Tritium in Fukushima waters below detectable level month after dump

Tokyo, Sep 25 (EFE).- The levels of tritium in seawater around the Fukushima nuclear power plant remain below the minimum detectable level a month after the start of the plant dump, the Japanese government reported Monday.

Personnel from the Japanese Environment Ministry were carrying out radioactivity tests on water samples taken at different points around the plant since the dump began on Aug. 24 and so far no abnormal levels have been detected.

In the latest data published Monday, about a month after the start of the discharges, the concentration of tritium was below the detectable minimum of 10 becquerels per liter, specifically between seven and eight units.

The so-called detection limit of an analytical method is the minimum level that the substance studied must have to be detected with reasonable certainty. When lower levels are identified (in this case 10 Bq/L), it is considered that it could be a false positive and therefore this measurement is taken as a reference.

The samples of this study, the fifth of its kind, were collected Tuesday at 11 points off the coast of Fukushima prefecture, in the northeast of the country, including a point near the area where the river ends and another 50 kilometers away.

In all measurements carried out to date, tritium levels have remained below the minimum detection level, according to figures provided by the Japanese authorities.

The Japanese government plans to continue monitoring tritium levels once a week for the time being.

Neither the owner of the plant and responsible for the spill, the company TEPCO, nor the International Atomic Energy Agency have detected unusual levels in their measurements.

Millions of tons of contaminated water have been generated in the plant facilities, either by the cooling work of the damaged reactors and the fuel melted in the 2011 atomic accident, or by the rainwater leaks over the years.

This water is treated through a complex filtering system that eliminates most of the harmful radioactive elements, except tritium (a nuclear isotope present in nature), before being stored in tanks to be discharged. This treated water is what was dumped.

There are currently more than 1,000 tanks on the plant grounds and their discharge is expected to last at least 30 years.

The treated water is diluted to reduce the levels of tritium present to less than a quarter of the concentration allowed according to national safety standards and to levels within the international standards considered by the IAEA. EFE

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