Use of fly ash layer as a barrier to prevent contamination of rainwater by contact with Hg-contaminated debris

Highly contaminated waste from an old mercury mine facility was covered with fly ash from a coal-burning power plant that was analyzing the rainwater infiltration in a full-scale test in which the influencing variables were monitored for a year. A sufficiently low hydraulic conductivity and sufficie...

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Bibliographic Details
Authors: Rodríguez Díez, Rafael, Bascompta Massanes, Marc|||0000-0003-1519-6133, García Ordiales, Efran, Ayala, Julia
Format: article
Publication Date:2025
Country:España
Institution:Universitat Politècnica de Catalunya (UPC)
Repository:UPCommons. Portal del coneixement obert de la UPC
Language:English
OAI Identifier:oai:upcommons.upc.edu:2117/428126
Online Access:https://hdl.handle.net/2117/428126
https://dx.doi.org/10.3390/environments12040107
Access Level:Open access
Keyword:Fly ash
Physical remediation
Abandoned mines
Pollution
Water contamination
Àrees temàtiques de la UPC::Enginyeria civil::Enginyeria de mines::Explotació de mines
Àrees temàtiques de la UPC::Desenvolupament humà i sostenible::Degradació ambiental
Description
Summary:Highly contaminated waste from an old mercury mine facility was covered with fly ash from a coal-burning power plant that was analyzing the rainwater infiltration in a full-scale test in which the influencing variables were monitored for a year. A sufficiently low hydraulic conductivity and sufficiently high porosity of the ash, and the relationship between evapotranspiration and precipitation were the most important factors controlling rainwater infiltration through the fly ash layer to produce contaminated leachate. A fly ash layer with a thickness between 10 and 50 cm, depending on climatic conditions, works as a barrier to partially or totally prevent, depending on the scenario considered, rainwater contamination. Overall, the solution proposed in this study results in economic savings in all the cases considered, because treatments for eliminating PTEs from waste are usually expensive. On the other hand, the effect is permanent over time, as it is based on a physical barrier effect, while the contamination reduction is independent of the initial concentration and the contamination reduction is for any PTE (Hg, Pb, Zn, etc.).