Kontamination von Haufwerk durch Sprengmittel und Dieselmotoremissionen

In times of climate change, resource scarcity, circular economy, and measures to reduce CO₂ emissions, the use of excavated tunnel material as aggregate or alternative construction materials on or off the construction site is an important topic. However, the use of excavated materials is made more difficult by their legal definition as waste products. This requires a comprehensive analysis in accordance with the Landfill Ordinance 2008 and the Federal Waste Management Plan 2023, which also prescribes the testing of the parameters ammonium (NH₄⁺), nitrate (NO₃⁻), and nitrite (NO₂⁻). Contamination of the excavated material by these substances was previously attributed exclusively to blasting agents and their conversion products, which are deposited on the heap from the blasting swaths. However, more recent findings suggest that diesel engine emissions from the construction equipment used underground are also a major cause of this contamination. In order to shed more light on this issue, samples from construction sites with conventional tunnelling as well as underground mining were taken and analyzed.