KR101936589B1 - Structure and Method for Preventing Sea Water Penetration to Well - Google Patents

Abstract

The present invention relates to a salinity increase prevention structure to prevent groundwater from being contaminated by salinity penetrated into a groundwater well, which is easily installed in an area having a salt wedge increase effect to effectively block horizontal and vertical movement of salt so as to prevent contamination of the groundwater well when a groundwater well is installed in the ground and fresh groundwater is pumped up to use fresh groundwater in a seaside aquifer, and a salinity blocking construction method for a groundwater well using the same. More specifically, according to the present invention, the salinity increase prevention structure has a polygonal cone shape with both opened upper and lower surfaces, and the lower surface smaller than the upper surface, and is buried in a fresh groundwater layer above a boundary surface between fresh groundwater and saline groundwater in a boring position of a groundwater well to be placed in a salinity moving path when the salinity is moved by the salt wedge increase effect, thereby blocking movement of the salinity to prevent the salinity from flowing to the groundwater well.

Description

Technical Field [0001] The present invention relates to a structure for prevention of contamination of groundwater due to salinity infiltration into a groundwater well, and a salt infiltration barrier construction method using the same,

The present invention relates to a salt build-up structure for preventing groundwater contamination due to salinity infiltration into a groundwater well, and to a saltwater infiltration barrier construction method for a groundwater well using the same, and more particularly, , It is possible to effectively prevent the salt from moving in the vertical direction as well as in the horizontal direction by preventing the contamination of the groundwater well by installing the groundwater well in the area where the saline wedge rises. And a construction method for effectively preventing salt infiltration of groundwater by installing a structure for preventing the increase of salt groundwater in the ground.

In order to utilize groundwater as a water source, a groundwater well is formed in the ground. Due to the increase of the salinity concentration of the groundwater due to seawater penetration into the groundwater well, the water from the groundwater well is contaminated and the groundwater well becomes useless. This contamination of the groundwater well by seawater intrusion is caused by the "brine wedge rise" phenomenon. In coastal aquifers, where freshwater-derived groundwater ("underground water") originates from the sea and groundwater ("saltwater groundwater" There is a natural "salt wedge". 1 is a schematic cross-sectional view of a ground for explaining the saltwater wedge phenomenon. In Figure 1, the dotted line B is the interface (B) between the groundwater and saltwater ground. The red arrow (S) indicates the flow of saltwater and the blue arrow (G) . In the coastal aquifer, the saltwater groundwater pierces the aquifers of the groundwater in the form of a wedge so as to have the interface (B) as shown in FIG. 1, so that the saltwater ground wedge- Wedge ". Saltwater wedges are also referred to as "seawater infiltration".

However, when the groundwater is pumped to the groundwater in order to utilize the groundwater in the coastal aquifer, salinity of the saline groundwater intercepted at the interface (B) between the groundwater and the saline groundwater, As a result of the flow disturbance, the phenomenon of "brine wedge rise due to the positive water" which moves upward in the direction of the ground water channel beyond the boundary position occurs, thereby increasing the salt concentration in the groundwater at the groundwater location. Fig. 2 is a schematic cross-sectional view of the ground corresponding to Fig. 1 showing the rise of the brine wedge. Fig. 3 shows the groundwater flow disturbance in the coastal aquifers due to groundwater development Is a schematic diagram showing the result of the simulation showing that this occurs. In Fig. 3, the red part is saline groundwater (seawater), the blue part is saline free groundwater, and the area marked from yellow to cyan is the area where salt groundwater and groundwater are mixed. In FIG. 3, as in FIG. 2, it can be seen that the saline wedge rises at the lower end of the groundwater well.

As shown in FIG. 2 and FIG. 3, as the salt water wedge rises due to the positive water, the saline flow path is gathered at the point where the ground water is pumped. Therefore, It is not wide and is characterized by concentration of salinity transfer route near groundwater well. The small dots inside the dashed circle labeled " rising point of the brine wedge "in FIG. 2 indicate the salt dissolved in the salt groundwater. As used herein, "salt" is used to refer to a substance dissolved in salt groundwater.

