What is radioactive waste. Nuclear burial ground: how radioactive waste is stored. Reuse of radioactive waste

Radioactive waste (RW) is a by-product of technical activity containing biologically hazardous radionuclides. RAW is formed:

• at all stages of nuclear energy (from fuel production to the operation of nuclear power plants (NPPs), including nuclear power plants (NPPs);
• in the production, use and destruction of nuclear weapons in the production and use of radioactive isotopes.

RW is classified according to various criteria (Fig. 1): according to the state of aggregation, according to the composition (type) of radiation, according to the lifetime (half-life T 1/2), by activity (radiation intensity).

Among RW, liquid and solid are considered to be the most common in terms of aggregate state, mainly arising during the operation of nuclear power plants, other nuclear power plants and at radiochemical plants for the production and processing of nuclear fuel. Gaseous radioactive waste is generated mainly during the operation of nuclear power plants, radiochemical plants for fuel regeneration, as well as during fires and other emergencies at nuclear facilities.

Radionuclides contained in radioactive waste undergo spontaneous (spontaneous) decay, during which one (or several in succession) of the types of radiation occurs: a -radiation (flux a -particles - doubly ionized helium atoms), b -radiation (flow of electrons), g -radiation (hard short-wave electromagnetic radiation), neutron radiation.

The processes of radioactive decay are characterized by an exponential law of decrease in time of the number of radioactive nuclei, while the lifetime of radioactive nuclei is characterized by half-lifeT 1/2 - the period of time during which the number of radionuclides will decrease by half on average. The half-lives of some radioisotopes formed during the decay of the main nuclear fuel - uranium-235 - and representing the greatest danger to biological objects, are given in the table.

Table

Half-lives of some radioisotopes

The United States, which actively conducted tests at one time atomic weapons in the Pacific Ocean, used one of the islands for disposal of radioactive waste. The containers with plutonium stored on the island were covered with powerful reinforced concrete shells with warning inscriptions visible for several miles: stay away from these places for 25 thousand years! (Recall that the age of human civilization is 15 thousand years.) Some containers were destroyed under the influence of incessant radioactive decays, the level of radiation in coastal waters and bottom rocks exceeds the permissible limits and is dangerous for all living things.

Radioactive radiation causes the ionization of atoms and molecules of matter, including the matter of living organisms. The mechanism of the biological action of radioactive radiation is complex and not fully understood. Ionization and excitation of atoms and molecules in living tissues, occurring when they absorb radiation, is only the initial stage in a complex chain of subsequent biochemical transformations. It has been established that ionization leads to the breaking of molecular bonds, changes in the structure of chemical compounds and, ultimately, to the destruction of nucleic acids and proteins. Under the action of radiation, cells are affected, primarily their nuclei, the ability of cells to normal division and metabolism in cells are disrupted.

Hematopoietic organs (bone marrow, spleen, lymphatic glands), epithelium of mucous membranes (in particular, intestines), and thyroid gland are most sensitive to radiation exposure. As a result of the action of radioactive radiation on organs, severe diseases occur: radiation sickness, malignant tumors (often fatal). Irradiation has a strong effect on the genetic apparatus, leading to the appearance of offspring with ugly deviations or congenital diseases.

Rice. 2

A specific feature of radioactive radiation is that they are not perceived by the human senses and even at lethal doses do not cause pain in him at the time of exposure.

The degree of biological effects of radiation depends on the type of radiation, its intensity and duration of exposure to the body.

The unit of radioactivity in the SI system of units is becquerel(Bq): 1 Bq corresponds to one act of radioactive decay per second (non-systemic unit - curie (Ci): 1 Ci = 3.7 10 10 decay acts per 1 s).

absorbed dose (or radiation dose) is the energy of any type of radiation absorbed by 1 kg of matter. The unit of dose in the SI system is gray(Gy): at a dose of 1 Gy in 1 kg of a substance, when absorbing radiation, energy of 1 J is released (non-systemic unit - glad: 1 Gy = 100 rad, 1 rad = 1/100 Gy).

The radioactive sensitivity of living organisms and their organs is different: the lethal dose for bacteria is 10 4 Gy, for insects - 10 3 Gy, for humans - 10 Gy. The maximum dose of radiation that does not cause harm to the human body with repeated exposure is 0.003 Gy per week, with a single exposure - 0.025 Gy.

The equivalent dose of radiation is the main dosimetric unit in the field of radiation safety, introduced to assess the possible damage to human health from chronic exposure. The SI unit of equivalent dose is sievert(Sv): 1 Sv is the dose of radiation of any kind that produces the same effect as the reference X-ray radiation in 1 Gy, or in 1 J/kg, 1 Sv = 1 Gy = 1 J/kg (non-systemic unit - rem(biological equivalent of a roentgen), 1 Sv = 100 rem, 1 rem = 1/100 Sv).

The energy of an ionizing radiation source (IRS) is usually measured in electron volts (eV): 1 eV = 1.6 10 -19 J, it is permissible for a person to receive no more than 250 eV from IRS per year (single dose - 50 eV).

Unit x-ray(P) is used to characterize the state of the environment subjected to radioactive contamination: 1 P corresponds to the formation of 2.082 million pairs of ions of both signs in 1 cm 3 of air under normal conditions, or 1 P \u003d 2.58 10 -4 C / kg (C - pendant) .

Natural radioactive background - the permissible equivalent dose rate from natural radiation sources (the Earth's surface, atmosphere, water, etc.) in Russia is 10-20 μR / h (10-20 μrem / h, or 0.1-0.2 µSv/h).

Radioactive contamination has a global character not only in terms of the spatial scale of its influence, but also in terms of the duration of its action, threatening people's lives for many decades (the consequences of the Kyshtym and Chernobyl accident) and even centuries. Thus, the main "stuffing" of atomic and hydrogen bombs - plutonium-239 (Pu-239) - has a half-life of 24 thousand years. Even micrograms of this isotope, once in the human body, cause cancer in various organs; three "oranges" of plutonium-239 could potentially destroy all of humanity without any nuclear explosions.

In view of the absolute danger of radioactive waste for all living organisms and for the biosphere as a whole, they need to be decontaminated and (or) thoroughly buried, which is still an unresolved problem. The problem of combating radioactive contamination of the environment is brought to the fore among other environmental problems due to its huge scale and especially dangerous consequences. According to the famous ecologist A.V. Yablokov, "environmental problem number 1 in Russia - its radioactive contamination."

The unfavorable radiological situation in certain regions of the world and Russia is primarily the result of a long-term arms race during the Cold War and the creation of weapons of mass destruction.

For the production of weapons-grade plutonium (Pu-239) in the 1940s. the first nuclear power plants were built - reactors (tens of tons of Pu-239 are required for nuclear weapons; one ton of this "explosive" is produced by a slow-neutron nuclear reactor with a capacity of 1000 MW - one unit of a conventional nuclear power plant of the Chernobyl type has such power). Tests nuclear powers(USA, USSR, and then Russia, France and other countries) of nuclear weapons in the atmosphere and under water, underground nuclear explosions for "peaceful" purposes, which are now subject to a moratorium, have led to severe pollution of all components of the biosphere.

Under the program "Peaceful atom" (the term was proposed by the American President D. Eisenhower) in the 1950s. NPP construction began first in the USA and the USSR, and then in other countries. At present, the share of nuclear power plants in the production of electrical energy in the world is 17% (in the structure of the Russian electric power industry, the share of nuclear power plants is 12%). There are nine nuclear power plants in Russia, of which eight are located in the European part of the country (all stations were built during the existence of the USSR), including the largest - Kursk - with a capacity of 4000 MW.

In addition to the arsenal of nuclear weapons (bombs, mines, warheads), nuclear power plants that produce explosives, and nuclear power plants, the sources of radioactive contamination of the environment in Russia (and adjacent territories) are:

• nuclear icebreaker fleet, the most powerful in the world;
• submarine and surface warships with power nuclear power plants (and carrying nuclear weapons);
• ship repair and shipyards of such ships;
• enterprises involved in the processing and disposal of radioactive waste of the military-industrial complex (including decommissioned submarines) and nuclear power plants;
• sunken nuclear ships;
• spacecraft with nuclear power plants on board;
• RW disposal sites.

