Different methods of drilling a borehole
Important to note the different drilling methods used by Helderberg Water Drilling and how this fit into you specific requirement.
Water jet blasting well drilling
This method of drilling is only suitable for shallow water wells (wellpoints) where the water table is above 7 meters and the ground conditions allow water jet blasting. (Like sand, light gravel, weathered granite and certain combinations of sand and clay. (Most economical)
Mud circulation rotation drilling
Mud rotation drilling is used where the geological conditions does not allow wellpoint blasting but it is believed that suitable water might be found for a shallow water well.
Mud rotation drilling is also utilised where the ground conditions does not allow down the hole hammer drilling like in deep sand or clay.
This method of drilling require more time and a much larger drilling site space. (Generally cheaper than DHH drilling if the hole is not too deep a geological conditions is suitable.)
Down the hole hammer drilling / DTH (conventional)
This is the most common method used for water well drilling. The drilling steel used is tipped with a drill bit that is mounted on a high pressure air driven hammer. This drill string is than advanced into the ground at slow to medium rotation to create a borehole. The cutting is blown out of the hole by the same air used to drive the hammer. (Standard borehole cost.)
Down the hole hammer drilling / DTH (Overburden or casing advance drilling)
This method of drilling is in most aspect the same as conventional DHH drilling except that the borehole casing is advanced into the hole with the drill bit. Although this method of drilling is significantly more costly it allows us to drill is geological formations and positions where other drill method is not possible. SYMMETRIX or ODEX system is most common overburden systems used. (Costly but sometimes the only way possible.)