JAM Drill Rig Technical Information

Each water well is drilled as follows (down-the-hole technique in a fractured aquifer):

The drill rig is set up on the spot selected by the geophysicist following the siting with geophysical equipment. Drilling starts with a diameter of 10", followed by the insertion of 8 ½" temporary casing, to prevent the overburden from collapse. Drilling continues with a diameter of 8 ½", until such time that non-collapsible formation is encountered. Drilling continues for three meters into hard rock, thereafter the drill rods are pulled out and permanent casing (6 ½") is inserted.

Depending on whether a water strike occurred within this formation, either plain or perforated casing is installed. Perforated casing allows water to flow from the water strike in the formation into the water well. Thereafter, drilling continues to target depth with a drill bit diameter of 6 ½". This part of the hole remains uncased as collapse of the formation does usually not occur.

If perforated casing was installed in the hole, fine-grained filter pack will be inserted into the annulus.

A sanitary seal, i.e. cement/ bentonite (industrially produced clay) slurry is inserted from on top of the filter pack, from a depth of 5m below surface to surface level. This seal will prevent groundwater contamination caused by faecal or other pollutants.

Finally, the casing is capped until such time that test-pumping and geochemical analysis of the water takes place. A cement collar is cast around the casing.

The process is technically difficult but the heart and the motivation behind the project is very simple and pure. If people do not have access to safe, clean water they will continue to suffer from water-borne diseases.

JAM aims to play its part in solving this huge challenge that plagues Africa and many other countries around the world.