The technical solution for the construction of local treatment of return drainage flow from an irrigated area, based on the use of ion-exchange filter materials, is proposed. It has been established that the concentration of chemicals in the water of the drainage well is 1/3 lower than in the open collector, where the drainage flow is diverted. Therefore, the localization of the technological unit for the treatment of drainage water relative to the drainage well is a reasonable decision, since it will reduce the financial costs of filter media and the frequency of their replacement. The technological scheme of the treatment plant based on the block principle is described: by disconnecting or connecting individual blocks, it is possible to respond flexibly to changing needs in the quality and degree of drainage water treatment.

Keywords: technical solution, water treatment, ion exchange, drainage flow, block approach, drainage well, water quality, chemical analysis, land reclamation, irrigation system

The advantages and disadvantages of reagent methods for cleaning groundwater from hydrogen sulphide are considered. The time of contact of hydrogen peroxide with hydrogen sulphide contained in the treated water was determined experimentally before the appearance of opalescence caused by the formation of colloidal sulfur. The equation for the time dependence for the start of the hydrogen sulfide oxidation reaction with the concentration of H2O2 is obtained, which makes it possible to calculate the required contact time of the treated water with hydrogen peroxide at a different content of hydrogen sulfide in the initial water.

Keywords: groundwater; water supply; cleaning, hydrogen sulfide, rural settlements, chlorine-containing reagents, hydrogen peroxide

The problems of drinking water supply of Russian population in rural areas, where the level of life support is lower than in urban areas are not just escalated but become depopulation factor in some regions. While developing and recommending any water treatment technology first of all it is necessary to be guided by the chemical composition of source water. In many rural areas groundwater has become the only source of drinking water, because the level of surface water contamination and hydrometric characteristics make them unsuitable for use. The data for the survey of physical and chemical composition of groundwater and groundwater from wells and public wells used in the drinking water supply of Kuibyshev district in Rostov region are delivered. The analysis showed that Kuibyshev region belongs to the areas of virtual absence in fresh groundwater resources, where groundwater with increased salinity and high content of sulfates and hardness are prevailed .The ecological assessment of using this water desalination method as reverse osmosis was carried out in this study. In areas with no centralized sewerage and sewage treatment facilities, the Kuibyshev region belongs to, using of this method is inappropriate.

Keywords: rural settlement, underground water, drinking water, salinity, hardness, purification, reverse osmosis, soil salinization.