GeoTAP Method: Accessing Challenging Unconsolidated Injection Intervals

Roto-sonic (“sonic”) drilling is a unique method that allows environmental practitioners access to geologic formations and depths not previously achievable, and at advancement rates that outpace traditional drilling. Sonic drilling provides flexible and unique sample collection, mitigates down-hole contamination, and generates less investigative derived waste (IDW) than older drilling methods.

When direct push technologies (DPT) reach refusal in the subsurface, sonic is a great solution to advance into or past dense or coarse-grained units, e.g. glacial till, saprolite, urban fill, massive clay, cobbles, etc. The GeoTAP(sm) method, utilizing sonic equipment, was developed to address these tough geological formations. GeoTAP involves advancing sonic tooling to depth, applying an engineered backfill in lifts while simultaneously extracting the sonic tooling, and advancing DPT rods through the engineered column to conduct reagent/reactant installation just as you would in unconsolidated material. GeoTAP provides both access and product installation in a simple process. GeoTAP applications from sites in Massachusetts, New Jersey, New York, and South Carolina will be discussed.