The Institute undertook a comprehensive scientific study. Based on the results of the study, the municipality undertook to develop, adopt and implement a program to combat high levels of dust in the city. InDriver company took over the financing of the research as one of the Sinet Team projects aimed at the development of Yakutia.
During the study, throughout the year, scientists from the Institute of Permafrost Studies in Yakutsk carried out work to identify the volume and chemical composition of dust and the causes of dustiness of the city. The specialists of the Institute carried out the work in three stages: they installed 10 stationary dust collectors, took samples of soil and snow cover throughout the city. The contents of the dust collectors and snow samples were divided into liquid and solid parts through special filters for laboratory studies of the concentration of heavy metals.
Installing the dust collectors
The main conclusion of the study: the main reason for increased dustiness in Yakutsk is the type of soil in the city and its surroundings, as well as the influence of global and local anthropogenic factors on its degradation. Sandy-clay soils, which are common in Yakutsk, are prone to turning into dust if they dry out and are exposed.
Drying occurs mainly due to the lowering of the groundwater level. The reason for the decrease is complex. Global warming and anthropogenic factors — construction, generation and accumulation of heat by buildings and infrastructure facilities - lead to an increase in the volume and acceleration of the rate of permafrost melting. Also, human activity disrupts the natural flow of aboveground and underground waters, which leads in some places to waterlogging, in others to drying. Also, the more soil is exposed, losing the top layer, the more it dries out.
There are two main causes of soil exposure: the death of vegetation due to drying and soil pollution, the felling of trees and the expansion of urban infrastructure - primarily the construction of buildings, the laying of roads and communications.
In addition, a significant contribution is made by suspended particles contained in exhaust gases, smoke from stationary sources (CHP, production), and the import of sand and soil into the city from the outside for various purposes — construction, road sprinkling, etc., but their contribution is significantly less compared to the natural causes described above, and identifying the exact proportion requires additional research, for example, a comparative analysis of the composition of soil and sand from different sources.
The dust in the city is unevenly distributed. For example, at the intersections of the Okruzhnoye Highway-Zhornitsky, Lermontov-Kalandarishvili and at the Tuimaada stadium, the level of dust pollution is hundreds of times higher than the natural background value.
According to the average value of the dust load level, the most unfavorable are the administrative districts of Avtodorozhny and Oktyabrsky, and relatively "clean" — Gagarinsky and Saysarsky districts. The highest concentration was found in the area of the intersection of the Ring highway — Zhornitsky, the lowest - in the Rechnoy port.
The contribution to dusting is made not only by heavy traffic, but also by the condition of the green zone, which is assessed as unsatisfactory due to the small number of lawns, shrubs and trees. There are very few parks and squares in the city compared to other cities.
The problem of dustiness is aggravated by the large-scale delivery of sand for sprinkling roads. According to 2019 data, 4 thousand cubic meters of sand were delivered to Yakutsk, calculated at 18 kilograms for each citizen.
In the course of the study, it was expected to be confirmed that winter dust concentrations (with snow cover) are much lower - about 5% in relation to summer.
If we talk about the toxicity of dust in Yakutsk, it contains many harmful elements, but within the permissible limits and with point exceedances. High concentrations of phosphorus are mainly associated with unauthorized landfills. The most contrasting anomalies of lead are observed in the area of the old landfill (Vilyuysky Lane) - a city snow storage area and to the northeast of the GRES (hydroelectric power station) area, where lead concentrations rise to 100-120 mg/kg (3-4 times higher than the MPC). According to scientists, from 2003 to 2008, the concentration of lead in the soils of main streets began to decrease significantly, this is due to the intensive improvement of the city. A further decrease in the concentration of lead is probably due to an improvement in the quality of automotive fuel.
