Lubna landfill

Lubna landfill1 IntroductionMunicipal wastes from Warsaw are utilised at several places, among others at the Lubna site (Fig.1), an old large landfill, located nearby residential areas. The construction of the Lubna landfill hasnot been sufficient enough with regard to the stability and environmental protection. After havingutilised the landfill for many years, it became necessary to stabilise the landfill slopes and toperform remedial works to prevent pollution of the surrounding groundwater levels.This summary starts with descriptions of the site of the Lubna landfill and the subsoil conditions,followed by investigations of parameters of wastes, including waste morphology analysis, physicaland hydraulic properties, sounding and permeability tests, settlement and lateral movementmeasurements as well as back analysis. The test results were used for water balance evaluationdisplacement prediction, stability analysis and groundwater flow modelling. As it has beenmentioned, remedial works have been performed, including slope reinforcements, construction ofa cut-off wall, a leachate drainage system, a treatment plant, technological roads construction,mineral capping system, as well as ecological remediation with plants and a degassing system.The pollutants transport is controlled by local water monitoring system. In the future the landfillarea will be used for recreation purposes.FIG. 1 View of the western slope of the Lubna landfill2 Site location and descriptionThe Lubna landfill is located at a distance of approximately 35 km to the south of the centre ofWarsaw, in the Góra Kalwaria commune. Forests and idle land surround the site (Fig. 2). Thenearest residential area (Baniocha village) is located at the distance of 08 km to the west (Fig. 3).The site has been used since 1978. At present, it covers an area of approximately 20 ha and it isapproximately 45 m high. In general, the new slopes have an inclination of 1:2.5. Łubna is the onlysanitary landfill where all kinds of municipal wastes from Warsaw are stored. In 1995-1996 slimesfrom the sewage-treatment plant were also disposed there. Every day ca 1000 tons of wastes aresupplied. It will be shut down in 2004.For many years there was no environmental protection system, therefore pollutants could beeasily spread to the surrounding groundwater environment. Since 1996, remediation works havebeen carried out on the landfill. They include a bentonite barrier wall around the landfill(constructed in 1998), a leachate drainage system (constructed in 1997-1998), a treatment plant(under start-up), landfill body forming, berms for improvement of slope stability (underconstruction), degassing (under start-up), a mineral capping system, as well as the coverage ofslopes with compost and plants. The development plan with remedial solutions for the Lubnalandfill is presented in Fig. 4.3