It should be added to this list that the radiation situation in Russia is still determined by the consequences of accidents that occurred in 1957 at the Mayak Production Association (PO) (Chelyabinsk-65) in Kyshtym (Southern Urals) and in 1986 at the Chernobyl NPP (ChNPP) 1 .

Until now, agricultural land in the Republic of Mordovia and 13 regions of the Russian Federation on an area of ​​3.5 million hectares is still subject to radioactive contamination as a result of the accident at the Chernobyl nuclear power plant. (The consequences of the Kyshtym accident are discussed below.)

The total area of ​​the radiation destabilized territory of Russia exceeds 1 million km 2 with more than 10 million people living on it. At present, the total activity of unburied radioactive waste in Russia is more than 4 billion Ci, which is equivalent in terms of the consequences of eighty Chernobyl disasters.

The most unfavorable radiation environmental situation has developed in the north of the European territory of Russia, in the Ural region, in the south of the West and East Siberian regions, in the places where the Pacific Fleet is based.

The Murmansk Region surpasses all other regions and countries in terms of the number of nuclear facilities per capita. There are widespread objects that use various nuclear technology. Of the civilian facilities, this is primarily the Kola NPP (KAES), which has four power units (two of them are approaching the end of their resource). About 60 enterprises and institutions use various radioisotope technological control devices. Murmansk Atomflot has seven icebreakers and one lighter carrier with 13 reactors.

The main number of nuclear facilities is associated with the armed forces. The Northern Fleet is armed with 123 nuclear-powered ships with 235 nuclear reactors; coastal batteries include a total of 3-3.5 thousand nuclear warheads.

Extraction and processing of nuclear raw materials is carried out on the Kola Peninsula by two specialized mining and processing plants. Radioactive waste generated during the production of nuclear fuel, during the operation of the KNPP and ships with nuclear power plants, accumulate directly on the territory of the KNPP and at special enterprises, including military bases. Low-level radioactive waste from civilian enterprises is buried near Murmansk; Waste from the KNPP after holding at the station is sent for processing to the Urals; part of the nuclear waste of the navy is temporarily stored on floating bases.

A decision was made to create special RW repositories for the needs of the region, in which already accumulated waste and newly generated waste will be buried, including those that will be generated during the decommissioning of the first stage of the KNPP and ship nuclear power plants.

In the Murmansk and Arkhangelsk regions, up to 1 thousand m 3 of solid and 5 thousand m 3 of liquid RW are formed annually. The indicated level of waste has been maintained for the last 30 years.

Since the late 1950s to 1992, the Soviet Union disposed of solid and liquid radioactive waste with a total activity of 2.5 million Ci in the Barents and Kara Seas, including 15 reactors from nuclear submarines (NPS), three reactors from the Lenin icebreaker (of which 13 were emergency nuclear submarine reactors, including six with unloaded nuclear fuel). Flooding of nuclear reactors and liquid radioactive waste also occurred at Far East: in the Sea of ​​Japan and the Sea of ​​Okhotsk and off the coast of Kamchatka.

Nuclear submarine accidents create a dangerous radiological situation. Of these, the most famous tragedy of the nuclear submarine "Komsomolets" (April 7, 1989), which received worldwide resonance, resulted in the death of 42 crew members, and the boat lay on the ground at a depth of 1680 m near Bear Island in the Barents Sea at 300 nautical miles off the coast of Norway. The reactor core of the boat contains approximately 42 thousand Ki strontium-90 and 55 thousand Ki cesium-137. In addition, the boat has nuclear weapons with plutonium-239.

The region of the North Atlantic, where the disaster occurred, is one of the most biologically productive in the World Ocean, has a special economic importance and is included in the sphere of interests of Russia, Norway and a number of other countries. The results of the analyzes showed that so far the release of radionuclides from the boat into the external environment is insignificant, but a contamination zone is forming in the area of ​​flooding. This process can be impulsive, especially dangerous is the contamination with plutonium-239 contained in the warheads of the boat. The transfer of radionuclides along the trophic chain seawater–plankton–fish threatens with serious environmental, political and economic consequences.

On Southern Urals in Kyshtym, the Mayak Production Association (Chelyabinsk-65) is located, where since the late 1940s. regeneration of spent nuclear fuel. Until 1951, liquid RW arising during processing simply merged into the Techa River. Through the network of rivers: Techa-Iset-Ob, radioactive substances were carried out to the Kara Sea and with sea currents to other seas of the Arctic basin. Although such discharge was subsequently stopped, after more than 40 years, the concentration of radioactive strontium-90 in some sections of the Techa River exceeded the background by 100–1000 times. Since 1952, nuclear waste has been dumped into Lake Karachay (named technical reservoir No. 3) with an area of ​​10 km2. Due to the heat generated by the waste, the lake eventually dried up. Backfilling of the lake with soil and concrete began; for the final backfill, according to calculations, ~800 thousand m of rocky soil will still be required at a cost of 28 billion rubles (in 1997 prices). However, a lens filled with radionuclides was formed under the lake, the total activity of which is 120 million Ci (almost 2.5 times higher than the radiation activity during the explosion of the 4th Chernobyl power unit).

Recently it became known that in 1957 a serious radiation accident occurred at the Mayak Production Association: as a result of the explosion of a container with radioactive waste, a cloud with a radioactivity of 2 million Ci was formed, stretching for 105 km in length and 8 km in width. Serious radiation contamination (approximately 1/3 of Chernobyl) was subjected to an area of ​​15 thousand km 2, which was inhabited by more than 200 thousand people. A reserve was created on the radiation-contaminated territory, where observations of the living world were carried out for decades under conditions of increased radiation. Unfortunately, the data of these observations were considered secret, which made it impossible to give the necessary medical and biological recommendations in the liquidation of the Chernobyl accident. Accidents at "Mayak" occurred many times, the last time - in 1994. At the same time, as a result of the partial destruction of the radioactive waste storage near Petropavlovsk-Kamchatsky, a temporary increase in radiation compared to the background by 1000 times occurred.

Up to now, up to 100 million Ci of liquid radioactive waste are generated annually at the Mayak Production Association, some of which are simply dumped into surface water bodies. Solid radioactive waste is stored in trench-type burial grounds that do not meet safety requirements, as a result of which more than 3 million hectares of land are radioactively contaminated. In the zone of influence of the Mayak Production Association, the levels of radioactive contamination of air, water and soil are 50–100 times higher than the average values ​​for the country; there was an increase in the number of oncological diseases and childhood leukemia. The enterprise has begun construction of complexes for vitrification of high-level and bituminization of medium-level radioactive waste, as well as trial operation of a metal-concrete container for long-term storage of spent nuclear fuel from RBMK-1000 series reactors (reactors of this type were installed at the Chernobyl nuclear power plant).

The total radioactivity of existing radioactive waste in the Chelyabinsk zone, according to some estimates, reaches a huge figure - 37 billion GBq. This amount is enough to turn the entire territory former USSR in an analogue of the Chernobyl resettlement zone.

Another hotbed of "radioactive tension" in the country is the mining and chemical plant (MCC) for the production of weapons-grade plutonium and processing of radioactive waste, located 50 km from Krasnoyarsk. On the surface, it is a city without a definite official name (Sotsgorod, Krasnoyarsk-26, Zheleznogorsk) with a population of 100,000; the plant itself is located deep underground. By the way, there are similar objects (one at a time) in the USA, Great Britain, France; such a facility is under construction in China. Of course, little is known about the Krasnoyarsk Mining and Chemical Combine, except that the processing of RW imported from abroad brings in $500,000 per 1 ton of waste. According to experts, the radiation situation at the mining and chemical complex is measured not in microR/h, but in mR/s! For decades, the plant has been pumping liquid radioactive waste into deep horizons (according to data for 1998, ~50 mln m The Yenisei can be traced at a distance of over 800 km.

However, burial of highly radioactive waste into underground horizons is also used in other countries: in the USA, for example, radioactive waste is buried in deep salt mines, and in Sweden - in rocks.

