Liquid Waste Storage Research Articles

Total Radiological Dose and Safety Assessment of Workers in Radioactive Liquid Waste Storage Location in Al Tuwaitha Site

This study aims to determine the total effective dose (external and internal) in the radioactive liquid Waste Hall (WH) in the Radiochemistry Laboratories building (RCL) in Al- Tuwaitha site in order to estimate the radiation risk for workers in this place. The external effective dose was calculated by an indirect method using ThermoLuminescent Dosimeters (LiF: Mg, Ti (TLD-100)) by placing them in the waste hall for one month. The internal effective dose was estimated by collecting eight air samples (environmental samples) from different locations in WH using an air sampler pump (Sniffer) to collect air samples loaded with particles or dust which are deposited on cellulose filter papers (φ 125mm). This was done for two flow rates the lowest and the highest values of the air sampler pump of 5CFM and 20CFM, respectively.The filter papers were chemically treated using the digestion method. The radionuclides in these samples were measured using a gamma spectrometry system equipped with a high-purity germanium detector (HPGe), and the radioactivity concentration was measured using a gross alpha beta gamma system. The results showed 137Cs of low concentration was deposited on the filter paper. The total annual effective dose rate (external and internal) results showed that the highest in WH was (6358.97μSv/year) for the low probability scenario and (1589.74 μSv/year) for the realistic scenario.

MATHEMATICAL MODELS OF THE NODE OF TECHNOGENIC INFLUENCE, TAKING INTO ACCOUNT THE MAIN DIRECTIONS OF MATERIAL FLOWS IN THE LOGISTICS OF MINING ENTERPRISES

ABSTRACT. The aim of the work is to create a mathematical model of liquid waste storage that accumulates processed products and mine waters simultaneously from many mining and processing plants, taking into account technological constraints on waste volumes and climatic factors depending on the season. The proposed mathematical model of node of technogenic influence is based on the balance of material flows in and out the node. A typical node of technogenic influence is an accumulation node. In the problem considered in this paper, the accumulation node is a waste storage facility where liquid man-made deposits are stored. The model of this node includes a system of equations describing the height of the water mirror and the bottom level depending on the volume of placers and water in and out for the analysed period of operation, taking into account the geometric features of the storage. The main directions of material flows can be formed from two or three nodes of technogenic influence. The first case is typical for underground mining, and the second one is typical for open pit mining. In the second case, the main direction is formed from the node of extraction of primary deposits, the node of processing or separation, and the node of accumulation or the node of storage of man-made deposits. The mathematical model makes it possible to determine the level of the free surface mirror in any month of the year, as well as to calculate the change in the current height of the water mirror in storage for any period of the year, such as spring months or all year round.

Effect of metallic redox ions on the corrosion behavior of GTAW weldment of type 304L stainless steel in simulated non-radioactive PUREX and HLLW medium

Nuclear-spent fuel reprocessing and high-level liquid waste (HLLW) storage containers possess various inorganic higher valance oxidizing metallic ions and fission products, further influencing nitric acid corrosion through the PUREX route. This study evaluated the effect of nitric acid corrosion on gas-tungsten arc weldment (GTAW) of stainless steel (SS) 304 L in simulated reprocessing and HLLW medium in non-radioactive conditions. The effect of oxidizing metallic cations, which were present as the major amount in the mark-I spent fuel of fast breeder test reactors (FBTR) in India; these are Cs+1, Nd+3, Mo+6, Fe+3, and V+5 as a surrogate redox system for Pu(VI)/Pu(IV) and Np(VI)/Np(V) system was evaluated by the electrochemical corrosion test method in 2 M, 6 M, and 8 M nitric acid solutions. The resistance of polarization (Rp) value decreases with the nitric acid concentration, and the effect of oxidizing ions in different nitric acid concentrations also changes. The three-phase corrosion (boiling liquid, vapor, and condensate phase) resistance behavior in different concentrations (6 M and 8 M) of the nitric acid medium, without and with redox ions, has been evaluated. The corrosion rate is higher in the liquid phase compared to the vapor and condensate phases. On the other hand, it is relatively higher for the inorganic metallic redox ions containing solutions.

