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Mining, Production and Development of Small Fractions of Gravel and Sand Aggregates in North-Western Poland

Kozioł Wiesław, Baic Ireneusz

Rocznik Ochrona Środowiska

2020

Tom 22, cz. 1

242--255

The gradual deterioration in the quality of raw material base of natural aggregates combined with the simultaneous increase in the demand of the construction industry for the best quality coarse fractions with grain sizes of 5-8 mm, 8-11 mm, etc., has a major impact on the growing volume of hard to sell and non-transferable (waste) fractions of aggregates produced in Poland. This applies especially to gravel and sand aggregates since in their resources the share of very fine fractions (below 2 mm) is systematically increasing, while the demand for such fractions in construction is limited and they are often treated as useless (waste) material. Problems with selling fine (waste) sands can be observed, among others, in the north-western region of the country. Since it is practically unknown what the volume of mining, production and consumption of these aggregates is, an attempt was made to assess the quantity of extracted and produced sand fractions of aggregates on a national and regional scale (provinces, regional zones). What constitutes a measurable indicator of the deterioration in the quality of resources is the tendency towards change in the average sand point (the percentage content of fine fraction of 0-2 mm) in the documented resources. For example in 2018, the average sand point in the balance resources was 67.8% and it increased by 5% over the period of 12 years (2007-2018). In the economic resources in Poland in 2018, the average SP was higher in comparison with the balance resources, namely 70.6%, and – what is characteristic – it increased by as much as 11.5% during the period of 12 years, i.e. the average annual growth of SP in industrial resources is ca. 1%. The highest growth was recorded in the southern region (by 16.4%); thus, the region with the best deposits in terms of quality (grain size) experiences the fastest deterioration. Estimated calculations show that in 2016, it was actually possible to obtain approximately 51.8 million Mg of gravel aggregates and 84.6 million Mg of sand assortments (0-2 mm); thus, the estimated total production of gravel and sand aggregates probably amounted to approx. 136.4 million Mg, i.e. about 78.7% of the annual production of gravel and sand according to PGI. The remaining part (21.3%) represents losses (useless fractions). The zone division of extraction and production of gravel and sands shows that the positive balance of sand production occurs mainly in the northern region (+19.4 million Mg), while the southern region (+3.2 million Mg) is in balance with the deficit in the central region (-3.0 million Mg). Relatively large positive balance of sand production is recorded in two provinces: Pomeranian (+5.3 million Mg) and West Pomeranian (+3.0 million Mg). The lack of periodic demand for such sands should be the basis for their classification as a by-product and their storage in separate storage sites. The analysis and calculations should contribute to the development of more accurate market forecasts of demand for and production of natural aggregates, especially of gravel and sand, both in Poland and in individual regions.

Stopniowe pogarszanie się jakości bazy surowcowej kruszyw naturalnych i równocześnie wzrost zapotrzebowania budownictwa na najlepsze jakościowo grube frakcje o uziarnieniu 5-8 mm, 8-11 mm, itd., ma duży wpływ na wzrost frakcji trudno zbywalnych i niezbywalnych (odpadowych) produkowanych w kraju kruszyw. Dotyczy to szczególnie kruszyw żwirowo – piaskowych w zasobach których systematycznie wzrasta udział frakcji drobnych (poniżej 2 mm), na które jest ograniczone zapotrzebowanie budownictwa i często traktowane są jako materiał nieużyteczny (odpadowy). Problemy ze zbyciem drobnych (odpadowych) piasków występują miedzy innymi w regionie północno-zachodnim kraju. Ponieważ praktycznie nie wiadomo jakie jest wydobycie, produkcja i zużycie tych kruszyw podjęto próbę oceny w skali kraju i poszczególnych regionów (województw, stref regionalnych) ilości wydobywanych i produkowanych frakcji piaskowych kruszyw. Wymiernym wskaźnikiem pogarszania się jakości zasobów kruszyw jest tendencja zmian średniego punktu piaskowego (procentowa zawartość frakcji drobnej 0-2 mm) w udokumentowanych zasobach. Przykładowo w 2018 r. w zasobach bilansowych średni punkt piaskowy wyniósł 67,8% i w ciągu 12 lat (2007-2018) wzrósł o 5%. W zasobach przemysłowych w kraju w 2018 r. średni PP był wyższy w porównaniu do zasobów bilansowych – 70,6% i co charakterystyczne w ciągu 12 lat wzrósł aż o 11,5%, czyli średnioroczny wzrost PP w zasobach przemysłowych wynosi ok. 1%. Najwyższy wzrost odnotowano w regionie południowym (o 16,4%), czyli w regionie mającym pod względem jakości (uziarnienia) najlepsze złoża, następuje najszybsze ich pogorszenie. Z przeprowadzonych szacunkowych obliczeń wynika, że w 2016 roku praktycznie możliwe było do uzyskania ok. 51,8 mln Mg kruszyw żwirowych i 84,6 mln Mg asortymentów piaskowych (0-2 mm), czyli szacowana łączna produkcja kruszyw żwirowo-piaskowych prawdopodobnie wyniosła ok. 136,4 mln Mg to jest ok.78,7% rocznego wydobycia wg PIG żwirów i piasków. Pozostałą część (21,3%) stanowiły straty (frakcje nie użyteczne). Z podziału strefowego wydobycia i produkcji żwirów i piasków wynika, że dodatnie saldo produkcji piasków ma głownie region północny (+19,4 mln Mg), zaś region południowy (+3,2 mln Mg) bilansuje się z deficytowym regionem środkowym (-3,0 mln Mg). Stosunkowo duże saldo dodatnie produkcji piasków mają województwa pomorskie (+5,3 mln Mg) i zachodniopomorskie (+3,0 mln Mg). Brak okresowego zapotrzebowania na tego typu piaski powinien być podstawą do ich uznania jako produkt uboczny i ich składowania na oddzielnych składowiskach. Analiza i obliczenia powinny się przyczynić do opracowania dokładniejszych prognoz rynkowych zapotrzebowania i produkcji w Polsce i w poszczególnych regionach kruszyw naturalnych w tym szczególnie kruszyw żwirowo-piaskowych.

