FUKUSHIMA, Japan, Feb. 20 (UPI) -- Tokyo Electric (Tepco) officials say they discovered another leaking tank, used to store highly radioactive nuclear waste water, at the Fukushima power plant.
Plant operators say no new water is being pumped into the damaged tank, and that the leak is stopped. But not before roughly 100 metric tons of the toxic water overflowed after a valve was mistakenly left open.
"We apologise for worrying the public with such a leak," Tepco spokesman Masayuki Ono told reporters on Wednesday. "Water is unlikely to have reached the ocean as there is no drainage in that tank area."
Mr. Ono added that cleanup specialists at the company were currently in the process of "recovering the leaked water and the earth it has contaminated."
The escaped waste water's toxicity reading measured at 230 million becquerels per liter. A becquerel is an internationally-agreed-upon unit used to measure radioactivity. The World Health Organization potable water shouldn't exceed a reading of 10 becquerels per litre.
The Fukushima nuclear power plant has suffered a litany of problems since it was damaged during the earthquake and tsunami that devastated Japan's Pacific coast in 2011. Last summer 300 metric tons of radioactive water spilled from a different tank.