Nitrate-induced cancrinite precipitation in alkaline solution at low temperature and relevance to the Bayer alumina process

Cancrinite-type zeolites were proposed as functional materials which exhibits promising photocatalytic properties, enables carbon capture and can even be used in the storage of liquid radioactive waste. Conventional cancrinite is precipitated by reacting Na2CO3 or CaCO3 with Al- and Si- rich alkaline solutions at an elevated temperature of 150 °C in Bayer Alumina process. Here we report the effect of nitrate on cancrinite formation at 90 °C. At low alkalinity, nitrate accelerates transformation of zeolite LTA to sodalite, followed by minor cancrinite precipitation at a later stage. In highly alkaline solution, nitrate addition shortens the induction time required for homogenous cancrinite precipitation. In highly alkaline solutions with nitrate, it was also found that zeolite LTN precipitates as an intermediate phase which transforms into sodalite/cancrinite. Raman spectroscopy and thermogravimetric analysis confirmed the incorporation of nitrate into the structure of cancrinite and its thermal stability, at room temperature. These findings may help to optimize the Bayer process, mitigate the potential environmental risks of bauxite residue, and aid in the capture of the greenhouse gases from the air.

Retrieval and processing of radioactive muck settled in the bottom of radioactive liquid waste storage tanks

Alkaline radioactive liquid waste storage tanks contain huge quantity of chemical muck settled at the bottom of the tank. This muck contains fission products, corrosion products, actinides and other chemicals. As the precipitate remain settled for decades, the elements get converted from hydroxides to oxy-hydroxides and oxides which are difficult to dissolve in mineral acids. Treatment feasibility of this legacy muck was studied by simulating muck using acidic radioactive liquid waste followed by its dissolution and conditioning in borosilicate glass matrix. Dissolution was better in a mixture of nitric acid and oxalic acid medium. Immobilization studies of the muck dissolved solution in borosilicate glass showed that 25% waste oxide could be immobilized in glass matrix whereas when mixed with High Level liquid Waste (HLW), 34% waste oxide could be immobilized in glass matrix. Chemical durability and thermal stability of the glass samples were evaluated and are within the appropriate limit.

Мониторинг почвенной альгоцианофлоры на техногенной территории

The results of monitoring higher vegetation and soil algocyanoflora on the territory of the self-overgrowing liquid waste storage facility after reclamation are presented. The species composition of higher plants and algocyanoflora on monitoring sites depends on the whole complex of soil formation factors: the initial heterogeneity of the substrate, topography, and moisture conditions. Reduced relief and excessive moisture contribute to development of moisture-loving species of higher plants, algae and cyanobacteria; the density of grass sod exacerbates the competitive relations of higher plants (monodominance) and contributes to decrease in the species diversity of microphototrophs. For the entire observation period from 2019 to 2022 66 species were identified on the territory of the backfilled tailing dump including: Cyanobacteria – 29; Chlorophyta – 20; Xanthophyta – 5; Eustigmatophyta – 3; Bacillariophyta – 9. Cyanobacteria (CB) dominate the algocyanoflora communities at all sites accounting for 43–47% of the species diversity. Few species of yellow-green and eustigmatophyte algae sensitive to technogenic pollution have been noted. The research did not reveal any regular relationship between soil pollution, vegetation species diversity and algocyanoflora composition. However, it can be assumed that the increased content of nitrates in soils in the low area under reed thickets may be the reason for the low species diversity of CB. Over time, increasing similarity of algocyanoflora on the monitoring sites was noted. The maximum difference in the species composition of algae and CB identified on the site under the monoassociation of common reed is conditioned by excessive soil moisture in the lowering of the relief.

Influence of Radioactive Sludge Content on Vitrification of High-Level Liquid Waste

The radioactive sludges formed at the bottom of high-level liquid waste (HLW) storage tanks pose challenges when the HLWs are vitrified. This study aims to determine the influence of the sludge content (enriched in Na2O, Al2O3, NiO, Fe2O3, and BaSO4) on the structure and properties of waste glasses in order to find the optimal ratio of sludges to HLW during vitrification. In the experiments, the simulated sludge and simulated HLW were mixed at different ratios from 0:8 to 4:4, with an overall waste content of 16 wt %, in a borosilicate glass wasteform. It is found that the glass density, molar volume, sulfur retention, and glass transition temperature changed little when increasing the sludge content of the glasses, while the viscosity, chemical durability, and crystallization features of the glasses varied notably. The crystals formed in the glasses during the thermal treatment were exclusively Fe-substituted diopside (Ca, Mg, Fe)2Si2O6. An increase in the Al2O3 and NiO content of the glasses may have been responsible for the increased crystallinity at high temperatures. The leaching rate of Si, B, Na, and Cs from the glasses declined with the increasing addition of sludge to the glasses. Although all the glasses fulfilled the requirements for vitrification processing and glass-product performance, it is recommended that the sludge content of the whole waste should not exceed 25 wt %. This study guides further research on the immobilization of high-level sludges.

