Výběr zpráv ze sítě NucNet - 16. týden 2011
Slight Fall In
Radioactive Water Level At Fukushima-Daiichi
Tokyo Electric Power Company (Tepco) says the level of
highly radioactive water at the Fukushima-Daiichi nuclear
power plant has fallen since work started on 19 April
2011 to remove it from the unit 2 reactor complex.
Tepco said the level of contaminated water in a tunnel
linked to unit 2 was one centimetre lower than the
previous day as of 07:00 local time (midnight central
European time) on 20 April 2011.
That amounts to a reduction of 210 tonnes of the water in
the tunnel, pumped out at a rate of 10 tonnes per hour,
Tepco is aiming to remove 25,000 tonnes of the
contaminated water from the unit 2 turbine building
basement and connecting tunnel to a nearby processing
The contaminated water needs to be moved because there is
a risk it might leak into cable trenches and pits outside
the unit’s controlled zone and from there flow into the
Contaminated water has also been found in the turbine
hall basements of units 1 and 3, although its level of
radioactivity is much lower than the water at unit 2.
The total amount of water to be removed is estimated at
more than 60,000 tonnes, the International Atomic Energy
Tepco will monitor the current pumping rate for 10 days
or more and then add more pumps, in an effort to move
10,000 tonnes of the highly radioactive water by mid-May.
With the cooling systems at units 1, 2 and 3 still out of
order, Tepco has been pumping fresh water into the
reactor pressure vessels and spraying the spent fuel
ponds at units 1, 2, 3 and 4 in an effort to stop nuclear
While this has so far prevented a dangerous over-heating
of the reactor cores and spent fuel ponds, it has also
created a large quantity of contaminated water that Tepco
needs to remove before other work can progress.