In ground vertical barriers or venting systems

All impermeable barrier systems will require an assessment of the risk of uncontrolled gas migration along the length of the barrier and around the ends. If necessary, venting wells can be provided at the ends to manage this risk. The effect of barriers on groimdwater flow also requires careful assessment. 

A wide range of barriers and venting systems is available ranging from continuous impermeable barriers to venting systems with discrete venting nodes such as an array of boreholes. A summary of the most commonly used techniques is provided in the following pages. 

Excavate trench and use bentonite slurry to support excavation 

Insert membrane panel Into cement bentonite If required 

Cover surface of wall with protective clay or concrete layer 

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