How safe is this bypass system?

February 4, 2014

Gov't seeks approval for dumping Fukushima plant groundwater into sea

http://mainichi.jp/english/english/newsselect/news/20140204p2g00m0dm032000c.html 

TOKYO (Kyodo) -- The government on Monday sought approval of a nationwide fisheries federation to dump groundwater at the crippled Fukushima Daiichi nuclear complex into the sea on condition that the water's contamination level is far below the legal limit.

During talks with the head of the National Federation of Fisheries Co-operative Associations, industry ministry officials explained that they plan to set "strict" operational procedures for the pump system to allay the concerns of fishermen who think the move could deal a blow to their business.

Groundwater will be pumped out before it gets mixed with highly radioactive water accumulating at the basement of reactor buildings, and will be directed to the adjacent Pacific Ocean.

The measure is intended to prevent toxic water from continuing to accumulate at the nuclear plant site, but plant operator Tokyo Electric Power Co. has not been able to operate the system in the face of local resistance even after it finished installing a dozen pumping wells last March.

Currently, radioactive water, which is increasing by about 400 tons daily, is stored at hundreds of tanks TEPCO has set up at the plant's premises.

During the talks with the federation, the Economy, Trade and Industry Ministry officials proposed a more stringent maximum contamination level for judging the safety of water for release, compared with the legal limit.

The government and TEPCO believe the legal limit will be satisfied if the groundwater contains less than 10 becquerels per liter of beta ray-emitting radioactive material such as strontium-90, and 30,000 becquerels per liter of tritium, among other radioactive substances.

But they decided to set a goal to operate the system on the condition that the water contains less than 5 becquerels per liter of beta ray-emitting radioactive material, and 1,500 becquerels per liter of tritium.

The officials also said the radiation level of groundwater will be checked each time before releasing it into the sea and that the operator will stop pumping out groundwater if its contamination level exceeds the limit.

Hiroshi Kishi, the head of the federation, told reporters after the meeting that he understands the importance of the so-called groundwater bypass system and his organization will make a decision on giving a green light to the operation after fully assessing the environmental monitoring system and other measures to prevent the spread of harmful rumors.