Many owners and agencies are recognizing the serious environmental impacts of dewatering and are placing severe restrictions on the discharge and removal of ground water.
Frozen soil is impermeable. Once fully formed, ground water and/or contaminates will be unable to move through the frozen wall. The goal of each system design is to give the contactor a “dry excavation” even in soils that are water saturated or well below surrounding ground water.
Any probability that ground water may infiltrate from below the frozen soil perimeter wall is addressed by investigating the underlying soil’s permeability. The design engineer, using computer analysis, can estimate the probability of any seepage. To greatly reduce or eliminate any ground water seepage, the freeze pipes are installed deep enough to penetrate low permeable soils or they’re installed at angles to create a frozen “bottom.”