The accident at the Fukushima Daiichi nuclear power plant in March 2011 has resulted in the release of many radioactive isotopes. This has added significantly to the level of radiation in the environment and studies show this to inversely correlate with the distance from the site. The concern over artificial radiation caused by isotopes including Caesium-137 that have a long half-life is heightened by its ability to easily move and spread in nature. This raises the question of to what extent are people living further away from the site at risk to radiation exposure. Therefore to address this we sought to monitor radiation levels in soil samples at sites not in the immediate vicinity of the accident. These include those close to major population areas along the Tama River flowing through Kanagawa prefecture near to the Tokyo Metropolis and into the Tokyo Bay. Here we report our methodology and results thus far obtained.

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