Sealing the quarry wall at the Borgholzhausen landfill site, Germany
The district of Gütersloh needed to create a local disposal zone for construction debris and soils to minimize the impact of the waste transport process and the associated heavy vehicles on the area. Landfill operator GEG (Gesellschaft zur Entsorgung von Abfällen Kreis Gütersloh mbH, Germany) manages the Borgholzhausen landfill for inert waste. The site is a piggyback landfill on a previously closed landfill body. In a resource-saving solution, the area of the new landfill takes volume from an abandoned limestone quarry. The back of the landfill is formed by the vertical excavation front of the quarry to minimise and optimise land use. The surface of the vertical front is rough and uneven due to the irregular weathering of the layered rock.
Under such challenging boundary conditions, special engineering measures are required to ensure that the base sealing of the new landfill body meets the high standards for sealing systems for landfills in Germany even at the vertical face of the quarry wall, thus preventing the release of landfill leachate. The construction and quality assurance measures were planned by Asmus + Prabucki Ingenieure Beratungsgesellschaft mbH.
A central element for lining the vertical quarry wall is a successive construction progress of the sealing system. It is not possible to install a mineral base seal vertically on the steep face, as required by the Landfill Ordinance for base seals. This raised questions of stability. To resolve them, the team installed the mineral liner in single steps in a stable, compacted trapezoidal cubature, each 4m high, with an inclination of 1:1.5 successively with the waste body.