Ch. 4: Evacuation

CHANGED EVACUATION REQUIREMENTS

The most threatening Soviet nuclear warheads in the mid-1970s were multi-megaton, such as single warheads of approximately 20 megatons carried by each of over 250 SS-18s. About half of these huge Russian warheads would have hit within a quarter of a mile or less of their intended targets - close enough to destroy a missile in its hardened silo. Today's improved Russian warheads have a 50-50 probability of hitting within a few hundred feet of their aiming points. With such accuracy, multi- megaton warheads are not needed to destroy very hard targets, especially missiles in their blast-protective silos.

Soviet strategy continues to stress the destruction of military targets, in order to minimize Russian losses from retaliatory strikes. This logical, long-established Soviet strategy is emphasized in numerous authoritative Russian books, including the three editions of Soviet Military Strategy by Marshall of the Soviet Union V. D. Sokolovskiy.

One result of this logical strategy has been the replacement of huge Soviet warheads by numerous, much smaller, much more accurate warheads. In 1990 almost all large missiles have several Multiple Independently-targetted Reentry Vehicles (MIRVed) warheads. Soviet warheads - especially the 10 warheads of 500 kilotons each carried by most SS-18s - could destroy almost all important U.S. fixed military installations, and also almost all U.S. command and control facilities, airport runways longer than 7,000 feet, major seaports, and the factories and refineries that are the basis of our military power. (Although an all-out Soviet attack could destroy almost all missile silos and missiles in them, a first-strike attack is deterred in part by the possibility that most U.S. missiles in silos would be launched on warning and would be in space, on their trajectories toward Russian targets, before Soviet warheads could reach their silos.)

How should your plans either to evacuate during a worsening crisis, or to remain in your home area, be influenced by the dramatic changes in the Soviet nuclear arsenal? Some of these changes are indicated by Fig. 4.1, that incorporates information on the dimensions of the stabilized clouds of one megaton and 200 kiloton explosions, from reference 6, The Effects of Nuclear Weapons, 1977, and similar information on a 20-megaton cloud derived from a graph on page 20 of The Effects on the Atmosphere qf a Major Nuclear Exchange, by the Committee on the Atmospheric Effects of Nuclear Explosions, National Research Council, National Academy Press, Washington, D.C. 1985. (This NRC graph is based on Ballistic Missile Organization 83-5 Part 1, dated 29 September 1983, a report that is not generally available.)

The air bursting of one of the probably few 20-megaton warheads carried by Soviet ICBMs would destroy typical American homes up to about 16 miles from ground zero. In contrast, the air bursting of an approximately 1-megaton warhead - one of the large warheads in today's Soviet arsenal - would destroy most homes within a roughly circular area having a radius of"only" about 5 miles. So, if you take into consideration the advantages to Soviets of arming their largest ICBMs with several very accurate smaller warheads, each capable of destroying a militarily important target, you may logically conclude that unless your home is closer than 10 miles from the nearest probable target, you need not evacuate to avoid blast and fire dangers.

Your planning to avoid incapacitating or fatal exposure to fallout radiation will involve more uncertainties than will your plans to avoid blast and fire dangers. The high altitude winds that carry fallout farthest before deposition usually blow from west to east. Therefore, in most areas your chances of avoiding extremely dangerous radiation dangers are improved if

you evacuate westward to an area away from likely nearby targets. However, since no one can foretell with certainty in what directions future winds will blow, your plans to remain where you live, or your crisis evacuation plans should include building, improving, or utilizing high-protection-factor shelter, as explained in following chapters.

If you live near a target the destruction of which has high priority in Soviet war-winning strategy, then a decade or so ago it quite likely was targeted by a 20-MT warhead. Fig. 4.1 shows the awesome size of the stabilized radioactive cloud from a 20-MT air burst. This cloud would expand in minutes to this huge size in the thin air of the stratosphere, would contain only extremely small particles almost all of which would remain airborne for weeks to years, and would result in no fallout deposition that would promptly incapacitate exposed people.

A 20-MT surface burst or near-surface burst would produce a stabilized radioactive cloud extending almost as far in all directions from GZ as would a 20-MT air burst. Its tremendous fireball would "suck up" millions of tons of pulverized rock and would contaminate those particles with its radioactive material. Fallout particles as big as marbles6 would fall from the stabilized cloud to the ground in minutes. Very heavy fallout could be deposited as far as 18 miles upwind from such a 20-MT explosion, with heavy fallout, capable of causing fatalities within days to weeks, extending downwind for several hundred miles.

