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[GreenYes] Glass
    There has been much discussion of whether glass should be included in
curbside recycling programs in the future.

    In an ideal world, following the global perspective that Jeff has
clearly laid out, glass ought to remain on the truck.

    As we move from that ideal world and face more crass political
pressures, however, there are risks in simply ignoring practical realities.
In some areas of the country such as we are currently observing in New York
City, if recycling is to survive, a more cost-efficient system that does not
give proper recognition to externalities may need to be designed. Otherwise
the entire program in those areas is at risk of either being cut, or
(perhaps worse) trimmed so severely such as in collection frequency and
education, that its ultimate denouement will inevitably follow and be
misinterpreted as meaning that recycling does not work.

    That climate makes us confront choices that we would prefer not to face,
but our predilections are not of concern to the controlling winds of
fortune.  There are decision-makers who have little sympathy for the
environmental issues that recycling responds to, and, after nearly a decade
with "the wind at our backs," it is no longer clear that there is sufficient
public outrage in all of those areas to chasten errant public officials with
sufficient negative reaction to alter the final decision.

    But, being forced into a box such as this need not be all bad and there
is an opportunity to make some lemonade out of a lemon.  For although Jeff
points out the often ignored environmental considerations in the production
of a glass container, on the full spectrum of materials in the market, glass
is clearly one of less concern than most others.

    Moreover, and this is where I want to refocus our attention, the already
existing cost pressures have resulted in collection and handling practices
in a large swath of the country that have reduced the recovered glass to
non-sortable rubble suitable only for aggregate substitution before it can
be color separated for bottle-to-bottle recycling. Here in Madison and Dane
County, Wisconsin, for example, the county has contracted processing with a
waste company and 67.2% of the glass stream is mixed, and therefore,
generally not capable of realizing the environmental benefits from
substituting cullet for virgin feedstock in new bottle production.

    Even more important is the fact that, once discarded, glass is inert and
poses no environmental threat in a landfill.  This is in stark contrast to
not only the toxic compounds commonly used in our waste, but also with
regard to the enormous volume of organic material, most of which is
unrecovered paper, along with food scraps and leaves and grass.

    In past postings, I've described the reasons why we are unable to safely
manage decomposable matter that rots in the landfill, generating the
bioaccumuative methyl form mercury, a nerve gas, and the terrible greenhouse
gas methane which also transports the carcinogenic VOCs into the atmosphere.
And almost all of these landfill gases are released uncontrolled into the
atmosphere.  The organic material also creates leachate that mobilizes the
toxics in the waste to, after the barriers fail, contaminate drinking water.
This is why Europe has already begun the process of banning organics from
landfills.  We urgently need to confront the need to aggressively seek to
divert more and more of the organic fraction away from the landfill.

    In that context only, some cold facts need to be considered.  There are
very very significant cost savings in collection -- the greatest part of our
cost structure -- if glass is removed from the truck because the presence of
glass impedes the ability to compact, and compaction is the standard
technique to reduce collection costs by keeping the vehicle on the route

    We have done extensive studies that demonstrate that carefully
calibrated light compaction (about 2:1 instead of 10:1) can be used to
realize 25% reduction in route requirements without any greater glass
breakage than uncompacted semi-automated collection (P. Anderson, "The
impact of light compaction on curbside collection," Resource Recycling, May
1996). However, that study pointed out how carefully the program needs to be
crafted to insure that it is done properly, and, that, if this is not done,
rampant glass breakage would occur.  That is to say, light compaction in the
real world in which many of our recycling programs are run under franchise
by garbage companies with a different focus that ourselves, is going to
result in massive fractions of unsorted mixed glass that does not produce
bottle-to-bottle environmental benefits.  Moving to heavy compaction for
recycling, if glass were not present, would result in even more significant
collection cost savings than light compaction.

    Also, in the MRF the abrasive glass shards are a costly nightmare for
conveyor maintenance.

    But, were we in areas where the political pressures leave no practical
alternative to shift from glass to something like residential mixed paper,
we would:

    1) Open the world of cost saving opportunities from heavy compaction.
    2) Substitute a material that is, in general, greater in weight than
glass, thereby improving overall recovery rates.
    3)  Make landfills far less a hazard than they currently are.

    Of course, even where glass is not under cost pressure, the need to push
our programs to recover out more of the organic fraction, such as San
Francisco and Nova Scotia and a few other places are already doing,  needs
to be pursued aggressively on its own merits.


Peter Anderson
4513 Vernon Blvd. Suite 15
Madison, WI 53705
Ph:    (608) 231-1100
Fax:   (608) 233-0011
Cell:   (608) 345-0381

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