Radioactive pollution of the environment by nuclear power plants occurs not only as a result of emergency circumstances, but quite regularly. For example, in May 1997, during technological repairs at the Kursk NPP, a dangerous leak of cesium-137 into the atmosphere occurred.

Nuclear industry enterprises deal with the production, use, storage, transportation and disposal of radioactive substances. In other words, RW generation accompanies all stages of the nuclear power fuel cycle (Fig. 2), which imposes special requirements on ensuring radiation safety.

Uranium ore is mined in mines by underground or open pit mining. Natural uranium is a mixture of isotopes: uranium-238 (99.3%) and uranium-235 (0.7%). Since the main nuclear fuel is uranium-235, after primary processing, the ore enters the enrichment plant, where the content of uranium-235 in the ore is brought to 3–5%. Chemical processing of fuel consists in obtaining enriched uranium hexafluoride 235 UF 6 for the subsequent production of fuel rods (fuel elements).

The development of uranium deposits, like any other branch of the mining industry, worsens environment: Significant territories are being withdrawn from economic use, the landscape and hydrological regime are changing, air, soil, surface and ground waters are being polluted with radionuclides. The amount of radioactive waste at the stage of primary processing of natural uranium is very high and amounts to 99.8%. In Russia, mining and primary processing of uranium is carried out at only one enterprise - the Priargunsky Mining and Chemical Association. At all uranium ore mining and processing enterprises that have been operating until recently, 108 m 3 of radioactive waste with an activity of 1.8 10 5 Ci is located in dumps and tailings.

Fuel rods, which are metal rods containing nuclear fuel (3% uranium-235), are placed in the core of a nuclear power plant reactor. Various types of uranium-235 fission chain reactions are possible (difference in the resulting fragments and the number of emitted neutrons), for example, such:

235U+1 n ® 142 Ba + 91 Kr + 31 n,
235U+1 n ® 137 Te + 97 Zr + 21 n,
235U+1 n ® 140 Xe + 94 Sr + 21 n.

The heat released during the fission of uranium heats the water flowing through the core and washing the rods. After about three years, the content of uranium-235 in fuel rods drops to 1%, they become inefficient heat sources and need to be replaced. Each year, a third of the fuel rods are removed from the core and replaced with new ones: for a typical 1000 MW nuclear power plant, this means 36 tons of fuel rods removed annually.

During nuclear reactions fuel elements are enriched with radionuclides - fission products of uranium-235, as well as (through a series of b-decays) plutonium-239:

238U+1 n® 239 U(b ) ® 239 Np(b ) ® 239 Pu.

Spent fuel rods are transported from the core through an underwater channel to storage facilities filled with water, where they are stored in steel canisters for several months, until most of the highly toxic radionuclides (in particular, the most dangerous iodine-131) decay. After that, the fuel rods are sent to fuel regeneration plants, for example, to obtain plutonium cores for fast neutron nuclear reactors or weapons-grade plutonium.

Liquid waste from nuclear reactors (in particular, primary water, which must be renewed) after processing (evaporation) is placed in concrete storage facilities located on the territory of the nuclear power plant.

A certain amount of radionuclides during the operation of nuclear power plants is released into the air. Radioactive iodine-135 (one of the main decay products in an operating reactor) does not accumulate in spent nuclear fuel, since its half-life is only 6.7 hours, but as a result of subsequent radioactive decays it turns into xenon-135 radioactive gas, which actively absorbs neutrons and therefore preventing a chain reaction. To prevent "xenon poisoning" of the reactor, xenon is removed from the reactor through tall pipes.

The generation of waste at the stages of processing and storage of spent nuclear fuel has already been discussed. Unfortunately, all existing and applied methods of RW neutralization in the world (cementing, vitrification, bituminization, etc.), as well as solid RW incineration in ceramic chambers (as at NPO Radon in the Moscow Region) are ineffective and pose a significant danger to the environment. .

The problem of disposal and disposal of radioactive waste from nuclear power plants is becoming especially acute now, when it is time to dismantle the majority of nuclear power plants in the world (according to the IAEA 2 , these are more than 65 nuclear power plant reactors and 260 reactors used for scientific purposes). It should be noted that during the operation of a nuclear power plant, all elements of the plant become radioactively hazardous, especially the metal structures of the reactor zone. The dismantling of nuclear power plants in terms of cost and time is comparable to their construction, while there is still no acceptable scientific, technical and environmental technology for dismantling. An alternative to dismantling is sealing the station and protecting it for 100 years or more.

Even before the end of the fire at the Chernobyl nuclear power plant, the laying of a tunnel under the reactor began, the creation of a recess under it, which was then filled with a multi-meter layer of concrete. Both the block and the territories adjacent to it were poured with concrete - this is a “miracle of construction” (and an example of heroism without quotes) of the 20th century. called "sarcophagus". The exploding 4th power unit of the Chernobyl nuclear power plant is still the world's largest and most dangerous poorly equipped radioactive waste storage facility!

When using radioactive materials in medical and other research institutions, a significantly smaller amount of radioactive waste is generated than in the nuclear industry and the military-industrial complex - this is several tens of cubic meters of waste per year. However, the use of radioactive materials is expanding, and with it the volume of waste is increasing.

The problem of radioactive waste is an integral part of the “Agenda for the XXI century” adopted at the World Summit on the Earth in Rio de Janeiro (1992) and the “Action Program for the Further Implementation of the “Agenda for the XXI Century””, adopted by Special Session of the United Nations General Assembly (June 1997). The latter document, in particular, outlines a system of measures to improve the methods of radioactive waste management, to expand international cooperation in this area (exchange of information and experience, assistance and transfer of relevant technologies, etc.), to tighten the responsibility of states for ensuring safe storage and removal of radioactive waste.

The “Program of Action...” notes the deterioration of general trends in the field of sustainable development world, but it is hoped that by the next international environmental forum, scheduled for 2002, there will be tangible progress towards sustainable development aimed at creating favorable living conditions for future generations.

E.E. Borovsky

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1 All the data below are taken from materials of open publications in the state reports "On the state of the environment of the Russian Federation" State Committee Russian Federation for Environmental Protection and in the Russian environmental newspaper " Green World» (1995–1999).
2 International Agency on atomic energy.

Every production process leaves behind waste. And spheres that use the properties of radioactivity are no exception. Free circulation of nuclear waste, as a rule, is already unacceptable at the legislative level. Accordingly, they must be isolated and preserved, taking into account the characteristics of individual elements.

Sign, which is a warning about the danger of ionizing radiation of radioactive waste (radioactive waste)

Radioactive waste (RW) is a substance that contains elements that have radioactivity. Such wastes have no practical significance, that is, they are unsuitable for recycling.

Note! Quite often, a synonymous concept is used -.

From the term "radioactive waste" it is worth distinguishing the concept of "spent nuclear fuel - SNF". The difference between SNF and RW is that spent nuclear fuel after proper processing can be reused in the form of fresh materials for nuclear reactors.

Additional information: SNF is a collection of fuel elements, mainly consisting of fuel residues nuclear installations and a large number of half-life products, as a rule, they are isotopes 137 Cs and 90 Sr. They are actively used in the work of scientific and medical institutions as well as industrial and agricultural enterprises.

In our country, there is only one organization that has the right to carry out activities for the final disposal of radioactive waste. This is the National Operator for Radioactive Waste Management (FGUP NO RAO).

The actions of this organization are regulated by the Legislation of the Russian Federation (No. 190 FZ of July 11, 2011). The law prescribes the mandatory disposal of radioactive waste produced in Russia, and also prohibits their import from abroad.

Classification

The classification of the considered type of waste includes several classes of radioactive waste and consists of:

• low-level (they can be divided into classes: A, B, C and GTCC (the most dangerous));
• medium-level (in the United States, this type of radioactive waste is not allocated to a separate class, so the concept is usually used in European countries);
• highly active radioactive waste.

Sometimes one more class of radioactive waste is isolated: transuranic. TO this class belong to wastes characterized by the content of transuranium α-emitting radionuclides with long decay periods and extremely high values ​​of their concentrations. Due to the long half-life of these wastes, the burial is much more thorough than the isolation of low-level and medium-level radioactive waste. It is extremely problematic to predict how dangerous these substances will be for the environmental situation and the human body.

