A system for evacuating sand, paraffin, and other particulate matter from an oil well, while simultaneously lifting the oil to the surface and stimulating its rate of production, comprises a series of transport units attached to an endless belt. The belt is positively driven between a wellhead station at the surface and a downhole module which is self centering within the well casing, thereby avoiding damage and wear to the casing. Preferably, the belt comprises a roller chain which enables the depth and rate of production of the evacuation system to be easily adjusted. The transport units are replaceably mounted on the belt and are specially designed to agitate and accumulate the particulate member in the oil well.