Multi-Level VW Piezometers

Multi-level VW piezometers system solves or avoids the problems associated with traditional multi-level piezometer installations:

• In the traditional method, placing sensors at their intended depth is difficult, and the difficulty increases with the number of sensors. With the multi-level system, piezometers are installed in line with PVC pipe. The pipe controls the elevation and relative spacing of the piezometers.
• In the traditional method, placement of sand intake zones and bentonite seals is time-consuming and uncertain. The multi-level system eliminates sand intake zones and bentonite seals. Instead, the entire borehole is filled with bentonite-cement grout.
• In the traditional method, signal cables from the piezometers pass through the seals that isolate the various intake zones. The cables can form channels for the migration of water between zones. With the multi-level system, signal cables from each piezometer run to the surface through the PVC placement pipe. The pipe itself is watertight and is later filled with grout. This eliminates communication between zones.
• In the traditional method, cables can be twisted and permanently damaged by withdrawing drill casing or auger sections. With the multi-level system, cables are encased in the PVC pipe and are much less likely to be twisted or damaged.