A 1-MT surface burst,Fig. 4.1. would produce a stabilized fallout cloud unlikely to result in fallout being deposited in the upwind or crosswind directions from GZ beyond the range of the explosion's home-destroying blast effects. Clearly, the risk of your being endangered by very heavy fallout if you remain 6 miles from GZ of a 1-MT surface burst, and happen to be upwind or crosswind from GZ, is less than the risk you would have run a decade ago if you had stayed 18 miles upwind or crosswind from the same target, which had been destroyed by a 20- MT surface or near-surface burst.

Highest-risk areas are those in which buildings are likely to be destroyed by blast and/or fire, and/or where a person in the open for the first two weeks after fallout deposition would receive a total radiation dose of 10,000 R or more. The largest highest-risk areas would be those within our five Minuteman missile fields, within a few miles all around them, and for up to about 150 miles downwind. These huge highest- risk areas are indicated by five of the largest black fallout patterns on Fig. 4.2.

Fig. 4.2 is an outdated, computer-drawn fallout map based on a multi-megaton attack considered credible 10 years ago. (An updated, unclassified fallout map of the United States, showing radiation doses to persons in the open, is not available.) This outdated attack included 113 surface bursts of 20 megatons each on urban and industrial targets, an unlikely assumption similar to those used in making some official civil defense risk-area maps that assumed surface bursts on all targets nationwide. Employing all surface bursts makes little sense to the military, because air bursting the same weapons would destroy most military installations, as well as factories and other urban and industrial assets, over approximately twice as large an area.

As will be explained later, to survive in such areas people would have to stay inside very good shelters for several weeks, or, after two weeks or more, leave very good shelters and drive in a few hours to an area relatively free of fallout dangers. A "very good" fallout shelter is one that reduces the radiation dose received by its occupants to less than 1/200th of the dose they would have received outdoors during the same period. If the two-week dose outdoors were 20,000 R, such a shelter with a protection factor of 200 (PF 200) would prevent each occupant from receiving a dose greater than 100 R -- not enough to incapacitate. Even a completely below ground home basement, unless greatly improved as described in Chapter 5, would give entirely inadequate protection.

High-risk fallout areas are those where the two- week dose outdoors is between 5,000 and 10,000 R. In such areas, good fallout shelters would be essential, supplied at least with adequate water and baby food for two weeks. Furthermore, survivors would have to remain inside shelters for most of each day for several additional weeks.

The radiation dangers in the shaded areas of the map are shown decreasing as the distances from the explosions increase. This generally is the case, although sometimes rain or snow' carries radioactive particles to the ground, producing "rainouts" of exceptionally heavy fallout farther downwind. Furthermore, this computer-drawn map made at Oak Ridge National Laboratory does not indicate the very dangerous fallout near the isolated surface bursts. Although the most dangerous fallout would be carried by high- altitude winds that usually blow from west to east, such simplified fallout patterns as those shown should be used only as rough guides to help improve chances of evacuating a probable blast area or very heavy fallout area and going to a less dangerous area. Wind directions are undependable; an enemy's targeting can be unexpected; weapons can miss. A prudent citizen, nomatter where he is, should try to build a shelter that gives excellent protection against fallout radiation.

A major disadvantage of all types of risk-area maps is the fact that poorly informed people often misinterpret them and conclude that if they are outside a mapped risk area, they are relatively safe from blast, fire, and even deadly fallout dangers.

Another reason for not placing much reliance on risk-area maps like Fig. 4.2 is that such unclassified maps available in 1986 are based on the largest attacks considered possible a decade ago. In 1986 the sizes of Soviet warheads are much smaller, their numbers are much larger, and their total megatonage and cap ability to produce fallout remain about the same as 10 years ago.

The outdated attack scenario used in producing Fig. 4.2 also involved the surface bursting of multi-megaton warheads totaling 3,190 megatons on military targets, including over 2,000 megatons logically surface bursted on our five Minuteman missile fields. Such an attackon our missile fields would produce about the same amount of fallout as is shown in Fig. 4.2. Today, however, heavy fallout from our missile fields would extend somewhat shorter distances downwind, because of the lower heights of the stabilized radioactive clouds from one-megaton and smaller surface and near-surface bursts, as compared to those of multi-megaton warheads that would have been exploded 10 years ago, at a time when a 20-megaton warhead was typical of the Soviet nuclear ICBM arsenal.

