In 1948, the PO Prydneprovskiy Chemical Plant (initial name - Slag Fertilizers Plant) started production of uranium salts out of slag obtained during uranium and iron bearing ores melting in the blast-furnace No 6 of the metallurgical plant named after Dzerzhinskiy.
Except for uranium salts and their process liquors of the uranium production, mineral fertilizers and sodium nitrate were obtained, while nitrate and ammonium nitrogen from the production were utilized in the workshop No 3 of the Production Association (PA) AZOT in order to obtain nitrogen fertilizers.
Such process layout was in place up to the year 1963, when blast-furnace remelting of uranium and iron bearing ores was ceased. Subsequently uranium salts were extracted only from uranium ore and concentrates delivered from the republics of the USSR, Comecon countries, France and Spain.
The PA PCP operated in strict secrecy. Only ten years ago there was the opportunity to obtain limited information about the radioecological situation resulted from the plant’s operation. First actions were taken to provide for the radioecological safety then. In addition, at the time of the most vigorous activities of the plant, normative and technical documentation, containing the rules of radioactive wastes (RAW) management was not available.
Therefore, generated radioactive wastes were stored in the gullies or clay pits directly in the plant’s territory. First organized storages, for example Dneproskoye storage, were not equipped with the special water-proof protection system and were located in Dnieper’s flood plain.
By now, these radioactive waste tailings ponds are a real risk of the radioactive impurity of the environment.
The following tailings ponds are located within the territory of the Production Association Prydneprovskiy Chemical Plant:
Tailings pond Centralniy Yar, which was in operation from 1949 to 1954. It is located in the dammed gully. The tailings pond contains 200 thousand tons of solid radioactive waste with the volume 0,1 million cubic meters and area of 24 thousand square meters. Maximum capacity of the gamma ray doze is 4400 micro-roentgen per hour, total activity is 2800 Ku. The tailings pond is shut off with man-made land.
Tailings pond Zapadnoye, which was in operation from 1951 to 1954. It contains 800 thousand tons of solid radioactive waste with the volume 0,35 million cubic meters. Area is 60 thousand square meters. Maximum capacity of the gamma ray doze is 2500 micro-roentgen per hour, total activity is 4900 Ku.
Tailings pond Yugo-Vostochnoye, which was in operation from 1956 to 1980. It is located in the gully. It contains 300 thousand tons of solid radioactive waste with the volume 0,15 million cubic meters, area – 18 thousand square meters. Maximum gamma ray doze is 2300 micro-roentgen per hour. Total activity is 1800 Ku.
Territory and facilities of the PA PCP
As a result of the production activity related to uranium raw material reprocessing, some industrial buildings of workshops with installed equipment were radioactively contaminated. Gamma-radiation intensity in the workshops ranges from 100 to 30000 micro-roentgen per hour. The southern industrial site of the plant is the most contaminated. Not only are the workshops contaminated, but also storages, communications and the whole territory. The above stated tailings ponds are located there as well. The plant’s area with surface pollutant level exceeding natural background twice and more times, covers 635 thousand square meters; the exposition dose exceeding 100 micro-roentgen per hour covers about 250 thousand square meters of the territory. The volume of contaminated soil is over 400 thousand tons; total activity is about 760 Ku.
Pulp pipe line
The length of the radioactive waste pulp pipe from the PA PCP to the tailings pond Sukhachevskoye is more than 18 km. During over than 30 years of its operation and corrosion, there were numerous integrity damages and pulp spillages resulted in radioactive ground contamination along the pulp pipe route. Gamma radiation exposure doze rate exceeds 30 micro-roentgen per hour. An exact pulp pipe line grid is not available. At present, the pulp pipe line is cut out and taken to an undisclosed location.
117 local radiation pollution focuses are detected in Dneprodzerzhinsk city, where the exposure doze rate exceeds the norm several times.
The focuses originated subsequent to the use of slug of dumps of Dneprovskiy Metallurgical Combine (DMC) as construction materials, first of all, in the road building. The area of these local focuses is not big – to 10 square meters of the exposure doze boundary from 100 to 1000 micro-roentgen per hour. Radiation pollution of the area covering Lazo Street and Anoshkin Avenue, where Spornoye tailings pond is located, requires special examination.
Within the territory of Dneprodzerzhinsk the tailings pond Dneprovskoye is located, which was in operation from 1954 to 1968. It contains over 12 million tons of solid radioactive waste with the volume 5,84 million cubic meters. The area of the tailings pond is 730 thousand square meters. Maximum gamma ray doze is 1300 micro-roentgen per hour, total activity – 17000 Ku. The tailings pond is situated on Konoplyanka river bank, Dnieper flood-plane. The tailings dam is made out of the coking plant’s wastes with the top covered by uneven layer of phosphogypsum from 2 to 19 meters.
Tailings pond Lazo (Spornoye) is located near Lazo Street and Anoshkin Avenue. It contains radioactive waste of the DPA AZOT due to the reprocessing of nitrate solutions of the PA PCP to mineral fertilizers. Exact waste volume and its activity are not identified.
Base S is located within the territory of Dnepropetrovskiy district (former uranium ore storage). It was in operation from 1960 to 1991. It is located near the station Sukhachevka and contains 150-300 thousand of solid radioactive waste as half-ruined bins for uranium ore, contaminated railways, surface and under bins ground. The volume is 0,15 million cubic meters, area – 300 thousand square meters. Surface maximum gamma ray doze is 4700 micro-roentgen per hour, total activity – 12000 Ku.
Tailings pond Sukhachevskoye, S – 1 section was in operation from 1986 to 1983. It is situated apically Rosselevataya gully near the urban village Taromskoye. It contains 19 million tons of radioactive waste with the volume 8,5 million cubic meters and area 600 thousand square meters. Maximum gamma ray doze is 1600 micro-roentgen per hour, total activity – 18500 Ku.
Tailings pond Sukhachevskoye, S – 2 section is being operated from 1983. It contains 9,6 million tons of radioactive wastes. Spent slurry partially covers the surface (3-4 meters) of the tailings pond, mainly comprised of phosphogypsum. The volume is 3,7 million cubic meters, area – 390 thousand square meters. Surface maximum gamma ray doze comprises 500 micro-roentgen per hour, total activity – 8000 Ku.
Tailings pond of lanthanum particle was in operation in 1980 – 1990. It is located near the tailings pond Sukhachevskoye and contains 6600 tons of solid radioactive wastes. The volume is 3,3 thousand cubic meters, area – 0,6 thousand square meters. Surface maximum gamma ray doze comprises 3000 micro-roentgen per hour, total activity – 3600 Ku. The tailings pond had been suspended.
Tailings pond of the blast-furnace No 6 has been operating beginning from 1982. It is located in the territory of the Base S. The tailings pond contains 40 thousand tons of solid radioactive wastes as the disassembled at the DMC constructions and refractory, as well as the disassembled blast-furnace No 6. The volume is 20 thousand cubic meters, area – 2000 square meters. Surface maximum gamma ray doze comprises 4700 micro-roentgen per hour, total activity – 12000 Ku. The tailings pond is shut off with made ground.
One of the fugitive sources of the radiation pollution of environment is slag dumps burial at the DMC, rest of two capital repairs of the blast-furnace BF No 6 and blast-furnace cinder overflows. The volume of these radioactive wastes, their total activity and exact location are unknown. In consequence, there is a threat of the travel of nuclear debris, as well as workers’ hazard during these refuse dumps development.