Terex foamed asphalt system allows producers to mix water and hot liquid asphalt (AC) in the exclusive expansion chamber, which eliminates the need for additives, according to Terex Roadbuilding. System consists of an expansion chamber and a programmable logic control (PLC)skid package. Once the hot AC and water combine in the chamber, the foamed asphalt is injected into the drum. For field installations, the PLC unit comes complete in a water skid package. It interacts with plant control to meter water, and it includes a 220-gallon tank.