Radioactive contamination of the aboveground phytomass of marsh Labrador tea (Ledum palustre L.) in different periods after the Chernobyl accident was studied. Marsh Labrador tea is widely used in official and folk medicine. The studied species grows in over-moistened pine (less mixed) forests and open oligotrophic and mesotrophic marshes. It was found that in the first four years since the beginning of observations (1991), the magnitude of the specific activity of 137 Cs in above-ground vegetative phytomass of marsh Labrador tea, depending on a permanent sample area (PSA), decreased by 1.2-1.4 times. After 10 years, it decreased by 1.6-1.7 times, after 16 years by 1.9-2.1 times, after 21 years by 2.7-3.1 times, and after 27 years by 3.1-6.5 times. An increase in the magnitude of transitions factors was also observed on all PSA over time. Thus, the minimal increase within 1991-2018 was recorded in PSA 11-by 1.2 times and on PSA 13-by 1.4 times. The maximum decrease in the magnitude of transition coefficient was observed in PSA 16-by 2.7 times, in PSA 15-by 3.0 times, and in PSA 18-by 2.0 times. It was found that marsh Labrador tea belongs to the group of plants that are characterized by the high content of 137 Cs in the above-ground vegetative phytomass. Within the observation period (1991-2018), this content significantly exceeds the admissible levels of radionuclide content in plant medicinal raw materials that are used for manufacturing medical preparations. In the PSA with maximum magnitudes of soil contamination density (400.5±50.73 kBk•m-2) this excess made up 158.4 times in 1991, and 33.7 times (166.9±23.56 kBk•m-2) in 2018. For 27 years of observations, there has been a decrease in the density of radioactive soil contamination by 2.1-2.7 times, which is due to radionuclide decomposition, its vertical migration in the soil, and towards the components of forest ecosystems

Установлено, що продовжується інтенсивне надходження 137 Cs до надземної частини фітомаси та ягід чорниці. Дослідження проведено на дерново-середньопідзолистих, піщаних ґрунтах вологих суборів. Коефіцієнти переходу 137 Cs (м 2 кг -1 10 -3 ) в надземну частину чорниці (17 -53) значно більші, ніж в ягоди (4 -8). Виявлено зниження рівнів радіоактивного забруднення 137 Cs надземної фітомаси та ягід чорниці за період спостережень. Протягом 1991 -2016 рр. питома активність 137 Cs в ягодах чорниці знизилася у 3,7 -8,3 раза, у надземній частині -у 8,2 -19,2 раза. У верхньому 0 -10-см шарі мінеральної частини ґрунту вологих суборів міститься 69,9 % від сумарної активності радіонукліда в ґрунті. Найбільша величина цього показника встановлена для 0 -2-см шару мінеральної частини ґрунту -28,4 ± 2,0 %. Найбільша питома активність 137 Cs встановлена для розкладеної частини лісової підстилки та верхнього 0 -2-см шару гумусово-елювіального горизонту.

Forest ecosystems are complex areas in terms of rehabilitation of radioactively contaminated areas, so conducting an up-todate examination of these areas for radioactive contamination is relevant. The paper considers the improvement of methods of soil sampling for obtaining representative materials in the estimation of vertical migration of 137 Cs in the soil profile and the level of soil contamination with 137 Cs. The density of radioactive soil contamination was studied by reducing the number of selected samples from 30 to 3 in the layers of 10, 20, and 30 cm. The results show that when the number of soil samples decreases, the average magnitudes of soil contamination with 137 Cs are not significantly different within each analyzed layer. It was noted that at sampling in the 10-centimeter layer, the studied indicator was 1.3-1.4 times lower than in the layers of 20 and 30 cm, and there is no difference between the latter. To obtain reliable levels of radioactive contamination of the territory, it is necessary to perform 10-time repeated sampling in the forest soil layer of 30 cm. At a decrease in the number of soil samples from 10 to 3, the fluctuation of average values of the specific activity of 137 Cs in different layers of soil profile is low. To obtain representative magnitudes of 137 Cs content in each layer of the soil profile, it is necessary to make various samplings. Thus, for 4-time repeated sampling, is sufficient for all layers of forest litter, and 6-time repeated sampling is enough for the humus-eluvial horizon. It is necessary to perform 8-time repeated sampling for the eluvial and illuvial horizon, and 10-time repeated sampling for illuvial sand and parent rock. The obtained results make it possible to carry out up-to-date examination of forests for radioactive contamination based on the updated methodology and using the obtained data on 137 Cs migration in forest soils

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Prospects for using broken stone quarries waste The analysis of the production of broken stone materials shows that the processing enterprises of this product have problems with the storage of waste product. The dumps of waste cover huge areas of land suitable for agriculture use. The accumulation of waste also affects the environment. Its accumulation occurs due to the imperfect technology of waste products recycling. Granite screenings is the waste of this production. The introduction of modern waste recycling technologies allows to get washed sand, which becomes a competitive product. The paper analyzes the granulometric composition of different types of sand, compares granulometric composition of different types of sand and the directions of use of sand in various industries, also it highlights construction and road works. In general, the paper is dedicated to the production of granite sand. The physical and mechanical properties of granite sand and its fractional composition are described. A comparison of the granulometric composition of granite sand with an «ideal» granulometric curve of filler with a grain size of 2.5 mm (by Fuller) is made. The analysis shows that the curve for washed sand closely approximates to the «ideal» curve. This fact indicates that granite sand has a wide range of applications as filler for production plaster and building mortars. According to quality indicators, washed sand meets European quality standards. The widespread use of granite screenings makes it possible to reduce the environmental impact and improve the technical and economic performance of enterprises that are engaged in mining of broken stone.