Environmental Engineering Reference
In-Depth Information
Fig. 3.6
Nyveli lignite mine tailings have been stabilized by legume, non-legume tree sincluding
biodiesel producing plants
3
Municipal Solid Waste Landfills
There are thousands of landfills exist all over the world. Most of these are mu-
nicipal solid waste landfills (rubbish pits) (Fig.
3.9
). Modern landfills (sanitary and
mine waste) are carefully engineered, structure and designed to isolate waste from
nearby natural resources, wildlife and people. These landfills are excavated/ dug
out of the ground and then the walls are sealed with layers of clay/ HDPE (for
e.g. bentonite/zeolites etc. which are by-products of mine waste) and coated with
high density plastic sheet or geotextiles as barrier prevent groundwater contamina-
tion from wastewater that is locked up in the pit that was dug to bury the waste.
These landfills are designed and engineered to stay dry inside, except for liquids
that ooze from small decomposable fraction of debris buried inside, and rainwater
that trickles through. As water trickles through a landfill, it dissolves chemicals and
other particles, creating a liquid called "leachate”. The landfills are designed and
engineered in such a way that the capping technology provides vents so as to re-
lease gas. The design and engineering of natural caps include landfill gas detection
meters which are monitored on regular basis. Monitoring wells around the site are
also dug for monitoring groundwater quality using lysimeters (Meißner et al.
2010
).
Landfills are provided with leachate collection system (Fig.
3.10
)
