Some Ideas About Sewage
   
   My reading of a book by Joseph Jenkins called the Humanure Handbook has
clinched my developing conviction that the modern sewage mix of manure,
industrial cleaners, automotive fluids, photo chemicals and a huge amount of
water cannot be realistically rendered non-toxic; in spite of an impressive
and noble effort by government sewage treatment people. I believe that
anyone with the means should avoid contributing to this tragic mix, by
composting their manure and processing their grey water.
   Mr. Jenkin's book presents an argument for use of a sawdust toilet. The
toilet is a box with a toilet seat or a hole in the floor directing urine
and manure into a five gallon bucket. Each deposit is covered with a layer
of sawdust or similiar semi-dry vegetable matter (duff). A half inch layer
renders the manure odorless enough that even flies don't notice it. For most
applications a cover seals the bucket when not in use. Within two weeks or
whenever the bucket fills, the contents are added to the center of a
conventional outdoor compost pile of kitchen scraps, leaves and weeds, and
the heap covered with more duff sufficient to eliminate any odor. The
bucket must then be cleaned with duff or water well enough to be odor free,
ejecting the cleaning material onto the compost. In areas where sun or rain
are excessive a cover may be necessary to maintain the proper moisture
level. To maximize aeration the compost bin sides are made of netting or
boards with large gaps between them. The pile created this way heats to well
over 100 degrees and can safely be used for garden soil one year after the
last addition of manure. If the pile fails to heat, five to seven years may
be required to make the compost completely disease free.
   The book also describes some possible and hopeful approaches to grey
water management. His research indicates that only clorine and some toxic
metals may be completely resistant to bacterial and plant digestion in a
wetland lagoon; and that chemical free grey water is safe enough to use
directly on landscape plants and trees without processing.
   He makes a good case for a statement that a mix of manure and a large
amount of water cannot be rendered free of disease causing organisms by any
method; that manure must remain at the moisture level that the body gives it
and be mixed with high carbon plant material in a well ventilated place for
at least six months to make it harmless.
   He also verifies my concern that clorine is a terrible compromise
solution to the disease problem, damaging any ecosystem it enters and
contributing to certain organ cancers and respiratory problems.
   He has put most of the text of his book on the internet at
http://www.weblife.org/humanure, though omitting a description of the
sawdust toilet and compost pile and the chart of nitrogen/carbon ratios.
   In his chart I note that any green plant material is too high in
nitrogen to effectively balance the manure and urine for the air breathing
bacteria that prevent odor and produce heat. Dirt or finished compost also
fails. Dry Leaves and brown evergreen needles are adequate, brittle straw
and very dry weeds are better, and sawdust is totally ideal. Very dry
brittle blackberry vines work well for me. The test is how quickly the odor
vanishes and how well it remains gone.
   Mr. Jenkin's website provides a link to the state statutes about
composting human manure. The criteria in the Oregon law are very difficult
to meet without compromising the need for intense ventilation, preservation
of the bacterial heat and a bulky high carbon vegetable mass. Some compost
toilet salepeople insist that their toilet meets this challenge but I'm
doubtful. The federal authority people have shown support for Mr. Jenkin's
views but his method as he does it is definitely illegal in Oregon. I
believe a compost pile in a shallow waterproof hole with a rain cover and
with misquito netting on all sides may meet enough of Oregon's criteria to
be allowed in some counties but I have not discussed this with any building
code people out of fear of attack by them.
   
                                   Eric Michener


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