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urine is sterile, but ...

paul wheaton
steward

Joined: Apr 01, 2005
Posts: 15609
Location: missoula, montana (zone 4)
    ∞
I seem to remember hearing something once that contradicted the whole thing about urine being sterile.  Something about once it ages a bit, problems arise.

Anybody know anything about that?

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Joined: May 09, 2008
Posts: 40
I think the issue is that once it is out of the body it becomes infected with all sorts of bacteria from the environment, and it happens very quickly.
Kelda Miller


Joined: Jun 30, 2007
Posts: 763
    
    1
I'm not sure if bad bacteria would accumulate with 'aging' urine, but I seem to remember an interesting factoid about dying leather white with aged urine and the ammonia it turns into. I don't think much bacteria could survive in ammonia?


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paul wheaton
steward

Joined: Apr 01, 2005
Posts: 15609
Location: missoula, montana (zone 4)
    ∞
Wouldn't the ammonia kill off damn near anything?
paul wheaton
steward

Joined: Apr 01, 2005
Posts: 15609
Location: missoula, montana (zone 4)
    ∞
kelda wrote:
I'm not sure if bad bacteria would accumulate with 'aging' urine, but I seem to remember an interesting factoid about dying leather white with aged urine and the ammonia it turns into. I don't think much bacteria could survive in ammonia?


I think that's from one of those clan of the cave bear books.  Good books!  Lots of little interesting tidbits to learn along with an interesting story!
Jeremy Bunag
volunteer

Joined: May 30, 2007
Posts: 231
Location: Central IL
Yeah, it's much like anything sterile.  It's sterile until you open it, or expose it to a non-sterile environment!

Urine makes a nice breeding ground for "stuff," having some nice stuff for bacteria to eat (hence it's "green-ness" for the compost pile).

I don't know what populates it though...
Ben Souther


Joined: May 08, 2008
Posts: 32
My daughter tells me, she learned in Latin class, that the Romans used to keep around until it turned into ammonia and then use it for toothpaste.

Yummy!
Marilyn Queiroz
steward

Joined: Apr 03, 2005
Posts: 60
Urine is normally sterile while it is still in the human body (except when you get a urinary tract infection -- a UTI). However, it is a very good media for bacteria, so once it leaves the body, bacteria thrive on it. This is why, if you don't flush after you pee, the water begins to turn cloudy and smell pretty rank after a couple of days (even without fecal matter). After you flush, most likely you'll see a ring of slippery "scum" left on the toilet bowl ... frequently a pink one. I'm not talking about white mineral rings left by hard water or well water iron-colored mineral rings.

Urine contains waste products from the body like creatinine, urea (a source of Nitrogen), uric acid, and other minerals (like Sodium, Potassium, Magnesium, Phosphorus) which are soluble in water as salts. Normally there is minimal Protein and/or Glucose.  Bacteria from the environment love these nutrients.

Typical bacteria which may invade the urinary tract are Escherechia coli, Pseudomonas species, and Klebsiella species, and Bacillus species.  Staph and Strep may also show up, although UTIs with these bacteria are less common. All of these are common in the environment. You very probably have some of each of them on your skin right now (when was the last time you washed your hands?).

The chemical formula for Ammonia is NH3 ... the 'N' stands for Nitrogen. The bacteria change the Nitrogen salts to ammonia. The urine pH changes from neutral to alkaline. Other bacteria oxidize the ammonia.  Some bacteria like cold, some prefer hot temperatures; some prefer acid environments, others prefer alkaline environments.

monica jenkins


Joined: Jun 27, 2008
Posts: 27
Location: Western Suburbs, Illinois
Ben Souther wrote:
My daughter tells me, she learned in Latin class, that the Romans used to keep around until it turned into ammonia and then use it for toothpaste.

Yummy!


Yet just another reason why the Roman empire failed. Perhaps it was the lead in their wine that convinced that aged urine would be a cool thing to clean their mouths with. Yeeesh. I am off to wash my hands!


"Participation is what is going to save the Human Race." Pete Seeger
Kelda Miller


Joined: Jun 30, 2007
Posts: 763
    
    1
Back to the whole aging thing

It probably doesn't work that way in a compost pile though, where its immediately absorbed by carbon and worked over by all sorts of other good bacteria. Once again why I like to pee  on the compost. I can't imagine it does anything but good things there.