The problem of radioactive waste management

During the operation of the first enterprises using radioactive compounds, it was generally accepted that the dispersion of a certain amount of radioactive waste in areas of the environment is permissible, in contrast to the waste generated in other industrial sectors.

So, at the notorious Mayak enterprise on initial stage activities, all RW was discharged to the nearest water sources. Thus, there was a serious pollution of the Techa River and a number of reservoirs located on it.

Subsequently, it turned out that various fields biosphere, accumulation and concentration of hazardous radioactive waste occurs, and therefore their simple discharge into the environment is unacceptable. Together with contaminated food, radioactive elements enter the human body, which leads to a significant increase in the risk of exposure. Therefore, various methods of RW collection, transportation and storage have been actively developed in recent years.

Disposal and recycling

Disposal of radioactive waste can occur in different ways. It depends on the RAO class to which they belong. The most primitive is the disposal of low-level and medium-level radioactive waste. We also note that according to the structure, radioactive waste is divided into short-lived substances with a short half-life and waste with a long half-life. The latter belong to the class of long-lived.

For short-lived wastes, the easiest way to dispose of them is considered to be their short-term storage on specially designed sites in sealed containers. Within a certain time, radioactive waste is neutralized, after which radioactively harmless waste can be recycled in the same way as household waste. Such waste may include, for example, materials from medical institutions (HCF). A container for short-term storage can be a standard two-hundred-liter barrel made of metal. To avoid the penetration of radioactive elements from the tank into the environment, the waste is usually filled with a bituminous or cement mixture.

The photo shows the technologies for handling radioactive waste at one of the modern enterprises in Russia

Disposal of waste that is constantly generated at nuclear power plants is much more difficult to implement and requires the use of special methods, such as, for example, plasma processing, recently implemented at the Novovoronezh NPP. In this case, RW is subjected to transformation into substances similar to glass, which are subsequently placed in containers for the purpose of irretrievable disposal.

Such processing is absolutely safe and allows several times to reduce the amount of radioactive waste. This is facilitated by the multi-stage purification of combustion products. The process can run offline for 720 hours, with a productivity of up to 250 kg of waste per hour. The temperature indicator in the furnace installation at the same time reaches 1800 0 C. It is believed that such new complex will continue for another 30 years.

The advantages of the plasma process of radioactive waste disposal over others, as they say, are obvious. So, there is no need to carefully sort the waste. In addition, numerous cleaning methods can reduce the release of gaseous impurities into the atmosphere.

Radioactive Contamination, Radioactive Waste Repositories in Russia

For many years, Mayak, located in the northeastern part of Russia, was a nuclear power plant, but in 1957 one of the most catastrophic nuclear accidents occurred there. As a result of the incident, up to 100 tons of dangerous radioactive waste were released into the natural environment, affecting vast territories. At the same time, the catastrophe was carefully concealed until the 1980s. For many years, waste was dumped into the Karachay River from the station and from the polluted surrounding area. This has caused pollution of the water source, so necessary for thousands of people.

"Mayak" is far from the only place in our country subject to radioactive contamination. One of the main environmentally hazardous facilities in the Nizhny Novgorod region is a radioactive waste disposal site located 17 kilometers from the city of Semyonov, also commonly known as the Semyonovsky burial ground.

There is a storage facility in Siberia that has been storing nuclear waste for more than 40 years. To store radioactive materials, they use uncovered pools and containers, which already contain approximately 125,000 tons of waste.

In general, a huge number of territories have been discovered in Russia with levels of radiation exceeding the permissible norms. They even include such large cities as St. Petersburg, Moscow, Kaliningrad, etc. For example, in kindergarten near the Institute. Kurchatov in our capital, a sandbox for children with a radiation level of 612 thousand mR / h was identified. If a person were at this "safe" children's facility for 1 day, then he would be exposed to a lethal dose of radiation.

During the existence of the USSR, especially in the middle of the last century, the most dangerous radioactive waste could be dumped into the nearest ravines, so that a whole dump was formed. And with the growth of cities, new sleeping and industrial quarters were built in these infected places.

It is rather problematic to assess what is the fate of radioactive waste in the biosphere. Rains and winds actively spread pollution to all surrounding areas. Thus, in recent years, the rate at which the White Sea is polluted as a result of radioactive waste disposal has increased significantly.

Burial issues

There are two approaches to the implementation of nuclear waste storage and disposal processes today: local and regional. Disposal of radioactive waste at the site of their production is very convenient from different points of view, however, such an approach can lead to an increase in the number of hazardous disposal sites during the construction of new facilities. On the other hand, if the number of these places is strictly limited, then there will be a problem of cost and ensuring the safe transportation of waste. Indeed, regardless of whether the transportation of radioactive waste is a production process, it is worth eliminating non-existent hazard criteria. Making an uncompromising choice in this matter is quite difficult, if not impossible. In different states, this issue is solved in different ways and there is no consensus yet.

One of the main problems can be considered the definition of geological formations suitable for organizing a radioactive waste cemetery. Deep adits and mines used for the extraction of rock salt are best suited for this purpose. And also they often adapt wells in areas rich in clay and rock. High water resistance, one way or another, is one of the most important characteristics when choosing a burial site. A kind of burial ground for radioactive waste appears in the places of underground nuclear explosions. So, in the state of Nevada, USA, on a site that served as a test site for about 450 explosions, almost each of these explosions formed a repository of high-level nuclear waste buried in the rock without any technical "obstacles".

Thus, the problem of the formation of radioactive waste is extremely difficult and ambiguous. Achievements in nuclear energy, of course, bring enormous benefits to mankind, but at the same time they create a lot of trouble. And one of the main and unresolved problems today is the problem of disposal of radioactive waste.

More details about the history of the issue, as well as the modern view on the issue of nuclear waste, can be seen in the special issue of the program “Nuclear Legacy” of the TV channel “Science 2.0”.

After the prohibition of nuclear weapons tests in three areas, the problem of the destruction of radioactive waste generated in the process of using atomic energy for peaceful purposes occupies one of the first places among all problems of radiation ecology.

According to the physical state, radioactive waste (RW) is divided into solid, liquid and gaseous.

According to OSPORB-99 (Basic Sanitary Rules for Ensuring Radiation Safety), solid radioactive waste includes spent radionuclide sources, materials, products, equipment, biological objects, soil not intended for further use, as well as solidified liquid radioactive waste, in which the specific activity radionuclides are greater than the values ​​given in Appendix P-4 NRB-99 (radiation safety standards). With an unknown radionuclide composition, RW should include materials with a specific activity greater than:

100 kBq/kg for beta radiation sources;

10 kBq/kg - for sources of alpha radiation;

1 kBq/kg - for transuranium radionuclides (chemical radioactive elements located in the periodic system of elements after uranium, i.e. with an atomic number greater than 92. All of them are obtained artificially, and only Np and Pu are found in nature in extremely small quantities).

Liquid radioactive waste includes organic and inorganic liquids, pulps and sludges that are not subject to further use, in which the specific activity of radionuclides is more than 10 times higher than the intervention levels for entry with water given in Annex P-2 of NRB-99.

Gaseous radioactive waste includes radioactive gases and aerosols that are not subject to use and are formed during production processes with volumetric activity exceeding the allowable average annual volumetric activity (AVA) given in Appendix P-2 of NRB-99.

Liquid and solid radioactive wastes are subdivided according to their specific activity into 3 categories: low-level, medium-level and high-level (Table 26).

Table26 – Classification of liquid and solid radioactive waste (OSPORB-99)

Radioactive waste is generated:

− in the process of extraction and processing of radioactive mineral
raw materials;

− during operation of nuclear power plants;

− in the process of operation and disposal of ships with nuclear
installations;

− when reprocessing spent nuclear fuel;

- in the production of nuclear weapons;

− when carrying out scientific work using research
Telsky nuclear reactors and fissile material;

− when using radioisotopes in industry, copper
cine, science;

− during underground nuclear explosions.

The system for handling solid and liquid RW at the places of their generation is determined by the project for each organization planning work with open sources of radiation, and includes their collection, sorting, packaging, temporary storage, conditioning (concentration, solidification, pressing, incineration), transportation, long-term storage and burial.

