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Land development causes stress on the surrounding environment. Natural resources that we cannot replace are utilized in the extensive development. Land development and transport cause a large part of emissions in Stockholm. By planning with sustainable development the negative impacts can be limited.

What impacts can landfill activities have on the environment? In 2008 a landfill southeast of Stockholm was covered as a part of the city’s environmental program. The landfill was covered with approximately 113 500 metric tons of mixed aggregates. All aggregates were secondary materials originating from contemporary land development projects in Stockholm.

The landfill coverage was studied with respect to energy use and emissions. A hypothetical case was also created, in which all landfill aggregates were produced from virgin material. The study was hence separated into two systems: one with secondary aggregates, and one with virgin materials. Evaluation of environmental impacts in each system was conducted with life cycle assessment methodology.

Results showed that the City of Stockholm kept emissions of pollutants at lower levels by using secondary materials in the landfill coverage. Greenhouse gas emissions were reduced by 48% when secondary aggregates were used as compared to usage of virgin material. Production from virgin material resulted in high energy consumption and consequentially high emissions. Production of aggregates from virgin materials contributed with 25% total CO₂-emissions, and 44% of energy consumption.

Emissions were kept low through minimized vehicle kilometers. By utilizing secondary materials 69% of the energy consumption was spared. Valuable natural resources of virgin materials were conserved.