#Fukushima I Nuke Plant: 700 Liters of Highly Contaminated Water Leaked

Diposkan oleh Pengetahuan dan Pengalaman on Friday, August 5, 2011

The water leaked (for nth time) somewhere in the contaminated water treatment system at Fukushima I Nuke Plant. This time, what's notable is not that the system leaked but the density of radioactive materials in that leaked water. I'm surprised TEPCO actually announced the numbers:
  • Cesium-134: 5.5 million becquerels/cubic centimeter

  • Cesium-137: 6.27 million becquerels/cubic centimeter

They are much, much higher than the numbers below that TEPCO last announced (July 15) as the densities of radioactive materials in the water before the treatment:

  • Cesium-134: 1,500,000 becquerels/cubic centimeter (1.5 x 10^6)

  • Cesium-137: 1,700,000 becquerels/cubic centimeter (1.7 x 10^6)

So, in the 700 liters of water that leaked, there are:
  • Cesium-134: 5.5 million x 1000 x 700 = 3,850,000,000,000 or 3.85 terabecquerels

  • Cesium-137: 6.27 million x 1000 x 700 = 4,389,000,000,000 or 4.389 terabequerels

From Yomiuri Shinbun (1:04AM JST 8/6/2011):

東京電力は5日、福島第一原子力発電所の集中廃棄物処理施設の建屋内で、高濃度の汚染水約700リットルがホースから漏れているのが見つかったと発表した。

TEPCO announced on August 5 that 700 liters of highly contaminated water was found leaking from the hose inside the Central Waste Processing Facility at Fukushima I Nuclear power Plant.

 建屋外への影響はないが、水漏れが見つかるまで東電はこの汚染水の濃度を把握していなかった。安全管理のずさんさが改めて浮き彫りになった。

There was no effect on the environment outside the building. TEPCO hadn't tested the density of the contaminated water [at that location?] until the leak was found. It again raises the question of the effectiveness of TEPCO's safety measures.

 東電によると、漏れが見つかったのは、汚染水処理システムで使われる吸着剤入り容器を洗浄した後、水を処理システムに戻すホース。この汚染水に含まれる放射性セシウム134の濃度は1立方センチ・メートルあたり550万ベクレル、セシウム137が627万ベクレルで、3、4号機タービン建屋の地下にたまった高濃度汚染水とほぼ同等だった。

According to TEPCO, the leak was found at the hose that routes the water used to flush the vessels [Kurion's system] back into the treatment system. Cesium-134 was detected at 5,500,000 becquerels/cubic centimeter, and cesium-137 was found at 6,270,000 becquerels/cubic centimeter. The level of cesium is about the same as that of the contaminated water in the basements of the turbine buildings at Reactors 3 and 4.

What? That's the level of contamination in the water in Reactors 3 and 4? That's news to me also. Water in the basements of Reactors 1 and 2 is considered even more radioactive.