The screened part in the drainage is designed with a 1/4 inch drop off, and runoffs are directed to it.
There is almost no human traffic [in this area], dusts and particles accumulated quite a bit.
The surface of rooftop made of resin-based material, and the radioisotopes adhered to it when the majority of the radioactive fallout drained into the area and accumulated.
A quick calculation gives fallout amount of 2,730.4 Bq/m2
(To understand the danger of this number, it falls between these two:
370 Bq/m2: Expand protective actions: stay indoors whenever possible, close windows, seal openings, cover gardens with tarps, shelter livestock, avoid ingestion of leafy vegetables and fruits harvested in fallout areas. Expand monitoring of food, water, and milk; discard or avoid ingesting foods and water contaminated by the indicator nuclides I-131 and Cs-137 above 370 Bq/kg or Bq/l (10,000 picocuries, the protection action level used by the US FDA to dispose of imported foods contaminated by Chernobyl-derived fallout). Continue monitoring of ambient radiation levels.
3,700 Bq/m2: Expand protective actions to restrict movement of children, outside workers, nonessential travel, and recreational activities such as hiking and sunbathing. Closely monitor food, milk, and water intake, sources, and radiation levels. Continue use of information technology to keep informed of ongoing emissions. Immediate sheltering is the best option to avoid exposure to a passing plume. source)
I think many rooftops of condos are structured similarly, and this story surely won’t be limited to ours.
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.