#Fukushima I Nuke Plant: Concrete Fill Failed on the Pit Near Ocean

Follow-up on my post from last night.

Murphy's law. You can pretty much bet the next attempt will go the same way.

Mainichi Shinbun has BOTH the diagrams of that part of the plant AND the photograph of the vertical shaft (they call it "pit", photo is from TEPCO) that TEPCO had found highly radioactive water gushing into the ocean and which it tried to pour concrete on April 2.

Points from Mainichi Shinbun (in Japanese, emphasis added; 9:27PM JST 4/2/2011):

• TEPCO announced on April 2 that it had found highly radioactive (1,000 milli-sievert) water at the bottom of the pit, a vertical shaft made of concrete, near the ocean, at around 9:30AM.

• The pit is 1.9 meter x 1.2 meter x 2 meter (length x width x depth), and 10 to 20 centimeter-deep water was found at the bottom.

• From 1.2 to 1.4 meters FROM THE SURFACE OF THE WATER, the radiation exceeded 1,000 milli-sievert/hr, and near the top of the pit close to the surface the radiation measured 400 milli-sievert/hr.

• The side of the pit that faces the ocean has a 20-centimeter crack [doesn't say 20 centimeter in width or the length], through which the contaminated water was flowing into the ocean.

• TEPCO said it just found out that the trench that is now filled with the radioactive water [that trench, during the normal operation, remains dry, and it houses pipes for the condenser unit to cool the turbine] and the trench that houses electrical cables were connected near the ocean [see the diagram].
  
  [The pink square in the lower right is the pit. The fat, grey lines indicates the pipe trench filled with contaminated water. The fat white line coming out of the pit is the trench for electrical cables. Notice the pipe trench connects to the cable trench near the pit.
  
  The mesh to the right of the pit depicts the water filter, behind which sits the pump room. The blue area at the bottom is the ocean.]
  

• Iodine-131 and other radioactive materials were detected in the same, high concentration from both the pit water and the water in the pipe trench.

• TEPCO had noticed the high radiation coming from this pit on April 1, but it was not until the morning of April 1 that they found water in the pit and tested it for radiation.

• As to the reason for this delay, TEPCO explained that it didn't occurred to them that the contaminated water from the trench may have gone into this pit, and that they weren't vigilant enough.
  

• On April 2 afternoon, TEPCO poured 5 cubic meters of concrete and filled the pit [1.9x1.2x2=4.56], but that didn't stop the contaminated water flow into the ocean. On April 3 morning, TEPCO will attempt to drill a hole at the junction of the two trenches [i.e. one that has been filled with contaminated water and the one that houses electrical cables which connects to this pit] and pour in the special resin that will expand on contact with water.

• Nuclear and Industrial Safety Agency (NISA)'s Nishiyama says "Water from this pit may be one of many sources for the contamination of the ocean," and has ordered TEPCO to check for other cracks around the Reactor No.2 as well as more samplings of seawater near the pit. Nishiyama also said "This may be one of [several] sources of sea water contamination."

Mr. Nishiyama is backtracking. Yesterday he was strongly indicating this pit was THE source of contamination. He is such a fine specimen of a Japanese career bureaucrat.

So, if TEPCO is to be believed (I know I know, but there are tons of people in Japan who want to believe TEPCO and do believe and defend TEPCO - more on that later), it didn't know that the electrical trench was connected to the pipe trench (filled with contaminated water) near the ocean. There could be several possibilities:

1. No one at TEPCO bothered to look at the Plant's blueprint; or
   

2. The blueprint doesn't exist; or
   

3. The blueprint does exist, but doesn't reflect the final layout of the entire plant, which must have been changed from the original plan as the construction progressed; or
   

4. TEPCO management didn't bother to ask the plant workers who may know about this pit and trenches and how they are connected - i.e. maintenance workers, electricians; or
   

5. TEPCO didn't ask whether Kajima, the general contractor who built the whole plant, had the final blueprint of the plant or know about how all the rest of the plant other than nuclear reactors and turbines was laid out. (In turn, Kajima would have to be smart enough to ask their retired engineers who actually dug the trenches...)
   

Instead of asking lowly workers who may actually know a thing or two about pipes and ducts and trenches, TEPCO and the government (most notably PM Kan) have been seeking advice from the nuclear experts - scholars, researchers - many of whom probably do not have a clue how a nuclear plant is physically laid out.

Don't hold your breath waiting for successful plugging of the trench junction with this special resin. Even if that succeeds, Nishiyama now admits the leak from this pit may be just one of many that they don't know yet.

By the way, NISA's Nishiyama is the one who threatens the Japanese with blackouts unless they continue to accept nuclear power (see my older post here).

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