Substantiation of environmentally safe modes and parameters of operation of mineral processing waste storage facilities

The subject of the paper is the modes and parameters of operation of mineral processing waste storage facilities. Liquid waste storage facilities that accumulate processing products and mine water from several mining enterprises are considered, taking into account climatic factors of influence, technological limitations on the volume of waste. The analysis of the main results shows that environmental safety in the operation of waste storage facilities is based on two principles: to prevent waste overflow over the edges of the embankment dam and to provide a protective layer of liquid over the bottom, which is formed from particles of dusty and clay fractions. The purpose of the study is to scientifically substantiate the possible modes of operation of liquid waste storage of mineral raw materials processing and mining, as well as the creation of methods for calculating their maximum possible volumes entering the storage during the year, taking into account environmental safety. The study used the methodology of logistic systems, in the framework of which storage facilities are considered as a node of accumulation, and its model includes a system of equations describing the height of the water mirror and the bottom level depending on the volume of placers from the water volumes that entered and withdrawn from it during the period of operation, which is analyzed, taking into account the geometric features of the storage bowl. As a result, a mathematical model of liquid waste storage, which accumulates processing products and mine water from several mining enterprises, has been developed, taking into account climatic factors of influence, technological limitations on waste volumes. This model allows to determine the level of the free surface mirror in any month of the year, as well as to calculate changes in the current height of the free surface mirror in the storage for any period of time. On the basis of these formulas and ecological safety requirements at operation of artificial storages of wastes from processing of mineral raw materials the restrictions on volumes of wastes which enter the storage during a year, or during spring months have been received. The use of these restrictions allowed to determine and justify the rational values of capacities on salable concentrates of mining enterprises, duration of their downtime for a certain period of the year. Keywords: storage of mineral processing waste, height of the water mirror, environmental safety of operation.

Safety analysis of hydrogen explosion accident in high level waste tank

A large amount of radioactive waste liquid is generated in the spent fuel reprocessing process, and high-level waste is stored in a high-level waste tank. During storage, a hydrogen explosion accident may occur, resulting in the leakage of radioactive materials. This article reviewed the basic situation of high-level waste liquid and high-level waste storage system. The safety analysis of the hydrogen explosion accident was conducted, from the source and generation mechanism of hydrogen, the accumulation process of hydrogen in the tank, the possible ignition source and the possibility of explosion in the tank, the pressure generated by the hydrogen explosion, and the probability of tank failure due to hydrogen explosion are discussed. Suggestions were made on the design, operation, and safety analysis of high-level waste tanks in China, which provided a reference for the safe development of high-level waste storage facilities in commercial reprocessing plants.

Water quality adjacent to swine slurry holding ponds associated with a concentrated animal feeding operation

AbstractEnvironmental concerns exist over extended storage of liquid animal waste in outdoor holding ponds before land application, particularly in regions with underlying karst geology. To determine the effects of holding ponds on water quality, belowground interceptor trenches, groundwater (well), and a downslope ephemeral stream were monitored for water quality parameters. Nitrate‐nitrogen concentrations increased (p < .0001) in well and ephemeral stream samples but decreased in trench samples (Trench 1 with a p < .0001) near the swine production facility and holding ponds over a 5‐yr monitoring period (April 2014–June 2019). In contrast, chloride, which is a conservative element that can move freely through the soil without chemical, physical, or biological modification, and electrical conductivity decreased (p < .0001 to .0203) over the monitoring period in well and Trench 1 samples. Flow in the interceptor trenches was highly responsive to rainfall, suggesting the trenches were mainly capturing shallow subsurface flows initiated by rainfall. A lack of any increasing trend in chloride and electrical conductivity for ephemeral stream, well, or trench samples suggests that elevated nitrate‐nitrogen concentrations in well and ephemeral stream samples may have been influenced by sources other than the liquid manure holding ponds (i.e., sources that have low chloride and electrical conductivity values). In regions with underlying karst geology, surface and subsurface water resources may require more expansive monitoring to demonstrate liquid manure holding ponds effects on nearby water quality.

