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One Man’s Preparedness Journey

Watch this story about Peter Larson (a good friend to TACDA board members) on National Geographic’s TV show “Doomday Preppers”.

Peter Larson is a recognized expert in the field of Prepping. His unique brand of planning, training and preparing helps Peter stand out as a voice of reason amongst conspiracy theorists, renegades, anarchists and all around crazies.

Kennedy on Civil Defense

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The following is a letter from President John F. Kennedy to the members of Congress and read by Stewart Pittman

October 6, 1961

Gentlemen:

I was gratified to learn of the productive meeting of the Committee on Civil Defense of the Governors’ Conference on September 17 in the Pentagon. The basis was well laid for continuing and close cooperation between your committee and all of us concerned with the federal civil defense program.

There is need for a nationwide understanding of what each level of government, each private organization and each citizen can do to bring about and maintain the best attainable protection for the civilian population against the major effects of a thermonuclear attack. Information is in preparation which I will use to inform the American people on what individuals should know and can do for their own protection. In the meantime, your committee may wish to inform the Governors of the goal towards which the Federal Government, the state governments, industry and other institutions in the United States should work.

In simple terms, this goal is to reach for fallout protection for every American as rapidly as possible. Radioactive fallout, extending down-wind for as much as several hundred miles, could account for the major part of the casualties which might result from a thermonuclear attack on an unprotected population. Protection against this threat is within reach of an informed America willing to face the facts and act.

The Federal Government is moving forward to bring into operation fallout shelter space for large groups of people under very austere conditions. Many homeowners, communities and business firms can and will provide more adequate and better located shelter space for their own needs. The Federal Government is backing this effort with a massive dissemination of technical information. In addition, we will inform those who cannot afford costly structures on low-cost methods of improvising shielding against fallout radiation. The people of this country will be urged, by me, by the Governors and by other leaders to do what is within their means.

The state governments have a vital role to play in accelerating attainment of the goal of full fallout protection. Shelter can be provided in new construction of state and local public buildings. State and municipal laws and ordinances can be adapted to encourage private initiative in this effort. State and local leadership in organizing people to prepare, and communities to operate, during and immediately after an attack is a cornerstone of any successful civil defense effort.

I look forward to the closest cooperation between all levels of government in the United States to move rapidly towards this goal. Your committee is making a major contribution in stimulating participation by the state governments in the nationwide civil defense effort.

Sincerely,

JOHN F. KENNEDY

A safe-room tip!

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Hi.  James here.  I have a question for you:

I am in the beginning process of building a barn with a small 16 x 12 safe room in the basement.  The walls will be poured concrete, 12” thick and I faced with 9” of stone.  The ceiling is an 8” slab.  I was opening that you could help me with the door and NBC system, as well as suggest what steps need to be taken to ensure I have properly planned for both the installations.  Can you help me with this situation?

 

Hi James,

Sounds like a neat project!   If you site your safe room in the corner away from the outside wall and next to solid earth (all the way to the top) the walls will likely be OK.  My concern is the thickness of the ceiling.  In Switzerland, bomb shelters are Federal building code…..everybody must have them.  There are one million surplus shelter spaces there, and they are still building 500 shelters each month.   Swiss shelter code is very explicit and well engineered for fallout protection and blast to three atmospheres (45 psi overpressure).  Their ceilings are anywhere from 30 inches to a meter thick, heavily reinforced with lots of rebar.  Depends on what other structure will be built on top, or how much additional earth will be added on top.  Most communal shelters feature a meter of concrete and a meter of earth.  I have lots of video we shot in Switzerland that show this. We also have the Swiss building code on a PDF that you can purchase from TACDA.

Vertical, walk in type doors let in a great deal of radiation.  The Swiss use armored doors, which feature an eight -inch thick concrete door leaf.  This door must be cast into the wall- retrofits are possible, but difficult.

Your emergency escape tunnel hatch should be made of solid steel and sit horizontally on the ground.  DO NOT compromise your ceiling thickness with a hatch…..run a tunnel out twelve feet or so, and then go vertical for the hatch.

The Swiss concrete shelters with 36 inches of concrete in the ceiling (though good for fallout and blast) WILL NOT defeat initial radiation, which is present within 7500 feet of a nuclear detonation).  At 3 atmospheres (45 psi), initial radiation could be a problem.  But those Swiss shelters that have a meter of concrete over them, plus a meter of earth, will fare well.