For the collection of radioactive waste, the organization must have special collections. Collection locations should be provided protective devices to reduce radiation beyond them to an acceptable level.

Special protective wells or niches should be used for temporary storage of radioactive waste that creates a gamma radiation dose of more than 2 mGy/h near the surface.

Liquid radioactive waste is collected in special containers, after which it is sent for disposal. It is prohibited to discharge liquid RW into domestic and storm sewers, reservoirs, wells, wells, irrigation fields, filtration fields and onto the Earth's surface.

During nuclear reactions occurring in the reactor core, radioactive gases are released: xenon-133 (T physical. = 5 days), krypton-85 (T physical. = 10 years), radon-222 (T physical. = 3.8 days) and others. These gases enter the filter adsorber, where they lose their activity and only then are released into the atmosphere. Some carbon-14 and tritium are also released into the environment.

Another source of rhodionuclides released into the environment from operating nuclear power plants is unbalance and process water. Fuel elements located in the reactor core are often deformed and fission products enter the coolant. An additional source of radiation in the coolant are radionuclides formed as a result of irradiation of reactor materials with neutrons. Therefore, the water of the primary circuit is periodically renewed and cleaned from radionuclides.

In order to prevent environmental pollution, the water of all technological circuits of the NPP is included in the circulating water supply system (Fig. 8).

Nevertheless, part of the liquid effluents is discharged into the cooling reservoir available at each nuclear power plant. This reservoir is a weakly flowing basin (most often it is an artificial reservoir), so the discharge of liquids containing even a small amount of radionuclides into it can lead to dangerous concentrations. The discharge of liquid radioactive waste into cooling ponds is strictly prohibited by the Sanitary Rules. Only liquids in which the concentration of radioisotopes does not exceed the permissible limits can be sent to them. In addition, the amount of liquids discharged into the reservoir is limited by the allowable discharge rate. This norm is set in such a way that the impact of radionuclides on water users does not exceed the dose of 5´10 -5 Sv/year. The volumetric activity of the main radionuclides in the discharged water from NPPs in the European part of Russia, according to Yu.A. Egorova (2000), is (Bq):

Rice. 8. Structural scheme of NPP recycling water supply

In progress self-purification water, these radionuclides sink to the bottom and are gradually buried in bottom sediments where their concentration can reach 60 Bq/kg. Relative distribution of radionuclides in the ecosystems of NPP cooling ponds, according to Yu.A. Egorov is given in Table 27. According to this author, such reservoirs can be used for any national economic and recreational purposes.

Table 27 – Relative distribution of radionuclides in cooling ponds, %

Do nuclear power plants harm the environment? The operating experience of domestic nuclear power plants has shown that with proper maintenance and well-established environmental monitoring, they are practically safe. The radioactive impact on the biosphere of these enterprises does not exceed 2% of the local radiation background. Landscape and geochemical studies in the ten-kilometer zone of the Beloyarsk NPP show that the density of plutonium contamination of soils in forest and meadow biocenoses does not exceed 160 Bq/m2 and is within the global background (Pavletskaya, 1967). Calculations show that in terms of radiation, thermal power plants are much more dangerous, since the coal, peat and gas burned at them contain natural radionuclides of the uranium and thorium families. The average individual exposure doses in the area of ​​location of thermal power plants with a capacity of 1 GW/year are from 6 to 60 µSv/year, and from NPP emissions - from 0.004 to 0.13 µSv/year. Thus, nuclear power plants during their normal operation are more environmentally friendly than thermal power plants.

The danger of nuclear power plants lies only in accidental releases of radionuclides and their subsequent distribution in the external environment by atmospheric, water, biological and mechanical ways. In this case, damage is inflicted on the biosphere, disabling vast territories that long years cannot be used for business purposes.

So, in 1986, at the Chernobyl nuclear power plant, as a result of a thermal explosion, up to 10% of nuclear material was released into the environment,
located in the reactor core.

For the entire period of operation of nuclear power plants in the world, about 150 accidental cases of releases of radionuclides into the biosphere have been officially recorded. This is an impressive figure showing that the reserve for improving the safety of nuclear reactors is still quite large. Therefore, it is very important to monitor the environment in the areas of nuclear power plants, which plays a decisive role in the development of methods for localizing radioactive contamination and eliminating them. A special role here belongs to scientific research in the field of studying geochemical barriers, on which radioactive elements lose their mobility and begin to concentrate.

Radioactive waste containing radionuclides with a half-life of less than 15 days is collected separately and kept in temporary storage areas to reduce activity to safe levels, after which it is disposed of as normal industrial waste.

Transfer of radioactive waste from the organization for processing or disposal should be carried out in special containers.

Processing, long-term storage and disposal of radioactive waste is carried out by specialized organizations. IN individual cases it is possible to carry out all stages of RW management in one organization, if it is provided for by the project or a special permit is issued for this by the state supervision bodies.

The effective exposure dose to the public due to radioactive waste, including the stages of storage and disposal, should not exceed 10 µSv/year.

The largest volume of radioactive waste is supplied by nuclear power plants. Liquid radioactive waste from nuclear power plants is the distillation residues of evaporators, pulp from mechanical and ion-exchange filters for the purification of contour water. At nuclear power plants, they are stored in concrete tanks lined with stainless steel. Then they are cured and buried using a special technology. TO solid waste Nuclear power plants include failed equipment and its parts, as well as consumable materials. As a rule, they have low activity and are disposed of at nuclear power plants. Waste with medium and high activity is sent for disposal in special underground storage facilities.

Storage facilities for radioactive waste are located deep underground (at least 300 m), and they are constantly monitored, since radionuclides emit a large amount of heat. Underground RW storage facilities should be long-term, designed for hundreds and thousands of years. They are located in seismically calm areas, in homogeneous rock masses devoid of cracks. The most suitable for this are granite geological complexes of mountain ranges adjacent to the ocean coast. It is most convenient to build underground tunnels for radioactive waste in them (Kedrovsky, Chesnokov, 2000). Reliable RW storage facilities can be located in permafrost. One of them is planned to be created on Novaya Zemlya.

To facilitate disposal and reliability of the latter, liquid highly active radioactive waste is converted into solid inert substances. Currently, the main methods of processing liquid radioactive waste are cementing and vitrification followed by confinement in steel containers, which are stored underground at a depth of several hundred meters.

Researchers of the Moscow Association "Radon" proposed a method for converting liquid radioactive waste into stable aluminosilicate ceramics at a temperature of 900°C using urea (urea), fluorine salts and natural aluminosilicates (Lashchenova, Lifanov, Solovyov, 1999).

However, for all their progressiveness, the listed methods have a significant drawback - the volumes of radioactive waste are not reduced. Therefore, scientists are constant search other methods of disposal of liquid RW. One of such methods is the selective sorption of radionuclides. As sorbents researchers suggest using natural zeolites, which can be used to purify liquids from radioisotopes of cesium, cobalt and manganese to safe concentrations. At the same time, the volume of the radioactive product is reduced tenfold (Savkin, Dmitriev, Lifanov et al., 1999). Yu.V. Ostrovsky, G.M. Zubarev, A.A. Shpak and other Novosibirsk scientists (1999) proposed a galvanochemical
processing of liquid radioactive waste.

A promising method for the disposal of high-level waste is to remove them into space. The method was proposed by Academician A.P. Kapitsa in 1959. Intensive research is currently underway in this area.

Radioactive waste is produced in large quantities by nuclear power plants, research reactors and the military (nuclear reactors of ships and submarines).

According to the IAEA, by the end of 2000, 200,000 tons of irradiated fuel had been unloaded from nuclear reactors.

It is assumed that the main part of it will be removed without processing (Canada, Finland, Spain, Sweden, USA), the other part will be processed (Argentina, Belgium, China, France, Italy, Russia, Switzerland, England, Germany).

Belgium, France, Japan, Switzerland, England bury blocks with radioactive waste enclosed in borosilicate glass.

Burial at the bottom of the seas and oceans. Disposal of radioactive waste in the seas and oceans was practiced by many countries. The United States did it first in 1946, then Great Britain in 1949, Japan in 1955, and the Netherlands in 1965. The first marine repository for liquid radioactive waste appeared in the USSR no later than 1964.

