The Al Khoudh landfill in Muscat, Oman, was originally used for different kinds of waste including construction and demolition waste.

It is unknown whether or to what extent the dumpsite also contains waste with potentially negative impact on the environment, or whether landfill gases are generated in the area. Moreover, the catchment area for public and private drinking water wells might be located in the area.

In spite of this uncertainty, private homes are still being built in the area. Muscat Municipality thus engaged COWI to investigate potential risks and to recommend remedial actions on and around the Al Khoud landfill.

Monitoring of soil and groundwater
COWI has conducted field investigations and soil and groundwater monitoring and developed a conceptual modelling for the landfill and its surrounding environment. The latter to assess the risks relating to the future use of the landfill as residential area.

Tasks included project management, risk assessment and proposal for remedial actions including a matrix outlining economic, technical and environmental pros and cons associated with each remedial action.