20.500.12556/DiRROS-17635 Impact assessment of the Gajke and Brstje landfills on groundwater status using stable and radioactive isotopes Ocena vpliva odlagališč Gajke in Brstje na stanje podzemne vode z uporabo stabilnih in radioaktivnih izotopov Waste disposal in landfills represents a severe threat to aquatic environments on the local, regional, and global levels. In Slovenia, there are 69 registered landfills where groundwater is regularly monitored. However, isotope techniques are not regularly employed. Therefore, we employed isotope analysis of hydrogen, carbon, and oxygen in combination with total alkalinity to assess the impact of the selected landfill on groundwater and to evaluate the biogeochemical processes at work. The δ18O, δ2H, δ13CDIC, 3H activity and total alkalinity were determined in October 2020 at 12 sampling points from the surrounding area of the Gajke and Brstje landfills and leachate from the Gajke landfill. The δ18O (-9.24 ± 0.3 ‰) and δ2H (-64.9 ± 2.7 ‰) in groundwater indicate that the main water source consists in direct infiltration of precipitation, with no significant isotopic fractionation. Total alkalinity in the investigated area ranges from 5.45 to 73 mM and δ13CDIC from –14.9 to +6.1 ‰, respectively. Higher values of total alkalinity (up to 73 mM), δ13CDIC (up to +6.1 ‰), δ18O (-7.64 ‰) and 3H (209.8 TU) are detected in the leachate, indicating biogeochemical process related to CO2 reduction or methanogenesis. Methanogenesis could be present at locations GAP-10/13 (Brstje landfill) and G-2 (Gajke landfill) with δ13CDIC values ranging from –8.2 to –7.6 ‰ and with dissolved oxygen values around 0 % and elevated 3H values (from 16 to 18 TU). This study demonstrates the effectiveness of isotopic analysis as a valuable tool for monitoring landfills, revealing shifts in biogeochemical processes within the groundwater there. Odlaganje odpadkov na odlagališčih predstavlja resno grožnjo za vodna okolja na lokalni, regionalni in globalni ravni. V Sloveniji je 69 registriranih odlagališč, kjer se redno izvajajo obratovalni monitoringi kemijskega stanja podzemne vode. Kljub temu izotopske tehnike niso rutinsko uporabljene. Zato smo uporabili analizo izotopov vodika, ogljika in kisika v kombinaciji s skupno alkalnostjo, da bi ocenili vpliv izbranega odlagališča na podzemno vodo in ovrednotili biogeokemične procese. δ18O, δ2H, δ13CDIC, aktivnost 3H in skupna alkalnost so bile določene v oktobru 2020 v 12 vodnjakih v okolici odlagališč Gajke in Brstje in v izcedni vodi iz odlagališča Gajke. Vrednosti δ18O (-9,24 ± 0,3 ‰) in δ2H (-64,9 ± 2,7 ‰) v podzemni vodi kažejo, da je glavni vir vode neposredna infiltracija padavin, brez bistvene izotopske frakcionacije. Totalna alkalnost na preiskanem območju se spreminja od 5.45 do 73 mM, δ13CDIC od –14.9 do +6.1 ‰. Višje vrednosti totalne alkalnosti (do 73 mM), δ 13CDIC (do +6.1 ‰), δ18O (-7.64 ‰) in 3H z 209.8 TU so zaznane v izcedni vodi CERO Gajke (kanal), kar kaže na biogeokemijski proces redukcije CO2 ali metanogeneze. Metanogeneza bi lahko bila prisotna tudi na lokacijah GAP-10/13 (odlagališče Brstje) in G-2 (odlagališče Gajke) z δ13CDIC vrednostima od -8.2 do -7.6 ‰ in z vrednostjo raztopljenega kisika okrog 0 % ter povišano vrednostjo 3H (od 16 do 18.2 TU). V tej raziskavi smo dokazali, da so izotopi koristna orodja v monitoring raziskavah odlagališč in kažejo na spremembe biogeokemičnih procesov v podzemni vodi. groundwater monitoring landfill stable isotopes tritium Gajke Brstje podzemna voda monitoring odlagališče odpadkov stabilni izotopi tritij Gajke Brstje true false true Angleški jezik Slovenski jezik Neznano 2024-01-05 03:36:58 2024-01-16 10:28:46 2024-01-17 03:40:21 0000-00-00 00:00:00 2023 0 0 str. 275-283 no. 2 vol. 66 2023 0000-00-00 Zaloznikova Objavljeno NiDoloceno 0000-00-00 0000-00-00 2023-12-21 556.3 0016-7789 10.5474/geologija.2023.014 179274499 1867-Article_Text-12342497-1-10-20231221-1.pdf 1867-Article_Text-12342497-1-10-20231221-1.pdf 1 B00EC37CC730A96B3C839817B0FA732B 0e6f7d6691a4e61f4c4c125d373abe00456acb050f729b0ebe49bc1129078d0f d62460b4-b451-11ee-b0d4-001a4af901a5 https://dirros.openscience.si/Dokument.php?lang=slv&id=24196 Geološki zavod Slovenije Institut Jožef Stefan Geologija 0 0 0