An eight-inch concrete ceiling will provide a protection factor (PF) of only around ten.  This will reduce your exposure to outside fallout type (gamma) radiation by only a factor of 11.  My personal minimum is PF-250, which will require a 24 inch ceiling and/or wall between you and the radiation source. If the earth-side wall is completely below grade, then that wall only has to be ten inches thick.   You can play around with the formula by using 2.7 inches of concrete for a halving thickness.  Each 2.7 inches doubles the protection factor.  Ten halving thicknesses provide a PF of 1,000.  That’s 27 inches.  PF1000 makes for a nice shelter that will provide a margin of safety if you get a rainout….that is, all the fallout that was jettisoned into the air by a local ground burst is scavenged from the atmosphere and returned to the ground instead of drifting hundreds of miles downwind. This can raise your exposure level outside the shelter from 1000 rads/hour to as high as 10,000 rads/hour.  A PF250 shelter will probably not be enough in this scenario.

Best regards,

Paul Seyfried

President of Utah Shelter Systems – www.utahsheltersystems.com 

History of the 1960s Fallout Shelter Program

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In response to an inquiry by Michael McFall, reporter for The Salt Lake Tribune

By Paul Seyfried

The National Facility Survey, done in the 1960s, reveals a valuable history of fallout shelters. President Kennedy was a strong advocate of a national shelter program, much like Switzerland’s shelter program is today. His shelter program was modeled after the Swiss system. He had planned to unveil the program during his trip to Dallas. He was distracted by a murder’s bullet. Lyndon B. Johnson cancelled our civil defense shelter program, which would have built blast-hardened shelters in the nation’s densely populated cities. Less rigorous fallout shelters would have been constructed for rural areas.

Later, an effort was made by the U.S. Government to survey large buildings with multiple stories employing masonry construction to find areas in them that would provide a minimum level of protection that would give occupants a fighting chance of surviving the fallout effects from a nuclear attack. A national grain reserve was established in rural areas that would provide enough food to feed the population for seven years (80 percent of grain is fed to meat-producing animals in peace time, but most of these would be slaughtered immediately, retaining only breading stock to replenish herds during recovery). This frees up millions of tons of grain for human use. We no longer maintain such a reserve, while Russia still maintains a four year supply. We are now on a Just-In-Time system.

The established protection criteria was a protection factor of 40 (or PF 40). Formulas for determining this level were devised, and survey teams went out and identified hospitals, municipal buildings, high rises, etc. that had the right features. The idea was to house as many Americans as possible in hastily organized shelters, stocking them with water, crude rations, and chemical toilets.

The critical need for shelter occurs in the first two to three days, assuming the attack commencement and conclusion occurs within a few hours. In the early years of the 1960s, most weapons would be delivered via aircraft…so we had maybe 14 to 20 hours of preparations before an attack would arrive. Evacuation plans were developed to move as many people outside of large cities. Counterforce weapons and strategies were not developed yet, so cities were assumed to be the primary targets, other than obvious enemy airfields.

The age of the ICBM changed all of that. Americans today would have no warning….the concept of a suit on TV telling Americans that an attack was imminent is fantasy. Flight time of a submarine-launched ballistic missile, fired from 200 miles off-shore at Washington DC, programmed for a depressed flight trajectory, would arrive on target in about 3 1/2 minutes. It is highly unlikely that the U.S. could detect the launch, plot its intended target, pick up the phones and warn the White House Situation Room, and get the POTUS to the bunker entrance in time. The National Command Authority would likely be wiped out, with any surviving members, unable to determine who was in charge (communications would be vastly suppressed from the concurrent EMP laydown) before most of the U.S. nuclear deterrent was reduced to smoking rubble.

[Russia will have 80 percent of it’s strategic nuclear missile force on road and rail-mobile launch vehicles by 2015. It’s remaining fixed silos are “cold-launch” systems, able to be re-loaded in a few hours with fresh missiles. SS-18 silos are “super-hardened”, and are difficult to neutralize. Arms treaties do not address “reloads”…only launch silos. Meanwhile, our land-based nuclear deterrent is the old Minute Man system, initially deployed in 1965. They are still in their original silos, addresses unchanged. We can tell from the laydown splashes of Russian missile tests off the Kamchatka peninsula, which missile field they are rehearsing on. But I digress.]

