A SIMPLE METHOD FOR MEASURING THE VERTICALITY OF SMALL-DIAMETER DRIVEN WELLS

The presence of stones, solid waste, and other obstructions can deflec t small-diameter driven wells during installation, leading to deviatio ns of the well from its intended position. could lead to erroneous res ults, especially for measurements of ground water levels by water leve l meters. A simple method was developed to measure deviations from the intended positions of well screens and determine correction factors r equired for proper measurement of ground water levels in nonvertical w ells. The method is based upon measurement of the hydrostatic pressure in the bottom of a water column, which is established in the well tub e. The method was used to correct water level measurement in wells dri ven through a landfill site. Errors of up to 27 cm in water level were observed at the landfill site. The correction of the water level meas urements had a significant effect on estimated local ground water flow directions.