Example of an Instruction Manual


DRIVING A WELLPOINT


Roger E. Machmeier

1.0 Introduction

A wellpoint or drive point is a pipe with wall openings large enough to allow water to enter and amall enough to keep water-bearing formation in place. Wellpoints suitable for hand driving are available in sizes from 1 1/4 to 2 inches in diameter and from 19 inches to 3 feet long. The size of openings in the wellpoint is determined by the relative grain size of the material in the waterbearing formation. Some of the finest grains adjacent to the wellpoint should be removed by pumping to make the well more productive (see figure 1). However, a wellpoint should not be expected to yield large quantities of water.

2.0 Why Wellpoints are Used

It may be desirable to develop a water supply for sprinkling lawns, gardens, etc. An economical supply can often be obtained from a shallow aquifer (water-bearing formation) through a wellpoint. The water table should be high, preferably within 10 feet and no farther than 15 feet underground. The wellpoint must be driven deep enough to penetrate a water-bearing formation below the water table, but it should not exceed 25 feet in depth.

Shallow water tables are susceptible to pollution. Drain fields, dry wells, animal wastes, heavy fertilizer applications, etc. can contaminate a shallow water table. Recharge is usually from rainfall, falling directly above and percolating downward to the water table. As the water moves downward it may carry contaminants. Thus, extreme care and periodic testing are necessary if the water is used for drinking.

3.0 Materials Needed

The following materials are needed: wellpoint, riser pipe (in 5- or 6- foot lengths, with 6-inch nipple), couplings, drive cap, and pipe thread compound.

4.0 Tools Needed

A posthole digger or soil auger, sledge hammer, carpenter's level or plumb bob, and pipe wrenches are needed for hand-driving a wellpoint.

5.0 Installation Method

It is usually a sound policy to have a reliable well driller develop a sanitary water supply for a home. Water purity and personal health should be the major consideration in developing a domestic water supply.

-from Houp and Pearsall- Reporting Technical Information, Revised by Dale Sullivan