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Over the past half century, the demand for sand and gravel has led to extensive quarrying activities, creating many pit lakes (PLs) which now dot floodplains and urbanized regions globally. Despite the potential importance of these environments, systematic data on their location, morphology and water quality remain limited. In this study, we present an extensive assessment of the physical and optical properties in a large sample of PLs located in the Po River basin (Italy) from 1990 to 2021, utilizing a combined approach of remote sensing (Landsat constellation and Sentinel-2) and traditional limnological techniques. Specifically, we focused on the concentration of Suspended Particulate Matter (SPM) and the dominant wavelength (λdom, i.e., water colour). This study aims to contribute to the analysis of PLs at a basin scale as an opportunity for environmental rehabilitation and river floodplain management. ACOLITE v.2022, a neural network particularly suitable for the analysis of turbid waters and small inland water bodies, was used to atmospherically correct satellite images and to obtain SPM concentration maps and the λdom. The results show a very strong correlation between SPM concentrations obtained in situ and those obtained from satellite images, both for data derived from Landsat (R2 = 0.85) and Sentinel-2 images (R2 = 0.82). A strong correlation also emerged from the comparison of spectral signatures obtained in situ via WISP-3 and those derived from ACOLITE, especially in the visible spectrum (443–705 nm, SA = 10.8°). In general, it appeared that PLs with the highest mean SPM concentrations and the highest mean λdom are located along the main Po River, and more generally near rivers. The results also show that active PLs exhibit a poor water quality status, especially those of small sizes (<5 ha) and directly connected to a river. Seasonal comparison shows the same trend for both SPM concentration and λdom: higher values in winter gradually decreasing until spring–summer, then increasing again. Finally, it emerged that the end of quarrying activity led to a reduction in SPM concentration from a minimum of 43% to a maximum of 72%. In this context, the combined use of Landsat and Sentinel-2 imagery allowed for the evaluation of the temporal evolution of the physical and optical properties of the PLs in a vast area such as the Po River basin (74,000 km2). In particular, the Sentinel-2 images consistently proved to be a reliable resource for capturing episodic and recurring quarrying events and portraying the ever-changing dynamics of these ecosystems.

Mining and quarrying for minor minerals impart significant economic, environmental and social impacts in and around the affected areas. The problem is severe in the small river catchments as the effective area available for assimilating negative impacts of the activity is minimal, compared to large river basins. To address these issues, an investigation has been carried out in two river basins of southern Western Ghats (India)—the Netravati–Gurpur and Periyar–Chalakudy river basins. Both these basins host two important port cities of south India—Kochi and Mangalore. The study reveals that about 6.75 × 106 ty−1 of hard rocks are being extracted in the Netravati–Gurpur basin through 64 quarries. At the same time, the total number of quarries and extracted amounts in the Periyar–Chalakudy river basin are 525 and 10.47 × 106 ty−1, respectively. Many hillocks in the region are turned to a cluster of ugly scars, degrading the ecology and aesthetics of the area. Lowering of water table, modification or disappearance of natural drainages and environmental pollution are some of the other observations noticed in the area. The environmental impacts of laterite quarrying are comparatively less than that of rock quarrying as removal of the hard laterite cap rock enhances water percolation and makes the area more irrigable for agriculture. The study stresses the need for environment-friendly quarrying alternatives with stringent guidelines to improve the overall environmental quality of the area on one hand and to meet the developmental requirements on the other.

In this study, we investigated the impact of quarrying as an environmental ethical crisis. The need for the study arose when we realised the deteriorating effect of the quality of life in our community, which is located next to a limestone quarry. To obtain a deeper understanding of the adverse impact on the environment and the quality of life of the people living in the community around the quarry, we explored the workers from the community, and the members of the community-based organisation’s (CBO) experiences. We employed a qualitative method research approach, using a single case study design. We adopted a utilitarian perspective and Pinchot’s conservation as ethical systems that determine morality based on the greatest good for the greatest number. Both provide a framework for analysing environmental problems and ethical crises associated with limestone quarrying. We generated data using face-to-face interviews and focus group discussions. We present and discuss data through the following themes: analysis of the social and cultural impacts on local communities and indigenous people, assessment of the ecological consequences on biodiversity and habitat destruction, and examination of the effects on water resources, air quality, and soil erosion. The results show that the negative effects of the quarry on the environment have always worried the local people. The company’s disrespect for the community and ignorance of the laws governing quarry activities is the root of the ethical dilemma. The detrimental effects that the operations have on human health and safety as well as the environment is the other ethical dilemma, which includes, land degradation, vibrations, air, and water pollution.

