Virrat (Finland)

The pilot site of Populus Group Oy is located in Virrat, Finland.

​The pilot site is located within the industrial area of the municipality of Virrat in Pirkanmaa lake district. The site was previously used for the construction and storage of vehicles. All industrial actions in the area have been ended.

The site is situated in a small city. The city plan classifies the area to be used for industrial and business activities in the future. City plan defines that 60 % of the area can be used for industrial activities. The rest can be used for business activities. It is also possible to live in the area. The activities are not allowed to threaten the quality or amount of ground water. The site is situated next to an important (class I) ground water area.

Elevated concentrations of heavy and medium fractions of oil hydrocarbons, as well as mercury and lead have been detected in soil. Therefore, the site is classified as contaminated/decayed.

The primary contaminants are oil hydrocarbons that are elevated on an area of 1 400 m2. The hydrocarbons occur at 0 – 2.7 m depth and the amount of spoiled soil is estimated to be 2 850 m³ (solid cubic metre) (ca. 6 400 tons). The average oil hydrocarbon concentration in spoiled soil is estimated to be 1 500 mg/kg, when the total amount of oil in the area is ca. 9 600 kg (ca. 10 700 liters). Elevated diesel oil (max. 3 950 mg/kg) and lubrication oil (max. 6 360 mg/kg) concentrations have also been detected. Highest concentrations have been observed in surface samples. One sampling point had an elevated oil hydrocarbon concentration also at the depth of 1.7 – 2.7 m. Elevated heavy metal concentrations (6.4 mg/kg Hg and 490 mg/kg Pb) occur in a few small patches in the surface soil (0 – 0.3 m). Elevated heavy metal concentrations have not been detected in ground water.

Remediation efforts using phytoremediation with trees and their associated microbes have been started, after two truckloads of soil with extremely high concentrations of heavy metals were excavated. Clonal seedlings of hybrid aspen and European aspen have been planted in October 2017. The total area for phytoremediation is ca. 1 500 m2.