The biggest cost drivers are bitumen price volatility, emulsifier package cost, polymers or rubber modifiers, and transport. Operating factors include energy for heating, mill power consumption, labor and QC staffing, maintenance of mills and pumps, and storage related losses. Plants with frequent product switching face higher cleaning cost and off spec risk. Water quality issues can cause batch failures, adding hidden cost. High utilization and stable demand reduce unit cost by spreading fixed costs across more tonnage.