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During the next six months, a new study will be made public about ways to improve emergency planning at Indian Point, the nation's most populated nuclear site. Two nuclear power plants, Indian Point units 2 & 3, produce over 1000 MWe each and are a vital part of the energy supply of the Metropolitan New York City area. These plants, about 24 miles north of New York City, are the lowest cost electricity producers in this area. However, over 305, 000 people live within the Emergency Planning Zone (EPZ), roughly a circle ten miles in radius, and roads are often quite congested. American Airlines flight 11 flew near these plants as it went down the Hudson Valley on its way to crashing into the World Trade Center and the memory of the Katrina tragedy is fresh in our minds. Therefore an effective emergency plan is an important consideration for the people in this area.

This new study will show that the health consequences of a major release of radioactive material can be made to be very limited, even at this most challenging of sites. Unlike other risk analyses, which are based on unintended accidents, a willful act of terrorism was assumed as the cause of a large release of radioactive material. It was assumed that terrorists successfully breached one of the massive containment buildings and then caused reactor meltdown. A successful terrorist attack is highly unlikely. Nonetheless, this was the starting point for these advanced emergency planning analyses. This study examined a wide range of potential health effects from exposure to radiation including early fatalities, early injuries, and long-term latent cancer fatalities.

An important result of these analyses was the determination of the range of the early fatality risk. Similar to many previous analyses, it was shown that this risk decreases rapidly with distance, with most of this risk within one mile of the point of release and virtually all within two miles. The terrorist scenario that was most likely to cause offsite early fatality consequences had the shortest time between reactor scram and a release entering the environment, about two hours. However, even this short time would still allow an effective evacuation on foot. At normal walking speeds of about 2.5 to 3 mph, pedestrians would soon be outside of the two-mile early fatality zone. Anybody who leaves before the onset of the release of radioactive material to the environment and travels away from the site at normal walking speeds, is not expected to become an early fatality. Most people are expected to evacuate in vehicles. Street -by- street traffic analyses show that vehicular evacuation today would be very slow. However, these same traffic analyses have been used to identify simple traffic control actions that would speed the evacuation up. Because of these traffic control improvements, the delay between reactor scram and release to the environment during which time people would begin their evacuation, and the short range of the early fatality risk, the calculated early fatality risk with a vehicular evacuation is also expected to be quite small.

The range of the early injury risk is approximately four miles. In this middle zone, two to four miles, people should first take shelter and some may be evacuated later if local radiation levels warranted this. The National Council on Radiation Protection and Measurements has identified a simple ad hoc protective action that people can take: Breath through a wet handkerchief and reduce your inhalation doses by a factor of 10. Our examination shows that a ten-fold reduction in inhalation doses virtually eliminates all radiation induced respiratory injuries in the early injury zone. Another ad hoc protective measure is to cover one's skin with a towel, etc., which would essentially eliminate skin doses. These ad hoc measures can be implemented by the public itself without relying on emergency responders. The combination of sheltering, ad hoc protective measures, and localized evacuations is expected to limit the early injury risk to very small numbers. The combination of sheltering and ad hoc protective measures is also a very effective response in the inner two-mile early fatality zone if poor road conditions cause close-in people to delay their evacuation.

Beyond four miles there would be no appreciable early fatality or early injury risks and long term health effects would be the remaining health concern. In this outer area taking shelter would be the preferred response. The great majority of the people in the EPZ would be advised to take shelter while those in the early fatality zone promptly evacuated. At worst, latent health effects would be a very small fraction of the normal background cancer rate, perhaps too small to measure.

Very small health effects from large releases of radioactive material may be in conflict with some people's perceptions of nuclear power's health risks. However two other events support this conclusion. The Chernobyl accident did not produce early fatalities among the general public, even though they did not evacuate. Fires at Chernobyl lofted the radioactive plume to great heights so that the concentration of radioactive material outside of the site was rather low. Similarly, low concentrations of radioactive material would occur within a short distance from a damaged US plant, whereas it takes high concentrations to cause an early fatality. Such high concentrations were experienced by the fire fighters who came on the Chernobyl site and by people who flew over this site in a helicopter. Many of these highly exposed people later became early fatalities. There have been early injuries from Chernobyl, particularly thyroid injuries. However, about 90% of the thyroid injuries in the Ukraine came from drinking contaminated milk where the grim choice was drink the milk or starve. Food interdiction plans at all U.S. nuclear power plants would prevent such injuries. A recent UN study of the long term health effects of Chernobyl, a 20 year retrospective, shows that earlier projected long term health effects were overly conservative. In any case, previous and present calculated long term health effects are a small fraction of background cancer fatality rates. The largest effects of the Chernobyl accident are the land contamination that it caused and health effects, not from actual irradiation, but from the fear of being irradiated.

There have also been recent analyses by Lawrence Livermore Laboratory on the potential effects of dirty bombs. The conclusion here was that health effects from exposure to radiation would be very small, but the economic losses could be huge. It appears that both Chernobyl experience and the analyses of dirty bombs support the notion that offsite health effects from large releases of radioactive material is very limited.

Large releases of radioactive material would not be a major off site health risk. Such events would be dominated by economic consequences.