So what's the dif between using an outhouse and a composting toilet/bucket/pile as far as the composting process goes? Provided that both use sawdust as the carbon? I mean, one is in a deeper hole but there's still plenty of oxygen and worms down there.
And while we're at it, if say you were just pooping in buried holes all over a pretty big property, then how would this compare biologically with just a big pile composting? Just more spread out nutrients, or more spread out pathogens?
I haven't read the book either so anything I have to say on the subject should be taken with a grain of salt. It seems the only advantage to a composting toilet would be convenience. spreading it out all over the place is the most natural idea. pathogens are everywhere and whether of not we get sick from them is generally dose related. so on one hand having a big pile would theoretically be more likely to concentrate the pathogens and increase the likleyhood of a large "dose" (I don't want to think about how . on the other hand the heat and microorganisms generated by a proper compost pile ought to take care of the pathogens too. Quite frankly a standard toilet is a luxury I don't plan to give up. I considered it when our septic system crashed but the only people that seemed to think it didn't smell were the ones that were on the extreme eco fringe and the people that were selling them. makes me suspicous of there opinion.
My thinking is that the so called "composting toilets" are probably mis-named. I think they are more like "poop cookers." They encourage you to not pee in them. And then they use some sort of energy (sometimes solar) to dry out the poop. If the temp is hot enough, the poop will be sterilized. Then somebody has to move the poop. But at this point, it is quite safe for use as almost anything. The only concern might be what kinds of meds a person might be taking that is still in the baked poop and might not be good to introduce to your soils.
If you have standard poop (not cooked), I think minimizing the surface area is wise. And to keep it from the air and bugs as much as possible is wise. Frankly, a septic system seems optimal to me. But it is expensive and it does use a fair bit of water.
One thing I keep thinking of is hearing how peace corps folks teach folks in africa to stop pooping in the woods. Apparently flies go out, land on the poop, then come back and land on their food. And lots of people die from this.
So I like the idea of a properly managed outhouse. A big roof. Rain water is directed away from the outhouse. And people are asked to not pee there - just poop. Lots and lots and lots of sawdust is provided. With a healthy system there should be no smell (or almost no smell) and nobody should ever have to empty it. With a nearly dry system, nothing should end up in the ground water.
I like the idea of building an outhouse on skids. And then if the hole ever does fill up, you can just move the outhouse to be over a new hole. Put a nut tree seed on the old hole. If you grow the tree from seed, it will develop a fantastic tap root (transplanted trees nearly always lose their taproot). By the time the tree bears nuts, the pathogens will be long gone.
The composting toilets (at least the ones I looked into) didn't use any supplemental heat unless it is to keep the temp for composting optimal. http://oikos.com/library/compostingtoilet/ if I had a weekend getaway cabin or camphouse then I would use one, but not for everyday.
there are quite a few options out there. I found it a bit surprising. I'm sure that (As with anything) there are some well researched optimal products out there along with some cheapo ideas that haven't had much thought put into them. I think if you are considering one it would be well worth asking for references.
It's interesting, it's funny, it has drawings and photos. He answers all your questions about pathogens and everything else, even stuff you hadn't thought of asking.
And he explains why you shouldn't bury it in a hole in the ground. Or multiple holes in the ground. Do that, and you're no better than these chemical farmers who are dumping chemical nitrogen and phosphorus into the world's water supply.