Abstract: This disclosure relates to an improved solar water purification system and process wherein the evaporating, condensing and distillate collecting chambers are located underground to assist in the evaporation and condensation process. The system includes three computer controlled preheaters which are constantly monitored to determine the temperature of the load therein. The cycling and recycling of the load relative to the load tank and the three preheaters is controlled by the computer for optimum system efficiency. One of the three preheaters is located underground, while a second preheater is located externally as a solar preheater and the third preheater is an outside gas, oil or waste heat fired preheater. In addition to producing pure water through the evaporation process, there is disclosed a system and process whereby various contaminants may be captured for further processing, storage and exploitation.