The old fallout shelters had NO ventilation systems, no sanitation systems, other than the 15 gallon steel drum toilet kits stocked there. No blast doors, or blast valves on ventilation pipes to protect occupants from direct weapons effects (heat, blast, debris, fire). This joke of a system gave ammunition to the anti-civil defense lobby. Indeed, these “shelters” were a joke. A PF 40 is BARELY adequate protection, assuming your area was not heavily hit by fallout. Virtually everyone inside would probably get sick…but most would not die.

Of course, the president and other officials were to be housed in hardened bunkers, designed for high overpressures. We know how to protect people from WMD, we just don’t do it for the taxpayer. Switzerland, Sweden, Norway, Finland, Singapore, Yugoslavia, Czech Republic, South Korea, Russia, China, Israel, and lately, Qatar, Saudi Arabia, UAE, and others have initiated shelter programs to some degree or other. Switzerland remains the only country where 120 percent of the entire population, not just government officials, have blast-hardened, nuclear, biological, chemical shelters. They are required by Federal building codes for any area intended for human habitation. Homes, hospitals, schools, churches and temples, apartment buildings, stores, shops, manufacturing facilities, theaters, etc…..they all have them under the building, or a separate one nearby. I toured many of them in 1999, taking lots of pics and video. Everywhere we went, we’d ask to see their shelters. After an odd look, we’d explain that we were Americans and that we didn’t have any shelters in our country….and we would like to see theirs. All showed them upon request.

At a school in a small village, we found the school shelter under a field house and track. So happens, they were conducting their semi-annual war game drills, and cleaning/maintenance routine. Pharmaceuticals  were replaced with new ones, the six month old inventory was rotated to retail stores. Diesel fuel for the generators were tested. Kitchens exercised. A clean-cut male teenager asked us in perfect English is we’d like to go inside. Of course, we said “Yes!” A few minutes later, he returned with a seasoned man, white hair, in a pale blue uniform. He was the officer in charge of that shelter. He graciously gave us an hour and a half tour, through the infirmary, medical bays containing 36 patient beds each, and general housing areas for healthy citizens (bed capacity: 250, personnel capacity: 750).

They hot bunk…just like the navy. You get a bunk for every three people. Each had a pillow, exactly placed, as with a ruler. Fresh water reservoir, flush toilets, showers for hygiene and decontamination. Ten kilowatt diesel generator in a separate area, sealed off with a concrete blast door. NBC filtration units, all capable of being operated by six volunteers, on 15 minute shifts. With 750 people, they’ll have no trouble finding volunteers. Ceiling thickness, was one meter of steel reinforced concrete, and a meter of earth (the soccer field). Fallout protection factor:  Over one million. [Remember the U.S. spec? PF40?] Most residential shelters had protection factors of around PF5,000.

Switzerland’s tax burden to the citizen to maintain their civil defense program is about $60.00 per year per person. That’s a real defense program. Actually defending/protecting the intended victims in the next war. It is not based on the threat of annihilation. DoD is hostile to an American program.  It competes with funds for pet weapons programs. In Russia, Civil Defense has a general sitting at the table with the other branches of the armed forces. It is well funded…..Russia is now building more shelters again. Construction of the Yamantau Mountain facility never ceased. http://en.wikipedia.org/wiki/Mount_Yamantau

In WWII Germany, there was not a single fatality inside government-built “bombproof”, shelters constructed featuring four foot thick walls and ceilings. Germany has a high water table in many areas, so they build bombproofs up to four stories high. Many were struck with direct hits from 500 lb and 1,000 lb bombs, yet no one inside suffered injury. I doubt that an American city hall building would fare so well. In the Hamburg firestorm raid, 45,000 civilians perished in the fires…mostly exposed in the streets, trapped in hasty basement shelters, or crude trench shelters. None of the 240,000 inhabitants that were sheltered inside bombproofs were injured. Indeed, some had to step in the puddles of melted fat left from people who arrived at the shelters too late when they emerged the next morning.

