Are Fears of a Catastrophic Nuclear Meltdown in Japan Warranted?

This is a rush transcript from "Hannity," March 14, 2011. This copy may not be in its final form and may be updated.

SEAN HANNITY, HOST: And tonight fears of a catastrophic meltdown at a Japanese nuclear power plant are rising.

Now in the wake of Friday's massive earthquake, a series of explosions have crippled efforts to reduce the temperature inside those reactors. And the latest explosion occurred just over an hour ago.

Now seawater is being used to cool the rods, but late Monday night in Japan, the water level dropped and the rods were exposed. Now this poses serious health risks and dramatically increases the chances of a total meltdown.

Now also today, we learned that crewmembers of the USS Reagan were exposed to radiation while on a relief mission. Now reports indicate that the exposure occurred when U.S. helicopters flew through a cloud of a radioactive dust although the exposure being described as low leveled and test did not detect any contamination after they washed with soap and water, the sailors are being closely monitored.

Joining me now with the very latest on the developing situation are Jay Lehr from The Heartland Institute, Ira Helfand, a nuclear expert, member of the board of Physicians for Social Responsibility, and nuclear safety consultant Margaret Harding.

Thank you both -- Jay, I'm looking at not only the contamination story of the USS Reagan Navy crewmembers but, you know, "this is a race against time." You know, "Japan's frantic efforts to avoid a meltdown." Some people say, "we were told not to breathe the air, it's scary." How realistic is this threat?

JAY LEHR, THE HEARTLAND INSTITUTE: Sean, it is not at all realistic. I can tell you with the utmost confidence there will not be a health impact of anything that is going on at the Fukushima power plant. A meltdown, people interpret it as virtually a disaster, and explosion, destruction like an atomic bomb that is not true at all. A meltdown just means that the cooling of the rods has failed. The temperature is higher than can be controlled in order to create the hot water that ultimately flashes to steam and turns a turbine. So, they immediately install rods to bring the radioactive decay down to subcritical but they have leftover heat and residual radiation that has to be brought under control, it will happen naturally within a few days. They are doing the best they can.

But a total meltdown has only occurred at Three Mile Island back in 1979. That was a disaster of a nuclear plant considered 10 times more serious than Fukushima. And the rods actually did melt down, fell to the floor of the reactor building. And they only melted five-eight of an inch into five inches of steel before they cooled and the situation stopped. And as you well know, there were no health impacts from Three Mile Island.

There will not be any health impacts here. The nuclear engineers in Japan are doing a magnificent job under a situation that could never be expected. And the public in Japan has enough to worry about with a horrible disaster without worrying that there is going to be a nuclear explosion.

HANNITY: Let me bring Ira in here. Now, the Japanese nuclear safety agency rated the damage at the nuclear power plant in Fukushima at a four on a scale of one to seven. Each number being 10 times worst than the prior one. For example, Three Mile Island was a five. And Chernobyl rated as the seven. Do you agree with the assessment of Jay Lehr?

IRA HELFAND, NUCLEAR EXPERT: Well, no, not at all. I mean, it was rated as a four, two days ago. And a lot of very bad things have happened since then. We don't know what is going to happen. There may not be a significant breach of containment at either any of these three reactors, but there may be. And that's the point. For the last three days, the people who occupy this plant, have not known what has been going on. They have been doing a spectacular job, but they've been working in the dark. They've been using techniques which are not in any of the playbooks. Using fire trucks to pump seawater into a reactor which you know is going to destroy the reactor. It's something that has never been done before and is never been contemplated before. And it is not working really well either which is why we keep having these periodic increases in the amount of fuel that's melting down.

HANNITY: Well, there's always a possibility -- but Margaret, let me bring you in here. As, you know, by all accounts, you know, they even built this facility which was built number of decades ago to withstand an 8.2 magnitude earthquake. There is, as I understand what they're saying is a ton of redundancy and protections that they put in place here, you know, even envisioning a worst-case scenario, your thoughts on where we are right now, what we can expect.

MARGARET HARDING, NUCLEAR SAFETY CONSULTANT: Well, that's correct. First I'd like to say that on behalf of the American Nuclear Society, that our hearts go out to what is happening in Japan. And the earthquake and the tsunami and the devastation. I especially want to congratulate and honor the workers at the plants whose families and homes have been lost, and yet they've stayed on the job.

That said, you are absolutely right. There's huge defense and depth on these plans. They were designed to operate through an earthquake, an 8.2. They survived this earthquake, the tsunami was what took out some of the backup systems. But the ultimate backup has always been the reactor vessel and the containment which are working. In addition, remember that the seawater option was built into the plant. This is not something that was not anticipated. It is of course something you don't want to do. You don't want to put seawater into the facility. But it was planned as an ultimate backup if you needed it and it is working.

HANNITY: All right. Jay, we keep hearing "meltdown" and I know when we talk about nuclear anything, that I assume that people's minds go towards nuclear explosion of some kind.

LEHR: There's no question about that Sean. A meltdown is basically a nuclear engineering term which simply means that the heat from the radioactive decay is greater than we want it to be in order to operate --

HANNITY: But the fear is to release a radiation, is it not?

LEHR: It is but we have a containment structure that is not likely to release the radiation. And if it did release the radiation, most of the radioactive particles have a very short half life. Chernobyl was a number seven as you said. It had no containment building. It totally exploded. There was a cloud of radiation that they said was going to kill tens of thousands of people and deform children.

Ten years after the accident, the U.N. produced a 1,200-page report pointing out that there was no long-term impact on health from anybody away from the plant due to the radiation cloud. There were 1,000 cases of leukemia in the village right surrounding Chernobyl, and 998 of them were cured.

So, this idea of this radioactive cloud like a nuclear bomb is totally false. And puts stress on a population --both our country and their country -- that is totally unwarned.

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