Abstract: A spray rinsing apparatus carried by a mobile chemical spray apparatus which includes a pair of flexible rinse water storage vessels shaped and adapted to be supported in draped position from the top of a chemical reservoir tank and the sides of the tank. A gasoline engine driven pump is connected to withdraw rinse water from the flexible vessels. The rinse water is pumped at high pressure into a built-in spray head assembly inside the chemical tank and also through a jet spray gun to clean the exterior of the chemical spray apparatus. The system is capable of confining the chemical spray chemicals to the application job site and thus avoid contamination anywhere else.