Just In: All Three Lines of ALPS Have Stopped at #Fukushima I Nuclear Power Plant

The entire ALPS multi-nuclide removal system is down again, as Line C has just been stopped as the water sample from Line C is found with high calcium content.

Line A was stopped three days ago, and Line B has been idle since March this year, when the water treated in Line B was found with high beta (in the order of 10 million Bq/L) and brand-new storage tanks got contaminated.

Stopping ALPS won't affect the cooling of reactors, as the treatment for the cooling water is done by SARRY (removal of radioactive cesium) and by the reverse osmosis apparatus (desalination).

From TEPCO's email alert for the press, 5/20/2014:

多核種除去設備（ＡＬＰＳ）Ｃ系については処理運転中でしたが、本日（５月20日）の定例のサンプリングにおいて、系統水に若干の白濁があること、カルシウム濃度が高いことを確認しました。

Line C of the multi-nuclide removal system ALPS has been in operation. However, we noted in today (May 20, 2014)'s scheduled sampling that the water [coming out of] Line C was clouded, and that it had high calcium content.

　このため、多核種除去設備（ＡＬＰＳ）Ｃ系について、同日午前９時00分、処理運転を停止し、循環待機運転に切り替えました。

Therefore, we stopped Line C at 9:00AM today, and switched it to the circulation stand-by operation. [I don't know exactly what TEPCO means; I'm guessing they are circulating the water within Line C instead of sending treated water into a storage tank.]

　この結果、多核種除去設備（ＡＬＰＳ）は３系統ありますが、全て処理運転を停止している状況となります。

As the result, all three lines of ALPS have stopped treatment operation.

　原因等については、今後調査いたします。

We will investigate the cause.

The cause, if it is the same as Line A which stopped three days ago after the water sample was found with high calcium content, is likely to be the defective cross flow filter, like this one on Line B (from TEPCO's Roadmap update page 24, 4/24/2014) (English labels are by me):

Whether the defective gasket is due to material defect, design defect or irradiation is unknown at this point.

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