The timely identification of areas where man-made radionuclides migrate through water streams is highly important for the territory of the former Semipalatinsk Test Site since the aquatic environment is currently a source of secondary contamination of environment. This article presents research findings on radioactively contaminated Lake Kishkensor located at the Semipalatinsk Test Site territory. As a result of this research, a new locally contaminated spot was discovered in the vicinity of the “Balapan” test site. Lake Kishkensor was found to be contaminated with man-made ³H and ⁹⁰Sr. The ³H activity concentration in surface waters reached 430 kBq/L, and the concentration of ⁹⁰Sr reached 100 Bq/L. In the sediments, the ³H activity concentration reached 700 kBq/kg, while that of ⁹⁰Sr and ^239+240Pu reached 310 Bq/kg and 250 Bq/kg, respectively. Ground water was found to be a source of surface water and sediment contamination. The monitoring results showed that the contamination level of the lake largely depended on the season and the inflow of contaminated ground water.

Snowpacks serve as an informative deposition medium for assessing the spatial distribution of atmospheric fallout and technogenic load in areas with persistent snow cover. This study examined the chemical element content in the solid fraction of the snow cover (SFSC) in Pavlodar Region. Fifty-five samples were collected, covering industrial, buffer, non-industrial, and background zones. The elemental composition of the SFSC was determined using inductively coupled plasma mass spectrometry (ICP-MS). The results revealed marked spatial heterogeneity in the distribution of chemical elements. The Pb levels detected exceeded background values by a factor of 2 to 100, indicating a significant aerotechnogenic impact on the study area. Elevated concentrations (of Pb, Sr, and V) and peak accumulation levels were recorded in the zones directly affected by industrial facilities and in the corresponding buffer zones subject to this influence. Principal component analysis (PCA) identified two main factors of elemental composition variability. The first principal component (PC1) was characterized by high positive loadings primarily associated with rare-earth elements (REEs). The observed spatial pattern reflects a combination of local industrial impact and the regional transport of chemical elements. This study represents a pilot phase of long-term monitoring aimed at assessing the spatial distribution of chemical elements in snow cover and identifying areas of elevated technogenic impact.

The article presents the results of developing a web application for sustainable management of land and water resources in the territory of the former Semipalatinsk Test Site (STS), located in areas planned for economic use. The study describes the process of creating a spatial database using PostGIS, implementing server-side logic in Django, and visualizing geospatial objects with Leaflet.js. The developed application provides tools for displaying, filtering, and editing radiation and environmental data, including soil and water sampling points, geological structures, and infrastructure elements. The paper outlines the stages of developing a REST API (Representational State Transfer Application Programming Interface), mechanisms for importing data in CSV (Comma-Separated Values) format, and tools for interactive layer management on the map. The system is designed to support decision-making in the field of radiation safety and environmental planning.

Radioactive and chemical contamination of aquatic systems remains a key environmental concern in areas affected by historical nuclear testing. The objective of this study was a comprehensive geochemical and ecotoxicological screening assessment of bottom sediments in the Shagan River, which partially flows through the Balapan test site within the Semipalatinsk test site. This 2 km stretch is potentially affected by groundwater discharge hydraulically connected to the Atomnoye Lake retaining zone. A total of 21 bottom sediment samples were collected over a 2 km stretch, and their elemental composition was determined using inductively coupled plasma mass spectrometry (ICP-MS). Bottom sediment quality was assessed using the geoaccumulation index (Igeo) and ecotoxicological criteria, including the threshold effect concentration (TEC), probable effect concentration (PEC), least impact level (LEL), and high impact level (SEL). The results revealed significant spatial heterogeneity in the element distribution and local geochemical anomalies. Manganese (Mn) and molybdenum (Mo) corresponded to the Igeo index category of severe contamination, while zinc (Zn) demonstrated an extremely high contamination level (Igeo = 6), exceeding the PEC threshold by 16 times. Mn concentrations also exceeded the SEL by 15 times. These results provide a baseline geochemical profile for a previously understudied and ecologically sensitive section of the Shagan River, identifying zones of local geochemical enrichment in bottom sediments and laying the foundation for further hydrogeochemical, mineralogical, granulometric, and ecotoxicological studies.

Atmospheric metal pollution in urban ecosystems is a critical global issue. Feral pigeons (Columba livia) serve as effective bioindicators of ambient air quality. This pilot study evaluates their applicability across three contrasting regions in Kazakhstan: Ust-Kamenogorsk (non-ferrous metallurgy), Pavlodar (coal-fired power generation), and Bigash village (rural background). Concentrations of 14 metal(loid)s and 10 rare earth elements (REEs) in feathers were determined via ICP-MS/ICP-OES and analyzed using principal component analysis, hierarchical cluster analysis, and pollution indices. In Ust-Kamenogorsk, high contamination factor (C_f) values for Cd (26.0), Pb (41.2), and As (19.0) indicated ‘very high contamination’ from non-ferrous metallurgy. In Pavlodar, C_f values for Cd (5.0), As (5.0), and Cu (7.3) showed ‘considerable contamination’ linked to coal combustion and oil refining. The total Metal Pollution Index for Ust-Kamenogorsk (11.1) was 4.8 times higher than for Pavlodar (2.3). REE profiles showed a ‘dilution effect’ driven by industrial dust, except for gadolinium, for which a pronounced concentration peak was recorded in Pavlodar. Multivariate statistics confirmed the effectiveness of using pigeon feathers as an integrative tool to differentiate zones of high technogenic pressure. Overall, this pilot study lays the foundation for long-term biomonitoring of the urban environment in industrial centers of Kazakhstan with heavy pollution loads.