The Effective utilization and recycling of resources have become important issues all over the world. Dewatered cake is an industrial by-product generated from water treatment of quarrying, and approximately 50 million tons are produced annually in Japan, with about 35% unable to be effectively utilized and disposed of in landfilling. In Japan, securing landfill sites has become a significant issue, and the disposal cost is increasing, leading to a growing need for new methods of effective utilization. Geopolymer material has attracted attention due to its higher resistance to acid and heat than ordinary Portland cement (OPC). In this study, we attempted to prepare geopolymer cement from dehydrated cake using alkali fusion with NaOH and KOH. Stone cake, discharged from one of the quarries in Japan, was fused with alkali hydroxides with different ratio of NaOH to KOH at 200 – 500 °C for 1.5 h to obtain the fused cake with high soluble contents of Si and Al, and the fused cake, raw cake and water were mixed at various ratios to heat at 80 °C for 24 h to produce the geopolymer materials. With increasing KOH addition and heating temperature on alkali fusion, the alkali fusion reaction was promoted, and the highest reaction rate is indicated using alkali hydroxide with NaOH: KOH = 1:3. The geopolymer prepared from the fused cake with KOH: NaOH = 1:3 showed the same strength as OPC. The prepared geopolymer has higher resistance to acid and heat than OPC.

Glacial erosion creates diagnostic landscapes and vast amounts of sediment. However, knowledge about the rate at which glaciers erode and sculpt bedrock and the proportion of quarried (plucked) versus abraded material is limited. To address this, we quantify subglacial erosion rates and constrain the ratio of quarrying to abrasion during a recent, ⼠200-year long overriding of a bedrock surface fronting, Sermeq Kujalleq (Jakobshavn Isbræ), Greenland, by combining .sup.10 Be analyses, a digital terrain model, and field observations. Cosmogenic .sup.10 Be measurements along a 1.2 m tall quarried bedrock step reveal a triangular wedge of quarried rock. Using individual .sup.10 Be measurements from abraded surfaces across the study area, we derive an average abrasion rate of 0.13 ± 0.08 mm yr.sup.-1 . By applying this analysis across a ⼠1.33 km.sup.2 study area, we estimate that the Greenland Ice Sheet quarried 378 ± 45 m.sup.3 and abraded 322 ± 204 m.sup.3 of material at this site. These values result in an average total erosion rate of 0.26 ± 0.16 mm yr.sup.-1, with abrasion and quarrying contributing in roughly equal proportions within uncertainty. Additional cosmogenic .sup.10 Be analysis and surface texture mapping indicate that many lee steps are relicts from the prior glaciation and were not re-quarried during the recent overriding event. These new observations of glacier erosion in a recently exposed landscape provide one of the first direct measurements of quarrying rates and indicate that quarrying accounts for roughly half of the total glacial erosion in representative continental shield lithologies.

Glacial quarrying stems from the fracturing of subglacial bedrock. Much evidence shows that subcritical crack propagation of bedrock is closely related to subglacial water pressure fluctuations. Here we employ a model that assesses the impact of subglacial water pressure fluctuation on cavity length and subcritical crack propagation, while analyzing the effect of a pre-existing crack location using a phase-field model (PFM). Our results indicate that the cavity length is reduced during diurnal fluctuations in water pressure. There are two patterns of subcritical crack propagation on the corner of the step. The first stems from a rapid drop in water pressure. The second occurs after the water pressure recovers from the fluctuation to the initial steady state. This pattern is a consequence of enhanced stress concentration on the step since the modeled cavity length exceeds its steady value and has higher efficiency in promoting subcritical crack propagation. Additionally, based on the PFM results, we speculate that the subcritical crack initiation and propagation happen on a broader scale, including the ice-bed contact region and its adjacent region. Our findings imply that the duration of subcritical crack propagation is short and typically ceases once the cavity length adjusts to reduced water pressure levels.

Geologists and archaeologists have long known that the bluestones of Stonehenge came from the Preseli Hills of west Wales, 230km away, but only recently have some of their exact geological sources been identified. Two of these quarries—Carn Goedog and Craig Rhos-y-felin—have now been excavated to reveal evidence of megalith quarrying around 3000 BC—the same period as the first stage of the construction of Stonehenge. The authors present evidence for the extraction of the stone pillars and consider how they were transported, including the possibility that they were erected in a temporary monument close to the quarries, before completing their journey to Stonehenge.

