Remediation of contaminated sites 

In recent years, the number of remediation methods available has increased considerably. This gives new possibilities for site clean-up whilst creating greater demands of the consultant.

Remedial actions are implemented partly to ensure a reasonable land-use and partly to protect groundwater. In the optimal solution both technical and economical aspects are incorporated.

Traditional remediation techniques such as excavation and remedial groundwater abstraction can, with advantage, be used to avert risk from many types of pollutants. In other situations an advanced technology approach to remediation will be environmentally and economically more advantageous. In each case we determine, in cooperation with our clients, which approach is best.

In situ remediation

COWI has worked with many different types of advanced in situ techniques for many years. The methods we employ can be single methods or combinations of methods. Depending on local conditions on the contaminated site, the methods can include soil ventilation like for example; vacuum extraction, bio-ventilation, air-sparging and bio-sparging.

Effective remediation of chlorinated solvents can be achieved with chemical oxidation using potassium permanganate.

COWI has test equipment and laboratory facilities at its disposal that can be used to determine the remediation method and to form the basis for design of the projects.

COWI's expert consulting services include:

• Excavation of contaminated soil
• Abstraction solutions (pump and treat)
• Test to ensure the correct basis for design of remedial solutions
• Advanced in situ remedial solutions