On Sunday, May 26, 2002, the New York Times Magazine featured an 8,000-word cover story by staff reporter Bill Keller entitled “Nuclear Nightmares.” I first heard about this article on an early morning Public Radio interview with Keller broadcast over KPCC out of Pasadena City College, northeast of Los Angeles. The short interview focused on the last few paragraphs of Keller’s article wherein he reported the results of a computer model created by Matthew McKinzie, who is a staff scientist at the Natural Resources Defense Council (NRDC).

It is quite useful to understand just who Matthew McKinzie and the NRDC really are. The NRDC is a Washington, D.C., based environmental group that claims approximately 500,000 members worldwide and a staff of “respected scientists, lawyers, and environmental specialists.” It has offices in New York, Washington, Los Angeles and San Francisco.

In fact, the NRDC is a left-wing organization that has been trying to eliminate anything nuclear since its inception in 1970. Dr. McKinzie was initially a researcher at Los Alamos. Apparently his left-wing politics lead him to get caught up in the so-called “international peace movement” that was surreptitiously promoted and funded by the international communist movement of that period, and he ended up as a “staff scientist” with the NRDC. At the NRDC, McKinzie focused on generating computer programs that purport to demonstrate the effects of nuclear explosions on civilian populations and municipal infrastructures.

Although I have not had the opportunity to examine McKinzie’s specific computer models, physics is a two-way street. One can start with a set of conditions, apply them to a mathematical model that contains certain assumptions, and generate a result based upon those conditions, the assumptions, and the math and physics contained in the model. Or, one can start with a result, apply both the original conditions and the underlying math and physics, and from this one can generate the assumptions used in the model.

This “reverse engineering” approach has its pitfalls, since the math and physics one applies, while certainly one of the constants in this problem, can be from one of several basic approaches to the original problem. Nevertheless, it is quite possible, with very little effort, to zero in on the basic assumptions McKinzie has used in his models.

Another interesting point about Dr. McKinzie and the NRDC, is that he has been applying these models to various scenarios as requested by other members of the anti-nuclear left: to studies in Canada, in Pakistan, and elsewhere. Always with the same message: Nuclear is bad.

The predicted results presented by McKinzie and his fellow travelers are always horrific, always unthinkable, always obvious justification for doing away with anything nuclear.

Here is the predicted result, taken directly from Keller’s article:

Here is how McKinzie arrived at these results. First, he assumed that the area surrounding the explosion had a certain population density. Whatever exact figure he used, I have no quarrel with the number; I am certain it was in the ballpark. Then he assumed a blast effect calculated from previous experiments, most accomplished in the 1950s at the Nevada test site. He probably modified these results to account for more modern technology, and since none of these tests were ever performed on such a small device, he modified his assumptions to accommodate this fact.

I take issue with several parts of this process. The measurements made in the 1950s were taken at a significant distance from the blasts. They were made with equipment that was relatively primitive by today’s standards. The explosive devices were crude by today’s standards, and there really is no way to extrapolate the results of these explosions to what happens with a modern 1-kiloton device. Furthermore, these measurements were made across a flat expanse of desert, not in a city environment, surrounded by substantial high-rise buildings.

This really is the key. If you take the simple results from the 1950s tests, extrapolate them down to 1 kiloton, and apply the results to the presumed population distributed across a half-mile radius, the predicted results will be very much like what McKinzie predicted.

The moment you insert dozens of substantial buildings, however, most built with concrete and steel construction, the entire problem changes radically. The force of any blast is transmitted through the air – no air, no blast effect, despite what you see on sci-fi flicks. As this spherical cauldron expands during the first microseconds, almost immediately it encounters very dense walls of steel reinforced concrete. The closest buildings will not be gutted so much as destroyed. The heat probably will vaporize sufficient material at the bases of these buildings to cause them to collapse.

Considering just the damage without the blast, the buildings probably would tend to collapse inward, tilting toward the center. In our scenario, however, a portion of the blast will be funneled upward, somewhat like a chimney, expanding as it rises. This will tend to counter the inward falling tendency, so that the buildings will tend to fall into their footprint. It may also be that some of the taller buildings will actually be forced outward by the rising blast.

By the second or third layer of buildings, the blast will have been substantially absorbed in the horizontal plane. The rising blast plume will certainly affect the building upper floors, but the buildings in direct contact with the blast are goners anyway.

Of course the people in the immediate vicinity will be killed. But if you are two or three buildings away, especially if these buildings are substantial, you may not even be hurt by the blast.

There will be an initial flood of neutrons, and they will kill if they go through you, even if you are a mile away. Thus, along the thoroughfares directly exposed to the blast, there will be some serious radiation damage, and they may also funnel the blast to a greater distance as well. The several layers of reinforced concrete buildings will stop the neutrons in other directions. Immediately following the neutrons will be gamma (high energy photons) and beta (high energy electrons) radiation. The gamma will also funnel along the thoroughfares, but with considerable less damage. It will be completely absorbed by the first layer of concrete. Beta can be stopped by a few inches of air or your skin. Unless you are directly exposed to a great deal, beta will cause no problem. Alpha is really not radiation at all, but helium nuclei. It is only dangerous if actually taken inside the body. Typically, it is present in the fallout from a nuclear explosion.

So far we have some pretty serious damage out to maybe three buildings and along the exposed thoroughfares. We have some radiation damage from neutrons and gamma along the same thoroughfares, and some localized beta damage.

The fallout is totally dependent upon the kind of explosion: basically, how dirty it was. Small nukes are especially designed to be very clean, that is without any major radiation after-effects. Thus, the blast plume that shoots up through the buildings will be relatively clean; it will contain little alpha producing substances.

The bottom line is that such a bomb exploded on a typical New York street corner (Times Square in Keller’s example) will not produce anywhere near the level of damage predicted by McKinzie. In fact, a 10-kiloton bomb will not produce the kind of damage he predicted!

So much for NRDC science.

Keller opened his article with an account of a conversation he had with Russian nuclear physicist Vladimir Shikalov. Shikalov, who had participated in the Chernobyl cleanup following the 1986 reactor accident, described a possible terrorist scenario where about a cup of radioactive cesium-137 would be surreptitiously sprayed into the air inside Disneyland. Keller estimated that this action probably would shut down the place for good and constitute a “staggering strike at Americans’ sense of innocence.”

Shikalov believes – correctly – that most people are irrationally afraid of radiation. He indicated that he would have no problem visiting Disneyland following such an attack. He thought he might carry his own food and drink and destroy his clothing afterward, as a general safety precaution, but he firmly believes that American’s fear of radiation would push us to an extreme reaction to such an attack.

To his credit, Keller included this story in his article, but he soon left its common- sense view for more extreme anti-nuclear views like McKinzie’s. I responded to Keller’s article in some detail on The New York Times discussion board linked to the article. In response, I received an email from which I have extracted the following passage:

I would appreciate somebody answering this guy’s question, because I’m not sure I have an answer that makes sense.