The old fallout shelters were cleaned out during the Carter Administration, the biscuits fed to the hogs in Nebraska. Some survive with collectors, and biscuits were tested at Brigham Young University and found to still be viable. I have a CD chemical toilet, mostly for memorabilia. We have modern chemical toilets in our shelters. The Clinton Administration destroyed $200 million worth of the Victoreen fallout meters that still remained in the hands of state authorities. We rescued about 1,000 of them from Arizona. Many still work. I would agree that a shelter stay in the old public fallout shelters would be a real trial. The protection value was not very good, and conditions inside would be awful. But the German shelters were occupied at six times their rated capacity….occupants were packed inside like Japanese commuter trains. They slept all night standing up….one couldn’t fall down. Air was very bad, despite ventilation systems…they were overcrowded. But they lived another day.

As we now have a nuclear stockpile that the DOE refuses to certify as safe and reliable, and being that we can no longer manufacture new warheads to replace the long-obsolete (expired) warheads, I wonder how long we will continue to ignore the growing nuclear threat from abroad. Putin is building several new classes of nuclear subs, and new road-mobile, hard target capable ICBMs…..like this one. (http://www.globalsecurity.org/wmd/world/russia/rs-24.htm) The older, hard target killers like the SS-18 are getting upgrades to keep them in service for another decade, oddly, by the Ukrainians that manufactured them. Though and old liquid-fueled rocket, the SS-18 has never experienced a launch failure. A far better record than the Minuteman or Titan.

In our current state of vulnerability, it is important to realize that if the worst should happen, we are all on our own. No help is coming, no one is going to rope down from an orange Coast Guard chopper to save us. In the end, you are either ready, or you are not.

Fallout Shelters

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TACDA received the following email from a concerned citizen:

Hello,

Due to heightened world tensions I recently contacted Emergency Services here in Lane County Oregon to see if we had any public fallout shelters near my town of Florence. I was surprised to discover the public shelter program no longer exists. They didn’t even know if there were any suitable buildings that could be used in a pinch. Having been raised in the 60’s I remember those yellow shelter signs.

My question is are you aware of any members of congress or public officials who would support starting a shelter program again. So far when I have brought this up officials either don’t want to talk about it, make me feel like some kind of nut or pretend interest. My local Senator Merkly sits on the FEMA committee and I brought this up with him but interest is low. FEMA wouldn’t even answer a letter. So I’m searching for officials who might be pro shelter programs to lend support or at least get some discussion going. Any help appreciated.

Thanks,

Dave P.

Here is our response:  (written by Paul Seyfried and Sharon Packer – http://www.utahsheltersystems.com/)

Dear Dave,

We have found it to be almost impossible to find government officials who would be interested in revamping our national shelter program.  One city, Huntsville in Madison County, Alabama, under the direction of Kirk Paradise (unfortunately now deceased), revitalized its fallout shelter program in 2006.  It was an amazing effort.  I have attached a report he made for the Physicians for Civil Defense. (Kirk’s attachment will follow.) I’m not sure if they have kept this program current or not.  He served on our TACDA Board of Directors for several years before his death in May of 2012.

TACDA exists for the education and enlightenment of the public to national threats and mitigation efforts.  We are convinced that until the conversion of the general public to civil defense brings a public outcry, there will not be officials who will support the funding of such a program.   It is our hope, that folks like you will spread the civil defense message and help in the accomplishment of that goal.  Most government officials want to please their constituents, and they will only support popular efforts that will help them to retain their office.

TACDA encourages the building of private shelters, but does not (and cannot) recommend one company over another.  Sheltering in place appears to be the most practical option.  A  fallout shelter can quite easily be incorporated into a basement room.  Stand alone underground shelters, however, would be required for full NBC protection (fallout, blast, thermal chemcal/biological and EMP effects).   Public shelters in the U.S. were basically fallout shelters, only, with minimal blast protection.  The U.S. never did advocate shelters built to the Swiss standard.