Tectonics of the Wysoka Kamieńska Graben (NW Poland) and implications for fault sealing potential

Reservoir confinement by faults is important for safe storage of liquid waste or hydrocarbons. Having access to 3D seismic and borehole data, we have interpreted the tectonic setting of the Wysoka Kamieńska Graben (WKG) in the NW part of the Polish Basin and subsequently made an interpretation of the sealing potential of the graben-bounding faults. The formation and development of the graben in the Late Triassic and Early Jurassic was controlled by mechanical decoupling in the salts of the Zechstein Group. The primary tectonic factor triggering the graben origin was dextral strike-slip movement along the regional fault zone in the Paleozoic basement, transtensional accommodation of which in the Zechstein-Mesozoic cover led to development of a horse-tail pattern of grabens. During the Late Cretaceous, the graben underwent minor tectonic inversion. Sealing potential analysis of the graben-bounding faults was performed for the Triassic–Jurassic sequence including juxtaposition seal and fault gouge seal components. Finally, we have focussed our interpretation on the Jurassic sequence where the best reservoirs have been recognized. Our results indicate good to moderate sealing potential of the Hettangian reservoir, poor to moderate sealing of the Pliensbachian reservoir and lack of sealing of the Bajocian reservoir. Hence, the Hettangian reservoir, characterized by large thickness, low clay content and a large regional extent, acts as a potential storage formation, being confined by the graben-bounding faults of the WKG

Mathematical modeling of the spread of pollutants in the atmosphere from the storage of liquid waste of pig complexes during reagent treatment

The effect of treatment of liquid organic waste from pig farms with various calcium-containing reagents, followed by neutralization to pH 7.0-8.5, on reducing the emissions of pollutants such as ammonia, hydrogen sulfide, methyl mercaptan, nitrogen and carbon oxides at various stages of treatment was studied. The article deals with mathematical modeling of changes in the concentration fields of pollutants over time. Dynamic processes of gaseous pollutants propagation in the surface air layer above liquid organic waste accumulators are simulated. The developed model will allow calculating the distribution of pollutants over the storage of liquid organic waste in a given period of time and calculate the concentrations of gaseous pollutants in steady-state and non-stationary modes during reagent treatment. The time of reducing the concentrations of pollutants to the required values is determined based on the results of a computational experiment in the VITECON software package. The corrected sizes of sanitary protection zones of the pig complex before and after reagent treatment are presented.

Microstructural evolution of granitic stones exposed to different thermal regimes analysed by infrared thermography.

Detailed knowledge of the behaviour of rocks under thermal stress is essential in a variety of fields such as the exploitation of oil and mineral resources, the geothermal sector, the storage of radioactive liquid waste, or even CO 2 capture and storage. Granites are widely studied and exploited in these fields, and they show different reactions to high-temperature and thermal cycles due mainly to their high mineralogical and textural heterogeneity. One of the features that influences the most the thermal response is the porosity. The objective of this study is to evaluate the influence of porosity when these rocks are exposed to different thermal treatments. For that purpose, experiments were carried out on four granitoids selected by their similar crystal size, but with variable mineral proportion and porosity values, ranging from 1 to 6%. Two kinds of tests were performed: i) progressive heating cycles from 90 °C to 130 °C to determine the critical threshold for thermal damage; ii) thermal fatigue with cycles of heating-cooling up to 200 °C. The porosity and the water transport phenomena of the samples were characterised before and after each cycle by the monitoring of capillary water uptake coupled with infrared thermography. This technique allowed to follow the capillary fringe migration during the test and the evolution of the cooling rate index. The direct assessment of the damage was carried out by mercury injection porosimetry, optical polarising microscopy, and scanning electron microscopy. The combination of all the results permitted to establish a link between the evolution of temperature and the modification of porous networks in granitoids. Microcracks appeared distinctly at a temperature between 90 °C to 130 °C for high porosity granitoids whose Quartz/Feldspar ratio was close to 1. For higher temperatures, the low porosity granitoids develop microcracks from the first heating cycle. The porosity then showed a stronger impact on thermal behaviour than the effect of the mineralogy. The results obtained from infrared thermography allowed to detect the strong variations in the microstructure. • The initial heterogeneity of a granite generates a different cracking threshold for the same type of granite. • Repeated heating leads to increasing damage to rocks • The initial porosity and the quartz/feldspar ratio play a role in the thermal behaviour of granite. • Infrared thermography is a promising tool to detect microcracking.

Риск заболеваемости солидными злокачественными новообразованиями у облученного на территории Восточно‑Уральского радиоактивного следа населения за 1957–2014 гг.