In marine burials of the North Atlantic, where, according to the IAEA, from 1946 to 1982, 12 countries of the world flooded radioactive waste with a total activity of more than MKi (one megaCurie). The regions of the globe in terms of total activity are now distributed as follows:

a) North Atlantic - approximately 430 kCi;

b) the seas of the Far East - about 529 kCi;

c) Arctic - does not exceed 700 kCi.

25-30 years have passed since the first flooding of high-level waste in the Kara Sea. Over the years, the activity of reactors and spent fuel has naturally decreased many times over. At present, the total RW activity in the northern seas is 115 kCi.

At the same time, it must be assumed that competent people, professionals in their field, were engaged in marine burials of radioactive waste. RW was flooded in the depressions of the bays, where these deep layers are not affected by currents and underwater waters. Because radioactive waste "sits" there and does not spread anywhere, but is only absorbed by special precipitation.

It should also be taken into account that radioactive waste with the highest activity is conserved by hardening mixtures. But even if radionuclides get into sea ​​water- they are sorbed by these sediments in the immediate vicinity of the flooded object. This was confirmed by direct measurements of the radiation situation.

The most frequently discussed possibility for radioactive waste disposal is the use of disposal facilities in a deep basin, where the average depth is at least 5 km. The deep rocky ocean floor is covered with a layer of sediment, and a shallow burial under tens of meters of sediment can be obtained by simply dropping the container overboard. A deep burial under hundreds of meters of sediment would require drilling and waste disposal. The sediments are saturated with sea water, which after tens or hundreds of years can corrode (by corrosion) fuel cell canisters from used fuel. However, it is assumed that the sediments themselves adsorb leached fission products, preventing them from entering the ocean. Calculations of the consequences of the extreme case of the destruction of the container shell immediately after falling into the sediment layer showed that the dispersion of the fuel element containing fission products under the sediment layer will occur no earlier than in 100-200 years. By that time, the level of radioactivity will drop by several orders of magnitude.

Final burial in salt deposits. Salt deposits are attractive sites for long-term disposal of radioactive waste. The fact that the salt is in solid form in the geological layer indicates that there has been no circulation of groundwater since its formation several hundred million years ago. Thus, the fuel placed in such a deposit will not be subject to leaching by groundwater.
waters. Salt deposits of this type are very common.

Geological burial. Geological disposal involves placing containers containing spent fuel elements in a stable bed, typically at a depth of 1 km. It can be assumed that such rocks contain water, since the depth of their occurrence is much lower than the groundwater table. However, water is not expected to play a major role in heat transfer from the containers, so the storage should be designed to keep the surface temperature of the canisters at or below 100°C or so. However, the presence of groundwater means that material leached from stored blocks may infiltrate the formation with water. This is an important issue in the design of such systems. The circulation of water through the rock as a result of the density difference caused by the temperature gradient over a long period of time is important in determining the migration of fission products. This process is very slow and therefore not expected to cause major trouble. However, for long-term disposal systems, it must necessarily be taken into account.

The choice between different disposal methods will be determined by the availability of convenient sites, and much more biological and oceanographic data will be needed. However, studies in many countries show that used fuel can be processed and disposed of without undue risk to humans and the environment.

IN Lately the possibility of throwing containers with long-lived isotopes using rockets to the invisible far side of the moon is being seriously discussed. That's just how to provide a 100% guarantee that all launches will be successful, not one of the launch vehicles will explode in the earth's atmosphere and will not cover it with deadly ash? No matter what the rocket men say, the risk is very high. And in general, we do not know why our descendants will need the far side of the Moon. It would be extremely frivolous to turn it into a murderous radiation dump.

Burial of plutonium. In the autumn of 1996, the International Scientific Seminar on Plutonium was held in Moscow. This extremely toxic substance is obtained from the operation of a nuclear reactor and was previously used to manufacture nuclear weapons. But over the years of using nuclear energy, thousands of tons of plutonium have already accumulated on Earth, no country needs so much for the production of weapons. So the question arose, what to do with it next?

Leaving it just like that somewhere in storage is a very expensive pleasure.

As you know, plutonium does not occur in nature, it is obtained artificially from uranium-238 by irradiating the latter with neutrons in a nuclear reactor:

92 U 238 + 0 n 1 -> -1 e 0 + 93 Pu 239 .

Plutonium has 14 isotopes with mass numbers ranging from 232 to 246; the most common isotope is 239 Pu.

Plutonium separated from nuclear power plant spent fuel contains a mixture of highly active isotopes. Under the action of thermal neutrons, only Pu-239 and Pu-241 are fissioned, while fast neutrons cause the fission of all isotopes.

The half-life of 239 Pu is 24000 years, 241 Pu is 75 years, and the isotope 241 Am is formed with strong gamma radiation. The toxicity is such that a thousandth of a gram causes death.

Academician Yu. Trutnev proposed to store plutonium in underground storage facilities constructed with the help of nuclear explosions. Radioactive waste, together with rocks, vitrifies and does not spread into the environment.

It is considered promising that spent nuclear fuel (SNF) is the most valuable tool for the nuclear industry, subject to processing and use in a closed cycle: uranium - reactor - plutonium - processing - reactor (England, Russia, France).

In 2000, Russian NPPs accumulated about 74,000 m 3 of liquid RW with a total activity of 0.22´10 5 Ci, about 93,500 m 3 of solid RW with an activity of 0.77´10 3 Ci, and about 9,000 tons of spent nuclear fuel with an activity of more than 4´10 9 Key. At many nuclear power plants, radioactive waste storage facilities are 75% full and the remaining volume will be enough for only 5-7 years.

Not a single nuclear power plant is equipped with equipment for conditioning the resulting radioactive waste. In the opinion of specialists from the Ministry of Atomic Energy of Russia, in the next 30-50 years, RW will actually be stored on the territory of nuclear power plants, so there is a need to create special long-term storage facilities there, adapted for the subsequent extraction of RW from them for transporting them to the final disposal site.

Liquid radioactive waste of the Navy is stored in coastal and floating tanks in the regions where ships with nuclear engines are based. The annual inflow of such RW is about 1300 m 3 . They are processed by two technical transport vessels (one in the Northern Fleet, the other in the Pacific Fleet).

In addition, due to the intensification of the use of ionizing radiation in human economic activities, the volume of spent radioactive sources from enterprises and institutions that use radioisotopes in their work increases every year. Most of these enterprises are located in Moscow (about 1000), regional and republican centers.

This category of radioactive waste is disposed of through the centralized system of territorial special plants "Radon" of the Russian Federation, which receive, transport, process and dispose of spent sources of ionizing radiation. The Department of Housing and Communal Services of the Ministry of Construction of the Russian Federation controls 16 Radon special plants: Leningrad, Nizhny Novgorod, Samara, Saratov, Volgograd, Rostov, Kazan, Bashkir, Chelyabinsk, Yekaterinburg, Novosibirsk, Irkutsk, Khabarovsk, Primorsky, Murmansk, Krasnoyarsk. The seventeenth special plant, Moscow (located near the city of Sergiev Posad), is subordinate to the Government of Moscow.

Each Radon enterprise has specially equipped radioactive waste disposal sites(PZRO).

For disposal of spent sources of ionizing radiation, well-type engineering near-surface storage facilities are used. Each Radon enterprise has a normal
operation of storage facilities, accounting of buried waste, permanent radiation control and monitoring of the radioecological state of the environment. Based on the results of monitoring the radioecological situation in the RWDF location area, a radioecological passport of the enterprise is periodically compiled, which is approved by the control and supervisory authorities.

Special plants "Radon" were designed in the 70s of the XX century in accordance with the requirements of now obsolete radiation safety standards.

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In the 20th century, the non-stop search for the ideal source of energy seemed to be over. This source was the nuclei of atoms and the reactions taking place in them - the active development of nuclear weapons and the construction of nuclear power plants began all over the world.

But the planet quickly faced the problem of processing and destroying nuclear waste. The energy of nuclear reactors carries a lot of dangers, as well as the waste of this industry. Until now, there is no carefully developed processing technology, while the sphere itself is actively developing. Therefore, safety depends primarily on proper disposal.

