Monday's coolant leak at a nuclear plant in Tsuruga, Fukui Prefecture, Japan caused radiation levels inside the reactor building to shoot up 11,500 times the legal safety limit. The finding was announced by Japan Atomic Power Co. (Genden), which operates the Tsuruga nuclear power station. Massive leakage of radioactive cooling water occurred Monday at the station's No. 2 reactor. Genden initially said the level of contamination was at least 1,000 becquerels, 250 times the limit. The firm corrected the figure to 46,000 becquerels for Monday. The disparity was due to a lack of accurate data, Genden said.