An aerial view shows Fukushima Daiichi nuclear power plant in Fukushima in this March 17, 2011 file photo. From R-L: Reactors 1 to 4 are seen in this picture taken more than 30km (18 miles) offshore from the site shortly before the start of the water-dropping operation. Plant operator Tokyo Electric Power Co said on March 27
, 2011 radiation 10 million times the usual level was detected in water that had accumulated at the No.2 reactor's turbine housing unit and a TEPCO official said that workers at the reactor had left to prevent exposure to radiation.?? (Xinhua/Reuters File Photo)TOKYO, April 3 (Xinhua) -- Japan's fight against its nuclear crisis suffered another setback on Sunday after efforts to cement a cracked concrete pit at a crippled nuclear reactor failed.The nuclear complex has been spewing radioactivity since March 11
, when a magnitude-9.0 earthquake and ensuing tsunami knocked out power
, disabling its cooling systems and allowing radiation to spill from the overheating reactors.On Saturday, crippled Fukushima Dai-ichi nuclear plant was found to have been discharging highly radioactive water into the Pacific Ocean.Later in the day, Tokyo Electric Power Co. (TEPCO) said it had found a crack in the pit at its No.2 reactor, which they believed was the source of the contaminated water.Soon after the discovery
, the plant's operator started filling the pit with cement to seal the crack and prevent more contaminated water from seeping into the ocean.However, after pouring concrete into the pit with a 20-centimeter crack
, workers found the crack was still discharging heavy doses of radiation, which was over 4
,000 times the legal limit.After the failed attempt, TEPCO's engineers are struggling to devise new tactics such as using water-absorbent polymer to prevent further leakage of contaminated water into the sea.
