Portable system from Riveer Environmental is designed to prevent dust and drag-off. When a vehicle is driven onto the wheel wash system, an electronic eye triggers the system to start cleaning. Two 150-gallon per minute pumps flush mud and rocks off the tires and undercarriage. The system is capable of handing 30 to 60 vehicles per hour. Sludge and rocks washed off the tires drain into a center trough where a conveyor removes the debris.