The Swiss have always been highly environmentally aware, and for a long while have looked after their environment in an exemplary fashion.
The 'Guidelines to waste management in Switzerland' ( EKA, 1986 ) were set in 1986, well ahead of many states. One necessary objective of this as a code of good practice has been that all waste management procedures have to provide materials which either are re-usable or can be disposed of in a landfill without any negative or damaging environmental impact for long term periods.
This kind of landfilling would be called 'final storage' and the wastes in the final storage must of course by inference have 'final storage quality'. Emissions from a final storage quality landfill must be a close fit with the quality in the natural environment without any additional treatment. Another vital objective of the Swiss waste management policy is that each generation handles its waste to a standing of last storage quality. So the reactions in a landfill to take it to final storage quality need to be rapid enough to all be completed within 30 years, and preferably less.
As an effect of this policy, has each borough's solid waste landfills been shown to be able to reach the final storage quality inside about thirty years after disposal? The final storage idea focuses principally on the solid waste itself stabilizing so that the next generation will not have to rely instead upon the synthetic or natural barriers round the landfill body, and the answer is a resounding no!
The landfill body has to reach an 'inert' state so the emissions from the landfill have compatibility with the environment for long term periods irrespective of the retardation and attenuation capacities of surrounding materials. However, this inert state relies on geochemical properties of the landfill site materials. The concern is that compounds in the inert landfill body may become 'mobile' when the physical and chemical conditions in the landfill change, and this will still be damaging even centuries after the landfill was filled and revived.
A correct lining and a correct geological environment are basic must-haves for final storages. They are mandatory for containment, for monitoring and, last but not least, for environmental security reasons. Disposed of in a landfill, community solid waste ( MSW ) will ultimately come into contact water, which enters the landfill steadily through rain, even after capping as the seal cannot ever be perfect over a time period.
As a consequence of this contact, many chemical and microbiological reactions happen. Organic compounds can be changed to other organic compounds or inorganic compounds. Inorganic compounds can experience many chemical reactions and can be transformed to other inorganic compounds.
The products of these reactions and parts of non-reacted MSW can, and eventually will, be transported by leachate and by gas into the surrounding area. Additionally, many physical processes, like adsorption, dissolution, rain, etc, can happen at the same time.
Therefore, a MSW landfill can be accepted as a 'partly continual chemical and microbiological fixed bed reactor'. Now that's not a good thing to have in contact with groundwater which will often later be used as drinking water.
It's also considered as a treatment facility where the objective it is to get it to self-treat to a landfill body of last storage quality. Major research and monitoring of landfills is a new development, controlled landfills having existed for twenty years or so already.
The present controlled landfills therefore are still in the thorough reactor phase in which radical microbiological decompositions happen. The behaviour of landfills in this period can be considered approximately correctly using current models.
However, no experience exists with respect to the long-term behaviour (over even thirty years) of MSW landfills. Thanks to the highly complicated nature of the systems, a precise prophecy of long term behaviour of MSW landfills is nearly impossible.
So it is no exaggeration to say that long term leachate emissions from municipal solid waste landfills are unknown, and yet all over the world every day, new and bigger landfills are being built and filled with waste.
It is all a huge experiment and science has not determined the outcome. Even the Swiss, who are arguably some the most responsible guardians of the environment on the planet have fallen far short of their 1986 ideals.
How can we be so complacent? Shouldn't we all be worried?
Article is based upon the paper "Long-Term Leachate Emissions from Municipal Solid Waste Landfills, Hasan Belevi and Peter Baccini, Switzerland, presented at the International Symposia on Sanitary Landfills held in Sardinia (Italy)"
Many people find this fact to be of great concern. Is all of landfilling just a huge experiment which might cause huge problems in the future? Part 2 of this article is available were we further discuss landfill final storage quality. Go there now to read more!
Article Source: http://EzineArticles.com/?expert=Steve_Last
http://EzineArticles.com/?Long-Term-Leachate-Emissions-From-Municipal-Solid-Waste-Landfills-Are-Unknown&id=2552717
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