Experimental substantiation of the hygienic assessment method of the geotubing of deposits from urban sewage treatment facilities

Every day in the city of St. Petersburg there is formed more than 10,000 m³ of sewage sludge. The main mass of deposits is stored at the landfill for storing waste with an area of up to 150 hectares. Toxic substances and pathogens contained in sediments can penetrate into the environment stipulating the significant pollution of the environment. In the arsenal of technologists dealing with the problem of sewage sludge disposal, there are numerous approaches and solutions, for instance: drying sludge, incineration, composting, vermicomposting, eco-concrete fixation. However, tried everything methodological approaches have not found their applications because of the impossibility of decrease in toxicity due to the presence of substances in the resulting substance of 1^st and 2^nd classes of danger, having a translocation mechanism of transition in plants. And, nevertheless, the problem of sewage sludge cannot be solved by used approaches because of the high toxicity caused by the presence of substances of the 1^st and 2^nd hazard classes in the obtained substance, for which the translocation mechanism of environmental contamination is characteristic. The aim of our work is the substantiation of the hygienic safety of the utilization of products obtained by geotube technology from deposits at the Northern Station for aeration «Vodokanal-SPb» in road construction. As the object of research there was selected the complex of sludge lagoons of the Northern Station for aeration «Vodokanal-SPb» located in the village of Novosilky. Sanitary-chemical, toxicological, parasitological, bacteriological, radiological. It is possible to observe the binding of ionic forms of ecotoxicants, transition of them to a bound state, which provides for the environmental safety. Helminthological and bacteriological studies show the epidemic safety of the product obtained by geotubing. Geotube technology seems to be the most promising in the treatment of accumulated sludge beds on sewage sludge.