Dynamics of changes in the concentration of heavy metals in the soils of Yakutsk
(Makarov, 2013) and new data
Note: Q, background - background content of heavy metals in quaternary deposits of the Tuimaada valley. The concentration of metals exceeding the maximum permissible norm is highlighted in bold. Dash - no data available
The most contrasting anomalies in the soils of the city were found in the areas of GRES (hydroelectric power station) and Yakutsk Thermal Power Plant. A comprehensive environmental assessment of the city by the level of soil and snow cover pollution showed that the greatest pollution of the atmosphere and soil cover is observed in the northern part of Yakutsk (airport, nuclear power plant, building materials plant) and in the southern part - in the DSK (house - building plant) area. These areas of the city include the most polluted lake systems.
In general, air pollution in Yakutsk constantly exceeds sanitary standards: in summer - 2.1 times, in winter - 1.6 times. The most dangerous are medium and fine particles, which occupy about 10% of the volume and are able to penetrate into the deep parts of the lungs, up to the alveoli, which creates risks to human health. In recent years, toxic smoke from forest fires has been added to the dust problem.
Nikolay Torgovkin, author of the study, Candidate of Geological and Mineralogical Sciences:
— There are things that are outside our zone of influence. For example, since the 60s of the 20th century, there has been a noticeable increase in the average air temperature, and the arid climate of Central Yakutia does not have the best effect on soil salinity and degradation of the vegetation layer. There are also technogenic factors, which include an increase in the number of vehicles (according to 2019, every third citizen has a car), and an insufficient level of landscaping (only 60% of the roads of Yakutsk are paved). Emissions from stationary sources and transport amount to 45,400 tons per year. Sandy-dusty material is used for the construction of buildings, roads and the fight against ice. All this together leads to high dustiness. In addition, in Yakutsk, the natural flow of surface and permafrost waters is disrupted, since the road network and backfills act as dams. As a result, we have an uneven distribution of moisture and the appearance of swampy and desiccated areas. How do we see the fight against dust? To put it briefly, it looks like this.
Minimize the area of open soil along roads and in courtyards.
At the municipal and republican levels, introduce requirements for developers and road builders in terms of sheltering construction zones, as well as the obligation to restore the topsoil after completion of work.
Mass planting of trees and shrubs along the streets.
Up to 72% of suspended dust particles and up to 60% of sulfur dioxide settle on the leaves. Tree planting should be carried out with the involvement of specialists. It is also necessary to monitor green spaces with the help of high-resolution satellite images and unmanned aerial vehicles - drones.
To introduce cleaning filters for thermal power facilities.
Although the current enterprises are modernizing in the direction of improving environmental-saving properties, the atmosphere of the city is heavily polluted.
Prohibition of deforestation and shrubs.
In addition to the gradual disappearance of forests, the ecological situation is affected by unauthorized landfills, aerial photography showed that there are more than 200 points on the territory of Yakutsk.
Replacement of the anti-icing coating.
Instead of river fine-medium-grained sand, it is necessary to use a larger fraction (coarse-grained Kildyam sand or gravel), since it is less susceptible to cryogenic weathering.
To ensure an effective runoff of surface and permafrost waters.
This is a very difficult task, which will probably be solved by the introduction of a system of intra-quarterly accumulative runoff, proposed by my colleague, Professor Viktor Vasilyevich Shepelev.
Implement annual system of monitoring of soils and dust.
Monitoring should be carried out in summer and winter with the use of modern high-precision chemical analytical laboratory methods.
Arsen Tomsky, founder of Sinet Team:
— I am very grateful to the scientists of the P.I. Melnikov Permafrost Institute of the SB RAS for the large amount of work carried out. We are submitting a full report to Government house-1 and the Mayor's Office. If the authorities confirm their readiness to move forward on the dust problem, then we will look for experienced urban experts in Russia and, possibly, beyond its borders, so that they carefully study the data obtained, look at the situation in the city themselves and help develop an anti-dust program for republican or municipal authorities. I hope that it will be adopted and implemented. Sinet will be ready to take part in it as much as possible.
The full report on the results of the study of the causes of dust in Yakutsk can be found at the link.