Sunday 12 May 2013

Update 11 May 2013

Hi folks
Time for my monthly update. You'd think things would be settling down at Fukushima Daiichi - after all, the end of the accident was proclaimed back in December 2011 - but there's just one problem after another. It doesn't affect us here in the middle of the prefecture but it all adds to the uncertainty for those who've been evacuated. More of them later. First, let's take a look at progress at the site.

Dealing with the ever-growing volume of contaminated water from the reactor buildings continues to be the main priority. It's increasing at a rate of 400 tonnes a day. The fuel in reactors 1 to 3 still requires cooling but that water is in a self contained recycled system although some water does leak out of cracks in the reactors. The main problem is groundwater pouring into the base of the buildings. This is pumped out and stored in cylindrical tanks covering large areas of the site. One solution was to construct large storage pools but last month there was a serious leakage so they're currently being emptied. The latest is that Tepco has sunk 12 wells at the top of the cliff behind the row of reactors to pump up some of the groundwater and divert it via a separate channel into the sea. This water has been tested and found to contain only 1 becquerel/litre of radioactive material so the local fishing industry is likely to agree. After all, this will reduce the overall volume of contaminated water from 400 to 300 tonnes/day.

On the other hand, the fishing industry have said they won't agree to water that's been through Tepco's other trump card, the ALPS cleaning plant, being dumped in the sea. This system removes 62 kinds of radioactive material but no amount of filtration, desalination or distillation will rid the water of the isotope tritium. So this water will have to be stored in more tanks.

There's also talk of building a wall underground on the inland side of the reactors to contain the groundwater. But this could have the adverse effect of altering the flow: if levels inside the building were higher, contaminated water would start to leak out into the soil and eventually into the sea. All very tricky.

There's been progress on the reorganisation of the evacuated areas. Futaba County was holding out for the whole county to be put in the 'difficult to return' zone ( the mayor resigned over the issue) but in the end they towed the line and went along with the government's plan to divide the county according to radiation levels. So by the end of this month all 11 counties that were in the original exclusion zone will have been 'reorganised'. 76,000 people are affected.

You'll recall that the exclusion zone, evacuated immediately after the disaster, was a crude semi-circle 20 km around Fukushima Daiichi. But the plume travelled north west and the new zones reflect actual levels of airborne radiation. The new 'difficult to return zone' (levels of over 50 mSv/yr) spreads in a band 30 kms in a north westerly direction. The area is barricaded. 25,000 people used to live there. Next there are areas of 20 - 50 mSv/yr, some to the south of the 'difficult to return' area but mostly in the north in Iitate County. These areas are 'restricted residence'. The 19,000 people affected can travel in and out freely but not stay overnight. Then there are the so-called 'areas being prepared for having the evacuation order lifted', where radiation is under 20 mSv/yr. 32,000 people used to live there. Businesses are allowed to function in this area and people can go to work - but the evacuation order is still in place, they can't stay overnight.

The terminology used to describe the new zones is clumsy (glossary below). As one man said, 'It's gone from four syllables (keikai kuiki) to six syllables (kinan konnan kuiki) but nothing's changed'. For those who used to live in the worst affected areas of Namie, Futaba, Okuma and Tomioka that may be true. The area is barricaded, they can't go back and don't know when they'll be able to return. There are still questions about the location of the interim waste storage facilities (though surveying has started), but no talk of buying land and property, and nothing definite yet about establishing 'new communities' elsewhere.

For those in the other areas, there is progress. Decontamination is well underway and most of the infrastructure is back to normal. People can go back and start to tidy up - although they're not allowed to stay the night. But in spite of the reorganisation, 150,000 people have evacuated (either because they're in these three zones or voluntarily) and they still have no idea when they'll be able to return home. And with the series of troubles at the nuclear plant, the power outages and problems with water, the accident is far from over.

On a brighter note, I saw on TV that Tachibana Primary School, which is in one of the areas in Koriyama with the highest levels of radiation, had its sports day outside for the first time since the disaster. Little by little there is progress.
All the best

警戒区域   (keikai kuiki )  The original 20 km exclusion zone.
帰還困難区域   (kikan konnan kuiki)  The 'Difficult to Return' zone, 326 with airborne radiation over 50 mSv/yr
居住制限区域   (kyoju seigen kuiki)   The 'Restricted Residence' zone, 143 with airborne radiation 20 -  50 mSv/yr
避難指示解除準備区域   (hinan shiji kaijo junbi kuiki)   The 'Preparatory Lifting of the Evacuation Order ' zone, 418 with airborne radiation under 20 mSv/yr

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