President Kennedy was a strong advocate of a national shelter program, much like Switzerland’s shelter program is today. His shelter program was modeled after the Swiss system.  He had planned to unveil the program during his trip to Dallas.  He was distracted by a murder’s bullet.  LBJ cancelled our civil defense shelter program, which would have built blast-hardened shelters in the nation’s densely populated cities.  Less rigorous fallout shelters would have been constructed for rural areas.  Later, an effort was made by the U.S. Government to survey large buildings with multiple stories employing masonry construction to find areas in them that would provide a minimum level of protection that would give occupants a fighting chance of surviving the fallout effects from a nuclear attack.  A national grain reserve was established in rural areas that would provide enough food to feed the population for seven years (80% of grain is fed to meat-producing animals in peace time, but most of these would be slaughtered immediately, retaining only breading stock to replenish herds during recovery).  This frees up millions of tons of grain for human use.  We no longer maintain such a reserve, while Russia still maintains a four-year supply.  We are now on a ‘Just-In-Time system’.

The established protection criteria was a protection factor of 40 (PF-40).  Formulas for determining this level were devised, and survey teams went out and identified hospitals, municipal buildings, high rises, etc that had the right features.  The idea was to house as many Americans as possible in hastily organized shelters, stocking them with water, crude rations, and chemical toilets.   The critical need for shelter occurs in the first two to three days, assuming the attack commencement and conclusion occurs within a few hours.  In the early years of the 1960s, most weapons would be delivered via aircraft…so we had maybe 14 to 20 hours of preparations before an attack would arrive. Evacuation plans were developed to move as many people as possible outside of large cities.  Counterforce weapons and strategies were not developed yet, so cities were assumed to be the primary targets, other than obvious enemy airfields.  The age of the ICBM changed all of that. Americans today would have no warning….the concept of a suit on TV telling Americans that an attack was imminent is fantasy.  Flight time of a submarine-launched ballistic missile, fired from 200 miles offshore at Washington DC, programmed for a depressed flight trajectory, would arrive on target in just a few minutes.   It is highly unlikely that the U.S. could detect the launch, plot its intended target, pick up the phones and warn the White House Situation Room, and get the POTUS to the bunker entrance in time. The National Command Authority would likely be wiped out, with any surviving members unable to determine who was in charge (communications would be vastly suppressed from the concurrent EMP laydown) before most of the U.S. nuclear deterrent was reduced to smoking rubble.  The power drop from an EMP would be the only warning the general public would perceive, and ‘in place’ sheltering the only chance of survival when living in close proximity{F to primary targets (targets with retaliatory capability).

[Russia will have 80% of it’s strategic nuclear missile force on road and rail-mobile launch vehicles by 2015.  Its remaining fixed silos are “cold-launch” systems, able to be re-loaded in a few hours with fresh missiles.  SS-18 silos are “super-hardened”, and are difficult to neutralize. Arms treaties do not address “reloads”…only launch silos. Meanwhile, our land-based nuclear deterrent is the old Minute Man system, initially deployed in 1965.  They are still in their original silos, addresses unchanged. We can tell from the laydown splashes of Russian missile tests off the Kamchatcka peninsula, which missile field they are rehearsing on.  But I digress.]

The old fallout shelters had NO ventilation systems, no sanitation systems, other than the 15-gallon steel drum toilet kits stocked there. No blast doors, or blast valves on ventilation pipes to protect occupants from direct weapons effects (heat, blast, debris, fire).  This joke of a system gave ammunition to the anti-civil defense lobby.  Indeed, these “shelters” were a joke.  A PF-40 is BARELY adequate protection, assuming your area was not heavily hit by fallout.  Virtually everyone inside would probably get sick…but most would not die.  Of course, the president and other officials were (and are) to be housed in hardened bunkers, designed for high over pressures.  We know how to protect people from WMD, we just don’t do it for the taxpayer.

Sharon Packer (TACDA Board Member), Paul Seyfried (TACDA Advisory Committee)

Document by Kirk Paradise, Plans Coordinator:

Huntsville in Madison County, Alabama, is revitalizing its Fallout Shelter Program. The program consists of three parts: shelters; plans and training and monitoring equipment. Huntsville-Madison County Emergency Management Agency has identified Fallout Shelters for both the general public and selected hospitals and clinics under the DHS Metropolitan Medical Response System (MMRS) program.

