This paper presents a bench-scale study of bioremediation of soil contaminated with maleic anhydride. A quantity of 300 kg of contaminated soil was collected from a petrochemical plant in Malaysia and divided into three portions in order to investigate the effects of nutrient addition as well as mechanical aeration on the biodegradation rate of the contaminants. Online parameters measured included moisture content, redox potential, temperature and pH. The highest first-order biodegradation rate constant was determined to be 6.658 day -1 for soil pile with addition of nutrients and mechanical aeration.