Hazardous Elements in Sediments Detected in Former Decommissioned Coal Mining Areas in Colombia: A Need for Environmental Recovery

Abstract

This study demonstrates an investigation into nanomineralogical and geochemical evolution for the detection of hazardous elements from old, abandoned coal mining deposits capable of causing negative environmental impacts. The general objective of this study is to evaluate the number of nanoparticulate chemical elements in sediments collected during the years 2017 and 2022 from deactivated coal mining areas in the La Guajíra and Cesar regions of Colombia. Sediments were collected and analyzed from areas that experienced spontaneous coal combustion (SCC). The analysis consisted of traditional mineralogical analysis by X-ray diffraction and Raman spectroscopy, nanomineralogy by field emission scanning electron microscope-FE-SEM, and high-resolution transmission electron microscope-HR-TEM (energy dispersive X-ray microanalysis system-EDS). The analyzed sediment samples contained high proportions of amorphous materials containing the chemical elements As, Cl, Hg, Mo, Pb, Sb, and Se. This study emphasizes the need to implement environmental recovery projects at former, now abandoned coal extraction areas located in the investigated region, as they have negative effects on the environment and human health across large regions.

Cement Stabilization of Waste from Contaminated Soils in Terms of Its Installation into Engineered Landfill

“…Such sites can be located underground [7] or aboveground [8,9]. The crucial issue concerning aboveground storage facilities is the protection of groundwaters [10][11][12].…”

Nanomineral and Their Importance on the Earth and Human Health: A Real Impact

“…A more detailed assessment of particles that contain rare-earth elements (REEs) in abandoned deposits of Brazilian fine coal tailings (BFCTs) was carried out to aid the current coal mining industries in the identification of methodologies for extracting such elements (Santa Catarina State, Brazil and Colombia) [1,2]. The BFCT areas were sampled for traditional mineralogical analysis by X-ray diffraction, Raman spectroscopy and nanomineralogy by a dual beam focused ion beam (FIB) coupled with field emission scanning electron microscopy (FE-SEM) and high-resolution transmission electron microscopy (HR-TEM) coupled with an energy dispersive X-ray microanalysis system (EDS).…”

“…This makes it significantly easier for REEs to be extracted. In addition, owing to their proximity to roads and rail transport in the regions under study [2], the opportunity exists for such resources (BFCTs) to be utilized as a secondary market as opposed to simply being discarded, which has been the case in the past [3]. Particulates in the nanoparticle and ultra-fine particle range are being released from uncontrolled coal fires and may be impacting the environment and the health of the mine workers and nearby residents, an issue that should be investigated [3].…”