The program requires the 124 MMRS cities in the nation to prepare against the effects of a Radiological Dispersion Device (RDD) and a postulated 10 kiloton detonation of either an Improvised Nuclear Device or a nuclear warhead. Preparedness levels are based on population; in the case of Huntsville, it is 7,500 fatalities, 25,000 casualties and 100,000 displaced persons. The medical community can manage the fatalities and casualties but a sheltering program for displaced persons is beyond the scope of hospitals and clinics. Pacing displaced persons in Red Cross-type shelters with no or unknown radiation protection from radiation would leave them vulnerable to high level radiation exposures.

Starting in 2005, Huntsville devised and followed a two-prong solution. First, five MMRS medical facilities were identified which were judged to afford protection from radiation. At the same time, based on fallout shelter survey records kept locally on file since the 1960s and federal records which have not been updated since 1992, over 100 previously surveyed public shelters were identified for the general public. Over time, many of the previously surveyed shelters have been razed, burned or otherwise no longer exist. To counter this loss, thirty buildings in the county also judged to afford protection from radiation were identified and added to the list of the five MMRS medical facilities. Permission to survey all these facilities was sought and obtained and a Civil Engineer was contracted to perform the surveys. The engineer used FEMA formulas and procedures to calculate the “Fallout Protection Factor” in the different areas of each building. Once surveyed, the thirty public Fallout Shelters were added to the existing list; the list totals about 150 usable shelters with an aggregate capacity of about 300,000 persons. Madison County’s population is just shy of 300,000 persons. Permission has been sought from the previously surveyed buildings and about 60% have granted permission so far.

The life-savings qualities of a Fallout Shelter are useless unless people know how to use them. For this purpose, the Huntsville-Madison County Emergency Management Agency developed a Fallout Shelter Guide, a brief plan with checklists to enable a Shelter Manager to quickly select and train a Shelter Management Team to accommodate the needs of the shelter population and enable them to survive in the shelter until they are either rescued/evacuated or it is safe to emerge. Two Fallout Shelter Management Courses were developed and presented. One was for the MMRS medical facilities and was presented in August, 2006. The second was for Public Fallout Shelters. Four sessions of the 8-hour course were held in January, 2007. All MMRS medical facilities and about half the public shelters now have trained shelter staff. In addition, personnel from the Army’s Redstone Arsenal (adjoins Huntsville in Madison County) attended the training. The Arsenal and its major tenant, NASA’s Marshall Space Flight Center, each have several dozen previously surveyed Fallout Shelters with an aggregate capacity of 60,000+ persons. None of the shelters are stocked with any survival supplies or equipment other than what might happen to be there. If activated, the public will be instructed to bring essential supplies: at least one gallon of water per person; personal needs; clothing; bedding and food for an expected shelter stay of perhaps a few days up to two weeks. Purposeful leadership is essential in shelters to organize and motivate people – perhaps entering a shelter bringing nothing but a few supplies but lots of anxiety and fear – into a community capable of group survival.

To provide a radiological monitoring capacity for all the shelters, the Huntsville-Madison County Emergency Management Agency stores a supply of the Civil Defense Radiological Monitoring kits from the 1960s. These kits are still maintained and calibrated by the Alabama Emergency Management Agency. Alabama is one of a few states that has an active maintenance and calibration program for its radiological monitoring instruments. For the MMRS Medical facilities, new, specialized equipment is being procured.

The Fallout Shelter program in Huntsville, which is currently the only jurisdiction in the United States known to be revitalizing its program, will allow MMRS medical facilities to continue medial operations in a high radiation environment and provides for the protection of the general public. The MMRS medical facilities can move operations and patients/staff/families to areas that offer excellent quality protection from high level radiation. The public can go to public Fallout Shelters that will greatly reduce their exposures and where their needs can be met. With protection from radiation and purposeful leadership, people in both types of shelters would emerge as survivors, ready to be part of a national recovery and not be left as just helpless victims of a terror attack. Efforts will continue to gain permission from owners of additional shelters and to schedule more training courses in the future.

© Copyright 1991-2006 Physicians for Civil Defense. All Rights Reserved

Location, Location, Location!

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By Paul Seyfried and Sharon Packer (www.utahsheltersystems.com)

Tips to know when starting your fallout shelter …

Choose your underground (UG) site carefully.  The first attribute for a good shelter location is an area with a low water table- that is, an area where you can dig a trench 18 to 20 feet deep without hitting ground water.  In many areas, the water table can vary by seasonal rainfall (areas subject to hurricanes fall into this category).

