SLUDGE DEPOSITS OF A FORMER PHOSPHOR-PRODUCING PLANT AS AN OBJECT OF ACCUMULATED ENVIRONMENTAL DAMAGE AND A SOURCE OF PUBLIC HEALTH RISKS

Abstract

Introduction. The study is relevant due to many objects of accumulated environmental damage located in Russia and the necessity to identify priority ones for immediate elimination to reduce health and environmental hazards. The aim of the study was to assess and characterize public health risks on a territory influenced by sludge deposits created by formed economic activities of a phosphor-producing plant.
 Materials and methods. Sludge deposits with the total volume of wastes higher than 287 thousand m3 were selected as a research object. They were located in close proximity to a residential area and had been abandoned for 14 years. Their total square equaled 8.4 hectares. We collected background data and technical documentation on the object of accumulated environmental damage and accomplished wide-scale instrumental measurements of soils, surface water, and ambient air on the territory influenced by it. Health risks were assessed using the method based on fuzzy set theory; more than 50 quantitative and qualitative indicators were considered in the process. They described the object itself as well as ambient air, water, soil, and public health on adjoining territories.
 Results. The study gave evidence that the phosphor sludge deposits polluted environmental objects with heavy metals (manganese, arsenic, cadmium, cobalt, nickel, mercury, and lead). Nickel levels in water equaled 7.5 MPC and mercury levels reached 10 MPC. Apart from metals, soils were polluted with impermissible levels of oil products and microbes. Health risks were estimated as ‘high’ for people living in the closest settlement. Major causes for such high risks include toxicity of wastes, a long period during which the object has existed as a source of pollution, and its proximity to residential areas.
 Conclusion. The object creates high health risks and is to be eliminated immediately.