(well, if this was the desert, I guess it could be adding salt. no worries about that in the pnw though!)
Leah Sattler


Joined: Jun 26, 2008
Posts: 2603
Some bacteria specifically break down ammonia and turn it into nitrogen don't they? So some bacteria must be able to tolerate it to some extent at least.
http://en.wikipedia.org/wiki/Nitrifying_bacteria


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Dave Boehnlein


Joined: Jun 10, 2007
Posts: 291
Location: Orcas Island, WA
    
    2
John Valenzuela has mentioned really good things about this book, but I haven't had a chance to purchase it yet.

http://www.liquidgoldbook.com/

It is all about using urine as part of your fertilizer regime.

Dave


Principal - Terra Phoenix Design
http://TerraPhoenixDesign.com
Leah Sattler


Joined: Jun 26, 2008
Posts: 2603
hmmmm....I finally figured out how to unwittingly involve my husband in my organic/natural/permie schemes thanks to this thread! My only needs are lots of beer and a sign designating where to relieve himself in the yard.......
paul wheaton
steward

Joined: Apr 01, 2005
Posts: 15609
Location: missoula, montana (zone 4)
    ∞
A bale of straw can be good too.
Susan Monroe


Joined: Sep 30, 2008
Posts: 1093
Location: Western WA
Nothing is sterile forever.  Actually, not even for very long.

What is important is to remember that spontaneous generation doesn't exist.  If you pee into a bucket of sawdust, then dump the contents into the center of an active compost pile, you're not going to suddenly have E. coli O157:H7, anthrax or bubonic plague suddenly pop up in the compost.  It has to physically BE there before it can grow.

Sue
                              


Joined: May 03, 2009
Posts: 461
Location: Inland Central Florida, USA
Sorry, I know this is an old thread.

I've actually run some small scale experiments on urine and urine that has been sealed up in a bottle for a period of time.

The whole urine is sterile idea is a little off.  The fresh urine of a healthy person is probably close to sterile and fine for many of the uses that people have put it to like cleaning wounds.

If the urine of a healthy person is sealed up and saved for a period of time, the urea converts to ammonia which will kill off stuff like e. coli that is likely to be in most any urine that comes out of a human body (we usually have enough of it on our skin to contaminate a sample.)  I ran tests where we even purposely contaminated samples to be certain that there was e. coli in it and after letting the sample sit sealed up till the pH reached 9, we then tested for e. coli and found none.  Fresh urine being tested, was positive for e. coli.  (Regular e. coli is in all of us since it lives in the intestines and is normal there, we only suffer from it if it builds up in too high of numbers in the wrong parts of our bodies, like the urinary tract causing a urinary tract infection.  Even when healthy, some small amount of e. coli is likely to get into urine.  The difference between healthy and a urinary tract infection is in the numbers.)

Please keep in mind that some one who is really sick will likely shed the disease pathogens in their wastes.  There are some of these that the high pH and ammonia don't seem to kill (heat would kill these but I don't know many interested in boiling urine.)  Salmonella, Typhus, and Strep are the ones I would watch out for when utilizing urine, any waste from people with those illnesses should be very well composted rather than used for anything else directly.

Keep in mind that when you pee in a bowl of water and let it sit open to the air, the dilution and access to air will make the ammonia conversion slower and so much more dilute that ya really just created a really food rich breeding ground for whatever bacteria might fall in so that comparison is not accurate.  Also, pee in a compost pile can help heat it up nicely and therefore kill off most pathogens and then the aging process should take care of the few lingering where the compost didn't get hot.  I firmly believe that urine is far too valuable to waste in a flush toilet, urine is the perfect compost activator, it is a great fertilizer if diluted appropriately and has many other uses.

I have even been running an experiment for over a year now akin to aquaponics but it is Pee Ponics where aged urine is used as the ammonia/phosphorus source for a flood and drain grow bed type hydroponics set up.  Bacteria in the gravel beds will convert the ammonia into nitrates for the plants.  Potassium and trace elements need supplementing as well as iron if the source water does not cause rust stains.  I have been using sea weed extract to add the potassium and trace minerals and the Pee Ponic system grows veggies just fine.  Basically it is running like a Fishless Aquaponics System.

One other thing to keep in mine when using urine for growing (and probably the main reason it is not acceptable for organic growing) is that any medications the people supplying the urine take, will be then passed on in the urine.