Definition

Nuclear waste contains radioactive isotopes of certain chemical elements. In Russia, according to the definition given in the Federal Law No. 170 “On the Use of Atomic Energy” (dated November 21, 1995), further use of such waste is not envisaged.

The main danger of materials lies in the radiation of gigantic doses of radiation, which has a detrimental effect on a living organism. The consequences of radioactive exposure are genetic disorders, radiation sickness and death.

Classification map

The main source of nuclear materials in Russia is the sphere of nuclear energy and military developments. All nuclear waste has three degrees of radiation, familiar to many from the course of physics:

• Alpha - radiant.
• Beta - emitting.
• Gamma - emitting.

The former are considered the most harmless, as they give a harmless level of radiation, unlike the other two. True, this does not prevent them from being included in the class of the most hazardous waste.


In general, the classification map of nuclear waste in Russia divides it into three types:

1. Solid nuclear waste. This includes a huge amount of maintenance materials in the energy sector, personnel clothing, garbage that accumulates in the course of work. Such waste is burned in kilns, after which the ashes are mixed with a special cement mixture. It is poured into barrels, sealed and sent to storage. The burial is detailed below.
2. Liquid. The process of operation of nuclear reactors is impossible without the use of technological solutions. In addition, this includes water that is used to treat special suits and wash workers. Liquids are carefully evaporated, and then burial occurs. Liquid waste is often recycled and used as fuel for nuclear reactors.
3. Elements of the design of reactors, transport and means of technical control at the enterprise constitute a separate group. Their disposal is the most expensive. To date, there are two ways out: installation of the sarcophagus or dismantling with its partial decontamination and further shipment to the repository for burial.

The map of nuclear waste in Russia also defines low-level and high-level:

• Low-level waste - arise in the course of the activities of medical institutions, institutes and research centers. Here, radioactive substances are used to conduct chemical tests. The level of radiation emitted by these materials is very low. Proper Disposal allows you to turn hazardous waste into normal waste in about a few weeks, after which it can be disposed of as normal waste.
• High-level waste is spent reactor fuel and materials used in the military industry to develop nuclear weapons. The fuel at the stations is a special rod with a radioactive substance. The reactor operates for approximately 12-18 months, after which the fuel must be changed. The amount of waste is simply enormous. And this figure is growing in all countries developing the field of nuclear energy. The disposal of high-level waste must take into account all the nuances in order to avoid a catastrophe for the environment and humans.

Recycling and disposal

On this moment There are several methods for the disposal of nuclear waste. All of them have their advantages and disadvantages, but whatever one may say, they do not completely eliminate the danger of radioactive exposure.

burial

Waste disposal is the most promising method of disposal, which is especially actively used in Russia. First, the process of vitrification or "vitrification" of the waste occurs. The spent substance is calcined, after which quartz is added to the mixture, and this “liquid glass” is poured into special cylindrical steel molds. The resulting glass material is resistant to water, which reduces the possibility of radioactive elements entering the environment.

Finished cylinders are brewed and thoroughly washed, getting rid of the slightest contamination. Then they go to storage for a very long time. The repository is arranged in geologically stable areas so that the repository is not damaged.

Geological disposal is carried out at a depth of more than 300 meters in such a way that for a long time the waste does not need further maintenance.

Burning

Part of the nuclear materials, as mentioned above, is the direct results of production, and a kind of side waste in the energy sector. These are materials exposed to radiation during production: waste paper, wood, clothing, household waste.

All this is burned in specially designed furnaces, which minimize the level of toxic substances in the atmosphere. The ash, among other wastes, is cemented.

Cementing

Disposal (one of the ways) of nuclear waste in Russia by cementing is one of the most common practices. The bottom line is to place irradiated materials and radioactive elements in special containers, which are then filled with a special solution. The composition of such a solution includes a whole cocktail of chemical elements.

As a result, it is practically not exposed to the external environment, which makes it possible to achieve an almost unlimited period. But it is worth making a reservation that such a burial is possible only for the disposal of waste of an average level of danger.

Seal

A long and fairly reliable practice aimed at burying and reducing the amount of waste. It is not applicable to the processing of basic fuel materials, but allows the processing of other low-hazard wastes. This technology uses hydraulic and pneumatic presses with low pressure force.

Reapplication

The use of radioactive material in the field of energy is not fully implemented due to the specific nature of the activity of these substances. Once exhausted, the waste still remains a potential source of energy for reactors.

IN modern world and even more so in Russia, the situation with energy resources is quite serious, and therefore the recycling of nuclear materials as fuel for reactors no longer seems unbelievable.

Today, there are methods that allow the use of spent raw materials for applications in the energy sector. The radioisotopes contained in the waste are used to process food products and as a "battery" for the operation of thermoelectric reactors.

But while the technology is still in development, and the ideal method of processing has not been found. Nevertheless, the processing and destruction of nuclear waste makes it possible to partially resolve the issue with such garbage, using it as fuel for reactors.

Unfortunately, in Russia, a similar method of getting rid of nuclear debris is practically not being developed.

Volumes

In Russia, all over the world, the volumes of nuclear waste sent for disposal amount to tens of thousands of cubic meters annually. Every year, European storage facilities receive about 45,000 cubic meters of waste, while in the United States, only one landfill in Nevada absorbs such a volume.

Nuclear waste and work related to it abroad and in Russia is the activity of specialized enterprises equipped with high-quality machinery and equipment. In factories, waste is different ways processing described above. As a result, it is possible to reduce the volume, reduce the level of danger, and even use some waste in the energy sector as fuel for nuclear reactors.

The peaceful atom has long proved that everything is not so simple. The energy sector is developing and will continue to develop. The same can be said about the military sphere. But if we sometimes turn a blind eye to the release of other wastes, improperly disposed of nuclear waste can cause a total catastrophe for all mankind. Therefore, this issue needs to be resolved as soon as possible before it is too late.

Connoisseurs appreciate Fourier's champagne. It is obtained from grapes grown in the picturesque hills of Champagne. It is hard to believe that less than 10 km from the famous vineyards is the largest repository of radioactive waste. They are brought from all over France, delivered from abroad and buried for the next hundreds of years. Fourier's house continues to make excellent champagne, meadows are blooming around, the situation is controlled, complete cleanliness and safety is guaranteed on and around the site. Such a green lawn is the main purpose of the construction of radioactive waste disposal sites.

Roman Fishman

Whatever some hotheads may say, it is safe to say that Russia is not in danger of becoming a global radioactive dump in the foreseeable future. A federal law passed in 2011 expressly prohibits the transportation of such waste across the border. The ban works both ways, with the only exception relating to the return of radiation sources that were produced in the country and shipped abroad.

But even with the law in place, there is little that is truly scary waste in the nuclear industry. Spent nuclear fuel (SNF) contains the most active and dangerous radionuclides: fuel elements and assemblies in which they are placed radiate even more than fresh nuclear fuel and continue to release heat. This is not waste, but a valuable resource, it contains a lot of uranium-235 and 238, plutonium and a number of other isotopes useful for medicine and science. All this makes up more than 95% of SNF and is successfully recovered at specialized enterprises - in Russia, this is primarily the famous Mayak Production Association in the Chelyabinsk Region, where the third generation of reprocessing technologies is now being introduced, which makes it possible to return 97% of SNF to work. Soon, the production, operation and processing of nuclear fuel will be closed in a single cycle that does not produce practically any hazardous substances.

However, even without SNF, the volumes of radioactive waste will amount to thousands of tons per year. After all, sanitary rules require that everything that emits above a certain level or contains more than the prescribed amount of radionuclides be included here. Almost any object that has been in contact with ionizing radiation for a sufficiently long time falls into this group. Parts of cranes and machines that worked with ore and fuel, air and water filters, wires and equipment, empty containers and just overalls that have served their time and no longer have value. The IAEA (International Atomic Energy Agency) divides radioactive waste (RW) into liquid and solid, of several categories, ranging from very low level to high level. And each has its own set of requirements.