Hard rocks or crystalline rocks (i.e., plutonic and metamorphic rocks) constitute the basement of all continents, and are particularly exposed at the surface in the large shields of Africa, India, North and South America, Australia and Europe. They were, and are still in some cases, exposed to deep weathering processes. The storativity and hydraulic conductivity of hard rocks, and thus their groundwater resources, are controlled by these weathering processes, which created weathering profiles. Hard-rock aquifers then develop mainly within the first 100 m below ground surface, within these weathering profiles. Where partially or noneroded, these weathering profiles comprise: (1) a capacitive but generally low-permeability unconsolidated layer (the saprolite), located immediately above (2) the permeable stratiform fractured layer (SFL). The development of the SFL’s fracture network is the consequence of the stress induced by the swelling of some minerals, notably biotite. To a much lesser extent, further weathering, and thus hydraulic conductivity, also develops deeper below the SFL, at the periphery of or within preexisting geological discontinuities (joints, dykes, veins, lithological contacts, etc.). The demonstration and recognition of this conceptual model have enabled understanding of the functioning of such aquifers. Moreover, this conceptual model has facilitated a comprehensive corpus of applied methodologies in hydrogeology and geology, which are described in this review paper such as water-well siting, mapping hydrogeological potentialities from local to country scale, quantitative management, hydrodynamical modeling, protection of hard-rock groundwater resources (even in thermal and mineral aquifers), computing the drainage discharge of tunnels, quarrying, etc.

The visual impact of the chromatic contrast between quarry faces and rocky outcrops represents one of the prominent disturbances to natural environments. This study, therefore, aims to quantify color changes over time in quarries by analyzing three faces of an active limestone quarry in Santullán, Cantabria, that were exposed to atmospheric conditions in 1978, 2003 and 2021. To achieve this, the contribution of biological colonisation to natural darkening, along with the physicochemical changes occurring on the quarry faces, have been evaluated using scanning electron microscopy in secondary and backscattered electron mode, UV–Vis spectrophotometric techniques, Raman spectroscopy and XRD and XRF analysis. The analysis revealed that the color change was primarily due to microbial colonisation rather than oxidative chemical reactions. Although color change does not follow a direct and progressive relationship with exposure time, biological colonisation, identified primarily as microbial communities dominated by phototrophic microorganisms, shows a clear increase in microbial presence, bioalteration, and penetration into the rock substrate in older samples. The most significant visual changes appear to occur during the first years of exposure of the massif to atmospheric conditions.

The environmental impacts of mining, quarrying, and the stone processing industry are significant, affecting air quality, health, and the socioeconomic status of communities worldwide. Key contributors to air pollution include the waste of raw materials from quarrying, non-compliance with scientific protocols, and the extraction of natural mineral resources. The rapid increase in pollution sources, such as dust, water, and noise, has led to the release of various pollutants into the atmosphere, degrading local air quality. This study conducted sampling at twelve sites, adhering to the Central Pollution Control Board’s (CPCB) monitoring guidelines. Twelve metrics, including PM10, PM2.5, SO2, NOx, CO, O3, Pb, NH3, C6H6, C2OH12, As, and Ni, were measured twice a week over a three-month period (January 2024 to March 2024) by the National Ambient Air Quality Standards (NAAQS) in the research area. The results indicated that while SO2 and NOx levels were within permissible limits at all monitored locations, Suspended Particulate Matter (SPM) levels were high at every station. The average baseline levels of PM10 (37.17 μg/m³ to 70.52 μg/m³), PM2.5 (16.98 μg/m³ to 39.85 μg/m³), SO2 (5.29 μg/m³ to 13.91 μg/m³), NOx (9.8 μg/m³ to 29.71 μg/m³), CO (0.15 mg/m³ to 0.32 mg/m³), O3 (6.9 μg/m³ to 15.37 μg/m³), and NH3, Pb, Ni, As, C2OH12, and C6H6 were below the detection levels (BDL) and limits of quantification (LOQ), all within the National Ambient Air Quality Standards for commercial, industrial, and residential areas during the study period. This research highlights the urgent need for effective pollution control measures to mitigate the adverse environmental and health impacts of these industries.