On the territory of the Northern industrial zone of Pavlodar in the area of the industrial wastewater reservoir «Bylkyldak» in some areas of the earth there is soil contamination with mercury, exceeding the MPC for mercury (2.1 mg/kg) by 500 times. The total mass of mercury dispersed in the surface layer of soils is 2.8 tons. The mass of contaminated soil is approximately 208,000 tons. Pollution of the territory is historical. The purpose of the article is to determine the efficiency of chemical binding (immobilization) of mercury in the soil with the Japanese drug Denite® in real field conditions of the territory of mercury contamination in the Northern industrial zone of Pavlodar using an experimental study; to determine the stability of insoluble mercury compounds formed by the preparation at extreme winter and summer temperatures and seasonal fluctuations in open ground. Soil samples were taken for the study at 11 points in the centers of mercury pollution. Laboratory studies were carried out in an accredited analytical laboratory of the Testing Center of JSC Caustic. Soil samples were treated with Denite®, the preparations obtained were stabilized, and water extracts were prepared. The content of mercury in soils, extracts from them, and plants was determined by the atomic absorption method on a RA-915+ spectrometer equipped with RP-91 and RP-91S attachments. As a result of research, the effectiveness of Denite® in the chemical binding of mercury in the soil has been proven and its optimal dosages have been determined. As a result of the positive tests of the technology of chemical immobilization of mercury, the prospect of a practical solution to the issue of demercurization of mercury-contaminated soil on the territory of the Northern industrial zone appeared.