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General Science => General Science => Topic started by: DöubleHelix on 31/05/2012 00:55:50

Title: How can radiation exposure be reduced in a post-apopalyptic situation?
Post by: DöubleHelix on 31/05/2012 00:55:50
This is my first post on this forum, and I don't really know my way around the place yet. I'm hoping I can learn more about science here (nerd warning), and also get answers to a lot of my questions. I'm a writer (not a published author, but I'm hoping that will change). I write primarily (99%) science fiction, and I want to be completely scientifically accurate. I'll start out with a question I have for a book I'm currently working on. Maybe you guys can help me out! Here's my question:

So I'm writing a semi-post-apocalyptic book. It takes place in a city where, 30 years in the past, nuclear (and most other types of) war broke out, and it basically made the place very barren. It killed off a lot of plants, animals, and people. What I want to know is how, 30 years later, people would find ways to survive the radiation. The book takes place in the ruins of the city, and radiation levels go up and down depending on where you are. Some areas are more dangerous than others. Also, assuming the blasts wiped out the majority of plant and animal life, how much of it would have come back in 30 years? Writing the book, I've often had scenes of Chernobyl in mind but scientifically, I'm not sure how to relate it to my own book.

To escape the radiation, could people take precautions such as wearing thick clothing? And what kind? Would building houses with walls and ceilings of metal be a sufficient barrier? What about showers? I've heard that you can "wash" some, but not all, radiation off. Would this make clothes dangerous after being worn several times outside?

What about significant excersize outside? What would be the limit? And how would large doses of radiation effect the human body? I know radiation causes deformations and mutation, but what does that mean exactly, as far as day to day contact?

Also, what kind of effects would a mass extinction have on an area? The area effected by the nuclear war would've been, perhaps, half the size of Oregon. What would happen if a large percentage of the plant and animal life was wiped out? Would it destroy the soil?

Sorry, that's a lot of questions! I'd appreciate if anyone could answer some of them for me. Thanks!

NERD FEST
Title: Re: Ways of Evading Radiation
Post by: CliffordK on 31/05/2012 06:15:06
I'm not sure about the cities.

If I was out in the country, I'd carefully scrape off the top few inches of topsoil and bury it somewhere.  Any chance there would be access to an abandoned open pit coal mine?  One might have to repeat the process a few times as dust would blow in from afar.

Imagine trains of pan scrapers going out to scrape off the "nutrient rich" topsoil and dumping into an abandoned coal mine.  Slowly converting the deep pit into a growing rounded hill.

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One might also choose a fast growing crop, perhaps corn that would grow fast, sucking a lot of nutrients from the soil, then mow it down and bury the plants as they could be too toxic to consume (perhaps harvesting the seeds to plant again and repeat the process year after year, to slowly leach the radioactive minerals (as well as the nutrients) out of the soil.

Or, if the soil is reasonably clean, rather than mulching, one would harvest the grains, then cut and dispose of the rest of the plants.  Doing so, however, one would have to have a source of fresh, clean fertilizer.  Most of our nitrogens come from the air.  Other minerals are mined, or made from coal ash (which may decrease in supply post-war).  Ash from trees on the surface would be problematic, but perhaps one could take old-growth trees.  Carefully peel off and separate the sap-wood and bark.  The pre-war wood could be burt to produce fertilizer.  The "new" wood could be used for heating or energy, but the ash would be radioactive.  One may, however, choose to bury it to prevent it from being spewed into the atmosphere.

Washing should help, but certainly if you got tritium into the water supply, then it would be part of the water.  Uranium will dissolve to some extent in water too. 

Presumably there would be two different dangers.  Gamma radiation from the ground and buildings, as well as DUST, and airborne particulates.  And, also water contamination.

I could imagine people wearing lead suits of armor such as the old fashioned knights armor, but fashioned entirely of lead, and very very heavy, and somewhat bendable, so one may choose lead plated steel.  And, add a Darth Vader Respirator. 

While one may think of batteries for power, they would have to be rebuilt, otherwise they would eventually die.  However, if there is a big market for lead, and pre-war lead, then there would be a huge market for old car batteries, as well as things like wheel weights, fishing weights, and etc.

Here is a list of "halving-thicknesses" (http://en.wikipedia.org/wiki/Radiation_protection#Shielding_design).  Concrete, dirt, whatever will all block radiation.  So, 6 cm of concrete is equivalent to 1 cm of lead, or about 60 cm of concrete is equivalent to 10 cm of lead.  One could imagine using very heavy, thick construction.

Many people might choose to excavate out underground dwellings.  However, if one had a clean source of dirt and concrete, then one could also fashion thick walled concrete, brick, or even dirt filled construction.  Sealing the building might be critical so that all air would come through a special filtration system.  Or...  I could imagine that some buildings would be well sealed, and have an algae greenhouse and internal air recirculation system.