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Susan Monroe


Joined: Sep 30, 2008
Posts: 1093
Location: Western WA
Now, isn't that interesting!  It's exactly opposite to my assumption.  The odor is just from the pH rising, not the proliferation of bacteria.

I think the odor really increases with aging, and the mere idea of boiling urine makes my eyes water.

"PeePonics" -- have you mentioned that to Joel?  I'm sure he would get a laugh out of it.  But it does prevent the wasting of a valuable resource.

Sue
                              


Joined: May 03, 2009
Posts: 461
Location: Inland Central Florida, USA
about the aging urine, I know when sealed in a bottle the odor will be really strong/nasty when opening it to use, this is mostly the ammonia and whatever else.  If you go peeing in an open bucket and leave it sit out in the open, I expect the smell will get really strong but what I don't know is if there might be other bacteria that float around in the air that might be able to proliferate in the open bucket of urine so I can't say if the odor there would simply be from the ammonia or if there might be other nasties that get going to make the odor worse.  When you dilute with water and leave sit out in the open, that nastiness is probably due to more bacteria getting in there and causing the water to go septic.  This is why grey water should not be allowed to sit for more than a day since it will go septic and proliferate bacteria, hence grey water re-use should be as immediate as reasonable.

Pee Ponics seems to work quite well if you can get past the "Yuck" factor.
paul wheaton
steward

Joined: Apr 01, 2005
Posts: 15609
Location: missoula, montana (zone 4)
    ∞
I have read conflicting stuff about mixing pee and poop together. 

I tend to believe the folks that say it should be avoided:  keep the pee separate.  But I'm still fuzzy on "why".  My best guess is that the stuff in pee that makes for a great growth medium for bacteria and the like, could be a great growth medium for pathogens in the poop.

But that's just a guess.

Anybody have anything a bit more solid to stand on?

                              


Joined: May 03, 2009
Posts: 461
Location: Inland Central Florida, USA
Well it depends on what you are trying to do with the stuff.  If you want to use urine as fertilizer or something, It would be best to keep it separate.  It isn't that the urine provides any better media for growing bacteria or anything, you just want to avoid adding a higher load of possible pathogens by mixing the poo with it.

However, if you are gonna humaure compost, mixing the urine and poo in a sadust bucket toilet is just fine as the urine acts as a really good compost activator to make sure you get good hot humanure composting going.  In this case you want to have enough urine mixed with the poo so that the compost will get hot enough to take care of most possible pathogens quickly.

So, if you want to use the pee directly as fertilizer, keep it separate!

If you are humanure composting, mix probably half the pee at least into the compost along with the poo so it will compost properly.
paul wheaton
steward

Joined: Apr 01, 2005
Posts: 15609
Location: missoula, montana (zone 4)
    ∞
So there's the thing.  The humanure thing.  I should have said that.

My thinking is that if you have a pee separator, then you don't need nearly as much sawdust.  And, I seem to recall somewhere that somehow when you mix the pee with the poop it becomes something far more problematic than if you keep them separate.  But i cannot remember what the problem was.  Nor can I find that reference.  So I'm hoping somebody would enlighten me.
                              


Joined: May 03, 2009
Posts: 461
Location: Inland Central Florida, USA
I have a feeling that you will still need the same amount of carbon material for the compost even if you bottle the pee and then add it to the compost separately from the poop in the sawdust bucket.  However if you are short on sawdust to use in the buckets and don't want to empty them as often, then peeing in a bottle might make the buckets a bit lighter and need a bit less sawdust per number of days used.

There has actually been a lot of discussion of urine separation on the Humanure Composting Forum on Joseph Jenkins (Author of the Humanure Handbook) web site.  He believes that peeing right in the bucket is a fine way to do it and I agree.  However, much of the discussion there centers around how the urine can cause such a strong smell so many people want to separate it.  I admit that the plastic buckets can have a pretty strong odor till after they dry in the sun a bit.  It is important to note that turds in sawdust without the urine, don't compost very well.  You wind up with sawdust coated turds.  The nitrogen content of the urine is an important part of getting good hot compost.

