ALROSA pays great attention to the aspects of a comfortable human environment in diamond mining, the Company tries not only to eliminate dust origin, but also to improve the aesthetic component in the areas of its operations. One of such works is land reclamation.
Starting from 2006, ALROSA annually allocates impressive sums for the recultivation of soil that was used in production and for the restoration of the habitat that was characteristic of the area before the start of diamond mining. Thus, over the past 13 years, the Company has allocated more than 950 million rubles for the restoration of the fertile layer and the planting of a dozen species of grass, shrubs and trees in the territories of all its mining and processing facilities in Yakutia, as well as the locations of exploration expeditions and capital construction, the area of which is more than 4 140 700 m2.
Extraction of minerals, including the open method, violation of soil fertility - all this has a detrimental effect on the environment. But having been at several sites last year, I could not help but notice that the piles of excavated soil and sand essentially overgrow themselves. Of course, if this is not a bare rock, the pace of this process must be artificially accelerated.
Each mining company is supervised by state supervision bodies - the Ministry of Natural Resources, the Environmental Prosecutor's Office and others. Accordingly, each organization has its own schedule for the delivery and acceptance of disturbed lands. After completion of work on a certain plot, it is supposed to restore it and then return it back to the owner (municipality or forestry establishment). This is a whole policy, which is the ability to conduct economic activities, the desire and ability to direct resources to the implementation of socially oriented activities. Nadezhda Liss, ALROSA Chief Specialist in Land Reclamation and Resource Use, told us about how to restore land after mining in the territory of Mirny district.
From overgrowing to remediation
Until 2002, the main concept of disturbed land reclamation was only to conduct the technical stage for subsequent self-overgrowing. In most cases, measures were developed on the basis of the features of the decommissioned facility and were limited solely to leveling the surface. Years went by, but there was no miraculous self-overgrowing, so the town of Mirny was surrounded by gray-blue dumps and tailings. It was necessary to change something ...
In 2002, for the first time, reclamation was viewed as the restoration of the fertile potential of land, and an integrated approach was proposed with a phased implementation of work combining both technical and biological reclamation. At the same time, the possibility of secondary development of the object, as a technogenic deposit, was retained. The analysis of domestic and foreign experience and methods of work on the reclamation of disturbed territories was carried out. Employees of the Company studied proceedings of the conference on reclamation in the city of Teplice (Czech Republic, 2001).
The first test site was the decommissioned tailing dump of the concentrator # 3 of the Mirny Mining and Processing Division. But it turned out that the proposed methods were too expensive and required improvement. So, in 2004, the scientists of Yakutia came to the rescue.
At the biological stage of remediation employees of the Institute developed a complex of agrotechnical and phytomeliorative measures aimed at improving the agrophysical, agrochemical, biochemical and other properties of the soil substrate. Such a complex of works includes the restoration of soil, vegetation, and often the landscape as a whole. It was decided not to touch the areas where there is a natural restoration of vegetation and where the composition of the soil does not interfere with the growth of plants. For this, a natural source of seeds was created, i.e. proximity of the surrounding vegetation, which was moving towards the free territories. This is how the distribution of vegetation in nature is arranged, when, it would seem, even on barren surfaces, such as rock and stones, life appears slowly but surely. The pioneers of vegetation in such places are lichens, followed by other vegetation after a while. But the measures developed were to speed up this process many times: the technogenic landscape was backfilled with a layer of potentially fertile ground in order to improve the mechanical and chemical composition of the soil, which contributed to the growth and development of vegetation. Sand is a potentially fertile layer, and sand backfilling can serve as a screen and soil for creating a sustainable grass cover. Technical solutions for remediation included measures to protect the surface of the tailings storage facility from water and wind erosion.
In 2004, employees began to study the fruits of their labors. Plants survived, but not all. “Islands of life” gave a chance to restore the entire cover. After three years, this place was unrecognizable: dense vegetation grew around it. But this was not a reason to stop there. At the same time, heaps of the Mir mine were subjected to biological recultivation.
In 2007, ALROSA purchased flowering plant seeds in Yakutsk. Plants have not just taken root, but firmly rooted and began to multiply. On the site also grew tree species, and many other herbaceous plants. Today, on the site of the former tailing dump there is a whole variety of grass, school students can even go here for field research and botanize. But this is not all: the Company's employees planted black currant bushes and even strawberries there, which have not only taken root, but fruit well now.
Following on from the success, all waste objects with disturbed lands in the area of the city of Mirny were subjected to biological recultivation. The total area of reclamation was 414 hectares. Seeds of clover, rump, fescue, rapeseed, scarified (without seed cover to accelerate growth), seeds of alfalfa, sweet clover and deervetch were purchased and sown.
Reclamation of Aikhal and Udachny Mining Divisions facilities
In the period from 2011 to 2012, the experiment began in Aikhal. After 5 years, in 2017, ALROSA began the selection of seed for the biological recultivation of industrial facilities at the Udachny and Aikhal mining and processing plants. The work was based on the experience of Mirny, but in this case it was necessary to carry out work in more severe climatic and soil conditions.
The Company's employees used river silt of overburden of the Piropovy Creek alluvial deposit as a fertile layer. Seeding was carried out in 2017-2018 with the involvement of specialists from the Botanical Garden of the Institute for Biological Problems of Cryolithozone. During this time, 10 hectares of disturbed land were reclaimed. In the first year, shoots of saltwort appeared - succulents growing on saline soils. In the second year of work, it became obvious that the plants had taken root and formed a dense vegetation cover, and over time the vegetation begins to change, more demanding plants grow. So, the methods developed in Mirny work in Udachny when applying a fertile layer.
One can do the work of ten
Today Nadezhda Yurievna does not stop at what has been accomplished, and as a true enthusiast she continues research on the selection of a method of biological remediation without the presence of a fertile layer. And all this in order to return primevalness to the territories where mining operations were carried out.
In the process of communication, it turned out that Nadezhda Liss works without a team under the leadership of the Company. If necessary, at different stages of work, she can attract almost any employee of the Company. If a surveyor is needed, then this employee enters into the designated scope of work, and if botanists are needed, then they are connected to the workflow. But it all starts at the technical stage, when a working draft is formed. It reflects the conditions and features of the relief, soil, terrain, and climate. Here, in fact, a whole team of specialists, designing engineers works. The quality of the preparatory and technical work has a direct impact on the result - survival of plants. Therefore, they pay special attention to the first stage.
The biological stage of reclamation involves the seeding of perennial grasses, planting trees and shrubs. Everything must be weighed and strictly regulated, a selection of plants must be carried out to bring in new life on the once lifeless earth. And the once disturbed land will bloom and sparkle in different colors, like a diamond, after cutting a rough stone.
by Andrey SHILOV