JPH07259144A - Ground water collecting method and cleaning method of under-ground pit - Google Patents

Abstract

PURPOSE:To collect water at a low cost by supplying pressure air to a second pipe line from the ground, and blowing off ground water flowing into a first pipe line to pump up water to the ground side. CONSTITUTION:An air valve is opened to supply compressed air to the inside of a pipe 5 from a compressor 6 through an air hose 9. Ground water in the pipe 5 is raised up so that it is blown off as a mass of water, and in the case air breaks the mass, the air is only lifted, and the ground water falls down. Then, the falling ground water is blown off by the compressed air supplied in succession, and is lifted again. In the case such a state is repeated several times, the volume of the ground water 4 blown off is gradually increased. When the ground water 4 to be blown off reaches a certain amount, it is pushed up to the ground through the pipe 5 and is moved to the inside of a water taking tank 7 through a connection pipe 10.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for collecting groundwater in an underground pit for collecting groundwater at each depth in an underground pit, examining the water quality, and investigating the location of a contaminated layer. The present invention relates to a method for cleaning the inside of an underground pit for utilizing the underground pit.

[0002]

2. Description of the Related Art Conventionally, when collecting groundwater at an arbitrary depth in an underground pit, after drilling a vertical hole such as a boring hole or a well to the target depth, a pump is installed at the bottom position, The groundwater that springed in the pit was sucked by this pump and pumped to the ground by a pump pipe attached to the pump to collect water. Also, in the case of collecting groundwater at a deeper place in this pit, after pulling up the pump, re-excavating the pit, installing the pump again at the bottom position of the pit, and collecting water in the same manner as above. Was. By the way, in order to install the pump in the vertical hole, the pump and the pumping pipe attached to the pump were hung by a crane, and these were raised and lowered. In addition, when the pump is moved within one vertical hole and water is sampled from several locations for water quality inspection, the initial water sampling of the pump is drained to a predetermined location on the ground and discarded, and then water sampling is performed. The water quality of the groundwater at the pump position (groundwater at the target water level) was checked. The reason for discarding the sampled water at the beginning of the movement of the pump is that the groundwater pumped before the movement of the pump remains in the pumping pipe, and this residual groundwater contains water that is not the groundwater of the desired depth.

On the other hand, the vertical hole excavated as described above is
It may be used for various purposes such as wells. When using this pit, it is necessary to wash the wall surface in the pit and clean the groundwater in the pit. Conventionally, as a method for cleaning the wall surface in the pit and cleaning the groundwater in the pit, by pumping the groundwater to the ground using a pump, as in the groundwater sampling method in the pit described above, The water flow that occurred on the surface of the pit removed the contaminants such as muddy water film adhering to the wall surface of the pit and sucked it into the pump together with the groundwater to pump it to the ground.

[0004]

However, in the above-mentioned groundwater sampling method, there is a problem that the pumping pipe is largely installed when the pump is moved, resulting in poor work efficiency. In addition, when the pump is moved in one vertical hole and water is collected from several positions, the above-mentioned groundwater before pump movement remains in the pumping pipe or excessive pumping occurs, so the target depth is There is a problem that it is not possible to accurately pump only the groundwater at the position, and it is difficult to judge whether the sampled groundwater is at the desired target depth position, and the flow of groundwater in the pit. There was also a problem that it often disturbed. In addition, when using this method, if the hole diameter of the vertical hole is particularly small, the size of the pump is larger than this hole diameter and there is no suitable pump that can be installed. When the target depth is particularly deep, there was no corresponding pump because the pump head used was too small for this depth, and as a result there was a problem that the range of water sampling was limited.

Further, in order to install the pump at a predetermined depth position in the vertical hole and collect water, the pump and the pumping pipe attached to this pump were hung by a crane, and they were raised and lowered. As described above, there is a problem that it is difficult to support the pumping pipe in addition to the large scale of the device. In addition, there is a problem that it is troublesome to collect water on the ground when draining residual ground water to a predetermined place on the ground and discarding it, and then collecting the groundwater at the pump position for water quality inspection.

Further, when the wall surface in the pit is cleaned and the ground water in the pit is cleaned, the water level of the ground water in the pit drops, so that the muddy water attached to the inner wall surface of the pit above the pump position is lowered. There is a problem that it is difficult to remove contaminants such as membranes, and in order to clean the inner wall surface of the vertical hole above the pump position, the pump and pump pipe position must be moved upward. Since the installation is large, there is a problem that it requires a great deal of labor, the work efficiency is poor, and it is difficult to support the pumping pipe.

