangerous. This will be better detailed in the near future.

There are not sufficient words to express the true feelings for, and debt owed to, those men who have struggled heroically and tirelessly on site to bring us to this point. Many of them will continue at their work for many years, seeing the work though to complete decommissioning of the entire plant site.

Finally for now... We were hoping to have new large pictures of some of the work today, but TEPCO's press photos were uploaded very small in size and we will wait to see if proper hi-res photos are uploaded, or else if the press handouts have better illustrations before presenting them. If better photos are not issued we'll run with those available tomorrow afternoon.

9:40 PM Eastern Saturday July 9, 2011
ATOMIC POWER REVIEW

2 comments:

  1. Thank you Will for a well written summary. And in particular your heartfelt acknowledgment of the work and effort being done, and yet to be done, by the workers at the plant. I fully agree with your words.

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  2. Very good article! We don't hear SQUAT from the coyly anti-nuke mainstream media here of how well this "impossible" recovery is coming along! Unfortunately those nuclear workers and unsung heroes won't only be trivalized as victim pawns of the nuclear industry but as near guinea pigs for radioactive events. I wonder how Japan views them -- and how they would be viewed if they asked their countrymen to continue supporting nuclear power. We see the same industry support by coal miners here. It might take the supportive words of nuclear workers to counter the disasterous PR of their own companies. Too bad our companies don't seem to've stepped in to offer them air support.

    James Greenidge

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