I personally don't find the idea of urine separating toilets to be very appealing, I've become quite comfortable with a simple sawdust bucket.  To help our sawdust supply last longer, we use the shredded junk mail in the buckets as well though sawdust does cover odor better.  Anyway back to the urine separating idea, it seems that it would require more containers to clean and extra apparatus for the toilet and how do you seal it between uses and how do you wash the tubing running to the urine collection container.  I suppose most of my resistance is due to being unfamiliar with the methods.  I'm sure there must be perfectly acceptable ways to do it since I think there are some places in Scandinavia that use urine as fertilizer on a large scale.

Anyway, I guess for now I'll stick with my funnel and bottles for when I want to save some urine for the Pee Ponics or for use as garden fertilizer.
paul wheaton
steward

Joined: Apr 01, 2005
Posts: 15609
Location: missoula, montana (zone 4)
    ∞
I was just reading the Oasis with Greywater book where the author talks about the use of urine to fertilize plants.  In it, he points out the enormous salt content of urine, and that while urine is a great fertilizer in areas with plenty of rainfall, areas that get less than 30 inches per year would have too much salt buildup. 

I suspect that the salt issue is going to be the same even if you compost it as suggested in the humanure book.

So while the compost might be a lovely thing in the short run, it does seems that after 10 to 100 years, it might turn out to have been a really bad idea.

                              


Joined: May 03, 2009
Posts: 461
Location: Inland Central Florida, USA
So eat less salt.

Actually, there is far less salt to build up from the use of human urine than there is from chemical fertilizer salts (that is what most of the chemical fertilizers are.)  There are many manures that tend to be high in salt as well.  The trick is to dilute appropriately and spread it around rather than using it really heavily in a single area.  If the only fertilizer you use is urine then you will have a problem.  If you add other sources of nutrients as well as plenty of mulch and compost, then it should be fine.

I definitely think using the urine as fertilizer or in the compost is a far better use for it than putting it in a clean bowl of drinking water and sending it "away" to be dealt with by "some one else" or flushing it into your own septic system where the contents are leached back into the ground waters.
paul wheaton
steward

Joined: Apr 01, 2005
Posts: 15609
Location: missoula, montana (zone 4)
    ∞
I think the problem is a bit more complicated than "eat less salt."

I guess the trouble with salt is the accumulator factor.  Large portions of the world struggle to grow anything at all because of the salt content in the land.  Naturally occurring salt. 

Since salt is such a teeny-tiny molecule, I get the impression that there is not an easy way to separate it from everything else. 

So .... yeah ... salt in your water or salt in your soil.  Tricky, tricky, tricky ...

Do you have a link to the humanure discussion of urine separation?

                              


Joined: May 03, 2009
Posts: 461
Location: Inland Central Florida, USA
I don't remember where all the specific discussions about urine separating were and it really has been a long time since I spent any time over oh those message boards but here is a link to the Humanure Message boards
http://www.jenkinspublishing.com/messages/
paul wheaton
steward

Joined: Apr 01, 2005
Posts: 15609
Location: missoula, montana (zone 4)
    ∞
Found it. 

There seems to be a lot more discussion here than over there.

An interesting point about the plant hormone auxin was raised.  Interesting.  Another good reason to dilute it. 

The salt point was brought up there too. 

I wonder ....  I would sure like to see some more definitive info on the salt aspect.  It seems that if you are in an area that typically has little to no salt trouble and you just make sure to avoid peeing in the same spot over and over, then it should be mitigated.  Maybe the issue is compounded by the number of people per acre?

                                      


Joined: Aug 23, 2009
Posts: 25
Regarding the "sawdust covered turds", even if you are composting humanure, you still have to treat the pile like a regular compost pile and make sure you add some "greens" to all the "browns" so everything breaks down properly.  Jenkins likes urine as the activator but if you are separating the urine out, you'd have to add something like grass clippings or garden waste to keep things hot.

As for urine, it's 95-97% sterile water. It's amazing really that such a small amount of minerals and waste could make it smell so strong!  Still, around the world urine is considered fairly benign.  Some folks use it medically as in urine therapy ( http://en.wikipedia.org/wiki/Urine_therapy ) and they even use urine as a source of water on the Space Station...after it's been processed of course.  Still, no matter how you say it, they are drinkin' pee.  Now that's recycling!
paul wheaton
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Joined: Apr 01, 2005
Posts: 15609
Location: missoula, montana (zone 4)
    ∞
Poop is still gonna be your "green".  I don't know what the C:N ratio is for human poop, but I cannot help but think it is heavier on the N than the 30:1 needed for optimal compost.