Purpose: Assessment of solid cancer incidence risk in the cohort of exposed population on the territory of the East Urals radioactive trace over the period of follow-up from 1957 to 2014 with the use of the individual doses provided by the latest TRDS dosimetry system.
 Material and methods: The explosion of the liquid radioactive waste storage tank at the «Mayak» Production Association on 29 September 1957 led to the pollution of the territories of the Chelyabinsk and Sverdlovsk Regions and the formation of the EURT, and the population residing on its territory was subjected to protracted chronic external and internal exposure. The analyzed cohort includes 21,384 people, 2,055 of whom received additional radiation before the 1957 accident due to residing in one of the Techa River settlements. The mean dose to the stomach for the members of the EURT cohort was 36 mGy, the maximum — 1.13 Gy. The analysis was performed using the DATAB and AMFIT programs (statistical software package EPICURE). A simple parametric model of excess relative risk (ERR) was used. Statistical significance and confidence intervals were obtained using the maximum likelihood method.
 Results: As a result of the analysis of the solid cancer incidence risk in the EURT cohort during the 57-year follow-up period using the linear model and the 5-year latent period, a statistically significant ERR was obtained which equals to 0.052 / 100 mGy (95 % CI 0.01–0.10, p = 0.02) in the entire EURT cohort. When the group of people additionally exposed on the Techa River before the 1957 accident was excluded from the cohort, the risk became insignificant. No significant modification of the dose dependence by non-radiation factors was revealed. The obtained results are compared well with the previous studies of the exposed population in the Southern Urals which were conducted in the Urals Research Center for Radiation Medicine, as well as in the world, devoted to the study of the effects of radiation exposure on population.

An External Dose Assessment of Worker during RadWaste Treatment Facility Decommissioning

Background: Kori unit #1 is permanently shut down after a 40-year lifetime. The Nuclear Safety and Security Commission recommends establishing initial decommissioning plans for all nuclear and radwaste treatment facilities. Therefore, the Korea Atomic Energy Research Institute (KAERI) must establish an initial and final decommissioning plan for radwaste-treatment facilities. Radiation safety assessment, which constitutes one chapter of the decommissioning plan, is important for establishing a decommissioning schedule, a strategy, and cost. It is also a critical issue for the government and public to understand. Materials and Methods: This study provides a method for assessing external radiation dose to workers during decommissioning. An external dose is calculated following each exposure scenario, decommissioning strategy, and working schedule. In this study, exposure dose is evaluated using the deterministic method. Physical characterization of the facility is obtained by both direct measurement and analysis of the drawings, and radiological characterization is analyzed using the annual report of KAERI, which measures the ambient dose every month. Results and Discussion: External doses are calculated at each stage of a decommissioning strategy and found to increase with each successive stage. The maximum external dose was evaluated to be 397.06 man-mSv when working in liquid-waste storage. To satisfy the regulations, working period and manpower must be managed. In this study, average and cumulative exposure doses were calculated for three cases, and the average exposure dose was found to be about 17 mSv/yr in all the cases. Conclusion: For the three cases presented, the average exposure dose is well below the annual maximum effective dose restriction imposed by the international and domestic regulations. Working period and manpower greatly affect the cost and entire decommissioning plan; hence, the chosen option must take account of these factors with due consideration of worker safety.

UC1 sampling plan, liquid waste storage tanks, JRC Ispra

The objective of INSIDER work package 3 (WP 3) is to draft a sampling guide for initial nuclear site characterization in constrained environments, based on a statistical approach. In this paper, deliverable 3.4 (D 3.4) is presented for WP 3, where the strategy developed in deliverables 3.1 (D 3.1) to 3.3 (D 3.3) is applied to the first of three reference use cases representative of existing decommissioning scenarios. The present discussion focuses on use case 1 (UC1): the liquid waste storage facility at the JRC site of Ispra (Italy). The proposed characterization strategy developed in D 3.2 is applied in a step by step approach to analyse the pre-existing information (obtained through the use of a pre-sampling questionnaire), and to utilise the available inputs towards the development of a sampling plan sufficient for allowing radiological characterization. The proposed sampling plan follows a three-step approach, i.e. determination of possible elevation in activity concentration by non-destructive testing, biased sampling of layers identified, and finally unbiased sampling after mixing of tank contents.

Растворение алюмосиликатных осадков в хранилищах жидких РАО

The article deals with the extraction of insoluble sediments formed in storage tanks during long-term storage of liquid radioactive waste from spent nuclear fuel reprocessing. Results of a thermodynamic analysis are presented enabling to assess the structure of the precipitation formed and to select most effective modes for thermal and hydrodynamic effects (cavitation technology) produced by liquid medium on eroded sediments. The paper presents the results of studies on the extraction of poorly soluble pulp components from storage tanks using cavitation technology.

