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[greenyes] RE: Portola Valley's new program
Thank you Karin for posting the additional information from Richard
Gertman on the Portola Valley program.  I have two preliminary comments:

1) Richard noted that many years back a pilot program in Guelph, Ontario
found that more material was diverted from landfill in a 2-sort wet/dry
system (compostables & recyclables) than a 3-sort system (garbage,
compostables, and recyclables).  Guelph operated a two-sort system for a
number of years.  However, recently, Guelph abandoned the two-sort
system and moved to a 3-sort system of garbage, compostables and
recyclables.  I am not very familiar with the program and would welcome
comments from the people from Guelph as to why they made this change,
but I believe that the intention was to provide cleaner "dry" waste for
sorting recyclables, and that Guelph expected to significantly increase
diversion by making the change.  Here is a web site that gives more
information on how they currently sort waste for collection:

If someone from Guelph wants to comment on this but is not on the GRRN
listserve, send your reply to me and I will post it.

2) What sort of compost can you get from a facility that co-composts
garbage and yard debris?  Our experience in Oregon is that the compost
derived in this way is poor quality, and will not meet reasonable
standards for use in residential or agricultural applications.  Over a
decade ago, the Portland Metro area had a large mixed waste composting
facility built by Riedel.  The facility included pick-lines for removing
contaminants and recyclables, initial composting using a Dano Drum
system, followed by composting under shelter using an aerated floor,
followed by curing in piles and further screening to produce product.
The system failed to produce quality compost.  The compost failed to
meet the permit-required standards for things such as lead, and there
was too much glass and small pieces of plastic in the product.  The
compost could only be used for landfill cover.  After a couple of years,
the facility closed and the company went bankrupt.  I would worry that
the facility that composts Portola Valley's material might have the same

Peter Spendelow
Oregon Department of Environmental Quality

Richard Gertman, who authored the article found at
sent the following comments to expound on the article.  I don't think
got through to the Greenyes listserve, so here they are:

Many years back the good folks in Guelph, Ontario found that more 
divertable material was landfilled in a three sort (recyclables, 
compostables and garbage), than from a two sort + residue (recyclables

Richard Gertman
Environmental Planning Consultants
1885 The Alameda, Suite 120
San Jose, CA 95126-1732

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