Strategic environmental assessment of alternative sewage sludge management scenarios.

Strategic environmental assessment (SEA) of sewage sludge management in a Danish municipality (Aalborg), with 160,000 inhabitants using alternative methods for aggregation of environmental impacts was performed. The purpose is to demonstrate the use of SEA in relation to sludge management and to improve SEA methodology. Six different scenarios for management of sewage sludge within the Aalborg municipality involving thermal treatment, composting and landfilling of sludge were evaluated.

Linking landfill hydrology and leachate chemical composition at a controlled municipal landfill (Kåstrup, Denmark) using state-space analysis.

Leachate production and composition data for a municipal landfill measured over a 25-year period was used to investigate important processes and parameters. Long-term leachate production could be satisfactorily predicted from a simple top-layer landfill hydrology model while short-term predictions were less accurate, likely due to water storage in the waste. State-space and multiple regression modelling were used to identify relations between different parameters.