Solinst Model 615 [100929] Drive-Point Piezometer 6" (15cm). The Model 615 Drive-Point Piezometer is designed as an affordable method to monitor shallow groundwater and soil vapor in suitable conditions. The Drive-Points attach to inexpensive 3/4" (20 mm) NPT stainless steel drive pipe. The Drive-Points are designed for single use installations, and not for removal and reuse. Solinst Drive-Point Piezometers are most often installed as permanent well points. They can also be used for temporary, short term monitoring applications. Higher quality samples can be obtained when polyethylene or PTFE-lined tubing is attached to the stainless steel drive-point. Groundwater sampling and hydraulic head measurements can be taken within the tubing using small diameter equipment, as described here. Solinst Drive-Point Piezometers can be driven into the ground with any direct push or drilling technology, including the Manual Slide Hammer. To avoid clogging or smearing of the screen during installation, a shielded version is also available.