China’s Xinhua news agency reported today:
Radiation readings that are 100-1,000 times the normal level have been found on the Pacific seabed near the crippled Fukushima No. 1 nuclear power plant, local media reported Tuesday.
The high levels of radioactive materials were detected from samples taken Friday from the seabed at points 20-30 meters deep, Kyodo News reported, citing the plant’s operator Tokyo Electric Power Co.
The Japanese government and the utility have been battling to keep the plant crippled by the devastating earthquake and tsunami in March under control. It is still leaking radioactive substances into environment.
This raises a number of issues. Seabed radiation is probably particles that have precipitated, rather that those carried by water, such as tritium. Also, this far after the most contaminated leaks and intentional releases, the more likely assumption is that these are longer-lived elements.