In the case of the conversion of the air base in Erding, two-thirds of the construction waste could be recycled and thus reused. There would be room for this, according to the results of an investigation.
Erding – These are figures that illustrate the enormous dimension of the imminent conversion of Erding Air Base: On the 350-hectare area, which will be used for military purposes by the end of 2024 and on which a new district for up to 6500 citizens will be built in the next few decades, a good 1.5 million tons of construction waste will fall during the demolition of the buildings and also the underground structures, asphalt and excavated material. The good news – also for reasons of sustainability – is that around 950,000 tonnes of it could be processed and reused. These figures were announced by Thomas Rojas Sonderegger on Tuesday evening in the Urban Development Committee.
The young man is studying civil engineering at the Technical University of Munich, dedicated his master's thesis to the topic and developed a recycling strategy using the example of air bases. He had already presented key data in mid-December as part of the lecture series "Rundflug Fliegerhorst" at the Museum Erding (we reported).
And he had a vivid example ready so that one can better imagine the gigantic volume of construction waste. With the huge mountain of material, Erding's entire old town could be covered with a four-meter-high layer, he said in the SEA. Of this amount, 600,000 tonnes are probably contaminated with pollutants and must be disposed of separately. Sonderegger gave this estimate after a comparison with other barracks. However, two-thirds, i.e. 950,000 tonnes, could be temporarily stored and recycled on the site itself, for example in the existing aircraft shelters, Sonderegger said. Such a plant included a hall with a mixing plant and silos, storage boxes for raw and finished products, but also crushing and screening plants.
A rubble recycling plant envisaged by the city north of the Wiweb because of its proximity to the air base could also be used for this purpose. The way there for the trucks is short and does not lead through the city, provided that the northern connection is realized. According to Sonderegger's calculations, on-site processing saves 70,000 truck trips to other landfills and almost 1.7 million kilometers. North of the Wiweb, there is already gravel quarrying and asphalt mixing plants.
Reprocessing would have consequences for urban land use planning, "because the material remains on site," says Sonderegger. For example, selective dismantling would have to be carried out in order to preserve high-quality construction waste. Depending on its compressive strength, recycled concrete can now also be used for load-bearing components.
The city councillors listened with interest to Sonderegger's lecture. Mayor Max Götz (CSU) explained in response to a question from Burkhard Köppen (CSU) that the city could once contractually fix the use of RC concrete with the investors. Recycling is also becoming increasingly popular with concrete manufacturers due to the scarcity of natural resources and rising landfill costs.
Before it becomes so concrete, negotiations with the Federal Institute for Real Estate (Bima) are pending, from which the city wants to acquire the entire air base area. Preliminary investigations should help to put the city in a good negotiating position. "These comparative values are important when the Bima mentions cost estimates of what the demolition of an existing building costs," explained urban developer Christian Famira-Parcsetich. Sonderegger even examined the excavation quantities for the station. However, he had to work with many assumptions, "because we don't know so many details yet".
As for the amount of material contaminated with pollutants such as asbestos, Götz is not very optimistic. He referred to the underground rubble caused by bunkers and the apron of the aircraft hangars. Ultimately, there is always a risk for the city "that we will experience a surprise during the in-depth investigations in the buildings".
Even though the city does not yet own the air base area, the preparatory work for the conversion has been going on for years. This also includes feasibility studies, for example on rainwater management – SEA has just awarded the contract to the Landshut office SKI for a good 31,000 euros – and on mobility. After all, the focus in the new district will no longer be on individual transport by car, but on bicycles, sharing services and public transport. The urban planning for part of the area, for example, envisages keeping the public street space free of parked cars (we reported). For example, vehicles are to be parked exclusively in above-ground neighbourhood garages.