Therefore, in order to prevent the contamination of the groundwater caused by salt groundwater, it is necessary to prevent the increase of the salinity concentration in the groundwater pumped through the groundwater well by blocking the path of salinity transfer caused by the salt wedge phenomenon . However, in the prior art, it is only proposed to construct a large-scale prevention wall to prevent the inflow of seawater along the coast, or to create a freshwater body such as a reservoir near the coast to push out the inflow of seawater. This conventional technology has a structure that is developed for the functions of the embankment protection, the soil loss protection, the order, and the like, and thus it can be installed only by a large scale construction. Due to the limitations of the prior art, it is hardly applied in actual field, and successful results have not been obtained even in some applied cases. Particularly, the structure proposed in the prior art aims to block the horizontal movement of the contaminants in the soil. As described above, since the saline wedge rises, a blocking effect is exerted on a pattern in which the salt moves in the vertical direction There is a limit that can not be.

As another conventional technique, Korean Patent Laid-Open Publication No. 10-2018-0054995 proposes a method of pumping salt groundwater (seawater) by providing a water pipe below the interface between the groundwater and the salt groundwater. However, But it is not effective to prevent contamination of the groundwater well due to the rise of the wedge.

Korean Patent Publication No. 10-2018-0054995 (published May 25, 2018).

The present invention has been developed in order to overcome the limitations of the prior art as described above. It is an object of the present invention to provide a groundwater aquifer for groundwater utilization in coastal aquifers, The present invention aims to provide a technique capable of effectively preventing contamination of groundwater wells by effectively preventing movement in a vertical direction as well as in directions.

Particularly, in view of the fact that the salt contamination area in the soil due to the rise of the salt water wedge concentrates in a narrow area near the groundwater well, it is possible to easily and effectively prevent contamination of the groundwater well by only a small- The present invention also provides a technique for enabling a user to apply a measure that can be performed.

In order to achieve the above object, according to the present invention, there is provided an anti-salt structure for preventing groundwater contamination due to salt infiltration into a groundwater well, wherein both the upper and lower surfaces are open and the area of the lower surface is smaller than the area of the upper surface Shaped structure having a polygonal prism shape in the shape of a polygonal prism; Buried in the underground water layer above the interface between the underground and salt groundwater at the perforation site of the underground water well; And the salt is prevented from moving to the groundwater so that the salinity does not flow to the groundwater trough when the salinity is moved due to the rising phenomenon of the saline wedge.

According to another aspect of the present invention, there is provided a method of preventing salt infiltration into a groundwater well, the method comprising: disposing a ground at a predetermined depth to puncture the groundwater well; Forming a salinity-raising prevention structure according to the present invention and disposing it in a trench; A step of installing a water-shielding water-repellent film on the inner surface of the saline-rise preventing structure; And burying the saline-free structure and the aquifer into the ground by covering the space that has been eroded; And forming a bottom of the groundwater well so that the lower end of the groundwater well for amphibious water is located within the upper surface area of the salinity elevation preventing structure. do.

The saline infiltration barrier construction method of the present invention and the saline infiltration barrier construction method of the present invention can be formed by assembling a plurality of downward tapered assembly panels, The downward tapered type assembling panel is formed of a bent plate member having a trapezoidal frontal shape tapered downward so as to be narrowed in the transverse direction as it goes downward and having a curved plane of a U-shaped shape; At the laterally opposite lateral edges of the downwardly tapering assembly panel, there is formed an assembled end having a bite structure that is curled or interdigitated as shown in the figure so as to be connectable to neighboring downward tapered assembly panels ; The plurality of downwardly tapered assembly panels are continuously arranged in such a manner that the vertically adjacent downward tapered assembly panels and the U-shape are opposite to each other, and the assembly ends of the lateral edges are engaged while being slid vertically downward, And a lower surface of the polygon are formed into a truncated polygonal shape.

According to the present invention, in order to utilize the groundwater in the coastal aquifer, the underground water well is installed in the ground to pour the groundwater, and the saline water preventive structure is buried in the place where the groundwater well is formed, The path through which the salinity is moved is blocked or redirected by the salinity elevation preventive structure, and the salinity can be effectively prevented from flowing into the groundwater well and being contaminated.

In particular, according to the present invention, it is possible to easily construct a structure for preventing the rise of salinity by only a small-scale construction, not a large-scale construction. Therefore, the construction can be performed with low cost and time, There is an advantage that it can be used effectively.

