Aller et al. (1989) provide a detailed overview of well development and should be consulted

when evaluating well development methods. Overall, the most effective and efficient method

available for inducing flow reversal during well development is the careful use of a properly 

constructed surge block. To be effective, the surge block may need to be lifted and lowered

throughout the well screened interval for several hours, with periodic pumping or bailing of

the fines. Bailers and pumps also have been used successfully to develop wells; however,

depending on the depth of the water, the hydraulic conductivity of the aquifer, and the

diameter of the well, pumping may effectively achieve well development.

The following is a general procedure for developing a well by surging and pumping of

fines:

1.

Record the static water level and total well depth.

2.

Set the pump and record the pumping rate. Pump until turbidity reaches the

desired level as measured using a turbidity meter.

3.

Discontinue pumping and begin surging using a properly designed surge block

and proper surging technique.

4.

Measure and record well depth to determine the amount of fines, and repeat

Step 2. If the well has been properly designed, the amount of pumping

required to achieve the desired turbidity level will be substantially less than the

amount of pumping required during the first pumping cycle.

5.

Repeat surging and pumping until the well yields water of acceptable turbidity

at the beginning of a pumping cycle. A good way to ensure that development

is complete is to shut the pump off during the last anticipated pumping cycle,

leaving the pump in place, and re start it at a later time. The turbidity of the

discharge water should remain low.

Effective and efficient well development is possible only with adequate flow rate

during water withdrawal. Additionally, any fines that have been drawn into the well should

be removed to the greatest degree possible. Therefore, the Agency recommends that one of

the following pumping methods, listed in the order of preference, be used in conjunction with

a properly designed surge block:

1.

Centrifugal pump capable of removing fines if the water level is within

suction lift distance.

2.

Electric submersible pump capable of pumping fines.

November 1992

6 47