For that long and "bloody-minded" an eradication effort, in so small an area (100m long, 30m deep) - it seems like it'd have been far quicker and cheaper to (say) saturate the ground with liquid nitrogen. (Assuming that the termites would all either freeze, or die for lack of oxygen.)
back
4 comments
That sounds quite convincing until you actually try to do it 8) Liquid N is bloody cold until it hits the environment (for want of a better word). Initially I thought of going in with boiling water but that suffers from the same problem - that there bloody equilibrium thingie.
I'd also look into something like liquid grout. You use that (I'm a Civ Eng grad, IT company owner) to stabilize ground. That depends a lot on the rock involved. North Devon and sandy soil mentioned so it will be tricky.
I think it could have been done quicker but you have to bear in mind that people's houses are on top and the council's and other groups would have worried about that and a lot of other factors.
Neither the LN nor the boiling water would need to literally saturate the soil. Nor reach thermal equilibrium (-196C for LN, 100C for boiling water.) So long as conditions (temperature, O2 availability, etc.) in every cc of the targeted volume were nicely beyond what any termite could survive, that'd be enough.
LN would plausibly 1) create a long-lived hypoxic zone, and 2) have minimal effects on the groundwater, so I hand-waved that idea. Your boiling water would probably work through the "mud" they might use to line tunnels and their nest far quicker.
It's just as well you and I were not appointed to deal with this. It could have got ugly.
Let's start off with demolishing the houses with a controlled explosion that just implodes the structures so that we don't fire termites off into the blue. Carefully distribute the house remains to the perimeter. All crossings of the perimeter will involve a thorough decontamination.
Now we drill two metre (6'ish) deep holes every two metres with a diameter of at least 32mm (1.25"). Then we treat the problem:
Find the perimeter of infestation (may have to destroy more properties). Create a 3m (10') deep trench, 30cm (12") wide along the entire perimeter. Fill the trench with standard 1-2-3 conc. Make sure it is vibrated properly and use a viscosity admix. to ensure the trench is properly filled.
We'll need some heavy lift helis eg Chinooks - several are available from the Army and RAF or perhaps EH101 based jobbies - Army. We'll also need some containers and I think a 8 cu yard skip ie a standard builder's skip will do nicely. Yes we do have a wacky approach to units here in the UK. Fill the skips with boiling water and use the helis to drop the water on the area from above. Consider salting the water to lower the boiling point and make it more toxic in an environmentally responsible way.
Finally we go in with a fleet of ready mix lorries with pumps and long hoses. We pump a cementitious slurry into the holes and then finish with a capping slab of conc as required to support subsequent structures.
I'm actually half Devonian (mum born in Dartmouth) and I studied Civ Eng in Plymouth. I now live next door in Somerset.
I suspect they know more about it than you. This worked. For the first time in history.
I was thinking hydrogen peroxide, since it seeps into the ground just like water and decays into water. Also I imagine it's much cheaper than liquid nitrogen.
That could be cool on a small scale. But H2O2 decays into H2O and oxygen, and is a very reactive oxidizer. With organic matter in the soil, it will produce all sorts of interesting chemicals. Those will end up in the groundwater.
(Or, just look at the fire diamond for H2O2. Proposing to bring tons of that stuff into a residential area would not be popular.)
I facetiously recommended a tactical thermonuclear explosive in a comment below, but on a more serious note, this was an issue of national security and surely they should have just used eminent domain to oust these people from their homes and then used some radical scorched earth solution as you suggest to just destroy this menace without prejudice. The British government is normally very judicious with eminent domain and will destroy your home if it is causing an unpleasant wind diversion for some species of rare seagull.
"The British government is normally very judicious with eminent domain and will destroy your home if it is causing an unpleasant wind diversion for some species of rare seagull."
Oh no they won't! Could you provide some more details please.
One recalls the recent story where an impostor sold a man's house without his consent and the British government was just "sorry, we signed the papers, it belongs to him now"
That's bad, but nothing to do with eminent domain.
The UK govt doesn't generally get involved in house sales. That sounds like a tale of good old fashioned fraud and I think I know the one you are on about - https://www.bbc.co.uk/news/uk-england-essex-59069662
The Police response looks a bit shit to start with but nothing to do with the government - Welsh or British.
If you are going to have a go at this sort of nonsense then you need to sound credible. You are not going to bring down civilisation as we know it with a comment like that.
Destroying the homes was out of the question as the article states, the danger of spreading even a couple of reproduce-capable termites was too high.
I didn't understand that part. Sure, a conventional demolition, where debris is carted off to the landfill wouldn't work in this case. But surely onsite burning would do the trick?
Termites can dig very deep. The final inspection went 30 meters down. Burning down 30m into the earth would require something far beyond what "onsite burning" usually involves. (Hence the "small subterranean fusion bomb" comment from kingcharles.)
It wouldn't remove the termites, but it would remove the surface structure ... which should make it easier to do the subterranean work. Instead they wouldn't let the homeowners modify the house.
Isn't that 30 meters one of the dimensions of the surface area that was inspected?
If they actually inspected 30m into the Earth, they'd have plenty of opportunity to kill everything in the way as they did it.
I sometimes have very weird and destructive thoughts, but I have often wondered if it were possible to take thermite and pack it, make it stable and rigid somehow, enough that it could be made into a long rod, like rebar, suitable for pounding into the earth. Then you surround your nest or whatever with a bunch of rods, run one through the middle, set them alight and let them just burn down however many yards.
Thirty meters, though ... whew.
Outside of sci-fi and some very arid environments, rapid extreme heating of large quantities of soil will produce big steam explosions. Which might spread some relatively unheated, termite-laden clods of earth over a wide area.
In a different context (limited quantities of soil with extremely heavy chemical contamination), I have seen serious proposals to drive heavy electrodes deep into the soil, gradually apply very large currents (avoiding steam explosions), and let the heat & electricity destroy the contaminants in-place.
What about pressure? Would it be possible to apply either a violent pressure wave, or some sort of compaction technology to basically crush everything 30m down?
How about microwaves? If the soil is moist, perhaps microwaving the area could sterilize it thermally. Slower rate of heating should prevent explosions.
Drilling and filling would probably work better.
I guess by the time you got enough thermite in the ground it wouldn't be very efficient.
That would just remove the food-source. Removing the food source for a colony that you would rather have stay-put seems like it would be counterproductive.