Further, I suspect that even if you separate out the pee, some is still gonna get mixed in with the poop.
Joel Hollingsworth
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Joined: Jul 01, 2009
Posts: 2103
Location: Oakland, CA
Re: balanced composting:  I would think a bigger problem would be maintaining loft, if it's just feces, paper, sawdust, and ash.  None of those is particularly good at maintaining air flow...

I've heard coffee chaff and rice husks work well, and I know some people are experimenting with minor additions of charcoal.

Paul: A lot of the trouble in de-salination isn't the size of the molecule, but the inherent messiness of the chemical reaction that salt undergoes with water.  Instead of a predictable crystal of NaCl, we have multitudes of Na ions, each complexed with many water molecules and perhaps with an OH ion as part of the entourage, and floating free of that, a similar number of Cl ions complexed with many more water molecules and maybe an H3O ion.  There are quite a number of details to be sorted out if order and purity are to be restored.

Sorting out astronomical numbers of details is, necessarily, hard work.  For any chemists out there, the equation for that is G = U + pV - TS. 


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nancy sutton
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Joined: Feb 22, 2010
Posts: 333
Location: Federal Way, WA - Western Washington (Zone 8 - temperate maritime)
    
    9
Just BTW, I recall reading on-line several years ago about someone in Africa who thought they'd found a cheap insecticide or herbicide (can't remember which) which was aged urine.  Heard no more about it, so it must have gone nowhere.


It's time to get positive about negative thinking    -Art Donnelly
                              


Joined: May 03, 2009
Posts: 461
Location: Inland Central Florida, USA
Humus wrote:
Just BTW, I recall reading on-line several years ago about someone in Africa who thought they'd found a cheap insecticide or herbicide (can't remember which) which was aged urine.  Heard no more about it, so it must have gone nowhere.


LOL, well, if you use aged urine on the weeds, you might find that they grow unless you manage to use so much that you burn them.  Vinegar is probably more effective as a herbicide. 

As an insecticide, well I suppose if you were to carefully fertilize plants with appropriate amounts of diluted aged urine, you might find the plants are stronger and able to fight off pests better. 

However, I don't see it being all that effective for either of those things directly.  It is a fairly good fertilizer and compost activator though.
Michael Duhl


Joined: Mar 11, 2010
Posts: 31
Location: Ohio river valley
paul wheaton wrote:
Poop is still gonna be your "green".  I don't know what the C:N ratio is for human poop, but I cannot help but think it is heavier on the N than the 30:1 needed for optimal compost.

Further, I suspect that even if you separate out the pee, some is still gonna get mixed in with the poop.


C/N= 6-10, %N=4-6 and %C=40


Rocketstoves, cob, ferrocement, strawbale, all make the world go round.
paul wheaton
steward

Joined: Apr 01, 2005
Posts: 15609
Location: missoula, montana (zone 4)
    ∞
I thought just occurred to me.  Perhaps the problem of mixing the two together is that while poop has pathogens, pee has lots of pathogen food.  By separating them, you are killing off your pathogens faster.

Not sure if this is true, but it is my theory of the moment.

                        


Joined: Jul 07, 2010
Posts: 508
someone actually did some research on mixing pee and wood ash, apparently. http://www.sciencedaily.com/releases/2009/09/090902112750.htm    supposedly the combination is as effective in the short term as commercial fertilizer but of course long term has some beneficial results, esp if your soil is sandy and acid.  The article doesn't say anything about the possible buildup of salts though.

Another  article I read said that this was the main possible problem with using wood ash. Since much of the nutrient is water soluble but some is not, the land can develop a problem with various salts buildup especially if not incorporated into the soil somewhat, or so government research suggests. I would think this might be exacerbated by using urine?

I am trying to build up land and I have been saving wood ash for a year trying to find out just what the story is and I need to do something with it! Now this suggests it would fit very nicely into the use of pee as well...maybe a second justification for trying (somewhat) to separate the urine from the feces in a composting toilet, the first possibly being  making the material too wet to compost properly if left as it occurs? (Something suggested as a possible problem to be dealt with in a manual for building a CLivus Multrim type system).
Lonicera McCoy


Joined: May 26, 2010
Posts: 13
Per my microbiology class, urine is not sterile.  Perhaps it is sterile in the bladder but the urethra is home to a bacterial community.  In fact, the physical act of urine flushing out the urethra is part of what keeps us from having urinary tract infections due to bacterial overgrowth there.  The urine takes bacteria with it when it leaves the body. 

