Record-high 5 million becquerels of strontium per liter

 February 7, 2014

TEPCO revises strontium data at Fukushima plant to record level

http://ajw.asahi.com/article/0311disaster/fukushima/AJ201402070096

THE ASAHI SHIMBUN

Tokyo Electric Power Co. corrected its radioactivity readings for groundwater from a well at the crippled Fukushima No. 1 nuclear plant to a record-high 5 million becquerels of strontium per liter.

TEPCO officials said the strontium levels were gauged again because the previous data was wrong. They also said radioactivity readings for water taken from other wells before September were also likely erroneous.

The company had said 900,000 becquerels of beta-ray sources, including strontium, were detected in water taken on July 5, 2013, from the observation well near a water intake for the No. 2 reactor turbine building.

The new strontium data indicates that the concentration of all beta-ray sources totals around 10 million becquerels per liter of water, according to the company.

TEPCO did not announce radioactivity levels of 140 samples of groundwater and seawater taken between June and November after it found strontium readings that were higher than measurements for all beta-ray sources.

The company attributed contradictory data to malfunctions of analytical equipment.

The utility also said Feb. 6 that 600 liters of contaminated water, containing 2,800 becquerels of beta-ray sources per liter, leaked from piping leading to a tank at the Fukushima nuclear plant.

Record-high strontium-90 in past Fukushima plant groundwater sample

http://mainichi.jp/english/english/newsselect/news/20140207p2g00m0dm038000c.html

FUKUSHIMA, Japan (Kyodo) -- The operator of the crippled Fukushima Daiichi nuclear power plant said Thursday that a groundwater sample taken from a well at the site in July last year contained a record-high 5 million becquerels per liter of radioactive strontium-90.

Tokyo Electric Power Co. initially said that it had detected 900,000 becquerels per liter of beta ray-emitting radioactive substances, such as strontium, in the water sample taken July 5, but found problems in the measuring equipment in October.

Estimating from the strontium-90 readings, a TEPCO official said that "all beta radiation could have been 10 million becquerels in total."

Strontium tends to accumulate in bones and is thought to cause bone cancer and leukemia.

The utility also said it will reanalyze past water samples, as some of the figures cannot be trusted.

The observation well, which is 16 meters deep, is situated between the Nos. 1 and 2 reactors at the plant.

It is also about 25 meters from the Pacific Ocean and around 6 meters from an underground tunnel from which highly radioactive water was found to be seeping into the sea shortly after the nuclear crisis began in March 2011.