Soil contamination testing

Why testing matters before you buy

Obligations under environmental law already arise at the design stage of a project — an industrial building, a treatment plant or a well. Under the Environmental Protection Law, the owner of the land is the party primarily responsible for removing contamination on the site of the investment. Buying a plot without testing therefore means taking on an unknown liability along with the title.

Remediation is often a very costly undertaking and, without accredited testing carried out under the 2016 regulation, it is difficult to prove that a previous owner caused the contamination. Testing before the transaction is the only way to document the condition of the ground at the moment of purchase.

What we test

• ground conditions for the foundations of buildings — residential blocks, warehouses and production halls,
• ground and water conditions together with contamination testing,
• laboratory analysis of soil and water samples, primarily for petroleum substances and heavy metals such as mercury, lead, cadmium, zinc and arsenic,
• soil pH, relevant for agricultural and horticultural projects and for the choice of foundation insulation.

Drilling and sampling are carried out in accordance with the Regulation of the Minister of the Environment of 1 September 2016 on the assessment of land surface contamination (Journal of Laws 2016, item 1395).

Geotechnical survey versus contamination testing

These are two different things. A geotechnical survey establishes the geological profile and the groundwater level, so that the building can be designed correctly — foundations, insulation, wall types and rainwater drainage. It can reveal peat and other organic deposits, plastic sandy clays or made ground, none of which support foundations well.

Contamination testing goes further: samples of soil and water are analysed in a laboratory for hazardous substances. It is carried out mainly for larger projects — production halls, filling stations, housing estates — and on post-industrial land, where the risk is many times higher. If contamination is found, the developer must clean the site before construction continues, even if it did not cause the problem.

Is it mandatory?

Since 19 September 2020, following the amendment to the Construction Law, every architectural and construction design must include a geotechnical opinion — including for single-family houses. Larger projects are assigned by the designer to geotechnical category II or III, which means laboratory analysis of soil and groundwater samples is required before works start. Category I applies to single-family houses and smaller ancillary buildings.

How much does it cost?

The price depends on the size of the plot and the complexity of the analysis. It is largely the cost of the boreholes: PLN 100–150 per running metre, with at least three boreholes 3–5 m deep as standard — so roughly PLN 1,000 to 2,500 for a geotechnical opinion including the description and the geotechnical cross-section.

The price rises when the scope covers compaction testing or laboratory analysis for contaminants, and when deeper boreholes are needed — for example for wells or for more complex hydrogeological work. Cleaning up what the testing finds is quoted separately as remediation.

How the work is carried out

Geotechnical surveys may be performed only by geological companies holding the relevant licences. Our specialists first review the available material, such as ground maps, and then carry out the boreholes — usually to about 2 m below the planned foundation level, so 3–5 m in practice. Core samplers, also known as window samplers, are used to establish the geological profile.

Water is sampled from a borehole cased with plastic pipe and sealed in cylinders made of chemically non-reactive material; soil is scraped from the drill or sampler and placed in glass containers. Each sample is described with the borehole number, the depth it was taken from and the analysis it is intended for, and then delivered to a specialist laboratory.

Why Vicesima

We have been among the leading Polish companies in the environmental sector for well over a decade. We carry out soil and groundwater testing across Poland and in neighbouring countries, and we work with accredited partner laboratories that analyse samples reliably and on time. We have completed more than two thousand geotechnical surveys, including work agreed with Shell, and we specialise in difficult sites with potential contamination.

Where testing reveals serious contamination, we can also carry out the remediation — the only effective way to make the land usable for construction again.