Chemical composition of landfill leachate in a karst area with a Mediterranean climate (Marbella, southern Spain)

Between March 1994 and April 1997, the physical and chemical parameters and chemical composition of the urban solid waste leachate of the Marbella lan dfill (southern Spain) were determined. The data obtained show an ammonium and sodium chloride and bicarbonate type, a pH>7 and high mineralization, e ffectively described by the following parameters: Na+, K+, NH4+, Cl- and al kalinity. The chemical composition depends on the rainfall: in dry years, t he mineralization and component concentrations have values as much as doubl e those found in normal rainfall years. After storm events, a major and rap id dilution (within several hours) is seen in the leachate.