Bezpieczeństwo Pracy i Ochrona Środowiska w Górnictwie Number 10/2021

Along with the technical progress in the area of explosives use in civil operations, the regulations concerning to work safety also had to evolve. They regulate issues related to the transport, storage and use of explosives intended for civil use. Particularly responsible tasks related to this have been entrusted to the President of the State Mining Authority, whose main task is to approve the products for use in mining plants (also about blasting equipment) and keeping a register of explosives intended for civil use. The State Mining Authority is also a market surveillance authority for explosives used in mining. In the 2004-2020 over 1,000 explosives were registered. Equally important tasks were entrusted to the directors of district mining offices. They are related to the issuing of permits for the acquisition, storage or use of explosives. Despite technical progress and the expansion of regulations that clearly define the obligations related to the conduct of blasting, there are still accidents resulting from improperly performed blasting. The dispersion of rock fragments beyond the established safety zone should be considered among the most common undesirable effects of the use of explosives in opencast mines. The reason is the incompatibility of the amount of explosives to the mining and geological conditions, as well as the lack of control of the excavation before blasting works. This proves the lack of experience as well as the disregard of the dangers by the persons performing and supervising blasting works. Consequently, it leads to an increase in the exploitation costs of the deposits.

The article presents the influence of the climate in mining excavations on the value of human body impedance. The physiology of the thermoregulation system of humans in specific conditions of deep mine workings is discussed. The methods of assessing climatic conditions are presented. Based on the author's earlier studies, the relationship between changes in the impedance of the human body on the voltage and underground climate measured with a catatermometer was presented. As catatermometer measurements are difficult to perform, the climate was converted into ambient temperature and relative humidity in workings. The given equation (6) shows the dependence of changes in the impedance of the human body on temperature and humidity. Tables 1, 2 & 3 show the values of human body impedance for typical shock current flow paths: hand - hand, hand - legs and hand - torso.

Exemplified by scarp 20/III in field II in the “Szczakowa” Sand Mine and supported by a description of sand exploitation systems (longwall and open-pit), the article presents the effects of land reclamation. Works carried out as part of primary reclamation included, among others, formation of scarps, construction of maintenance rods, reservoirs, a network of drainage ditches and culverts. Detailed reclamation works included, among others, mineral fertilization and seeding of papilionaceous-leguminous plants, and final reclamation included: plantings of: black locust, pine (common and black), gray alder, box elder, birch and larch, as well as such bushes as: Siberian peashrub, Russian olive, common ninebark, bird cherry and black cherry, or rowan. Didactic paths were also routes to present the restoration of biological life on the reclaimed areas. Scarp reclamation assumed the establishment of forest habitats similar to a dry forest or a drier version of a fresh forest. Its current effects prove the efficiency of the methods applied, which aim at creating forest habitats surpassing, in some aspects (e.g. resistance to pollution), natural habitats, and contributing to increasing the ecological value of the landscape by introducing mixed forests and biocenoses with a larger number of plant and animal species.