The bacteria are not necessarily a bad thing, even.  We actually have 10 times more bacterial cells in/on our bodies than we have human cells, creating our very own ecosystem.  Usually the bacteria do not harm us and sometimes even help us.  However, disruptions in that ecosystem can cause an imbalance in which formerly harmless bacteria become pathogenic.
ronie dee


Joined: Mar 04, 2009
Posts: 588
Location: Cosby MO
    
    2
Urine is sterile until it leaves the bladder (provided there is no bladder infection). After leaving the bladder urine picks up bacteria just like Lon said.

These bacteria are normal flora and don't harm us on the body unless they grow unchecked for some reason.

Male urine has less bacteria in the urethra (usually). Don't ask me to explain ( i would be speculating) - I know it from actual incubation tests in microbiology.


Sometimes the answer is not to cross an old bridge, nor to burn it, but to build a better bridge.
paul wheaton
steward

Joined: Apr 01, 2005
Posts: 15609
Location: missoula, montana (zone 4)
    ∞
This topic is covered a bit in podcast 017

This podcast covers a LOT of different topics!

As mentioned at the beginning of the podcast: email signup.

We start off reviewing the movie "Food Matters".  The premise is that many diseases can be resolved by food choices.  And this has been discussed several times at the forums.  A good start is my thread on eliminating medication with polyculture; and the thread about beating  cancer

We talk about raw food; local food; the missoula urban demonstration project; composting toilets; outhouse; urine diversion; women peeing outdoors; hugelkultur; rain barrels; greywater; commercial compost; art ludwig; pee powered cars; jean pain technique; poop beasts.
paul wheaton
steward

Joined: Apr 01, 2005
Posts: 15609
Location: missoula, montana (zone 4)
    ∞
At the spokane conference somebody raised a concern about hep C in urine.  I just did some research and:  it sounds like it could be possible, but even with somebody that has hep C and they pee on you, the risk is still so low that hospitals and other medical environments don't protect their workers from this. 

It sounds like hep C is dominantly a blood-to-blood thing.  Therefore, I suspect that it's lifespan outside of the body is near zero.  So if a person with hep C pees on the ground and then somebody barefoot steps on that spot 60 seconds later, I think the second person is 100% safe.

I do think it is worth making a list of possible stuff that a sick person might squirt out and see what is the worst case scenario.  Or if there is anything to be worried about.  So far, this bit about hep C has been the closest I have ever been to being concerned in this space and it sounds like there is zero to worry about.


Charlie Rendall


Joined: Oct 28, 2011
Posts: 26
Location: Lake Atitlán, Guatemala
    
    2
paul wheaton wrote:My thinking is that if you have a pee separator, then you don't need nearly as much sawdust.  And, I seem to recall somewhere that somehow when you mix the pee with the poop it becomes something far more problematic than if you keep them separate.  But i cannot remember what the problem was.  Nor can I find that reference.  So I'm hoping somebody would enlighten me.


The problem for me when my pee separator goes out of action (usually it gets blocked with carelessly dispensed sawdust) is that it stinks up the toilet very quickly, even if I put in extra sawdust. The pee soaks to the bottom of the poly oil barrel and makes great compost (it looks like earth after only a month) but it smells worse, attracts more flies and puts our visitors off using it - could that be the only problem with it or are you thinking of something more sinister?

Apart from that I've had no problem and I'm considering removing the separator and just emptying the barrel more often - it seems the lesser of the two evils. I decontaminate the sawdust/poop mix by leaving it covered for 6-12 months then hot-composting it with lots of other stuff, but just today I dunked a fresh batch in the bottom of a new tree pit we dug and that way I don't have to worry about decontaminating. We have a very diverse group so I'm not worried about any chemicals building up.


Charlie Rendall - http://www.returntotheforest.org

Bamboo Builder & Director of "Return to the Forest" courses, Lake Atitlán, Guatemala.

Living in the land of eternal spring: 1600m altitude; tropical highlands with warm rainy summers & warm dry winters; lots of corn, beans, sweet potatoes, avocado, coffee, hog plums, citrus, bananas and bamboo.
 
 
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