The distribution of natural (at the level of global background) and technogenic radionuclides in groundwater of the industrial zone in Sosnovy Bor town, where several nuclear power facilities are operating, was analyzed. The main technogenic radionuclides recorded in groundwater samples are cesium ( 137 Cs), strontium ( 90 Sr), and tritium isotopes. The first two aquifers from the surface are subject to contamination: the Quaternary and the upper zone of the Lomonosov aquifer. Based on extensive material on the engineering and geological studies of the work area, a 3D geological model and hydrodynamic and geomigration models of the industrial zone were constructed. By means of modeling, the extent and nature of changes in hydrogeological conditions of area resulting from the construction and operational drainage of the new stage of the Leningrad Nuclear Power Plant (LNPP-2) were determined. The “historical” halo of radioactive contamination of groundwater forming (1970-1990) at the site adjacent to the NPP, where the storage facility of low- and medium-level radioactive waste is located, falls into the zone of influence. Interpretation of monitoring data allowed obtaining the migration parameters for predictive estimates. Modeling has shown that during the time of the LNPP-2 operation there was no intake of contaminated water by the drainage system of the new power plant.
The study presents experimental results illustrating a certain tendencies in the change in physical and mechanical properties of the Vendian clay formations over depth. A comparative analysis of samples from different borehole intervals has arrived at significant coefficients of correlation for the parameters that characterize the degree of the clay water saturation, compaction, and consistency with depth (the elevation of the core-bore sample in the profile). The rock deformation and strength parameters also demonstrate a dependence on the depth. The deformation modulus and the shear strength of the clay increase with increase in the depth of sampling.
A model assessment of the hydrogeological system water balance was carried out and the character of aquifers interrelation in the Sarov area was analyzed. The interaction of ground and surface waters was taken into account. During model calibration geofiltration parameters were specified and the distribution of area infiltration was found. The model structure took into account variations in the absolute elevations of the roof and base of the main aquifers.
A set of hydrogeological, hydrological and geophysical research methods was used to solve problems related to the estimation of groundwater resources. The results obtained were used in the development of numerical geofiltration models of groundwater deposits. Mathematical modeling is the main tool used in the assessment of groundwater resources and reserves within a number of allocated hydrogeological units. The conducted researches allowed to quantitatively estimate the degree of depletion of aquifer complexes and to give recommendations on replenishment of their reserves and rational water withdrawal regime.
The accuracy of interpretation of indicator sampling within the framework of typical calculation models is significantly affected by the combination of filtration heterogeneity of the reservoir and natural filtration flow, leading to a peculiar physical effect.
At present, in the special hydrogeological literature much attention is paid to the problem of studying the impact of technogenesis on the quality of groundwater. In the development of these studies, the article gives a consistent analysis of the conditions of formation of hydrogeochemical zonality in the groundwater flow within the halo distribution of technogenic solutions of potash production.
One of the main reasons for changes in the chemical composition of groundwater during drainage of developed deposits is the intensification of the overflow of pressure, more mineralized water of deep horizons, or squeezing (due to the growth of intra-class stresses) pore water from weakly permeable layers and blocks with a general decrease in head in the upper aquifers.
Чередование в разрезе слоев пород с различной проницаемостью свойственно в той или иной степени большинству водоносных горизонтов, приуроченных к терригенным породам; выдержанные по фильтрационным свойствам зоны могут быть в ряде случаев выделены и в некоторых разновидностях трещиноватых коллекторов ...
Под самоочищением подземных вод обычно понимают процессы, способствующие устойчивой консервации загрязняющих компонентов в водоносных горизонтах ...
The migration of a dynamically neutral impurity in porous (dispersed) media - externally homogeneous in capacitance and permeability - is most often considered on the basis of the microdispersion calculation scheme (also sometimes called the diffusion model); in the one-dimensional version, it corresponds to the following initial differential equation ...
Nowadays hydrogeophysical methods are more and more widely used in the practice of hydrological surveys. At the same time, there are often situations when the staging of geophysical work does not take into account the specifics of specific hydrogeological studies and is largely formal ....
