restoration and replacement of seepage water drains
building of single and tandem shafts on landfill sites
advantage of tandem shaft method:
less interruptions of regular landfill operations due to reduced working space requirements
avoiding of methan emissions due to airproof sealing of shafts over night
small amount of waste removal due to reduced intrusions into the landfill body
in the past: shafts with inner diameters more than 6,00 m were necessary to achieve the sufficient bend radius of new HDPE-drainage pipes. However there were plenty emissions of gas and relocation of waste.
today: by unsing the tandemshaft-method two shafts are installed side by side and are connected by a tunnel on the bottom. Daily airproof sealing against methan emmisions are feasible.
here you will find more detail information about the tandem shaft-method
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