We line the walls of the borehole with PVC or casings to keep the wall from collapsing throughout the lifetime of the borehole. Continuous casing are used all through the hole except where the aquifer(s) is located, at the aquifer zones, we use slotted casings to allow water to percolate into the drilled well.
Gravel Packing
We insert gravel sand between the borehole walls and the casings. Gravel pack filters soil and other impurities, and keeps the casings firmly in position.