The present invention has been made in view of the above circumstances, and can collect groundwater at any position in a pit without using a special device, does not disturb the groundwater flow field in the pit, and is inexpensive. It is an object of the present invention to provide a groundwater sampling method and a cleaning method in an underground pit capable of sampling water.

[0008]

The invention according to claim 1 is
In order to achieve the above object, a first pipeline and a second pipeline are provided from the ground in a vertical hole formed by excavating the ground, and the second pipeline is provided in a lower end opening of the first pipeline. With the tip end of the pipeline inserted, the lower end opening of the first pipeline is located at a predetermined depth in the groundwater that has sprung into the vertical hole. Pressurized air is sent to the pipeline, and groundwater flowing into the first pipeline from the lower end opening thereof is blown off by the pressurized air ejected from the tip of the second pipeline to the ground side. It is configured to pump water. Further, in order to achieve the above-mentioned object, the invention according to claim 2 is the same as the invention according to claim 1,
The conduit is a flexible air supply hose. In order to achieve the above-mentioned object, the invention according to claim 3 is the invention according to claim 2, wherein a flexible water sampling hose is connected to the upper end of the first pipeline, and the vertical hole on the ground is connected. Is provided around the periphery of the water sampling hose, and the water sampling hose is attached to the first hose with the water sampling hose being locked to the locking body.
Is suspended, and the depth position of the lower end opening of the first pipeline is changed by changing the locking position of the water sampling hose to the locking body. ing.
Further, in order to achieve the above-mentioned object, the invention according to claim 4 is the invention according to claim 3, wherein a water reservoir is provided on a water sampling outlet side of the water sampling hose, and a lower end opening of the first pipeline is provided. Is located at the groundwater sampling depth, the groundwater in the first pipeline is introduced into the water reservoir and is drained, and then the groundwater flowing into the first pipeline is further treated as described above. It is configured to be introduced into a water reservoir and used as groundwater for sampling. In order to achieve the above-mentioned object, the invention according to claim 5 is the invention according to claim 1, wherein both the first conduit and the second conduit are flexible hoses. While pumping groundwater, the wall surface in the vertical hole is washed and the groundwater is cleaned.

[0009]

According to the structure of claim 1 or 2, the groundwater is sampled only from the lower end of the first pipeline in the pit, so that the groundwater flow field in the pit is not disturbed. Accurately sample groundwater at the target depth, widen the range of water that can be sampled, and clarify the depth of groundwater layer contaminated by water quality inspection of water sampling at any depth. In addition, according to the configuration of claim 3, the lower end of the first pipeline is changed by changing the locking position of the water sampling hose to the locking body in addition to the operation of the first or second aspect. Water is collected at an arbitrary target depth, thereby eliminating the need for a heavy machine such as a crane for suspending the hose, making it easy to move the water sampling hose, and improving the operability of moving the first pipeline. . Further, according to the configuration of claim 4, in addition to the function of claim 1, claim 2, or claim 3, the unnecessary collection water is introduced into the water reservoir container and is drained, whereby the unnecessary collection is performed. The drainage of water is made extremely easy, and the drainage of waste water and the exchange work for the required depth of interest are swiftly and easily performed, and the water of the required depth is promptly taken. Further, according to the configuration of claim 5, in addition to the function of claim 1,
Due to the flow of groundwater that moves toward the lower end of the hose near the lower end of the hose, contaminants such as muddy water film attached to the inner wall surface of the vertical hole at the depth position of the lower end of the hose are peeled off. Then, the separated contaminants are sucked into the hose from the lower end of the hose together with the groundwater and carried to the ground, thereby cleaning the inner wall surface part of the vertical hole at the depth position of the lower end of the hose and at the depth position of the lower end of the hose in the vertical hole. Cleans groundwater. In addition, the hose is sequentially moved in the vertical direction, and at each target depth, groundwater in the hose is pumped to wash the entire inner wall surface below the water surface of the pit and also to clean all the groundwater in the pit.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will be described below with reference to FIGS.
It will be described based on. FIG. 1 is a schematic vertical cross-sectional view of a water sampling device 1 showing a situation in which the method for sampling groundwater in an underground pit according to the present invention is applied to sampling groundwater in a borehole,
In FIG. 1, reference numeral 2 is a boring hole (vertical hole) formed in the ground 3. Groundwater 4 is stored in the boring hole 2, and a lower end portion of a pipe 5 (first pipe line) made of vinyl chloride is vertically inserted into the groundwater 4. The symbol ▽ shown in FIG. 1 indicates the water surface S, and the symbol H
Indicates that the depth of the lower end of the pipe 5 from the water surface S is H.

