Tokyo residence watch as half of a city block is left in the dark during a rolling black out in the Shinjuku region of Tokya, March 29, 2011. Tokyo Electric Power Co. implemented rolling blackout to conserve power in the wake of the Fukushima nuclear power plant incident. UPI/Keizo Mori | License Photo
TOKYO, April 1 (UPI) -- The crisis at Japan's disabled Fukushima nuclear plant assumed another dimension Friday with detection of groundwater contamination near a reactor.
With radioactive Iodine-131 rising to its highest levels in Pacific Ocean waters near the plant, latest tests Thursday night detected groundwater containing radioactive iodine 10,000 times the legal limit near the No. 1 reactor's turbine building, Kyodo News reported.
The Nuclear and Industrial Safety Agency warned Tokyo Electric Power Co. mistakes in its data are damaging its credibility, Kyodo said. The company admitted a programming mistake made its figures on substances other than radioactive iodine unreliable.
''TEPCO faces a grave situation as it is failing to live up to the expectations of people who are very worried by the company. Its data should be trustworthy,'' Hidehiko Nishiyama, a spokesman for the agency, said Friday.
The detection of groundwater contamination was the first since the six-reactor plant was hit by the March 11 magnitude-9 earthquake and a trailing giant tsunami. However, the readings may be reviewed.
It was not clear how water from the reactor building could have seeped into the ground. Similarly, it is as yet not clear how any leak from the reactors could have seeped into sea waters.
The first four reactors, including No. 1, damaged severely and continuously leaking radioactive substances with the failure of their cooling systems, are already scheduled to be de-commissioned or never to be used again. It is likely the cores at Nos. 1, 2 and 3 reactors were damaged, causing them to release radioactive substances, and the fuel rods at No. 4 reactor, kept in a spent fuel pool, are believed to have been exposed after its cooling functions failed.
Additionally, the turbine buildings of some of the reactors are reported to be flooded with contaminated water, making it difficult to pump them out.
Commenting on the detection of groundwater contamination at such high levels, a TEPCO official was quoted as saying: "We're aware this is an extremely high figure.''
The International Atomic Energy Agency asked Japan to look into radioactive contamination outside the 20-kilometer (12.5 mile) evacuation zone around the plant, as soil sample readings in the village of Iiate, 40 kilometers (25 miles) from the plant, exceeded the limit set for evacuation.