On September 18, 1986, a commission of the USSR Ministry of Defense arrived in Chernobyl. The purpose of the visit was to resolve the issue of attracting military personnel to work on cleaning the roof of the third Chernobyl nuclear power unit from radioactive materials.
The commission was initially categorically against involving military personnel in this dangerous work. However, the decision of the Government Commission entrusted this work to the military due to the impossibility of using remotely controlled mechanisms and the civilian population.
Basically, parts of the engineering forces took part in solving the tasks of cleaning the roof of the 3-rd power unit from radioactive sources. The dose limit of 20 rem was determined by the radioactive load limit, which made it possible for each military man to be in the danger zone for up to 3 minutes.
Dosimetrists scouts were the first to go up there, before sending people to collect the debris of nuclear fuel. They have developed 660 routes. In total, 1,021 military personnel worked on the roof in the course of the decontamination of the third power unit in September 1986, and in December, another 1,500 people decontaminated it.
In accordance with the decision of the Government Commission, work on cleaning the roof of the third power unit had been completed by the end of September by volunteer servicemen. The average dose of their exposure was 10 rem.
At the same time, the military bitterly noted that the weak point of decontamination of the station was the lack of small-scale mechanization. All extremely important events were carried out with a broom, a bucket with a rag and a shovel – with the help of such uncomplicated tools, and even with a high level of radioactive contamination.
Difficult and multidimensional tasks faced the military, who took part in the implementation of the process of putting into operation the 3-rd power unit of the station. The complexity and danger consisted in the fact that the ventilation for the 3rd and 4th power units continued to work immediately at the time of the accident and a few hours after it, which moved radioactive aerosols to the 3-rd unit, and some of them settled directly on internal surfaces of air ducts.
In addition, gaps in the roof and walls were formed as a result of the explosions, doors and windows were knocked out, which contributed to the formation of uncontrolled leaks of radioactively contaminated water and drafts, which caused secondary pollution of the premises.
The most important work took place on the destroyed 4-th power unit
In addition to plugging and decontamination, the military performed another very large and important work — the burial of the destroyed 4-th block. By the forces of the engineering troops, it began with the construction of a protective wall around the collapse 6 meters thick and at the same time decontamination of the territory around the power unit. 26 engineering battalions for various purposes, the current number of which was more than 8000 people and about 900 units of special engineering equipment, performed the work under the radiation background from 5 to 370 X-rays per year.
The need for continuous monitoring of aerosol emissions in the crater of the destroyed reactor of the 4th block and monitoring of areas with high radiation levels pushed the workers of the Military Academy of Chemical Protection and the Institute of Atomic Energy named after Kurchatov to the organization of mobile remote control installations.
There was a search for the most rational ways to control environmental pollution, in particular air, along with the control of internal and external pollution of the premises of the 4th block. The need for continuous monitoring of emissions led to the development of a special method for sampling aerosols in the air shelf above the furnace core.
The fulfillment of this task became possible only thanks to a clear distribution of responsibilities among all participants in this process. The Ministry of Defense, the State Committee for Hydrometeorology, the Ministry of Chemical Industry, the Academy of Sciences of the USSR and other departments were involved in this work.
Original technical solutions were often used in solving problems that arose during the construction of a shelter over the destroyed 4th power unit. Remote-controlled equipment was needed to perform work at the Shelter object.Therefore, a production association of robotics and emergency recovery work was quickly created in the system of the USSR Ministry of Atomic Energy, which included a design and engineering bureau, pilot production and emergency technical center.
The production association of robotics and emergency recovery was entrusted with the functions of the customer to create a robotic complex of remotely controlled systems for work in conditions of high radiation.
An integrated radiation cleaning system included:
- development of high-tech fire extinguishing means at nuclear power plants;
- personnel training for working in conditions of increased radiation during accidents, equipment repair, decommissioning and conservation of nuclear power units;
- tests of the created samples of robotic systems and remotely controlled systems for nuclear energy, including conducting field tests;
- organization of work using robotic systems and remotely controlled systems in conditions of increased radiation, with decommissioning and conservation of power units;
- organization of work on equipment repair in emergency situations, as well as in accidents at nuclear plants with a dangerous release of radioactive substances into the atmosphere and liquidation of the consequences of these accidents;
- continuation of work in the resettlement zone of the Chernobyl nuclear power plant for servicing radioactive waste disposal facilities, decontamination and dust suppression, restoration of buildings and structures.
Ensuring the long-term and controlled burial of fuel of the fourth power unit was a responsible and extremely difficult task. Its successful solution was possible only with a correctly selected work strategy.
Therefore, in front of the Institute of Atomic Energy named after Kurchatov, and the Construction Directorate was tasked by December 1987 to prepare groundwork on the need to carry out special activities to ensure this requirement. There is no reason to doubt that these developments were prepared much earlier than the deadline. Nobody gave time for long thoughts, and time itself did not play on the side of developers.