In addition, in the present invention, since the installation of the salinity elevation preventive structure does not interfere with plant growth and surface infiltration of precipitation in the vegetation zone near the surface, the soil which has been excavated for the terra cotta is filled again, Is restored to an environment similar to that before the hydrogeologic survey, and the upper area of the salinity elevation structure can still maintain the groundwater aquifer capable of developing the groundwater well.

FIG. 1 is a schematic sectional view of a ground for explaining a saline wedge phenomenon occurring in a seawater aquifer.
Fig. 2 is a schematic cross-sectional view of the ground corresponding to Fig. 1 showing the rising phenomenon of the brine wedge;
FIG. 3 is a schematic diagram showing simulation results showing groundwater flow disturbance in a coastal aquifer due to groundwater development and rising of saltwater wedge. FIG.
4 is a schematic flow chart of a construction method according to the present invention.
FIG. 5 is a schematic cross-sectional view of a ground that schematically shows a state in which an anti-salt structure is installed around a groundwater well according to the present invention.
6 is a schematic perspective view of an anti-saline structure according to an embodiment of the present invention.
FIG. 7 is a schematic front view of the salinity increase prevention structure according to the present invention shown in FIG. 6. FIG.
8 is a schematic plan view and a schematic bottom view of an anti-salt build-up structure according to the present invention.
FIGS. 9 and 10 are schematic perspective views showing a downwardly tapered assembly panel in which directions for looking at an upward rising tilt-preventing structure according to the present invention are different. FIG.
11 is a schematic front view and a schematic rear view of a downward tapered assembly panel.
FIGS. 12 and 13 are schematic perspective views sequentially illustrating a process of assembling a downwardly tapered assembling panel to construct an anti-salt structure of the present invention.
FIG. 14 is a schematic cross-sectional view of a ground showing a state in which groundwater is pumped through a groundwater well in a state where an anti-salt structure according to the present invention is installed in the ground.

Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings. Although the present invention has been described with reference to the embodiments shown in the drawings, it is to be understood that the technical idea of the present invention and its essential structure and operation are not limited thereby.

FIG. 4 is a schematic flow chart of a construction method according to the present invention. FIG. 5 is a schematic view showing a state in which a salt rising prevention structure 100 according to the present invention is installed around a groundwater well 200 A schematic cross section is shown.

In the present invention, in order to prevent the salt water from moving in the horizontal direction and the vertical direction due to the rise of the salt water wedge to prevent the ground water well from being contaminated by salt, The saline ascending prevention structure 100 is disposed in advance, and then the groundwater well is pierced. Specifically, the ground is tapped at a predetermined depth at a predetermined puncturing site where the groundwater tunnel is to be drilled, thereby securing a space for assembling the salinity elevation preventing structure 100 (Step S1). Subsequently, the salt escape-preventing structure 100 according to the present invention having a structure to be described later is assembled and disposed in a tortuous installation space (step S2). When the arrangement of the salinity increase prevention structure 100 is completed, a watertight aeration tank is installed on the inner surface of the salinity increase prevention structure (step S3). Then, the salvage-preventing structure 100 and the aquifers are buried in the ground (Step S4). Finally, the ground water well 200 for the amniotic water is formed by vertically drilling the ground, so that the lower end of the groundwater well 200 is positioned within the range of the upper surface area of the salinity increase prevention structure 100 (step S5).

FIG. 6 is a schematic perspective view of an anti-saline structure 100 according to an embodiment of the present invention, and FIG. 7 is a schematic front view of the anti-saline structure 100 according to the present invention shown in FIG. Are shown. FIG. 8 is a schematic plan view and a bottom view showing the top and bottom surfaces of the anti-saline structure 100 according to the present invention shown in FIG. 6. FIG. 8 (a) , And Fig. 8 (b) shows the shape of the bottom surface. As illustrated in the drawing, the saline-free rise preventing structure 100 according to the present invention is a funnel-shaped assembly having a truncated cone shape in which both the top and bottom surfaces are open and the area of the bottom surface is smaller than the area of the top surface.

In the case of the embodiment illustrated in the figures, the salinity elevation preventing structure 100 is formed by assembling a plurality of downwardly tapering assembling panels 1. 9 and 10 are perspective views schematically showing different views of a downwardly tapered assembly panel 1 in which the salinity elevation preventing structure 100 according to the present invention shown in FIG. 6 is formed . Fig. 11 shows a schematic front view and a rear view of the downward tapered assembly panel 1. Fig. 11 (a) is a front view, and Fig. 11 (b) is a rear view. 12 and 13 are schematic perspective views showing a process of assembling the downward tapered assembly panel 1 to construct the anti-salt structure 100 according to the present invention shown in FIG. 6 .

