Smoke billows from the Fukushima Daiichi plant. (Photo from Flickr via daveeza)

Tokyo Electric Power Co. has already unsuccessfully tried to plug the 8-inch crack they found in near reactor No. 2 with concrete.

The Los Angeles Times reports:

Workers pumped cement into the shaft Saturday, but by the end of the day, the flow of water into the ocean had not diminished. Engineers speculated that the water was preventing the cement from setting, allowing it to be washed away.

Tepco officials said that on Sunday morning they would explore using a polymer — a type of quick-setting plastic — to plug the leak.

Specialists say the crack likely is from the magnitude 9 earthquake that rocked Japan on March 11. Since the earthquake, Fukushima workers have flooded the nuclear reactors to keep them cool after the plant's backup power system failed. This cooling method has left TEPCO with an excess of contaminated water, and some of that water has ended up in the sea.

“The more water they add, the more problems they are generating,” said Satoshi Sato, a former engineer with General Electric and a consultant to the nuclear energy industry. “It’s just a matter of time before the leaks into the ocean grow.”

Japanese Prime Minister Naoto Kan visited the area near the Fukushima plant Saturday to show his support for the effort there to control the reactors.

Fukushima area residents were told that they may not be able to return home for months.

Some have criticized the Japanese government for paying too much attention to the plant and not enough attention to the country's affected residents.

High levels of radiation have been found in the ocean near the plant for days now. The crack is the first identified possible source of the contamination.

The New York Times reports:

The space directly above the water leaking into the sea had a radiation reading of more than 1,000 millisieverts per hour, Mr. Nishiyama said, a level that could be dangerous to humans. Tests of the water within the pit later showed the presence of one million becquerels per liter of iodine 131, a radioactive substance. That level of iodine is 10,000 times what is normal for water at the plant. However, iodine 131 has a half life of about eight days.

Mr. Nishiyama also said that higher than normal levels of radioactive materials were detected about 25 miles south of the Fukushima plant, much farther than had previously been reported.