"I Knew That" Was the Reaction From a Yokohama City Assemblyman to Strontium Discovery in Yokohama

Concerned residents of Yokohama City tweeted their City Assemblymen about the discovery of radioactive strontium in Yokohama, the news broken by independent journalist Yasumi Iwakami. (Read my posts here and here for more.)

One assemblyman, Yutaro Yokoyama, gave an interesting answer to the strontium question. He said on his tweets:

(1st tweet)

『9月初旬から事実として扱っています。私たちの会派にとってSrは過去の事です。9/13常任委員会でも私自身が触れています。Srは水溶性が高いという特性がありますので。但し、降り注いだのか、ボランティア等（人・車）が媒体になったのかは不明。』

I knew that [discovery of radioactive strontium in Yokohama] since early September. For our political faction, strontium is a thing of the past. I myself touched on the [subject, I hope, not strontium] on the standing committee on September 13, as strontium is highly water-soluble. However, it's not known whether it fell from the sky or was carried by a volunteer (in person or by car).

(2nd)

『放射性物質、、福島に行けばどこでも手にいる物です。人為的に持ち込む事も可能です。人為的に持ち込まれたとしたら、市会議員はそれを追及する事は仕事ではないと思っていますので、私はしません。』

Radioactive materials can be easily obtained anywhere in Fukushima. It is possible to carry them by artificial means [as opposed to naturally falling from the sky, I guess]. If radioactive strontium came by artificial means, I don't think it is a job of a City Assemblyman to pursue how it got here, so I won't.

He is insinuating that water-soluble radioactive strontium was carried intentionally by a volunteer or by a car driven by a volunteer and released on top of an apartment building, as any radioactive material is readily available anywhere in Fukushima Prefecture. And it's none of his business as a City Assemblyman to figure out how it got there.

Best of luck, citizens of Yokohama.

In the meantime, one major MSM newspaper carried the story, and more to follow I hear.

Here's from Asahi Shinbun (3:32AM JST 10/12/2011):

横浜市港北区のマンション屋上の堆積（たいせき）物から、１９５ベクレル（１キロあたり）のストロンチウムを、民間の分析機関が検出した。東京電力福島第一原発事故で放出されたとみられ、結果の報告を受けた横浜市は、再検査を始めた。

195 becquerels/kg of radioactive strontium has been detected from the sediment on the rooftop of an apartment building in Kohoku-ku in Yokohama City. A private laboratory did the testing. It is considered to have been released from Fukushima I Nuclear Power Plant after the accident. On receiving the result, Yokohama City has doing its own testing.

　検出されたのはストロンチウム９０（半減期約３０年）。文部科学省の調査では福島県内や宮城県南部など福島第一原発から１００キロ圏内で検出されているが、約２５０キロ離れた横浜市内では初めて。

It was strontium-90 (half life of about 30 years) that was detected. The nuclide has been detected within 100 kilometers from Fukushima I Nuke Plant in Fukushima Prefecture and the southern Miyagi Prefecture according to the survey by the Ministry of Education and Science. However, this is the first detection in Yokohama City, about 250 kilometers from the plant.

　場所は築７年の５階建てマンション屋上。７月、溝にたまった堆積物を住民が採取し、横浜市鶴見区の分析機関「同位体研究所」で測定した。放射性物質が蓄積しやすい条件とみられるため単純に比較できないが、４～５月に福島市内の土壌から検出された７７ベクレルと比べても高い値だ。

Strontium-90 was detected on the rooftop of a 5-story apartment building which was built 7 years ago. A resident of the apartment building took the sediment in the drain and had it tested at Isotope Research Institute in Tsurumi-ku in Yokohama City. The result may not be easily comparable to the results in Fukushima, as radioactive materials may be concentrated in locations like this one. Nonetheless, it is higher than 77 becquerels/kg of radioactive strontium detected in Fukushima City in April and May.

　同じ堆積物からは６万３４３４ベクレル（１キロあたり）のセシウムも検出。私有地であることを理由に公表していないが、市衛生研究所でのセシウムの再検査でも、同じ堆積物から１０万５６００ベクレルが検出された。

From the same sediment, 63,434 becquerels/kg of radioactive cesium has been detected. The city hasn't publicly released the data as the building is a private property, but when the city did its own testing of the same sediment at Yokohama City Institute of Health, 105,600 becquerels/kg of radioactive cesium was detected.

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