Plane de-icing agents contribute to soil and groundwater contamination at airports

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Spring has arrived in Europe with mild temperatures and sunshine. Where just a few weeks ago the ground was frozen and partly covered in snow and ice, it is now thawing. This doesn't only have an impact on the flora and fauna. Thawing results in soil and the groundwater at airports being impacted by chemicals, which are contained in melt water. The reason: Airports have to use de-icing agents during the winter, which end up on unpaved areas and infiltrate into the soils during snowmelt.

Spring has arrived in Europe with mild temperatures and sunshine. Where just a few weeks ago the ground was frozen and partly covered in snow and ice, it is now thawing. This doesn't only have an impact on the flora and fauna. Thawing results in soil and the groundwater at airports being impacted by chemicals, which are contained in melt water. The reason: Airports have to use de-icing agents during the winter, which end up on unpaved areas and infiltrate into the soils during snowmelt.

"Admittedly, airport operators in EU-countries are compelled to sustain a good condition of the groundwater or at least to avoid detrimental concentrations of pollutants in the groundwater," says PD Dr. Markus Wehrer from the Friedrich Schiller University Jena (Germany). "However, it is common practice that along the runways huge amounts of de-icing fluids infiltrate into the ground," the Hydrogeologist adds. It does indeed make sense to use the natural self cleaning capacities of the soil. However, the de-icing chemicals have a negative impact on groundwater quality and the functions of the soil. This was shown in a new study of a team of researchers around Prof. Dr. Kai Uwe Totsche at the Jena Chair of Hydrogeology.

In the science magazine "Environmental Science and Pollution Research" the scientists of the University Jena wrote that chemicals like propylene glycol und potassium formate are being degraded by micro-organisms living in the soil and therefore don't get into the groundwater - at least not straight away (DOI: 10.1007/s11356-014-3506-3). "On the other hand, heavy pollution through these substances leads to a dramatic decrease of oxygen content in soils and groundwater," Heidi Lissner, the first author of the study explains: This is because the microbes use oxygen to degrade the pollutants. "The more of these substances they have to metabolize, the more oxygen they use for this," says the geoscientist, who developed the results - which are now published in the study - within the framework of her PhD thesis. As a consequence iron and manganese oxides, which stabilize the intergranular cement of the structure of the soil, dissolve.

Continue reading at Friedrich Schiller University Jena.

Deicing image via Shutterstock.