Tepco took months to release record strontium readings at Fukushima

By Mari Saito TOKYO (Reuters) – The operator of Japan's wrecked Fukushima nuclear plant knew about record high measurements of a dangerous isotope in groundwater at the plant for five months before telling the country's nuclear watchdog, a regulatory official told Reuters. Tokyo Electric Power Co (Tepco) said late on Wednesday it detected 5 million becquerels per liter of radioactive strontium-90 in a sample from a groundwater well about 25 meters from the ocean last September. A Tepco spokesman said there was uncertainty about the reliability and accuracy of the September strontium reading, so the utility decided to re-examine the data. Shinji Kinjo, head of a Nuclear Regulation Authority (NRA) taskforce on contaminated water issues at Fukushima, told Reuters he had not heard about the record high strontium reading until this month.