In the future, the Barnreuther-Deuerlein quarry will also be allowed to use higher "polluted" material can be dumped and even up to 30 percent construction debris and track ballast. This request of the quarry owner unsettled some Grafenberger, who also fear a danger for the groundwater.
Because even if a sorbent layer is provided, it can withstand the vibrations caused by blasting in the active quarry? If by the new permission from the quarry then a garbage dump becomes? They would like to receive answers to these questions, as the meeting for the establishment of a citizens’ initiative made clear.
Now the management of the quarry has also spoken out and is trying to answer the pressing questions of the people of Grafenberg in a multi-page flyer. "We have thus tried to translate the official German", says Frank Eichler, the operations manager at the Grafenberg site. Instead of groundwater pollution and environmental damage, the opposite should happen with this.
"There is a relief and it minimizes the transport routes of the geogenically polluted material", clarifies Christian Hepler, the graduate geologist of the company Barnreuther-Deuerlein.
The sorption layer consists of quarry-own material that has a certain water permeability and exchange capacity. There is no foil underneath.
"There is a foil only in a landfill that is sealed at the bottom", explains Hepler. And further: "The concern that the sorption layer could be damaged by vibrations is unfounded, since it is a geodynamic layer that is insensitive to deformations."
The maximum of 30 percent construction waste is also not a wish of the quarry owner, but is provided for in the backfilling guidelines. The company could not simply cancel this and act against the regulations of the ministry.
The backfilling guidelines have been "a successful model in Bavaria for almost 20 years, precisely for the protection of groundwater," explains Christian Hepler, who is in charge of the project. First of all, the management makes clear in its letter, which all households received, that the refilling of quarries primarily serves the preventive protection of soil and groundwater with a subsequent reutilization for agriculture and forestry.
In the case of the Grafenberg quarry, the backfilling will also serve the purpose of recultivation and renaturation. "This means that the areas excavated by raw material extraction have to be refilled in order to protect the groundwater from future pollutant inputs. Suitable mineral materials are used for this. These are specified by the authorities and are strictly monitored", explains Frank Eichler.
A landfill, on the other hand, differs quite clearly from it. In technical and legal terms. "Landfilling is the last option for waste management when the waste can no longer be recycled, but only disposed of. This is usually done because of their pollutant load", He pler explains.
The backfilling guideline is an administrative regulation of the State Ministry for the Environment and Consumer Protection and describes exactly which material is suitable for backfilling. The chemical properties of the backfill material are adapted to the existing geology and divided into the categories Z0 to Z2.
Barnreuther-Deuerlein requested to fill part of the quarry with Z1.2 material to be filled in. The other parts are still filled with Z0. Compared to the Z1.2 values, the quarry operator’s explanations list the permissible levels for residential areas, which apply, for example, to arsenic, lead or cadmium. The values permitted in residential areas are almost all higher than those of the backfill material Z1.2.
"Such terms have an unpleasant sound, but are clearly defined", says Hepler. Building rubble would have to be purely mineral, pre-sorted building rubble, for example from a building.
"It may act only sort-pure building rubble such as bricks, concrete and ceramics, which was already freed from pollutant foreign substances such as wood, roofing felt, plaster, mineral wool and likewise Z1.2 must be", He pler explains. "Any excavated soil that contains more than ten percent construction waste – such as the remains of clay pipes – is already considered construction waste. In Bavaria", Eichler says. Strict specifications also apply to the amount of track ballast that can be used. Here is only Z1.1 is permitted, whereby the origin is strictly checked, and checks are also made for pesticides.