An extraction well system is disclosed that allows for isolation of electrical cables from underground mine atmosphere. The extraction well system provides for a well casing that extends downwardly proximate to an existing mine cavity and an extension casing that extends downwardly below the mine roof. In one embodiment the extension casing is external to the well casing and is attached to the well casing mechanically such as with a dual thread reducer. The extension runs from above the mine roof to below the mine floor and is perforated in the area of the mine cavity to allow liquid to drain into the bottom of the extension well. In a second embodiment, the extension casing is interior to the well casing and is attached for example by an internal liner hanger. In this embodiment, the extension casing runs from above the mine roof to below the desired minimum liquid level and it is the well casing that extends downwardly in the extension well and which is perforated to allow liquids to flow into the well.

An extraction well system is disclosed that allows for isolation of electrical cables from underground mine atmosphere. The extraction well system provides for a well casing that extends downwardly proximate to an existing mine cavity and an extension casing that extends downwardly below the mine roof. In one embodiment the extension casing is external to the well casing and is attached to the well casing mechanically such as with a dual thread reducer. The extension runs from above the mine roof to below the mine floor and is perforated in the area of the mine cavity to allow liquid to drain into the bottom of the extension well. In a second embodiment, the extension casing is interior to the well casing and is attached for example by an internal liner hanger. In this embodiment, the extension casing runs from above the mine roof to below the desired minimum liquid level and it is the well casing that extends downwardly in the extension well and which is perforated to allow liquids to flow into the well.

The present invention relates to a ground double-hole combined water inrush prevention method for overlying strata movement monitoring and bed separation water drainage. By arranging a rock strata movement monitoring borehole and a bed separation water drainage borehole, interior movement information of an overlying stratum and bed separation generation timing fed back by strata movement monitoring performed inside are monitored; work on the bed separation water drainage borehole is guided by monitoring changes in arranged monitoring points; and through combination of the movement monitoring borehole and the bed separation water drainage borehole, the utilization rate of the bed separation water drainage borehole is effectively increased.

A method for constructing a dam inside a dump of an inner-dump strip mine includes: taking an upper surface connection line of a primary water-resisting layer as upper filling reference datum boundary of an artificial water-resisting layer; arranging a dam foundation pit and a trapezoidal abutment on a midline of the dam foundation pit; building and reinforcing a step-shaped retaining dam core wall on the artificial water-resisting layer; laying a foundation impervious layer, waterproof geotextile, and an earth blanket on one side, close to the primary aquifer, of the retaining dam core wall; strengthening advance of a dumping working face on one side, away from the primary aquifer, of the retaining dam core wall, and dumping overburden of a strip mine to form a support; filling a space between the earth blanket and the primary aquifer to form a blocker; and proceeding with construction and forming a continuous retaining dam.

A method for constructing a dam inside a dump of an inner-dump strip mine includes: taking an upper surface connection line of a primary water-resisting layer as upper filling reference datum boundary of an artificial water-resisting layer; arranging a dam foundation pit and a trapezoidal abutment on a midline of the dam foundation pit; building and reinforcing a step-shaped retaining dam core wall on the artificial water-resisting layer; laying a foundation impervious layer, waterproof geotextile, and an earth blanket on one side, close to the primary aquifer, of the retaining dam core wall; strengthening advance of a dumping working face on one side, away from the primary aquifer, of the retaining dam core wall, and dumping overburden of a strip mine to form a support; filling a space between the earth blanket and the primary aquifer to form a blocker; and proceeding with construction and forming a continuous retaining dam.

The present invention provides a fissured substrata water pumping apparatus and methods thereof. The fissured substrata water pumping apparatus includes a water pumping pipe inserted into a drilled hole under a roadway floor; one or more unidirectional water-blocking plates configured inside the water pumping pipe; a servo pump; and an annular drainage siphon having a first end connected to an upper end of the water pumping pipe, and a second end connected to an inlet end of the servo pump through a valve.

The present invention provides a fissured substrata water pumping apparatus and methods thereof. The fissured substrata water pumping apparatus includes a water pumping pipe inserted into a drilled hole under a roadway floor; one or more unidirectional water-blocking plates configured inside the water pumping pipe; a servo pump; and an annular drainage siphon having a first end connected to an upper end of the water pumping pipe, and a second end connected to an inlet end of the servo pump through a valve.

A method for constructing a dam inside a dump of an inner-dump strip mine includes: taking an upper surface connection line of a primary water-resisting layer as upper filling reference datum boundary of an artificial water-resisting layer; arranging a dam foundation pit and a trapezoidal abutment on a midline of the dam foundation pit; building and reinforcing a step-shaped retaining dam core wall on the artificial water-resisting layer; laying a foundation impervious layer, waterproof geotextile, and an earth blanket on one side, close to the primary aquifer, of the retaining dam core wall; strengthening advance of a dumping working face on one side, away from the primary aquifer, of the retaining dam core wall, and dumping overburden of a strip mine to form a support; filling a space between the earth blanket and the primary aquifer to form a blocker; and proceeding with construction and forming a continuous retaining dam.

A method for constructing a dam inside a dump of an inner-dump strip mine includes: taking an upper surface connection line of a primary water-resisting layer as upper filling reference datum boundary of an artificial water-resisting layer; arranging a dam foundation pit and a trapezoidal abutment on a midline of the dam foundation pit; building and reinforcing a step-shaped retaining dam core wall on the artificial water-resisting layer; laying a foundation impervious layer, waterproof geotextile, and an earth blanket on one side, close to the primary aquifer, of the retaining dam core wall; strengthening advance of a dumping working face on one side, away from the primary aquifer, of the retaining dam core wall, and dumping overburden of a strip mine to form a support; filling a space between the earth blanket and the primary aquifer to form a blocker; and proceeding with construction and forming a continuous retaining dam.

A system and method for removing water from mine areas. In one embodiment, one or more directionally drilled dewatering wells are drilled into the geologic formation such that at least a portion of the dewatering well is positioned underneath the mine. In one embodiment, one or more of the dewatering wells may originate outside the perimeter of the mine so as not to interfere with mine operations. In one embodiment, a hydrogeologic assessment along with mine dewatering requirements may be used to generate a mine dewatering plan. In one embodiment, a hydrogeologic assessment along with a determination of the dewatering requirements of the mine and surrounding areas may be used to create a mine dewatering plan. In one embodiment, the mine dewatering plan provides design information pertaining to each dewatering well.