Water chemical composition characteristic in the upper part of the Sztoła River

Juśko K., Kasprzak A., Pietrzak D.

Geology, Geophysics and Environment

2016

Vol. 42, no. 1

81--82

The Sztoła River crosses Lesser Poland and Silesia voivodships in the region of Olkusz zinc and lead ores mining and sands extraction. It is one of the left-bank tributary of Biała Przemsza. Its sources are located southwest of Olkusz. In the geological structure of Sztoła water catchment area, on the basis of conducted drillings, the following deposits can be distinguished: Paleozoic, represented by Permian deposits, Mezozoic-Triassic deposits, and Cenozoic-Quaternary deposits (Buła 2000, Motyka 2010). Hydrodynamic conditions in the region of Sztoła have been strongly interrupted by the development of zinc and lead ores mining and a sand pit, which required an application of drainage. The first system of drainage was adits built in 16 th century, which resulted in a decrease of the groundwater table level from few to over a dozen meters (Żukowski 1946, Górnisiewicz 1975, Molenda 1977, Kosiński 1882). The intensive development of mining in this region began in the first half of 19 th century, along with appearance of new drainage techniques. The Sztoła River changed its character from draining to infiltrating on its the whole length as the effect of development of vast zinc and lead ores mine depression cone, related to the exploitation of the „Pomorzany” mine, and later with a gravitational drainage of sandpit „Szczakowa” (Witczak & Motyka 1975, Haładus et al. 2007). In the upper part of the river it resulted with a partial dry out of the riverbed. Water flowing in the river originated from the drainage of Olkusz zinc and lead ores mines and is directed there through Baba channel. A research conducted in the summer of 2014 examined the upper part of the Sztoła River. Groundwater taken from springs, as well as surface water, was collected, and the areas of critical riverbed dry out were identified. A complete physicochemical analysis was carried out in the AGH hydrogeochemical laboratory in Cracow. On the basis of the received data, the characteristics of chemical composition of groundwater and surface water were prepared. Their hydrochemical type, pH values, electrolytical conductivity was determined. Chemical composition was also presented in the selected graphical forms (Piper, Collins, Pie Chart). Based on analysis, the statistical parameters of composition of water from the research region were calculated. Furthermore, the quality of underground and surface water was evaluated according to the existing standards, and suitability to consumption by people was determined. The Obtained data were also compared with archival results of samples collected within the investigated area.

Impact of sand extraction from the bottom of the southern Baltic Sea on the relief and sediments of the seabed

Uścinowicz S., Jegliński W., Miotk-Szpiganowicz G., Nowak J., Pączek U., Przezdziecki P., Szefler K., Poręba G.

Oceanologia

2014

No. 56 (4)

857--880

Investigations of the geological structure and seabed dynamics as well as the morphological and sedimentological effects of sand extraction generated by different mining techniques were carried out in Polish waters of the Baltic Sea, NW of the Gulf of Gdańsk, at a water depth of 15-17 m. Three research cruises took place: just before, directly after and 11 months after dredging operations. Seismoacoustic profiling, a multibeam echosounder, a side-scan sonar, a 3 m vibro-corer and a box-corer were used during the research cruises. The grain size distribution and 137Cs content of the sand samples were determined. Marine shells were dated by the AMS14C technique and pollen analyses were carried out on samples of muddy sands lying below the marine sand. A 2 to 4.5 m thick layer of marine sands lies on the boulder till and locally on late Pleistocene ice margin lake deposits. The 137Cs content indicates that the 0.4-0.8 m thick sand layer is mobile during storms. After the dredging operations, four pits with diameters from 80 to 120 m, depths from 3 to 4.5 m and slopes with gradients up to 30-55° were measured. Several smaller irregularly shaped pits and double furrows 30-150 m in length and 0.3-0.5 m in depth were found. The sonar mosaic also shows a 50-100 m buffer zone of fine sand around the pits which flowed over the dredger's side with water and settled on the bottom. During one year after the dredging operation the furrows generated by trailer suction hopper dredging as well as the fine sand cover around the pits disappeared completely. The four post-dredging pits left by stationary suction dredging were shallower by 2-2.5 m, their diameters increased by 40-50 m, the gradient of the slopes was reduced by up to 5-10°, and the total volume was only about 3.5% smaller than directly after dredging.