It had been researched about the degradations of waste oil by using the synergy of bacterial consortium with lamtoro gung {Leucaena leuchepala) method in field scale. Contaminated soil by petroleum the concentration condition sludge were set up 7.5%. Bioremediation process had been done in 12 weeks and it were treated by adding fresh soil, bulking agent, and nutrition with ratio N/P/K was 10 : …