5 Décembre 2012
December 4, 2012
Tokyo Electric Power Co. may string nets across its port at the stricken Fukushima No. 1 nuclear power plant to prevent fish contaminated with radiation from reaching the sea.
In surveys conducted through October, greenling caught in the littoral zone of the Otagawa river, about 20 kilometers north of the crippled plant, showed relatively low figures, with 1,350 becquerels per kilogram the maximum. Many greenlings had readings of around 100 becquerels.
But TEPCO also found in the port that species of Conger eel had 15,500 becquerels and other species of fish had 4,200 bequerels, sources said. Conger eels from outside the port posted 100 becquerels or lower.
One hundred becquerels is the standard [read the top limit] for common foodstuffs
At the request of local fishery cooperatives, TEPCO has been studying ways to contain fish in the port.
Sources said the company is considering setting up a 2-kilometer net at the mouth of the port and along the inside of the port’s levees. The measure would be accompanied with dredging of mud in the port.
A similar net was rigged up in 1974 in Minamata Bay to prevent mercury-tainted fish from spreading outside the bay. The net stretched 4.4 kilometers at one point. It was removed after the bay was declared safe in 1997.
At Fukushima, a vast amount of contaminated water that includes radioactive substances has been discharged into the sea since the nuclear disaster triggered by the March 11, 2011, Great East Japan Earthquake and tsunami.
“We have been asking TEPCO to close the port after receiving data showing high levels of contamination,” said an official at a local fisheries cooperative. "There are openable nets that will allow dredgers to enter. TEPCO's response is too slow.”
By MASAKAZU HONDA/ Staff Writer