Treatment of water inflow from flooded underground mines

The study focuses on the adverse effect exerted on the environment by temporary shutdown and closure of underground mines by means of flooding. Closure of underground mines only terminates the structural and technological transformation of geological rock mass while detrimental effect on the natural environment of underground mines remains and even becomes more severe sometimes. Some hazards are revealed, which initiate new phenomena and processes, and are mainly connected with flooding of underground mines. Such hazards are groundwater rise, flow of water from flooded mines to operating mines, ground surface deformation due to subsidence and entry of pollutants in underground aquifers and surface water bodies. In terms of a flooded mine in East Donbass, the method of catchment of water outlet from the flooded mine and dispersion to a man-made biological pond is described. The biological pond is split into zones. First, there is a shallow place with planting for activation of growth of iron bacteria; here, removal of iron ions from mine water takes place. Then, water flows to the pond for the further bio-oxidation and treatment of water up to the standard MAC. The article offers recommendations on making of the biological pond and a trench for water flow from mine. The required volumes and sizes of the biological pond, trench and activation zone for iron bacteria are calculated. Treated mine water, via a dam, will be fed to a water storage reservoir.

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Multi-Sensor InSAR Assessment of Ground Deformations around Lake Mead and Its Relation to Water Level Changes

Remote Sensing ◽

10.3390/rs13030406 ◽

2021 ◽

Vol 13 (3) ◽

pp. 406

Author(s):

Mehdi Darvishi ◽

Georgia Destouni ◽

Saeid Aminjafari ◽

Fernando Jaramillo

Keyword(s):

Water Level ◽

Surface Deformation ◽

Ground Deformation ◽

Water Storage ◽

Negative Relationship ◽

Ground Surface ◽

Subsurface Water ◽

Lake Mead ◽

Ground Deformations ◽

Water Level Changes

Changes in subsurface water resources might alter the surrounding ground by generating subsidence or uplift, depending on geological and hydrogeological site characteristics. Improved understanding of the relationships between surface water storage and ground deformation is important for design and maintenance of hydraulic facilities and ground stability. Here, we construct one of the longest series of Interferometric Synthetic Aperture Radar (InSAR) to date, over twenty-five years, to study the relationships between water level changes and ground surface deformation in the surroundings of Lake Mead, United States, and at the site of the Hoover Dam. We use the Small Baseline Subset (SBAS) and Permanent scatterer interferometry (PSI) techniques over 177 SAR data, encompassing different SAR sensors including ERS1/2, Envisat, ALOS (PALSAR), and Sentinel-1(S1). We perform a cross-sensor examination of the relationship between water level changes and ground displacement. We found a negative relationship between water level change and ground deformation around the reservoir that was consistent across all sensors. The negative relationship was evident from the long-term changes in water level and deformation occurring from 1995 to 2014, and also from the intra-annual oscillations of the later period, 2014 to 2019, both around the reservoir and at the dam. These results suggest an elastic response of the ground surface to changes in water storage in the reservoir, both at the dam site and around the reservoir. Our study illustrates how InSAR-derived ground deformations can be consistent in time across sensors, showing the potential of detecting longer time-series of ground deformation.

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Imaging ground surface deformations in post-disaster settings via small UAVs

Geoscience Letters ◽

10.1186/s40562-021-00194-8 ◽

2021 ◽

Vol 8 (1) ◽

Author(s):

Richard L. Ybañez ◽

Audrei Anne B. Ybañez ◽

Alfredo Mahar Francisco A. Lagmay ◽

Mario A. Aurelio

Keyword(s):

Surface Deformation ◽

Ground Surface ◽

Point Clouds ◽

Lateral Spreading ◽

Fault Movement ◽

Field Surveys ◽

3D Point Clouds ◽

Vertical Displacements ◽

Resolution Imaging ◽

Post Disaster

AbstractSmall unmanned aerial vehicles have been seeing increased deployment in field surveys in recent years. Their portability, maneuverability, and high-resolution imaging are useful in mapping surface features that satellite- and plane-mounted imaging systems could not access. In this study, we develop and apply a workplan for implementing UAV surveys in post-disaster settings to optimize the flights for the needs of the scientific team and first responders. Three disasters caused by geophysical hazards and their associated surface deformation impacts were studied implementing this workplan and was optimized based on the target features and environmental conditions. An earthquake that caused lateral spreading and damaged houses and roads near riverine areas were observed in drone images to have lengths of up to 40 m and vertical displacements of 60 cm. Drone surveys captured 2D aerial raster images and 3D point clouds leading to the preservation of these features in soft-sedimentary ground which were found to be tilled over after only 3 months. The point cloud provided a stored 3D environment where further analysis of the mechanisms leading to these fissures is possible. In another earthquake-devastated locale, areas hypothesized to contain the suspected source fault zone necessitated low-altitude UAV imaging below the treeline capturing Riedel shears with centimetric accuracy that supported the existence of extensional surface deformation due to fault movement. In the aftermath of a phreatomagmatic eruption and the formation of sub-metric fissures in nearby towns, high-altitude flights allowed for the identification of the location and dominant NE–SW trend of these fissures suggesting horst-and-graben structures. The workplan implemented and refined during these deployments will prove useful in surveying other post-disaster settings around the world, optimizing data collection while minimizing risk to the drone and the drone operators.

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3D Visual Technology of Geo-Deformation Disasters Induced by Mining Subsidence Based on ArcGIS Engine

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.500.428 ◽

2012 ◽

Vol 500 ◽

pp. 428-436 ◽

Cited By ~ 2

Author(s):

Ke Ming Yang ◽

Jun Ting Ma ◽

Bo Pang ◽

Yi Bin Wang ◽

Ran Wang ◽

...

Keyword(s):

Coal Mining ◽

Surface Deformation ◽

Ground Deformation ◽

Ground Surface ◽

Horizontal Displacement ◽

Mining Subsidence ◽

Underground Coal Mining ◽

Vertical Movements ◽

Probability Integral Method ◽

Arcgis Engine

Mining subsidence often produces significant horizontal and vertical movements at the ground surface, the surface deformation induced by underground coal mining can be predicted by probability integral method, and the surface geo-deformation disasters can be visualized based on GIS components. A three dimensional (3D) visualizing system of surface geo-deformation information is designed and developed with ArcGIS Engine and C# in the study. According to the surface deformation-predicted data induced by underground coal mining in Guobei Coalmine of Huaibei mine field, the extents and degrees of ground deformation disasters are visualized in 3D views for surface vertical subsidence, slope, curvature, horizontal displacement and horizontal strain based on the GIS-developed application platform.

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