{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,18]],"date-time":"2026-08-18T04:30:22Z","timestamp":1787027422863,"version":"build-2736575974"},"reference-count":36,"publisher":"MDPI AG","issue":"16","license":[{"start":{"date-parts":[[2026,8,14]],"date-time":"2026-08-14T00:00:00Z","timestamp":1786665600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Silesian University of Technology","award":["06\/060\/BK_25\/0133"],"award-info":[{"award-number":["06\/060\/BK_25\/0133"]}]},{"award":["06\/060\/BK_25\/0133"],"award-info":[{"award-number":["06\/060\/BK_25\/0133"]}],"id":[{"id":"https:\/\/ror.org\/02dyjk442","id-type":"ROR","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100013213","name":"Research Fund for Coal and Steel","doi-asserted-by":"publisher","award":["101157379-MiDSafe"],"award-info":[{"award-number":["101157379-MiDSafe"]}],"id":[{"id":"10.13039\/501100013213","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100004569","name":"Polish Ministry of Science and Higher Education","doi-asserted-by":"publisher","award":["6010\/FBWiS\/2024\/2025\/2"],"award-info":[{"award-number":["6010\/FBWiS\/2024\/2025\/2"]}],"id":[{"id":"10.13039\/501100004569","id-type":"DOI","asserted-by":"publisher"}]},{"award":["6010\/FBWiS\/2024\/2025\/2"],"award-info":[{"award-number":["6010\/FBWiS\/2024\/2025\/2"]}],"id":[{"id":"https:\/\/ror.org\/05dwvd537","id-type":"ROR","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Materials"],"abstract":"<jats:p>This study assessed the effects of groundwater interacting with aggregate produced from steel slag, used as a ballast material in a waterproofing system protecting the road surface under high groundwater table conditions. Field investigations were carried out, with hydrochemical analyses of groundwater and water draining through the structure, mineralogical characterisation of the slag, and geochemical modelling using the PHREEQC programme with inverse modelling. The results showed that water flow through the slag aggregate caused strong alkalisation of the solution and changes in the concentrations of Ca, Mg, Na, Cl, sulphates and carbonate components. Inverse modelling enabled the identification of eight acceptable mass balance models. The main primary phases involved in the transformations were larnite, merwinite, mayenite, halite and, locally, slag glass. Their dissolution contributed Ca, Mg, Al, Si, Na and Cl to the solution. The increases in Na and Cl concentrations were interpreted primarily as the result of an external influx of road salt, rather than as an intrinsic property of the slag. The secondary products were dominated by amorphous silica, calcite, ettringite and brucite, indicating silica removal, carbonation, sulphate fixation and the partial immobilisation of Mg. The results confirm that slag aggregate remains geochemically active in contact with groundwater; however, simultaneous carbonation and secondary mineralisation favour the gradual stabilisation of the water\u2013slag system.<\/jats:p>","DOI":"10.3390\/ma19163457","type":"journal-article","created":{"date-parts":[[2026,8,14]],"date-time":"2026-08-14T15:48:36Z","timestamp":1786722516000},"page":"3457","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Geochemical Effects of Groundwater Interaction with Steel Slag Aggregate Used in Road Construction"],"prefix":"10.3390","volume":"19","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-5925-4676","authenticated-orcid":false,"given":"Zdzis\u0142aw","family":"Adamczyk","sequence":"first","affiliation":[{"name":"Faculty of Mining, Safety Engineering and Industrial Automation, Silesian University of Technology, Ul. Akademicka 2, 44-100 Gliwice, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Aleksandra","family":"Czajkowska","sequence":"additional","affiliation":[{"name":"Faculty of Mining, Safety Engineering and Industrial Automation, Silesian University of Technology, Ul. Akademicka 2, 44-100 Gliwice, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6002-5475","authenticated-orcid":false,"given":"Barbara","family":"Bia\u0142ecka","sequence":"additional","affiliation":[{"name":"Department of Environmental Analysis and Circular Economy Technologies, Central Mining Institute\u2014National Research Institute, Plac Gwark\u00f3w 1, 40-166 Katowice, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4779-1263","authenticated-orcid":false,"given":"Magdalena","family":"Cempa","sequence":"additional","affiliation":[{"name":"Department of Environmental Analysis and Circular Economy Technologies, Central Mining Institute\u2014National Research Institute, Plac Gwark\u00f3w 1, 40-166 Katowice, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,8,14]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"285","DOI":"10.1016\/S0956-053X(00)00102-1","article-title":"Products of steel slags an opportunity to save natural resources","volume":"21","author":"Motz","year":"2001","journal-title":"Waste Manag."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"1576","DOI":"10.1021\/es9906002","article-title":"Physical and chemical characteristics of blast furnace, basic oxygen furnace, and electric arc furnace steel industry slags","volume":"34","author":"Proctor","year":"2000","journal-title":"Environ. 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