The Testing Laboratory Directorate (TLD) is accredited to perform testing of over 70 physical, mechanical and chemical characteristics of soil samples.
The characteristics, which give information about the quality of the soil for agri-еnvironmental and agricultural purposes (humus, nitrogen, sulfur and moving forms of some elements), are determined.
The determination of moisture, dry matter and loss on ignition is performed using weight methods.
The element content in soil samples is determined in accordance with standardized methods, after aqua regia digestion. The measuring of the solutions obtained is done using ICP-AES, while the mercury content is determined using the cold mercury vapor method and atomic fluorescence.
The gold content is determined after aqua regia digestion, extraction with an organic solvent and atomic-absorption analysis.
The content of total extractable substances and petroleum products (nonpolar hydrocarbons С10–С40) in soils is determined using a gas chromatograph, equipped with flame ionization detector.The organic contaminants content – 16 polycyclic aromatic hydrocarbons (PAH) and over 80 pesticides, is determined with a gas chromatograph with a mass spectrometry detector.
The type of the tested characteristics complies with the requirements of the following normative regulations:

• Наредба № 3 от 1 август 2008 г.Ordinance No 3 from August 1, 2008 regarding the norms for acceptable content of harmful substances in soils;
• Ordinance for the order and manner of sludge utilization from the purification of waste waters through their use in agriculture.

At TLD we perform diagnostics of mineral composition of soils (qualitative and quantitative X-ray diffraction analysis), as well as their granulometric characteristic (using classical methods and laser diffraction), and these activities are beyond TLD’s scope of accreditation.