ПРОЕКТУВАННЯ ГРЕБЕЛЬ ЗА КОМПЛЕКСАМИ НОРМАТИВНИХ АКТІВ ТА СТАНДАРТІВ З УРАХУВАННЯМ СЕЙСМІЧНИХ ВПЛИВІВ

В статті розглянуто основні комплекси нормативних актів та стандартів щодо проектування гребель і напірних дамб з ґрунтових матеріалів. Основним документом комплексу нормативних актів щодопроектування гідротехнічних споруд різних типів на сьогоднішнійдень є ДБН В.2.4-3:2010 «Гідротехнічні споруди. Основні положення». Існує система нормативних документів, що включає ДБН В.2.4-20:2014 «Греблі з ґрунтових матеріалів. Основні положення». У цих державних будівельних нормах визначено принципи (загальні положення) і вимоги до проектування, будівництва, експлуатації йреконструкції гребель і напірних дамб з ґрунтових матеріалів приновому будівництві, реконструкції та капітальному ремонті гідротехнічних споруд для об’єктів водного господарства, гідроенергетики, захисту територій від підтоплення і затоплення, складування рідких відходів промислових підприємств тощо, споруд усіх видів і класів наслідків (відповідальності), в тому числі з урахуванням сейсмічних впливів.Використання комплексу щодо гребель і напірних дамб з ґрунтовихматеріалів державних будівельних норм дозволяє здійснювати їхпроектування, будівництво, експлуатацію і реконструкцію в складних інженерно-геологічних умовах з врахуванням сейсмічнихвпливів, спостереження за спорудами та охорону довкілля.

ENVIRONMENTAL ASPECTS OF LARGE-TONNAGE PRODUCTION LIQUID WASTE STORAGE INTO THE UNDERGROUND STORAGE

The article presents the schemes of two fundamentally different ways of storing liquid waste. The technologies of large-tonnage production liquid waste storage are analyzed. The advantages and disadvantages of storage methods for liquid waste are identified. The limited suitable reservoirs number during deep storage in mandatory requirements terms for the absence of fresh water and isolation from them, the presence of regional waterproof tires (screens), which are low-permeable or permafrost, the presence of the necessary reservoir and the mining allotment boundaries, because when filling the reservoir, it is necessary to observe the restriction of the underground pollution distribution halo within the mining allotment boundaries. The actual sizes of underground pollution halos in reservoirs depend on the injected liquid waste volume and on the their distribution time. Liquid waste migration continues after the end of their injection into the well. It is possible that the halo of the liquid waste storage after conservation and liquidation of the injection well will exceed the boundaries of mining with drawal of the subsoil, and hazardous components of liquid waste will fall into aquifers of the upper hydrodynamic zone suitable for economic use. In order to eliminate the liquid waste possible migration beyond the boundaries of the subsoil mining allotment during the liquidation of an injection well, it is necessary to take measures to localize the contaminated area. Based on the analysis of the liquid waste storage applied methods, it has been established that deep storage in reservoirs is the most promising both in terms of ecosystem safety and the possibility of storing liquid waste of all hazard classes. Special attention after the conservation and liquidation of the injection well should be paid to the storage halo limitation. To exclude the liquid waste components migration into suitable for economic use aquifers of the upper hydrodynamic zone, a strategy is proposed for localizing the contaminated area by creating insulating screens.

ENVIRONMENTALLY SAFE TECHNOLOGY FOR STORAGE OF LIQUID WASTES OF MULTI-TONNEL PRODUCTION

The article describes the method and features of the insulation screens creation in order to exclude the possible migration of liquid waste hazardous components into the upper aquifers suitable for economic use, as well as the creation of separate storage areas of liquid waste different chemical composition. We proposed the creating insulating screens scheme for deep liquid waste storage. We determined the design feature of the special wells location. We considered two buffer liquids - 3 % aqueous solution of NaOSiO2, 0.05 % polyacrylamide solution in 50 % aqueous solution of CaCl, which form a hardening, insoluble, high-viscosity substance (insulating screen) upon contact. The optimal method of special wells drilling and fastening is determined. The choice of polyvinyl chloride pipes at the stage of casing construction is defined. We selected the necessary plugging solution and the method of qualitative formation of the casing string of a special well, equipment for hydraulic fracturing and injection of an insulating solution. We calculated the buffer fluid required volume and the insulating solution propagation radius for the real condition.