Spray equipment requires periodic cleaning and rinsing to keep vital components in good working condition and when switching from one pesticide to another. Improper management of rinsate has great potential for contaminating surface and ground water. The best way to eliminate this problem is to perform all interior and exterior rinsing in the field immediately following the application. Equipment may also be rinsed at a modern pesticide mixing and loading facility equipped with a concrete rinse pad and rinsate-collection pit. However, disposal of the rinsate collected in the pit could become a major problem. This is why it is important to reduce the amount of rinsate to a minimum.
If possible, reuse the rinsate when preparing the next batch of tank mixture. Make sure all the dirt and debris in the rinsate are filtered out before adding the rinsate to the spray tank. The small amount of solids left in the collection pit should be dried and taken to a hazardous waste disposal site or spread evenly over a large part of the field. Information on constructing a rinse pad and pesticide-storage facility is available at your local county Extension office.