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Static water level calculations can be made using static pressure and depth data from response testing, as well as pre- and post-test response data measured at the top of the reference tube at zero flow. Since the HPT system uses an absolute pressure transducer to measure in-situ pressures, pre- and post-test data must be changed to reference atmospheric pressure.

(Pre-test + Post-test) / 2 - 0.433 = Atmospheric Pressure in psi

Atmospheric pressure can now be subtracted from the static pressure to obtain the amount of water pressure measured at the down hole pressure transducer.

(Measured Static Pressure - Atmospheric Pressure) = True Static Pressure in psi

Now convert the True Static Pressure in psi to feet of water by multiplying by 2.31.

True Static Pressure in psi × 2.31 = True Static Pressure in feet of water

Subtract the depth of probe screen from the True Static Pressure in feet of water to get depth to static water level.

Depth in Feet - True Static Pressure in feet of water = Static Water Level in feet below ground