Non contaminated water could be a big issue.  Perhaps all river and lake water would eventually be contaminated.  Well water might be somewhat protected, but over the decades the plume of radioactive materials might enter the wells.  So, then there may be an effort to dig deeper and deeper wells.  At some point, the deep water tables become a briny water which is not fit for consumption, but, perhaps it would be easier to punch down a super-deep well, and purify the briny water, rather than purifying the surface water.  Even agriculture might have huge problems with water sources.
Title: Re: Ways of Evading Radiation
Post by: David Cooper on 31/05/2012 19:35:24
30 years on, the place would have 30-year-old trees in it and plenty of birds. There might still be rotting tree trunks lying about pointing away from the blast that felled them. Birds and animals might die early due to cancers, but they'll continue to exist and appear to do well. I don't know if it's harder for longer-lived animals which have to survive much longer before breeding. For people, drinking water could be purified by evaporation with the help of sunshine, though I don't know if it's safe to drink nothing but distilled water. For food, if you don't want people to be dying of cancer left, right and centre, you're either going to have to rely on stores of tinned food or bring in clean food from elsewhere, unless you can grow food under glass using uncontaminated soil and maybe running the water supply through a reed bed (which might be another way of making it drinkable).
Title: Re: Ways of Evading Radiation
Post by: DöubleHelix on 01/06/2012 00:25:19
Wow. Thanks so much for all the help! The answers have been really helpful.  ;D

Now, this is science fiction, and the great thing about that is I can bend the rules as I need to! My idea was that everybody would be living in these airtight houses, some underground, some made out of old building ruins. They would contain radiation shower zones, two seperate doors, metal walls and ventilation systems.

The thing about the ruins is that the people living there are outcasts. They have some reason not to live with normal society. The book is about robots and cyborgs, and in that society, any electronic being is hated. So a lot of the inhabitants of the ruins are either robots, or robotocists, or cyborgs. Another question I had was would the radiation have an effect on robots and cyborgs? I saw another post on the forum related to this subject and it seems the whole radiation thing isn't going to be a huge problem.

It being science fiction, and in the future, I thought that there could be this special anti-radiation fabric. Like the fabric is so strong and tightly wound, it's able to keep radiation out. But it would be expensive and hard to get, so only some could use it. How long would it be, do you think, before exposure to the radiation outside would begin to have effects, for someone who went outside every other day or so?

I have high hopes for this book, thanks again for all the help! :)
Title: Re: Ways of Evading Radiation
Post by: CliffordK on 01/06/2012 01:45:48
For airborne partiiculates, you can't beat a Level A Hazmat Suit with SCBA (or supplied air) (self contained breathing apparatus)

(https://www.thenakedscientists.com/forum/proxy.php?request=http%3A%2F%2Fupload.wikimedia.org%2Fwikipedia%2Fcommons%2Fthumb%2F3%2F39%2FMHE_-_KBH_Brandvaesen_-_HAZMAT_3a.jpg%2F321px-MHE_-_KBH_Brandvaesen_-_HAZMAT_3a.jpg&hash=34b189cc4b656dd04ae5426fa16c7948)

However, it would do little to protect from high dose gamma radiation which you might choose something lead lined.  I believe there have been some experiments with lighter weight fabrics too.

If you read about WWII, essentially everything on the surface of the Earth is contaminated with radiation from the atomic bombs, bomb tests, and atomic energy leaks since the 1940's.

Some of the lowest radiation materials can be carved out of Battleship Steel fabricated prior to 1940.  A similar thing might apply to post apocalyptic periods.  Anything produced prior to the apocalypse, and is kept dry with no air/water circulation would remain relatively radiation free in the middle.  So, perhaps the central core of bombed out skyscrapers could be scraped down, revealing low radiation concrete inside.
Title: Re: How can radiation exposure be reduced in a post-apopalyptic situation?
Post by: evan_au on 01/06/2012 12:36:44
Hiroshima and Nagasaki in Japan are the only cities which have suffered an atomic explosion. Both cities were resettled and rebuilt.
Most of the people who died from the explosion were present in the city when the explosion happened. See http://en.wikipedia.org/wiki/Atomic_bombings_of_Hiroshima_and_Nagasaki
The best immediate protection after a release of radiation is to take tablets of potassium iodide, to prevent radioactive iodine-131 causing thyroid cancer. This is only important for a few weeks (half-life is 8 days).
There are longer-term radioactive elements like cesium-137 have a half-life of 30 years, and is taken up in bones, perhaps leading to a long-term increase in leukemia and cancers. 
Title: Re: How can radiation exposure be reduced in a post-apopalyptic situation?
Post by: CliffordK on 03/06/2012 06:00:53
A while ago I asked what would happen if 99.9% of the population was wiped out.

http://www.thenakedscientists.com/forum/index.php?topic=42744.0

I was thinking about something like a really bad virus.  But, one of many calamities could befall humanity.  Virus, Nuclear War, Large Asteroid Impact, etc. 

The advantage of 99.9% of the population being wiped out by a virus rather than nuclear war is that the infrastructure would remain.  However, there still would be a struggle to support it.

The world could go in two different directions.  One direction would be Mad Max like anarchy. 

The other direction would be to spontaneously reform a type of government structure, and have the remaining people attempt to preserve and rebuild society, agriculture, trade, industry.

Anyway, you might find the comments interesting.
Title: Re: How can radiation exposure be reduced in a post-apopalyptic situation?
Post by: syhprum on 01/01/2020 20:32:16
Clifford K
Sad to say I believe religion would raise its ugly head and the few survivors would soon form waring groups rather like the " Lord of the Flies",
Title: Re: How can radiation exposure be reduced in a post-apopalyptic situation?
Post by: evan_au on 02/01/2020 03:50:20
Another real location is Chernobyl, site of a rather bad nuclear reactor fire in 1986.
- The nearby city was evacuated
- A few older residents refused to leave, and are still living there.

Now, 34 years later, trees are growing and wildlife has returned to what was a city.
- Visitors are allowed to take a 1-day tour of the city

For children growing up in this environment, you could expect an increase in cancers, and a reduction of lifespan.
- And an increased level of mutations
- That means fewer older people, but probably more younger children