TOKYO, April 4 (UPI) -- A Japanese utility released lower-level radioactive water into the sea Monday as workers searched for the source of leaks at the Fukushima Daiichi power plant.
Dyed powder was used to try to find the source, Kyodo News reported.
Tokyo Electric Power Co., operator of the nuclear plant crippled by a March 11 earthquake, said it began pouring 10,000 tons of water containing low-level radioactive substances into the Pacific Ocean to make room to store more dangerous water filling the No. 2 reactor building.
The utility also plans to release 1,500 tons of groundwater containing radioactive materials near the No. 5 and No. 6 reactors.
A government spokesman said the disposal is unavoidable and will pose ''no major health risk.''
Tokyo Electric also is considered putting silt barriers in the ocean to keep the highly radioactive water from spreading further, Kyodo reported.
The dangerous runoff risks overwhelming the generators powering cooling systems at two of the six reactors, The New York Times reported.
The water that will be released has about 100 times the legal limits of radiation, executives said, much less than the high levels of radiation found in seawater samples taken last week.
Fishing within 12 miles of the facility has been banned.
The silt barriers may be installed in areas where radioactive water is thought to be flowing into the ocean, said Hidehiko Nishiyama, a spokesman for Japan's nuclear safety agency.
"We would like to set up these fences as soon as possible," he said.
At least 11,828 people died in the 9-magnitude earthquake and subsequent tsunami and more than 15,500 are missing. Aftershocks continue to rattle the northeast region of Japan.