Bongaigaon Refinery, Assam in India is in the business of refining crude oil since 1974. The effluent of the refinery drains into the Tunia river, which flows through agricultural lands. The present study investigates the pollution level of the Tunia river water as well as the soil of the nearby agricultural lands. Water samples were analyzed for pH, EC, TDS, TSS, SAR, sulphate, phosphate and heavy metals Cr, Ni, Mn, Zn, & Cu. Soil samples were analyzed for pH, EC, Na+, K+, sulphate, phosphate and Cr, Ni,Mn, Zn, and Cu. Contamination levels of Cr, Ni,Mn and Cu in the river water were under the permissible limit set by FEPA, except Zn, which was in alarming level.However, the values for Cr,Mn and Cuweremuch higher than the limit set by FAO. The study also reveals the enrichment of Cr, Mn, Ni and Cu in the agricultural soil irrigated by the Tunia river water.