Remediation measures
Section 2(7) of the Bundes-Bodenschutzgesetz (BBodSchG) law defines the term “remediation measures” as follows:
- Measures aimed at pollutant elimination or mitigation (decontamination measures)
- Measures that aim to prevent or mitigate pollutant propagation over the long term, without actually cleaning up the pollution (safety measures)
- Measure that aim to eliminate or mitigate deleterious changes in the physical, chemical or biological properties of the soil.
According to section 5(4) of the BbodSchG law, sites are to be cleaned up in cases where deleterious soil changes or site contamination have occurred after 1 March 1999, insofar as such measures are reasonable in light of the relevant site’s preexisting contamination.
The law requires the authorizing body to determine which measures are necessary and in keeping with the principle of proportionality, in order to comply with statutory hazard prevention requirements. This proportionality assessment is part of the remediation study. If the relevant remediation measures are disproportionate for a given site, protective and mitigating measures can be used instead. Natural pollutant mitigation mechanisms should also be factored into official decisions concerning cleanup measures or protective and limiting measures.
The cost and effort entailed by the various possible measures, including follow-up measures, as well as for any necessary monitoring of a given cleaned up site, can vary considerably. Thanks to the availability of a network of expert engineering providers and the related clean-up infrastructure, a host of solutions and technical methods are available. However, this does not exclude the possibility that (a) no reasonably priced cleanup solution is available; (b) the cleanup cost may be unreasonable; or (c) there might be opposition to the use of innovative techniques or management concepts.
Oftentimes, a constellation of measures is carried out using mobile and semi-mobile cleanup equipment modules. Complex management concepts that encompass monitoring solutions have also proven successful.
The hazard-prevention measure selection process should take the environmental impact of the envisaged measures into account, as well as the socioeconomic dimensions of site cleanup and land recycling. It is often the case that a combination of decontamination and construction measures for land reuse purposes is more sustainable than conventional excavation. Moreover, soil and groundwater cleanup efficiency can be optimized through the development of more complex, innovative cleanup strategies.
Geotextiles are used to protect uncontaminated areas and to secure slopes.
The application of mobile earthworks technique on installation sites has proven successful. Thereby sources of contamination as well as foundations on old sites can be excavated precisely.
The investigation of the situation of groundwater (location, flow direction, kind, pollutant concentration) is a crucial requirement to select appropriate remediation processes.
Contaminated groundwater on old sites requires a remediation, mostly through mobile or semi-mobile plants, as shown in this picture.
Semi-mobile thermal soil treatment facility
A large hole drilling machine in action on a remediation site. Contaminated soil is extracted, procured with a soil treatment or deposited though the drilling method. An infilling of the drilling hole with unloaded material takes place.
Special work safety precautions need to be made when working in contaminated areas, e.g. wearing personal protective equipment as you can see in this picture.
Steel sheet piles prevent the proliferation of contaminations. These construction forms are used as so-called backup procedures.
The application of mobile and high-definition exploration processes on-site ('Direct Push' in this case) is economically and temporal advantageous with mainly excellent detection results.
On-site analytics require extensive and complex analysis technologies and software-support.