A sand catcher is used in combination with the quality monitoring wells with bentonite collar. It serves to prevent sand from flowing past the filter before the collar is swollen.
The plastic sand catcher serves to prevent sand from running in or out of the space around the monitoring wells. As long as the bentonite sleeve is not sufficiently swollen, sand can still penetrate during the period when the bentonite slowly swells. The sand catcher keeps this from happening.
Sand-bentonite catcher for quality monitoring well, set of 50 pieces.