Authorities discovered radioactive water from the damaged Fukushima Daiichi nuclear power plant in Japan flowing into the sea from a crack in the No. 2 reactor Saturday.

A crack measuring almost eight inches long was discovered in the concrete wall of a pit where power cables are stored, according to Tokyo Electric Power Co. (Tepco), the plant’s owner. The area above where the water was pooling and leaking into the ocean had a radioactivity reading of 1,000 millisieverts per hour.

The maximum radiation level to which workers can legally be exposed is 250 millisieverts per hour.

Hidehiko Nishiyama, deputy director general of Japan’s Nuclear and Industrial Safety Agency, said his agency has instructed Tepco to search the facility for other potential leaks.

“Today we found highly irradiated water in the pit where the electricity cables are contained,” Nishiyama said. “It seems that there is a crack on the side of the concrete wall of the pit. Some water is spilling out of the crack to the sea.”

At a news conference Saturday, a Tepco spokesman said the company plans to pour concrete into the crack to try to stop the leak.

The discovery came as Tepco was considering broader steps to deal with the burgeoning crisis. Among the latest ideas, officials said, are pumping nitrogen into reactors Nos. 1 and 3 to try to prevent explosions of hydrogen gas that is building up and using an artificial floating island to store contaminated water that has pooled inside the facility.

The reactors, when operating properly, are filled with nitrogen. Officials fear the nitrogen level might have decreased during explosions inside the power plant during the early days of the crisis, after the March 11 earthquake and tsunami knocked out the critical cooling systems.

As Tepco continued to struggle to contain the radiation leaks, a 15-member advance team from the U.S. military’s radiation control unit arrived at Yokota Air Base. Kyodo News reported that 140 more Marines from the unit are on the way. The force can monitor radiation levels, help with search-and-rescue operations and deal with decontamination, the wire service reported.

(Washington Post)