Plant workers scramble to prevent toxic water leak

Tokyo (CNN) — Workers at the crippled Fukushima Daiichi nuclear plant faced a difficult balancing act Tuesday as they struggled to keep reactors cool and prevent radioactive water from leaking into the ocean.

Water has been a key weapon in the battle to stave off a meltdown at the facility since a March 11 earthquake and tsunami knocked out cooling systems.

But officials say there’s a flip side to pumping and spraying tons of water to keep radioactive fuel from overheating: the water has to go somewhere.

The discovery of contaminated water in a maintenance tunnel has sparked fresh concerns about the possibility of additional radiation leaking from the plant.

“Now the focus is how to… remove the water and contain it safely,” Chief Cabinet Secretary Yukio Edano told reporters Tuesday.

Meanwhile, Japan’s nuclear safety agency said workers were using sandbags and concrete panels to keep the water inside the tunnel, which is located about 55 meters (180 feet) from the shore. The agency said there is no evidence of overflow yet.

Japanese officials and international experts have said they believe there’s been a partial meltdown at three of the plants six reactors.

“The high radiation levels on site seem to support that idea. There is no visual proof yet, but it’s increasingly likely there was partial fuel melting,” said Gary Was, a nuclear engineering expert at the University of Michigan.

And water runoff isn’t the only potential threat complicating efforts to contain the crisis.

Plant owner Tokyo Electric Power Company announced late Monday that tests detected low levels of plutonium in soil near the plant. The radioactive element is a reactor byproduct and part of the fuel mix in the No. 3 reactor.

The plutonium likely came from the plant, Edano said Tuesday.

“If we detect higher levels of plutonium, we have to take additional measures, so our intention for now is to carry on with the monitoring on-site,” he said.

The power company said it would increase monitoring in the area, but noted that the amount detected was equivalent to the amounts that fell on Japan following above-ground nuclear weapons tests by other countries in past decades, and posed no health risk to humans.

The element can be a serious health hazard if inhaled or ingested, but external exposure poses little health risk, according to the U.S. Environmental Protection Agency.

The company said the discovery would not change efforts to bring an end to the crisis at the plant, which has spread radioactive contamination across much of northern Japan.

Still, the water found in a maintenance tunnel leading to a turbine building connected with the plant’s No. 2 reactor remained radioactive enough to pose an immediate hazard, authorities reported Monday afternoon.

The 1,000 millisievert per hour reading was more than 330 times the dose an average person in a developed country receives per year and can result in vomiting and up to a 30 percent higher risk of cancer, according to the International Atomic Energy Agency. The level is also four times the top dose Japan’s Health Ministry has set for emergency workers struggling to control further emission of radioactive material from the damaged plant.

Edano told reporters Tuesday that officials hope to find workers to relieve those at the plant.

“On the ground at the nuclear power plant, the workers are working under very dangerous and very hard conditions, and I feel a great deal of respect for them,” he said.

As workers inside brave high radiation, the situation has also taken a significant toll beyond the complex’s six reactors.

Authorities have banned sale and transport of some vegetables grown in the area after tests detected radiation. Signs of contaminated tapwater prompted officials to tell residents in some areas to stop giving it to infants. And the government has said residents within a 20-kilometer (12-mile) radius of the plant must evacuate.

Still, some people have hunkered down and refused to leave. Authorities are going door-to-door — dressed head-to-toe in protective clothing — to make their case.

“We are explaining how serious the situation is to people,” said Kei Higuchi of the Japan Self-Defense Forces, “because radiation is something you can’t see with your eyes.”

The growing damages could have a steep pricetag for the embattled Tokyo Electric Power Company as farmers and others impacted by the disaster ask for compensation. Some have questioned whether Japan’s government will step in.

One government minister told reporters Tuesday that nationalizing the company could be an option.

“Of course, a debate on various options should be possible,” Japanese National Strategy Minister Koichiro Genba told reporters when asked whether the government was considering at least partially nationalizing the company.

Another topic Japanese officials are already beginning to debate is the country’s energy policy — and particularly its reliance on nuclear power.

“As part of the vision that will bring our nation hope for the future, we will further strongly promote clean energies,” Edano said Tuesday.

But he said fixing problems at the troubled Fukushima nuclear plant and reviewing the safety of the nation’s other plants take precedence.

“The first thing to do is contain the damage caused by the current crisis as soon as possible. … That is where our priority is,” he said.

CNN’s Yoko Wakatsuki, Whitney Hurst and Paula Hancocks contributed to this report.