Bentonite Grout
Construction
A clay-based sealant pumped into the annular space around well casing to prevent surface water contamination.
Bentonite grout is a high-swelling clay slurry that seals the gap between the well casing and the borehole wall. Utah Administrative Rule R655 requires a continuous grout seal from surface down past any contaminating zone. A proper grout job blocks runoff, septic effluent, and shallow contaminated water from reaching the producing aquifer through the borehole annulus.