In 1986 hundreds of targets besides those indicated in Fig. 4.2 might be hit, but the total area of the United States subjected to lethal falloutprobably would be less than is shown in Fig. 4.2. To maximize areas of destruction by blast and fire, most targets in urban and/or industrial areas would be attacked with air bursts, which would produce little or no promptly lethal or incapacitating fallout - except perhaps in scattered "hot spots" where rain-outs or snow-outs could bring huge numbers of tiny, very radioactive particles to earth within hours after the air bursting of today's kiloton-range Soviet warheads. And since most Americans live far away from "hard" targets - especially far from missile silos, downwind from which extremely heavy fallout is likely - most of us living in or near high-risk areas probably would be endangered primarily by blast and fire, not fallout, in the event of a Soviet attack.

WHETHER TO EVACUATE

Let's assume that Russian cities were being evacuated, or that tactical nuclear weapons were beginning to be used in what had been an overseas conventional war involving the United States. In such a worsening crisis, most Americans could improve their survival chances by getting out of the highest-risk and high-risk areas.

U.S. capabilities for war-crisis evacuation are poor and tending to worsen. Several years ago, out of the approximately 3,100 evacuation plans required nationwide, about 1,500 had been made, and these involved only about one third of Americans living in risk areas. By 1986 some cities and states had abandoned their war-crisis evacuation plans; most still have plans that would save millionsif ordered in time during a crisis lasting at least a few days and completed before the attack. Who would order an evacuation under threat of attack, and under what circumstances, remain unanswered questions. Furthermore, compulsory evacuation during a war crisis was not and is not part of any official American evacuation plan. So, if you believe that a nuclear attack on the United States is possible and want to improve your chances of surviving, then well before a desperate crisis arises you had better either make preparations to improve your and your family's survival chances at or near where you live, or plan and prepare toevacuate.

Spontaneous evacuations, in which Americans would make their own decisions without the authorities having recommended any movement, probably would occur during a worsening war crisis. Traffic jams and other complications are less likely to occur if citizens start leaving high-risk areas on their own, over a period of several hours to a few days, rather than if almost everyone, on receiving recommendations from officials, at once begins a poorly controlledevacuation. (Spontaneous evacuation by Gulf Coast residents, begun under threat of an approaching hurricane, have lessened subsequent traffic problems in the evacuations ordered or recommended by officials several hours later.)

Except in areas where the local civil defense war-crisis evacuation plans are well developed, most Americans living farther than 10 miles from the nearest probable separate target probably can best improve their chances of surviving a nuclear attack by preparing to remain at or near their homes and there to make or improve good shelters. Exceptions include those living in the vicinity of targets of great military importance to the Soviets - especially our missile fields, on which many warheads would be surface or near-surface bursted, producing extremely heavy fallout for up to 150 miles downwind. Americans living in these greatly endangered areas would do well to make their plans in keeping with the local official civil defense evacuation plans, at least regarding directions and distances to localities not likely to be endangered by heavy fallout.

Nuclear submarine ports, Strategic Air Command bases, and Air Force installations with long runways also would be destroyed by even a limited Soviet counterforce or disarming attack. These prime strategic assets are likely to be blasted by Submarine Launched Ballistic Missiles (SLBMs) in the first 15 or 20 minutes of the war. SLBM warheads are not as accurate as ICBM warheads, and air bursts can destroy bombers and submarines in port over about twice as large areas as if these same weapons are exploded at or near the surface. Therefore, SLBM warheads probably would be air bursted on these prime "soft" targets, with little or no local fallout. (In an all-out Soviet attack, hours later long runways are likely to be cratered by accurate ICBM warheads and by bombs, to make sure our returning bombers couldnot use them.)

On the following page are listed considerations, favorable and unfavorable, to evacuation. These comparative lists may help you and your family make a more logical decision regardingevacuation:

Evacuation Factors Table:

Instructions for building expedient fallout and blast shelters and for making expedient life-support equipment are given in following chapters. The reader is advised to study all of this book carefully before making up his mind regarding basic survival action.

A good flyer, no matter how many yearshe has flown, runs through a checklist covering his plane before taking off. Similarly, a citizen preparing under crisis pressures to do something he has never done before evacuate should use a checklist to be sure that he takes with him the most useful of his available possessions.

A family planning to use an expedient shelter or basement at or near home also should use the Evacuation Checklist on the following page to make sure needed survival items are not overlooked.

