240,000 Bq/Kg at 5km from Imperial Palace

240,000 Bq/Kg at 5km from Imperial Palace3


The extremely radioactive black substance was found at 4km from the center of Tokyo.

In 10 minutes walk from Hirai station of JR Sobu line, where is about 4 km from Tokyo station, 5 km from Imperial Palace

black substance was found in several places near the play ground of a public estates.



A local citizen’s group found this and had it analyzed by Prof. Yamauchi from Kobe university. He measured 243,000 Bq/Kg of cesium and the surface dose was 2μSv/h.

Mr. Ishikawa, the chairman of citizen’s group states, the black substance is now everywhere in Tokyo, and it moves by wind or rain.

Roughly estimating, the soil around the black substance is contaminated as 15,600,000 Bq/m2 (cesium134/137).

In Belarus, the place where is more contaminated than 1,480,000Bq/Kg (cesium137) was defined as mandatory evacuation area.

To double the Belarus standard to make it close to the total of cesium 134 and 137, it becomes 2,960,000Bq/m2.

The graph to compare Tokyo to the mandatory evacuation area in Tokyo is below, which shows the contamination situation around Hirai Station is worse than no-man’s zone of Belarus by 527%.


240,000 Bq/Kg at 5km from Imperial Palace


240,000 Bq/Kg at 5km from Imperial Palace2



↓ The black substance and a baby stroller

240,000 Bq/Kg at 5km from Imperial Palace5


240,000 Bq/Kg at 5km from Imperial Palace6

240,000 Bq/Kg at 5km from Imperial Palace7


Source 1 2 3


Français :

240 000 Bq/kg à 5 km du Palais Impérial


240 000 Bq/kg à 5 km du Palais Impérial

De la substance noire extrêmement radioactive a été trouvée à 4 km du centre de Tokyo.
A 10 de marche de la gare de Hirai sur la ligne JR Sobu qui est à environ 4 km de la gare de Tokyo, 5 km du Palais Impérial
la substance noire a été trouvée en plusieurs endroits près de l’aire de jeu d’une résidence publique.


Un groupe d’habitant l’a trouvée et faite analyser par le Pr. Yamauchi de l’université de Kobe. Il a relevé 243 000 Bq/kg de césium et la dose en surface était à 2 μSv/h.
M. Ishikawa, le président de l’association affirme que la substance noire est partout dans Tokyo à présent et qu’elle se déplace selon le vent ou la pluie.
En estimation grossière, le sol autour de la substance noire est contaminé à 15 600 000 Bq/m² (césium134/137).
En Bielorussie, les endroits contaminés à plus de 1 480 000 Bq/kg (césium137) ont été définies comme zone d’évacuation obligatoire.
En doublant le standard biélorusse pour le rapprocher du total des césium 134 et 137, on en arrive à 2 960 000 Bq/m².
Le graphique comparatif entre Tokyo et la zone d’évacuation obligatoire est le suivant et il montre que la situation de la contamination autour de la gare de Hirai est pire que la zone interdite biélorusse à 527 %.

240 000 Bq/kg à 5 km du Palais Impérial 1
240 000 Bq/kg à 5 km du Palais Impérial 2

↓ La substance noire et une poussette

240 000 Bq/kg à 5 km du Palais Impérial 5

240 000 Bq/kg à 5 km du Palais Impérial 6

240 000 Bq/kg à 5 km du Palais Impérial 7

Sources : 1 2 3 4

About this site

This website updates the latest news about the Fukushima nuclear plant and also archives the past news from 2011. Because it's always updated and added live, articles, categories and the tags are not necessarily fitted in the latest format.
I am the writer of this website. About page remains in 2014. This is because my memory about 311 was clearer than now, 2023, and I think it can have a historical value. Now I'm living in Romania with 3 cats as an independent data scientist.
Actually, nothing has progressed in the plant since 2011. We still don't even know what is going on inside. They must keep cooling the crippled reactors by water, but additionally groundwater keeps flowing into the reactor buildings from the broken parts. This is why highly contaminated water is always produced more than it can circulate. Tepco is planning to officially discharge this water to the Pacific but Tritium is still remaining in it. They dilute this with seawater so that it is legally safe, but scientifically the same amount of radioactive tritium is contained. They say it is safe to discharge, but none of them have drunk it.


May 2012