Sunday, June 16, 2013

#Fukushima I Nuke Plant: Highly Radioactive Water Leak (6,700 Bq/cm3 All Beta) from ALPS, Hot Run Halted

The leak is apparently from the weld. Either they can't weld, or they can't test the weld. Or both.

The water that leaked is after the treatment by SARRY, also a Toshiba system, to remove radioactive cesium.

If you recall, SARRY, Toshiba's cesium absorption system, had a leak in February 2012 from what was clearly a defective weld of a pipe connected to the cesium absorption tank.

From Asahi Shinbun (6/17/2013):

高濃度汚染水漏れか 福島原発、放射性物質除去装置停止

Highly contaminated water leak at Fukushima I Nuke Plant, multi-nuclide removal system (ALPS) stopped


TEPCO announced on June 16 that a leak was suspected from one of the tanks at "ALPS", multi-nuclide removal system in Fukushima I Nuclear Power Plant that TEPCO had started to test at the end of March. Highly contaminated water before the treatment by ALPS may have leaked. The surface radiation at the weld of the tank is high, at 0.2 millisievert/hour. TEPCO has stopped the test run to investigate the cause of the leak.


It is the first time to stop ALPS due to trouble, TEPCO says, although the system stopped in April because of human error.


According to TEPCO, the cylindrical tank of 6 meters high and 3 meters in diameter contained about 25 tonnes of contaminated water. At 11PM on June 15, a TEPCO employee who was inspecting the condensation on the tank found dried water spots in brown color on the saucer (receptacle) of the tank. The weld on the surface of the tank was found with higher radiation, and it is assumed that the contaminated water leaked from the weld.


ALPS is being introduced to remove 62 types of radionuclides including strontium from the highly contaminated water. If the leak is confirmed, the tank will have to be replaced, which will delay the completion of the test run scheduled to run till the end of July.


There are three lines, A, B and C, in ALPS. The A line, which has been on a test run since March 30, will be stopped because of this leak. The line B has been on a test run since June 13, and the line C hasn't been tested yet.

TEPCO says in their latest email notice to the media (6/17/2013) that they tested the water they collected in a bucket. Beta is high:


We placed a bucket under the tank to collect the drips. We tested the water (370 milliliters) collected over 16 hours since yesterday (June 16), and the results are as follows:

 ・セシウム134 :1.9×10^0[Bq/cm3]
 ・セシウム137 :3.9×10^0[Bq/cm3]

Cesium-134: 1.9×10^0[Bq/cm3] (or 1.9 Bq/cm3)
Cesium-137: 3.9×10^0[Bq/cm3] (or 3.9 Bq/cm3)
All beta: 6.7×10^3[Bq/cm3] (or 6,700 Bq/cm3)


Anonymous said...

All right, so after Cesium "removal" this water stiil has 1900+3900=5800 Bq/liter of Cesium and this is the water that, after "removal" of the beta nuclides by Alps, is still laced by its original amount of tritium (i.e. radioactive water).
I guess these figures give an idea of how hard it is to deal with nuclear contamination.


Anonymous said...

No fear! They will run another test in a couple of days, using this time a brand new bucket and they will find the water perfectly clean!!!
Then TEPCO's official position will be: "The high radioactivity was not in the water but in the bucket", isn'it?

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