(Reuters) – High levels of a toxic substance called strontium-90 have been found in groundwater at the devastated Fukushima nuclear power plant in Japan, the utility that runs the facility said on Wednesday.
Strontium-90 is a by-product of the fission of uranium and plutonium in nuclear reactors as well as nuclear weapons, the U.S. Environmental Protection Agency says on its website.
The discovery of rising levels of such radioactive material is likely to complicate efforts by the utility, Tokyo Electric Power Co, to get approval to release into the Pacific Ocean what it calls water contaminated with low levels of radiation.
“This contaminated water should not be released to the ocean,” said Michiaki Furukawa, a nuclear chemist and professor emeritus at Nagoya University. “They have to keep it somewhere so that it can’t escape outside the plant.”
Testing of groundwater showed that strontium-90 increased from 8.6 becquerels to 1,000 becquerels per liter between December 8, 2012 and May 24, Fukuda said. That level is more than 30 times the legal limit of 30 becquerels per liter.
“Tepco needs to carry out more regular testing in specific areas and disclose everything they find,” added Furukawa, the nuclear chemist.
Testing also showed 500,000 becquerels per liter of tritium on May 24, compared with the legal limit of 60,000 and 29,000 on December 8, 2012. A becquerel is a measure of radioactive decay.
Tepco has struggled with the clean-up of Fukushima, the site of the world’s worst nuclear disaster in 25 years. It said in April it was running out of capacity to store the water contaminated in its still-makeshift cooling system.
Adding to its difficulties, about 400 metric tons (440.92 tons) of groundwater flow daily into the reactor buildings only to be mixed with highly contaminated water from cooling the melted fuel.
It has been trying to convince skeptical local fisherman that it is safe to dump 100 metric tons of the groundwater a day into the ocean to reduce the strain on its storage facilities.
Related articles on the Atomic Age:
- ２号機海側、地下水が高濃度汚染＝トリチウムなど検出—東電福島第１via ウォール・ストリート・ジャーナル
- High levels of strontium, tritium found in well water at Fukushima plant via The Asahi Shimbun