DEVELOPMENT OF DRAINAGE WATER QUALITY FROM LANDFILL COVERS BUILT WITH ASHES AND SEWAGE SLUDGE

SUMMARY: An alternative to virgin and artificial materials in landfill cover can be various types of waste materials like ashes and sewage sludge. From the environmental point of view, the most interesting question to study is the quality of the drainage water generated above the liner in landfill cover built with waste materials. Thus, the main aim of this paper is the evaluation of drainage water quality and time required for its treatment. Results from a full scale test, physical models and a column test were used in the evaluation of the drainage water quality development. The main contaminants identified in drainage water were N-tot, As, Cu, Cd, Pb, Zn and Ni. The laboratory tests showed higher concentrations of N-tot, NH4-N, TOC, As and Pb, but lower values of Cl, Zn, Ba and Ni in comparison with drainage water from the field. It was probably a result of different factors that may have influence on leaching but interactions of the protection layer with the vegetation layer and the liner surface are expected to influence the results from the field. According to results from the laboratory experiments, drainage water will probably need treatment for at least two-three decades after covering. 1