Besides strict requirements for landfills the EU has also established criteria and procedures for the acceptance of waste delivered to landfills. Hazardous waste landflilled must meet the relevant waste acceptance criteria, which, besides standards for physical stability, consist of quantitative limits for leachable substances and organic matter. Evaluated testing methods - batch tests and a percolation test - were used ill this investigation to study the leaching behaviour of oil shale semicoke. The results obtained indicate that none of the leaching limit values for inorganic components were exceeded ill the analysed semicoke samples. The influence of recarbonation oh the leachability of different components from semicoke was also studied.