City of Lappeenranta

Sampling year: 2018

Sample media: topsoil (0–10 cm): aqua regia extractable concentrations from the <2 mm grain-size fraction

Land use: various land use classes in the city centre

The Geological Survey of Finland (GTK) has investigated geochemical baseline concentrations in the city of Lappeenranta. Altogether, 219 topsoil samples were collected from the city centre in 2018. The sample sites represented various land uses in urban areas. Samples were collected from 10-cm-deep pits. Concentrations for 40 elements were analysed after aqua regia extraction. In addition to that, carbon content and pH value were determined from all samples

The concentrations of arsenic exceed the threshold value 5 mg As/kg (Decree VNa 214/2007) in four samples. The concentrations of lead exceed the threshold value in three samples and the concentration of Co in one sample.

The threshold values given in the Decree (VNa 214/2007) can be applied for arsenic and all metals in Lappeenranta, while the upper limit of baseline variation was lower than the threshold value for all elements. Upper limit of baseline variation was calculated for several elements that are not included in the Decree.

Report

Tarvainen, T., Eklund, M. & Kananoja, T. 2018. Lappeenrannan taajama-alueiden maaperän taustapitoisuudet. Geologian tutkimuskeskus. Työraportti 82/2018. 32 s. https://tupa.gtk.fi/raportti/arkisto/82_2018.pdf

Upper recommended limits of baseline variation (SSTP) of selected elements in soils of City of Lappeenranta and the threshold values (Decree 214/2007).