A study on the landfill leachate and its impact on the groundwater quality of the greater area

Characterisation of the leachate originating from the Ano Liosia landfill (situated in Attica region, Greece) as well as assessment on the quality of the local aquifer were carried out. The experimental results showed that most of the parameters examined in the leachate samples such as colour, conductivity, TS, COD, NH₃–N, PO₄–P, SO₄ ^2–, Cl^–, K⁺, Fe and Pb were found in high levels. The organic load was quite high since the COD concentrations were in the range of 3250–6125mgL^–1. In addition, the low BOD/COD ratio (0.096–0.195), confirmed that the majority of this organic matter is not easily biodegradable. The groundwater near the landfill site was characterised as not potable and not suitable for irrigation water, since most of the physical and chemical parameters examined – such as colour, conductivity, DS, hardness, Cl^–, NH₃–N, COD, K⁺, Na⁺, Ca²⁺, Fe, Ni and Pb exceeded the permissible limits given by EE, EPA and the Greek Ministry of Agriculture. Furthermore, this study presents the application of the hydrologic evaluation of landfill performance (HELP) model for the determination of the yearly leakage from the base of the landfill after the final capping.