Abstract
Mineral temporary capping systems of landfills are required to accomplish the long-term coverage prerequisites or to use them as a basis layer prior to later permanent sealing. Such a capping system for a municipal waste landfill in Rastorf (Northern Germany) was developed and tested for its sealing capability on the basis of observed and simulated water balance components for the period between 2008 and 2015, considering observed local weather data and complemented by the Hydraulic Evaluation of Landfill Performance (HELP 3.95 D) model. The modeling results of this case study could be improved by the correction of previously used global solar radiation data due to the consideration of exposure and inclination angle of landfill surface areas. The model could positively be validated by comparing observed and simulated outflow (surface runoff and lateral drainage) data with R2 values ranging between 0.95 and 0.99, as well as for the leachate rates with R2 values of 0.78–0.87. The statistical-empirical HELP model was found useful in predicting the leachate generation of a temporary landfill capping system for specific soil and site conditions, even if only a restricted set of observed data was available.
Highlights
IntroductionLandfill capping systems as engineered barriers are purposed to prevent or minimize the contact of precipitation or melting water percolation with the waste body to limit the generation of leachate or gas emissions, which may reach the aquifer system or the atmosphere, respectively [1,2,3]
This study presents a practical example to show that the Hydraulic Evaluation of Landfill Performance (HELP) model is useful to solve scientific issues with regard to the water balance of landfill capping systems
Sensitivity analysis was used to estimate the effects of changing input quantities
Summary
Landfill capping systems as engineered barriers are purposed to prevent or minimize the contact of precipitation or melting water percolation with the waste body to limit the generation of leachate or gas emissions, which may reach the aquifer system or the atmosphere, respectively [1,2,3]. Semipermeable temporary capping systems (i.e., Rastorf landfill) enable a specific ‘shutdown’ of the bioreactor by a controlled infiltration of precipitation water into the waste body (2.0 × 109 kg of municipal waste) and allow biogas extraction during phases of waste-body settlement [7]. After the consolidation of the waste body, the temporary cover can be replaced by a long-term sealing system that meets statutory requirements [8]. In order to lower these additional financial costs, it is possible and advisable to include the well-functioning temporary capping system layers in the final one, which may even increase or maintain long-term impermeability
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