The downwardly tapered assembly panel 1, which is to form the salt uplift preventing structure 100 by assembling, is formed of a trapezoidal plate material tapered downward so that the lateral width becomes narrower toward the bottom as shown in the front view of FIG. Particularly, in the embodiment shown in the drawings, the transversely opposite side edges of the downward tapered assembly panel 1 are annularly shaped as shown in the figure so as to be connected to neighboring downwardly tapered assembly panels, An assembling end portion 10 having a fitting structure is formed. In particular, in the embodiment shown in the drawings, the downwardly tapered assembly panel 1 is formed of a bent plate which is bent in a U-shape when viewed from above in order to improve rigidity. That is, the downwardly tapered assembly panel 1 is formed by the bent plate member having the bent planar shape of the U-shape.

The downward tapered assembly panel 1 having the above configuration is arranged such that the vertically adjacent downwardly tapered assembly panel and the U-shape are opposite to each other and is slid vertically downward to be inserted into the assembled end 10 of the transverse edge, Are coupled to each other. As shown in FIGS. 6 to 8, the downward tapered assembly panels 1 are sequentially arranged and adjacently arranged next to each other in the lateral direction in the above manner, so that the upper and lower surfaces are respectively formed of closed polygons, The salinity elevation preventing structure 100 is formed of a funnel-shaped polygonal prism assembly having a truncated cone shape with a lower surface and an upper surface and a lower surface both having an area smaller than that of the upper surface and penetrating in a vertical direction Is made. Of course, the shape of the anti-saline structure 100 according to the present invention is not limited to the polygonal prism, but may be a circular truncated cone having a top and a bottom in a circular shape, or an elliptical horn having an upper and a lower oval.

In the present invention, the salt rising prevention structure 100 having the above-described structure is installed in the ground at a predetermined puncturing site where the groundwater well will be drilled. At this time, as shown in FIG. 5, ) So that the salt elevation preventing structure (100) is positioned above the interface (B) between the groundwater and the salt groundwater. It is also possible to dispose the saline-free rise preventing structure 100 in a place where the saline-free rise preventing structure 100 is assembled and completed in advance by using the downwardly tapering type assembling panel 1, Type assembly panel 1 may be sequentially assembled and coupled so that the salinity increase prevention structure 100 is completely installed.

When the salinity elevation preventing structure 100 is installed, a catchment layer is installed on the inner side surface of the salinity elevation preventing structure 100 so that water can not permeate. After the aquifers are installed, the saline-free structure 100 and the aquifers are buried in the ground. In this state, the groundwater well 200 is vertically perforated on the ground. In this case, the lower end of the groundwater well 200 is positioned within the range of the upper surface area of the salinity increase prevention structure 100. That is, the groundwater well 200 is positioned within the range of the upper surface area of the salinity elevation preventive structure 100 when viewed from a flat surface.

FIG. 14 is a schematic cross-sectional view of a ground in a state following FIG. 5 showing a state in which groundwater is pumped through a groundwater well 200 in a state where the saline- Are shown. When the salinity elevation preventing structure 100 is installed and the groundwater well 200 is formed by the construction method of the present invention as described above, when the groundwater is pumped into the groundwater well 200, The underground groundwater is collected and pumped into the groundwater well 200 from the underground groundwater layer above the installed height. At this time, the ascending path is blocked by the saline ascending prevention structure 100 due to the rise of the saline wedge, and the saline descending structure 100 flows in the sea water direction along the tapered outer surface of the saline descending prevention structure 100, The underground sewer pumped into the groundwater canal 200 does not enter or the amount of the inflow is very slight.

As mentioned earlier, the path of salinity shifts due to the rising of the saline wedge due to the pumping water in the groundwater becomes a form to gather at the point where the groundwater is pumped. As a result, And is limited to areas near the groundwater reservoir. In the present invention, as described above, since the taper-shaped saline ascending / descending structure 100, which is narrowed in the downward direction toward the lower side of the groundwater well 200 toward the lower side of the groundwater well 200, is buried in the ground, The path of the salinity shifts due to the rise of the saline wedge occurring in the process is turned off toward the saltwater underground layer while being blocked by the salinity preventive structure 100. Therefore, the inflow of the salinity to the groundwater well is minimized or minimized to a minimum, thereby effectively preventing contamination of the saline groundwater.

