PATHOGENIC POPULATIONS AND A TWO YEAR RETENTION TIME
DO'S AND DON'TS OF A THERMOPHILIC TOILET COMPOSTING SYSTEM
DO — Collect urine, feces, and toilet paper in the same toilet receptacle. Urine provides essential moisture and nitrogen.
DO — Keep a supply of clean, organic cover material handy to the toilet at all times. Rotting sawdust, peat moss, leaf mould, and other such cover materials prevent odor, absorb excess moisture, and balance the C/N ratio.
DON’T — Segregate urine or toilet paper from feces.
DON’T — Turn the compost pile if it is being continuously added to and a batch is not available. Allow the active thermophilic layer in the upper part of the pile to remain undisturbed.
DON’T — Use lime or wood ashes on the compost pile. Put these things
directly on the soil.
DO — Keep another supply of cover material handy to the compost bins for covering the compost pile itself. Coarser materials such as hay, straw, weeds, leaves, and grass clippings, prevent odor, trap air in the pile, and balance the C/N ratio.
DO — Deposit humanure into a depression in the top center of the compost pile, not around edges.
DO — Add a mix of organic materials to the humanure compost pile, including all food scraps.
DO — Keep the top of the compost pile somewhat flat. This allows the compost to absorb rainwater, and makes it easy to cover fresh material added to the pile.
DO — Use a compost thermometer to check for thermophilic activity. If your compost does not seem to be adequately heating, use the finished compost for berries, fruit trees, flowers, or ornamentals, rather than food crops. Or allow the constructed pile to age for two full years before garden use.
DON’T — Expect thermophilic activity until a sufficient mass has accumulated.
DON’T — Deposit anything smelly into a toilet or onto a compost pile without covering it with a clean cover material.
DON’T — Allow dogs or other animals to disturb your compost pile. If you have problems with animals, install wire mesh or other suitable barriers around your compost, and underneath, if necessary.
DON’T — Segregate food items from your humanure compost pile. Add all organic materials to the same compost bin.
DON’T — Use the compost before it has fully aged. This means one year after the pile has been constructed, or two years if the humanure originated from a diseased population.
DON’T — Worry about your compost. If it does not heat to your satisfaction, let it age for a prolonged period, then use it for horticultural purposes.
Fecophobes, as we have seen throughout this book, believe that all human excrement is extremely dangerous, and will cause the end of the world as we know it if not immediately flushed down a toilet. Some insist that humanure compost piles must be turned frequently — to ensure that all parts of the pile are subjected to the internal high temperatures.
The only problem with that idea is that most people produce organic refuse a little at a time. For example, most people defecate once a day. A large amount of organic material suitable for thermophilic composting is therefore usually not available to the average person. As such, we who make compost a daily and normal part of our lives tend to be “continuous composters.” We add organic material continuously to a compost pile, and almost never have a large “batch” that can be flipped and turned all at once. In fact, a continuous compost pile will have a thermophilic layer, which will be located usually in the top two feet or so of the pile. If you turn the compost pile under these conditions, that layer will become smothered by the thermophilically “spent” bottom of the pile, and all thermophilic activity will grind to a halt.
In healthy human populations, therefore, turning a continuous compost pile is not recommended. Instead, all humanure deposits should be deposited in the top center of the compost pile in order to feed it to the hot area of the compost, and a thick layer of insulating material (e.g., hay) should be maintained over the composting mass. Persons who have doubts about the hygienic safety of their finished humanure compost are urged to either use the compost for non-food crops or orchards, or have it tested at a lab before using on food crops.
On the other hand, one may have the need to compost humanure from a population with known disease problems. If the organic material is available in batches, then it can be turned frequently during the thermophilic stage in order to enhance pathogen death. After the thermophilic stage, the compost can be left to age for at least a year.
If the organic material is available only on a continuous basis, and turning
the pile, therefore, is counterproductive, an additional year-long curing
period is recommended. This will require one more composting bin in addition to
the two already in use. After the first is filled (presumably for a year), it is
left to rest for two years. The second is filled during the second year,
then it is left to rest for two years. The third is filled during the third
year. By the time the third is filled, the first has aged for two years and
should be pathogen-free and ready for agricultural use. This system will create
an initial lag-time of three years before compost is available for agricultural
purposes (one year to build the first pile, and two more years retention time),
but the extra year’s retention time will provide added insurance against
lingering pathogens. After the third year, finished compost will be available on
a yearly basis. Again, if in doubt, either test the compost for pathogens in a
laboratory, or use it agriculturally where it will not come in contact with food
Source: The Humanure Handbook. Jenkins
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