Mining, Volume 4, Issue 3 (September 2024) – 4 articles

Underground hydrogen storage (UHS) is considered to solve the intermittency problem of renewable energy. A geological assessment indicated that the B unit of the Salina Group in Southern Ontario, Canada, is the most promising for UHS because it is the thickest and most regionally extensive salt rock deposit. However, the comprehensive geological knowledge of potential sites and overall salt volume for UHS remains undiscovered. This paper collected 1112 wells’ logging data to assess the geologic potential for UHS in Lambton County. The geological characteristic analysis of the B unit was conducted using high-frequency stratigraphic sequences and logging interpretation. The internal lithologies and thicknesses of the B unit were interpreted from 426 available wells. The storage capacity of the salt caverns was calculated from simplified cylinder models. The results indicate that the B unit can be subdivided into three high-frequency sequences, denoted as the SQ1, SQ2, and SQ3 subunits. SQ1 corresponds to salt–limestone, SQ2 corresponds to bedded salt rocks, and SQ3 corresponds to massive salt rocks. Well sections and thickness maps indicate that the study area can be divided into two sub-areas along the Wilikesport, Oil Spring, and Watford line. To the northwest, unit B was thicker and deeper in terms of paleo-water depth, and to the southeast, less of the B unit was deposited on the paleo-highs. The main thicknesses in SQ1, SQ2, and SQ3 range from 20 to 30 m, 25 to 35 m, and 30 to 40 m, respectively. In conclusion, the best subunit for UHS is SQ3, with a secondary target being SQ2. The main factor impacting cavern storage capacity for the SQ2 subunit is high mud content, while for SQ3, it is the meters-thick anhydrite developed towards the base of the unit. The available underground storage volume of the salt caverns in the B unit is 9.10 × 10⁶ m³. At the standard state, the working gas volume is 557.80 × 10⁶ m³. The favorable area for UHS is the western part surrounded by Wallaceburg, Oil Spring, and Watford. The thickness distribution of the B unit is the combined result of paleo-topography, sea-level changes, and tectonic movement in Lambton. The geological storage capacity of the salt caverns exhibits significant potential. Full article

Artisanal and small-scale gold mining (ASGM) has made several environmental impacts, resulting in the significant siltation of water bodies due to the deposition of sediments on riverbanks. Based on this perspective, this study aims to investigate the water bodies and regions most impacted by mining activities, especially in relation to the increase in the Total Suspended Solids (TSS) caused by ASGM, focusing on the territories of Suriname and French Guiana, over the period from 2017 to 2023, through the creation of an algorithm in Google Earth Engine. This research also aims to map and describe active mining in this region using the Classification and Regression Tree (CART) method, which achieved an overall accuracy of 82% and a kappa index of 0.77. The results reveal that from 2017 to 2024, there was an increase of 148.09 km² in mining, with an average increase in TSS of up to 167 mg/L in water bodies most affected by mining activities. Finally, the continued importance of using remote sensing technologies, such as GEE, together with innovative methodological approaches, to monitor and manage natural resources in a sustainable manner is highlighted. Full article

Heritage and culture tourism involve features that commemorate a valued past. Mining heritage tourism allows visitors to experience the past, guided by former mining landscapes and engaging interactively with material artifacts. This paper introduces the CoalHeritage European project, focusing on the promotion of coal mining heritage through the production and design of the European Visual Map Journal (EVMJ). The EVMJ is a user-friendly, web-based, interactive storytelling platform that supports the transfer of industrial and geoheritage from former coal mining areas. It aims to collect and disseminate heritage assets from post-mining coal areas, informing stakeholders and promoting these sites as tourist destinations. To further enhance public awareness, several ESRI StoryMaps web apps are being created to highlight specific features of each case study across Europe. The aim of this work is to introduce coal mining heritage as a new term, present the coal heritage platform and its importance for disseminating coal heritage aspects to the public, describe the methodology used for its design, and provide a brief overview of its evolving content. Full article

Groundwater quality can be impacted by the backfilling of coal pits with waste rock containing new mineral surfaces and nanomaterials. This study was implemented to identify newly available arsenic and selenium sources in waste rock from the Cordero Rojo Mine in the Powder River Basin, Wyoming, to highlight the alteration of contaminant sources with the transition from an overburden geologic state to the mined waste rock. Basic kinetic models were constructed to replicate the possible weathering modeling scenario derived from published sources of arsenic and selenium in the Powder River Basin overburden—pyrite and gypsum, respectively. These basic prediction models were unable to capture the arsenic and selenium trends recorded for a saturated column loaded with waste rock from the Cordero Rojo Mine. Enhanced kinetic models were tested through trial and error to capture newly available sources created by the mining of the waste rock. The incorporation of new source contributions produced modeled arsenic and selenium trends similar to the observed trends in water extracted from the column. The identification of newly available contaminant sources in backfill waste rock is necessary to evaluate the potential release of contaminants and the exceedance of water quality criteria for overburden formations that have not previously shown the potential for water quality contamination. Full article