Particularly, in the present invention, since the salinity elevation preventive structure 100 has a truncated cone shape with its section becoming narrower as it goes downward, it is possible to effectively prevent the salinity wedge from being shifted and the penetration into the groundwater well But it does not disturb the whole flow of salt groundwater and groundwater in coastal aquifers. The salinity elevation preventing structure 100 according to the present invention has the advantage that the area occupied in the ground is small owing to the shape as described above, and thus the flow of the groundwater is not obstructed besides the suppression of the rising phenomenon of the brine wedge.

In addition, in the present invention, since the salt rising prevention structure 100 is formed by assembling a downward tapered type assembling panel 1 in the form of a plate, a flat surface exists on the inner side surface thereof. Therefore, ), And it is advantageous that the order performance by the sub-film can be exhibited very effectively through this.

Furthermore, in the present invention, based on the fact that the area where the salinity is introduced into the soil and is contaminated is limited to the area near the groundwater well, only the local area around the expected location for installing the groundwater well is excavated, It is possible to reduce the construction amount of the trowel and the like, and thus the construction is simplified, the construction cost is short and the construction time is short, so the workability is very excellent, . Further, in the present invention, since the salinity increase prevention structure 100 is installed in a depth region within a few meters below the surface of the ground, there is an advantage that it does not interfere with vegetation growth in the vicinity of the surface and infiltration of the surface by precipitation, Since the soil that has been excavated for the terra cotta is re-filled after the soil is installed in the ground, all the spaces except the volume of the salt elevation preventive structure 100 itself are restored to a hydrological similar environment before the construction. Thus, the upper region of the saline-free structure 100 can still maintain a groundwater aquifer capable of developing a groundwater well.

As described above, in the present invention, unlike the prior art in which a large-scale barrier wall for blocking seawater intrusion is cut off, only the anticipated movement path of salt due to the rise of the brine wedge of a few meters in size is blocked and converted, It can be very useful for the development of groundwater reservoir for small scale, sporadically scattered facility cultivated land near the coast.

1: Downward tapered mounting panel
100: Structure to prevent salt build-up
200: groundwater observation

Claims (5)

As an anti-salt structure to prevent contamination of groundwater due to salt infiltration into groundwater,
The salinity elevation preventing structure is formed by assembling a plurality of downward tapered assembling panels made of a sheet material having a trapezoidal front face tapered downward so that the lateral width becomes narrower toward the bottom,
Wherein the transversely opposite side edges of the downwardly tapered assembly panel are formed with an assembled end having an engaging structure engageable with or interlocking with each other so as to be connected to neighboring downward tapered assembly panels;
A plurality of downwardly tapered assembly panels are continuously arranged in such a manner that the transversely adjacent downwardly tapering assembling panels and the U-shape are opposite to each other, and the assembly ends of the lateral edges are engaged with each other while being slid vertically downward, The polygonal truncated cone is formed in a polygonal truncated cone shape having a lower surface area smaller than an upper surface area, the upper surface and the lower surface being both open and closed, respectively;
The salinity elevation preventing structure is buried in the underground water layer above the interface between the underground groundwater and the salt groundwater at the perforation position of the underground water well and is positioned in the saline flow path when the salinity moves due to the rise of the saline wedge, Wherein the salt is prevented from flowing so as not to flow toward the groundwater well.
delete delete The method according to claim 1,
Wherein an anti-saline structure is provided on the inner surface of the structure for preventing rising of salinity.
As a construction method to block salt infiltration into a groundwater well,
Disposing the ground at a predetermined depth to puncture the groundwater well;
Forming an anti-saline structure according to claim 1 on the ground;
A step of installing a water-shielding water-repellent film on the inner surface of the saline-rise preventing structure; And
Burying the salvage-preventing structure and the aquifers into the ground; And
And forming a groundwater well by vertically drilling the groundwater well so that the lower end of the groundwater well for amphibious water is located within a range of the upper surface area of the salinity elevation preventing structure.

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