Rocky Soil:

Rocky soil will work, but it can add time and expense to the excavation.  The soil on our remote site is very rocky.  We were taking out rocks the size of a small Volkswagen.  Never back fill with large rocks. If you have solid rock you will need to blast (which is very expensive but doable).   Gravely type soil is fine and drains well.

Wet Soil:

Wet soil of any kind, is a total non-starter. Spring excavations will show you the most likely ‘high water’ level. For installations later in the year, carefully estimate the high water level of the soil.   If you reach wet soil during excavation, back fill to a safe, dry soil level before installing the shelter. If you need more cover for warmth or radiation protection, mound the dirt to make a hill over the shelter.  In areas of potential blast or high winds, make sure the slope of the mound does not exceed 30 degrees.

Hills & Valleys:

We would suggest that you look for an area that is not at the bottom of a vast slope. When placed in these locations, over a period of hours to days, the water that has collected over a shelter will super-saturate the soil and find any imperfection in the integrity of the shelter, and come inside.  When a shelter is located up-slope, on high ground, the rain will run AWAY from the shelter and not saturate the soil deep underground (unless the soil is 100% sand).  In short, high ground is good – low ground, not good.

We have built “submarines”, where the entire shelter is below the water line, but they are welded plate shelters (steel fuel tanks), with solid steel pipe entrances.  Submarine shelters must be held in place by heavy steel straps that are anchored into concrete.  Steel plate shelters are heavy and harder to handle in the hole.  A 48” diameter entrance elbow made of corrugated pipe may weigh 250 pounds, where a 1/2 inch walled steel pipe entrance will weigh thousands of pounds.  Water problems can be dealt with, but they increase costs, and the shelter components are more difficult to assemble on the job site. Keep in mind that wet soil and clay type soils do not ‘arch’ and will compromise your blast protection.

Clay Soil:

Clay type soils hold water for a long time.  When this type of soil is saturated, your underground structure is not only holding up the weight of the soil, but also of the water it holds. Clay soils are not even recommended for use against concrete foundations, as clay creeps and moves, and will eventually crack concrete walls.

In clay excavations, water will collect in and around the disturbed areas and the clay will hold the water, forming a “swimming pool” effect. Clay soils will require a good drainage system, such as a French drain.

Always consult a good soil engineer before installing your underground shelter. When installing in clay, soil Engineers often recommend that you totally remove the clay overburden, fill with crushed rock up to about 3 feet or so of grade and then apply engineer’s fill or road base for another couple of feet before applying a top soil layer.  A layer of sediment screen over the crushed rock before the engineer’s fill goes in will protect your French drains from becoming clogged in the future.

We surveyed a shelter (not one of ours) that was buried in red clay soil in Virginia about six months ago, and it was near collapse when we looked at it.  In addition to the clay soil present, the site was located in a large bowl- about 300 acres worth- so that all the rain in the world drained down to where the shelter was installed. Location, location, location!  Parts of the shelter may possibly be saved if they remove the clay and replace it with engineer’s fill and crushed rock … something that will arch. The crushed rock will arch well, even when wet.  Clay does not arch well, even when dry.

Deformation of Shelter:

Some deformation of the end caps/bulkheads in steel shelters is completely normal and expected.  We know this will happen and we locate the bolt pattern holding the air handler brackets in a close, square pattern knowing that the strut will lift away from the end cap upon backfill. We plan for this when installing the deck (that’s why the deck does not contact the end caps) and the ventilation intake pipe. Corrugated pipe is not a particularly accurate cylinder, as it is wound in a spiral format, like a paper towel tube.  Some deviation in the diameter dimensions is very normal. Most of them seem to come out a little larger on the ends than in the middle – but not always.

We recommend using a large track hoe (size 290 to 330) instead of a backhoe.  The track hoe will get the job done much more quickly, and time is money.  It also provides a huge safety factor when digging a deep installation.  Never, ever, use a Bob Cat to back fill your shelter.

Pick your location carefully.  Don’t be in a hurry.  Dig a test hole and do a perk test.  It will more than pay for its self in the long run—and NEVER back fill with clay.