Cold: recycling

The biggest environmental mistakes associated with the nuclear industry were made in the early years of the industry. Still not imagining all the consequences, the superpowers of the mid-twentieth century were in a hurry to get ahead of their competitors, to master the power of the atom more fully and did not pay much attention to waste management. However, the results of such a policy became apparent quite soon, and already in 1957 the USSR adopted a resolution “On measures to ensure safety when working with radioactive substances”, and a year later the first enterprises for their processing and storage were opened.

Some of the enterprises are still operating, already in the structures of Rosatom, and one retains its old "serial" name - "Radon". A dozen and a half enterprises were transferred to the management of a specialized company, RosRAO. Together with the Mayak Production Association, the Mining and Chemical Combine and other enterprises of Rosatom, they are licensed to handle radioactive waste of various categories. However, not only nuclear scientists resort to their services: radioactive substances are used for a variety of tasks, from cancer treatment and biochemical research to the production of radioisotope thermoelectric generators (RTGs). And all of them, having fulfilled their own, turn into waste.

Most of them are low activity - and of course, over time, as short-lived isotopes decay, they become safer. Such waste is usually sent to prepared landfills for storage for tens or hundreds of years. They are pre-processed: what can burn is burned in furnaces, cleaning the smoke complex system filters. Ashes, powders and other loose components are cemented or poured with molten borosilicate glass. Liquid waste of moderate volumes is filtered and concentrated by evaporation, extracting radionuclides from them with sorbents. The hard ones are crushed in the presses. Everything is placed in 100- or 200-liter barrels and pressed again, placed in containers and once again cemented. “Everything is very strict here,” the deputy told us. CEO RusRAO Sergey Nikolaevich Brykin. “Everything that is not permitted by licenses is prohibited in the handling of radioactive waste.”

For the transportation and storage of radioactive waste, special containers are used: depending on the activity and type of radiation, they can be reinforced concrete, steel, lead, or even boron-enriched polyethylene. Processing and packaging are trying to be done on site using mobile complexes in order to reduce the difficulties and risks of transportation, partly with the help of robotic technology. Transportation routes are thought out and agreed in advance. Each container has its own identifier, and their fate is traced to the very end.

RW conditioning and storage center in Andreeva Bay on the shore Barents Sea works on the site of the former technical base of the Northern Fleet.

Warmer: storage

RITEGs, which we mentioned above, are almost never used on Earth today. Once they provided power for automatic monitoring and navigation points in distant and hard-to-reach places. However, numerous incidents with leaks of radioactive isotopes into the environment and the banal theft of non-ferrous metal forced them to abandon their use anywhere other than spacecraft. In the USSR, they managed to produce and assemble more than a thousand RTGs, which have been dismantled and continue to be disposed of.

More big problem represents the legacy of the Cold War: over the decades, almost 270 nuclear submarines alone were built, and today less than fifty remain in service, the rest are disposed of or awaiting this complex and expensive procedure. At the same time, the spent fuel is unloaded, and the reactor compartment and two neighboring ones are cut out. Equipment is dismantled from them, additionally sealed and left to be stored afloat. This has been done for years, and by the beginning of the 2000s, about 180 radioactive “floats” were rusting in the Russian Arctic and the Far East. The problem was so acute that it was discussed at a meeting of the leaders of the G8 countries, who agreed on international cooperation in cleaning the coast.

Dock-pontoon for operations with reactor compartment blocks (85 x 31.2 x 29 m). Carrying capacity: 3500 t; towing draft: 7.7 m; towing speed: up to 6 knots (11 km/h); service life: at least 50 years. Builder: Fincantieri. Operator: Rosatom. Location: Saida Guba in the Kola Bay, designed to store 120 reactor compartments.

Today, blocks are lifted from the water and cleaned, reactor compartments are cut out, and an anti-corrosion coating is applied to them. The processed packages are installed for long-term safe storage on prepared concrete sites. At the recently launched complex in Saida Guba in Murmansk region for this, they even demolished a hill, the rocky foundation of which provided a reliable support for the storage, designed for 120 compartments. Lined up in a row, heavily colored reactors resemble a neat factory site or warehouse. industrial equipment, which is monitored by an attentive owner.

Such a result of the liquidation of dangerous radiation objects is called “brown lawn” in the language of nuclear scientists and is considered completely safe, although not very aesthetic in appearance. The ideal target of their manipulations is a “green lawn”, similar to the one that stretches over the already familiar French CSA (Centre de stockage de l’Aube) storage facility. A waterproof coating and a thick layer of specially selected turf turn the roof of a buried bunker into a clearing in which you want to lie down, especially since it is allowed. Only the most dangerous radioactive waste is destined not for a “lawn”, but for the gloomy darkness of the final disposal.

Hot: Burial

High-level radioactive waste, including SNF processing waste, needs reliable isolation for tens and hundreds of thousands of years. Sending waste into space is too expensive, dangerous for launch accidents, and dumping it in the ocean or in cracks in the earth's crust is fraught with unpredictable consequences. For the first years or decades, they can still be kept in the pools of “wet” above-ground storages, but then something will have to be done with them. For example, to transfer to a safer and more durable dry place and guarantee its reliability for hundreds and thousands of years.

“The main problem of dry storage is heat transfer,” Sergey Brykin explains. - If not aquatic environment, high-level waste is heated, which requires special engineering solutions.” In Russia, such a centralized above-ground storage facility with a well-thought-out passive air cooling system operates at the Mining and Chemical Combine near Krasnoyarsk. But this is only a half-measure: a truly reliable repository should be underground. Then it will be protected not only by engineering systems, but also by geological conditions, hundreds of meters of immovable and preferably waterproof rock or clay rock.

Such an underground dry storage facility has been in use since 2015 and continues to be built in Finland in parallel. In Onkalo, highly active RW and SNF will be locked up in a granite rock at a depth of about 440 m, in copper canisters, additionally insulated with bentonite clay, and for a period of at least 100 thousand years. In 2017, the Swedish power engineers from SKB announced that they would adopt this method and build their own "eternal" storage near Forsmark. Debate continues in the US over the construction of the Yucca Mountain repository in the Nevada desert, which will extend hundreds of meters into a volcanic mountain range. The general craze for underground storage can be seen from the other side: such a reliable and secure burial can be good business.

Taryn Simon, 2015-3015. Glass, radioactive waste. Vitrification of radioactive waste seals it inside a solid inert substance for millennia. American artist Taryn Simon used this technology in her work dedicated to the centenary of Malevich's Black Square. The black glass cube with vitrified radioactive waste was created in 2015 for the Garage Museum in Moscow and has since been stored at the Radon plant in Sergiev Posad. It will enter the museum in about a thousand years, when it will finally be safe for the public.

From Siberia to Australia

First, in the future technologies may require new rare isotopes, which are abundant in SNF. There may also be methods for their safe, cheap extraction. Secondly, many countries are ready to pay for the disposal of high-level waste right now. Russia, on the other hand, has nowhere to go: a highly developed nuclear industry needs a modern “eternal” repository for such dangerous radioactive waste. Therefore, in the mid-2020s, an underground research laboratory should start operating near the Mining and Chemical Combine.

Three vertical shafts will go into the gneiss rock, which is poorly permeable to radionuclides, and a laboratory will be equipped at a depth of 500 m, where canisters with electrically heated simulators of radioactive waste packages will be placed. In the future, compacted medium- and high-level waste, placed in special packages and steel canisters, will be placed in containers and cemented with a mixture based on bentonite. In the meantime, about one and a half hundred experiments are planned here, and only after 15-20 years of testing and safety validation, the laboratory will be converted into a long-term dry storage facility for radioactive waste of the first and second classes - in a sparsely populated part of Siberia.

The population of the country is an important aspect of all such projects. People rarely welcome the creation of radioactive waste disposal sites a few kilometers from own house, and in densely populated Europe or Asia it is not easy to find a place to build. Therefore, they are actively trying to interest such sparsely populated countries as Russia or Finland. Recently, Australia has joined them with its rich uranium mines. According to Sergei Brykin, the country has put forward a proposal to build an international repository on its territory under the auspices of the IAEA. The authorities expect that this will bring additional money and new technologies. But then Russia is definitely not in danger of becoming a global radioactive dump.

The article “Green lawn over the atomic burial ground” was published in the journal Popular Mechanics (No. 3, March 2018).