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questions about co-mingled compost testing and then some...



Does anyone know when in the analysis of co-mingled compost takes
place?  Is it before or after the batteries and other materials in the
mix begin to corrode?

I've learned that a serious problem with analytical data from MSW
compost is that it does not typically pick up these heavy metal levels
in the analysis because the batteries are often still intact when the
test is done, only to decompose over time and leak their toxic contents
years later.  

It is my understanding that mixed waste composting basically takes the
commingled solid waste stream, commercial and residential, and processes
it into smaller particles that are subsequently composted.  This is
contrasted with source-separated composting which takes yard trimmings,
food scraps, non-recycled paper, and commercial organics before they are
commingled.

Mixed solid waste is high in paper and generally very dry, so that many
companies use sewage sludge to provide moisture and nitrogen.

Again, it is my understanding that hammermilling systems shred plastics,
batteries, and such into little bits that may ultimately contaminate the
compost.  Other systems, I've heard tell, twist plastics into tiny
toothpick-like bits.  And, there are companies that sell dyes to color
compost the desirable dark brown or black color characteristic of earth
rich in organic matter.

Mixed waste composting will still have the full gamut of heavy metals,
particularly metals from household batteries such as mercury, lead,
nickel, cadmium, and zinc.  I understand that PCB levels in mixed waste
compost are often over 10 PPM as well, of which I and many states have
concerns with levels over 1 PPM.  Moreover, the USEPA does not regulate
mixed waste compost!

The fact is that household batteries are in mixed waste, and that they
are concentrated into a mixed waste compost.  It is also a fact that
they are high in heavy metals, and that if they are not removed, they
contaminate the compost to levels far in excess of even the most liberal
guidelines, much less the EPA 503 sludge rules which are liberal
compared with those in the Netherlands and Germany.

We have learned from the Seattle Times series how hazardous wastes
become fertilizer and the consequences of this action to farmers health,
the health of the fields, and grazing animals.
http://www.seattletimes.com/todaysnews/browse/html97/fert_070397.html

How will the recycling of industrial or municipal solid waste into
compost affect the health of farmers and their families, communities
down wind, especially when dust blows or fields are burned, such as with
sugar cane?  

Will the soil to dust to lungs or hands to mouth series poison our
children, ourselves, as well as the food chain?  Does this sustain
agriculture or sustain disposal of such materials?  My concerns and
others have been echoed in The Case for Caution.
http://www.cfe.cornell.edu/wmi/PDFS/PDFS.html  

Susan Snow


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