The family of six pictured in Fig. 4.3 used the Evacuation Checklist given below to select the most useful things that could be carried in and on their small car. They assembled categories of items in separate piles, then selected some items to take with them from each pile. They were able to leave their home 76 minutes after receiving the Evacuation Checklist. (Following chapters of this book include descriptions of this family's success in evacuating, building a Pole-Covered Trench Shelter, and living in it continuously for 77 hours.)

(Includes items for building or improving shelters)

Loading Procedure: Make separate piles for each category (except categories 1 and 5). Then load the car with some items from each category, taking as much as can be safely carried and being careful to leave room for all passengers.

The small car shown in Fig. 4.3 was skillfully loaded for a safe evacuation trip. To make room for supplies, the back seat was left at home. The load on top of the car included blankets, a small rug, and a small tent all made of springy materials which kept the load from becoming compacted and working loose under the 1/4-inch nylon ropes tightened around it. The two loopended ropes went over the load and around the top of the car, passing over the tops of the closed doors.

Hazards of evacuation would include highways blocked by wrecks and stalledvehicles. If leadership and know-how were provided, the muscle power of people usually could quickly clear a highway. Duringa major Chinese evacuation before advancing Japanese armies in World War II. I observed Chinese, using only muscle power, quickly clear a mountain road of wrecks and other obstructions. Americans can do the same, if someone convinces them that they can do it, as proved by a wintertime episode on Monarch Passover the Continental Divide in Colorado. At least 100 vehicles were held up after a large wrecking truck overturned on the icy highway. The patrolmen were doing nothing until I told them how the Chinese handledsuch a situation. The patrolmen then called forvolunteers from among the delayed motorists tolift the overturned truck back onto its wheels. In less than 15 minutes, about50 people had combined their muscle power and opened Monarch Pass to traffic.

Citizens should take direct action to keep traffic moving during a crisis evacuation.

Millions of Americans have homes within very large urban-industrial areas, probably not all of which would be subjected to blast and fire dangers. Many, whose homes are in the suburbs or adjacent towns in these metropolitan areas, could logically decide not to evacuate, but to build earth-covered shelters at or very near their homes and to supply them with life-support essentials.

Likewise, people living even as close as 5 miles from an isolated probable target may decide to build a good shelter near their supplies, rather than to evacuate. This is a good idea, provided that (1) their homes are far enough away from probable aiming points to make such shelters practical, and (2) enough time, space, tools, materials, and supplies are available.

The photo (Fig. 4.4) shows a family with no adult male that built an expedient shelter that would give far better fallout, blast, and fire protection than almost any home. They succeeded, despite the necessity of working on cold November days with snow flurries. The top two inches of earth were frozen and the next two feet so dry that most of it had to be loosened with their dull pick. No member of this family had done any serious digging before, yet they built a shelter that would have given about 100 times as much protection against fallout radiation as would a typical small frame house and at least 25 times as much as a typical home basement.

(Fallout shelters are designed for protection against radiation from fallout particles. Although fallout shelters lack blast doors and other means for keeping out blast, the better types would prevent their occupants from being killed by blast effects in extensive areas where people in houses would have little chance of surviving. In this book, an "expedient shelter" generally means an expedient fallout shelter.)

Even as simple an earth-covered fallout shelter as this Door-Covered Trench Shelter, if built well separated from flammable buildings, usually would save its occupants' lives in extensive areas devastated by blast and/or fire. The area of probable survival in a good earth covered fallout shelter would extend from where blast damage would be light but fires likely to be numerous, inward toward GZ to where most homes would be collapsed by blast and/or destroyed by fire. This ring-shaped area of probable survival from blast and/or fire effects of a 1-MT air burst would extend from about 8 miles from GZ inward to approximately 5.5 miles. Its area would be about 105 square miles, more than the 95 square miles in the circular area with a radius of 5.5 miles centered on GZ and within which this simple a shelter probably would be collapsed by the blast overpressure of a 1-MT air burst. (Door-Covered Trench Shelters and most of the other types of earth-covered expedient shelters described in this book have been proven dependable in test explosions conducted by the Defense Nuclear Agency.)

In many areas, this and even better types of expedient fallout shelters affording considerable blast protection could be built by untrained families, following the written, field-tested instructions in this book. Furthermore (as shown in Appendix D, Expedient Blast Shelters) within a few days a small but significant fraction of the population could build expedient blast shelters complete with expedient blast doors and providing at least 15-psi blast protection.

Copyright 1999 Nuclear War Survival Skills