(best examples and good practices) on household organic waste ...

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majority of cases <strong>and</strong> the main waste treatment method for countries such as
Greece.
L<strong>and</strong>fill sites have to be well designed to prevent surface water <strong>and</strong>
groundwater pollution, to minimize all impacts from operations <strong>and</strong> to
facilitate site closure, <strong>and</strong> post-closure care. L<strong>and</strong>fill system design report must
contain: the suggested site boundaries, buffer area, waste fill area <strong>and</strong> contours,
surface water control works, on site roads <strong>and</strong> structures, final cover design,
design of liner <strong>and</strong> leachate collection system <strong>and</strong> l<strong>and</strong>fill gas control works,
monitoring facilities for groundwater, leachate <strong>and</strong> surface water, site closure
<strong>and</strong> post-closure care facilities (Botlin., 1995). When designing l<strong>and</strong>fill site the
following characteristics must be considered: the geology, hydrogeology,
topography, drainage, <strong>and</strong> permafrost of the site <strong>and</strong> transport facilities.
(Ontario’s Ministry of the Environment.,2010)
3.3.2. Configurations of sanitary l<strong>and</strong>filling
Sanitary l<strong>and</strong>fill is an engineered facility that needs detailed planning, careful
design <strong>and</strong> efficient operation as to minimize potential environmental
problems. There are three configurations of sanitary l<strong>and</strong> filling, depending on
the l<strong>and</strong>fill site topography: the area, the ramp <strong>and</strong> the trench method.
In the area method, waste is spread on the ground <strong>and</strong> then compacted to 2
meters. Waste can be stacked into different layers with this method. To cover
compacted waste soil or synthetic material is used. It is usually put after each
operation day or more often. The ramp method is a kind of the area method.
It is mainly used for sloping l<strong>and</strong>. Wastes are spread <strong>and</strong> compacted on a slope.
The trench method is the preferred method for disposing waste by l<strong>and</strong> filling.
It is the most economical <strong>and</strong> manageable plan. It’s used for flat or gently
sloping l<strong>and</strong>. In the trench design trenches are dug twice as wide as the
tractors. The waste is then placed in <strong>and</strong> then soil is added to cover it. When
selecting the waste to put in the trench it is important to separate wet wastes
from dry waste (Council of European Professional Information Societies –
CEPIS., 2009).
3.3.3. Mechanical Biological treatment
Prior to l<strong>and</strong>filling sometimes Mechanical Biological Treatment (MBT) is
undertaken. Such pre-treatment can lead to the material to be l<strong>and</strong>filled being
relatively friendlier to the environment. There are four stages of this process:
waste input <strong>and</strong> control, mechanical conditioning, biological treatment <strong>and</strong>
emplacement of treated waste at a l<strong>and</strong>fill. The mechanical stage is to sort out