Assessment of the Radiation - Ecological state and Migration of radionuclides of the Adrasman UraniumWastes Tailings dump of Northern Tajikistan
Project Status: 2 Submitted to Parties for Board Decision
Duration in months: 36 months
Objective
The project objective is the organization and implementation of systematic radiation monitoring program of the territories (tailings dump) in the district village of Adrasman (Northern Tajikistan) and nearby contaminated areas with an increased radiation background. It is planned to study the migration of radionuclides to atmospheric air, soil and water objects of the studying areas, assessment of the geotechnical and geophysical state of the tailings dump, the ecological situation in the region, and develop practical recommendations on this basis to the region population to reduce external and internal exposures, correction of the radiation safety norms for different population groups, preparation of recommendations for carrying out remediation works at the Adrasman tailing dump.
In order to increase public awareness in the field of radiation safety, methodological recommendations will be developed and training seminars will be held.
The research status in the field. It is clarified that for about 46 years since 1945 to 1991, about 80000 tons of uranium protoxide (yellow cake) were extracted at the hydrometallurgical plants of Tajikistan after the processing of uranium ore, which were located in the cities of Istiklol (formerly Taboshar), Buston (formerly Chkalovsk) and Adrasman settlement , which the USSR used for military and energy needs. As a result, Tajikistan inherited from the Soviet Union - a huge amount of waste of uranium raw materials, abandoned uranium sites, mines and quarries.
Despite the differences of volumes of burial, their areas and the level of activity, all radiation contaminated sites according to the location have common threats and risks – all of them are located in the population residential areas (Chkalovsk, Taboshar, Khujand, Adrasman) or in the watershed of rivers with transnational significance, such as the Syr Darya, which flows through the Fergana Valley, crossing the territory of Kyrgyzstan, Tajikistan, Uzbekistan and Kazakhstan, as well as in the upper reaches of the water tributaries and sais flowing into the Syr Darya; all facilities are located in seismically hazardous areas; due to climatic conditions, all objects are subject to wind and water erosion.
Studies on Tajik legacy sites have shown that the current situation with waste management and the environmental situation as a whole is inadequate.
Three districts, where located the tailings and dumps, are in the unsatisfactory state, namely: in the region of the town of Taboshar, the villages of Adrasman, as well as the existing Digmai tailing pond located in the vicinity of the town of Chkalovsk. Surfaces of tailing dumps, especially those that do not have protective coatings or are susceptible to the destructive effects of natural factors or burrowing animals, pose a threat due to a significant dispersion of contaminants and tail material beyond their primary location.
In addition, almost all sites are freely available to the local population and livestock, and as mentioned, all areas are located in the seismically active zone
Thus, currently, the Taboshar, Digmai and Adrasman tailing dumps are in critical condition.
At the tailing dumps of the Taboshar region and Digmai by the support of the IAEA TC projects, ISTC projects (T-2076, T-1508), UNDP and other international organizations, a number of research and monitoring works on the radiation impact risk assessment of these tailings on the environment and health of the population are carried out. As a result, at the present time, with the financial support of the European Commission and the Intergovernmental Targeted Program of the CIS countries, rehabilitation work has begun on the tailing dumps of Taboshar and Digmai. We hope that these programs will be successfully implemented and the sites will be rehabilitated.
However, the state of the third tailings dump - Adrasman is of particular concern.
Below is a brief historical summary of the tailings dump Adrasman.
Hydrometallurgical plant for uranium processing in the village of Adrasman operated from 1941 to 1957. The plant was built at the highest point of the village in such a way that the tails descended along wooden trenches. Mountain sais below the plant, previously blocked by a pioneer dam, were used as tailings. Thus, in the village of Adrasman, six tailing dumps were formed, each of which contained 60 to 100 thousand tons of waste from uranium ore processing. Because of the lack of raw materials in 1955, the plant was redesigned for the processing of lead-zinc ore to produce lead concentrate [11].
During 1991-1992 years, out of six pre-existing tailing dumps, one was created, where the remaining wastes were redeployed. However, due to various reasons, the burning project was not performed fully. The thickness of the neutral coarse clastic layer is not more than 0.5 m, there is no mudflow dam. As a result of flood events and mud rains, a partial erosion of the surface protective layer occurs annually, in spring and autumn, the tails become exposed and washed down through residential houses and garden plots in Karamazar-Sai. In 2004-2005 after the mud rains, an inert soil erosion occurred and the formation of erosion in width from 2 to 9 m, depth up to 2.5 m and length along the slope up to 30 m. Radioactive waste has spread down along the sai, reaching private sections of the village dwellers located at a distance of up to 300 m from the tailing dump. Although the erosion has now been eradicated, a temporary dam has been built along and across the tailing dump, but these measures are temporary and can not completely solve the issue of radiation safety of this site.
Considering the risks related to the human factor, the ecological illiteracy of the population, then the danger of radiation exposure to the local population is high, because of people opened the mines and collected contaminated metal, pipes, sleepers, wires, etc. for personal use and sale, not only in the territory of the region, but also to neighboring countries without knowing about their radioactivity, grazed livestock in the territory of these facilities, allocated plots for the construction of houses and the layout of personal gardens and vegetable gardens near these facilities without taking into account the sanitary protective zone.
Numerous studies conducted on the territory of the Adrasman tailing dump have the nature of collecting statistics, without pursuing the primary goal of radiation monitoring - developing practical recommendations for the consumer to improve the state of the radiation situation, based on an integrated approach to analysing and developing new effective low-cost methods for total monitoring, and for improving soil quality and water in order to reduce the radiation risk.
Projects implemented by the support of international organizations in the Republic of Tajikistan (IAEA, TACIS, NATO, ISTC, UNDP) were focused at determining the condition of tailing dumps of uranium industry waste, applying international standards for safe management of mining and uranium production residues, and developing measures to solve the open tailing pits rehabilitation problems of "Factories of poor ores" in the city of Istiklol (formerly Taboshar), "Digmai", and protective measures at the former uranium objects of the North Tajikistan.