A compressor 6 is installed at a predetermined location near the edge of the boring hole 2 on the ground 3, and a water sampling tank 7 is provided at another predetermined location near the edge of the boring hole 2 on the ground 3. ing. An air supply valve 8 is attached to the discharge port of the compressor 6, and one end of a flexible air supply hose 9 (second pipe line) is attached to the air supply valve 8. The other end of the air supply hose 9 is inserted upward into the lower end of the pipe 5 in the boring hole 2.
One end of a communication pipe 10 (first pipe line) is communicated with the upper end of the pipe 5, and the other end of the communication pipe 10 is the water sampling tank 7.
Is exposed to the upper part of. The pipe 5 and the communication pipe 10 form a first conduit. At the lower end of the pipe 5, the compressor 6 can supply an air supply pressure equal to or higher than the water pressure in the pipe 5 below the water surface S (air supply pressure equal to or higher than the water pressure in the pipe 5 at the water level H shown in FIG. 1). Has been done. The inner diameter of the pipe 5 is the compressor 6
The inner diameter of the air supply hose 9 attached to the air supply valve 8 is about 2 to 3 times.

Next, the method for collecting groundwater in the underground pit according to the present invention will be described together with the operation of the water sampling device 1.
FIG. 1 schematically shows a situation in which the groundwater 4 in the pipe 5 rises from the initial state when the groundwater 4 is pumped. In FIGS. 1 to 4, the bubble-like display indicates that there is no water and only air continuously flows, and the broken line indicates a place where water exists.

First, when the pipe 5 is inserted into the groundwater 4, the groundwater 4 having the same water level as the water surface S (the same height as the water surface S) is flowing into the pipe 5. First, as shown in FIG. 1, the air supply valve 8 is opened and compressed air is supplied from the compressor 6 into the pipe 5. In this case, the air pressure of the air sent from the compressor 6 is set so that the air pressure at the lower end of the pipe 5 is equal to or higher than the water pressure in the pipe 5 below the water surface S shown in FIG. Then, the groundwater 4 in the pipe 5 rises so as to be ejected as a lump, and when the air breaks the lump, only the air rises and the groundwater 4 falls. This groundwater 4
Drops to a position above the initial state, is blown by the compressed air that is continuously supplied, and rises again. By repeating this state several times, the amount of groundwater 4 that is thrown away gradually increases, and when this amount reaches a certain amount, it is pushed up to the ground via the pipe 5 and passes through the communication pipe 10 to collect water as shown in FIG. Move into the tank 7.

At this time, since the groundwater 4 in the pipe 5 is pumped up, a pressure drop of the groundwater 4 near the lower end of the pipe 5 occurs. Groundwater 4, that is, the groundwater 4 at the depth H position shown in FIG. 1 flows in. At this time, the pumping state is continued as it is, and at least the pipe 5 and the communication pipe 10 which are initially stored in the water sampling tank 7 are discarded, and the groundwater 4 corresponding to the amount of water in the first pipeline is discarded. The pumped water is stored in the water sampling tank 7. Next, required processing such as water quality inspection of the water in the water sampling tank 7 is separately performed. The groundwater 4 first collected in the water sampling tank 7 is discarded because the groundwater 4 initially collected in the water sampling tank 7 is the water containing the groundwater 4 in the pipe 5 at a portion shallower than the depth H shown in FIG. This is because it is not only the groundwater 4 of the depth H that is the target for the water quality inspection. Here, as described above, when the compressed air is supplied from the air supply hose 9 to the lower end opening of the pipe 5 to pump the groundwater in the pipe 5 onto the ground 3,
If the cross-sectional areas of the air supply hose 9 and the pipe 5 are about the same,
The groundwater in the pipe 5 is pumped out as if it is pushed out, but there is a problem that the pressure of the compressed air is great due to the large resistance of the inner wall of the pipe 5, and the amount of groundwater flowing into the pipe 5 is too small. Occurs. On the contrary, when the cross-sectional area of the pipe 5 is considerably larger than the cross-sectional area of the air supply hose 9, the ground water blown by the compressed air drops to the initial position before being blown, and only the compressed air is discharged. There is a problem that the pipe 5 is pushed up and extruded, and it is almost impossible to pump water. Therefore, as described above, the inner diameter of the pipe 5 is about 2-3 times the inner diameter of the air supply hose 9 attached to the air supply valve 8 of the compressor 6.

Next, the air feeding valve 8 of the compressor 6
Closed, and when the pipe 5 is inserted into the boring hole 2 at the upper end of the pipe 5, the lower end of the pipe 5 reaches another arbitrary depth position where water is desired to be collected.
The (first pipe line) is added and vertically inserted into the boring hole 2 as shown in FIG. At this time, as shown in FIG. 3, the groundwater 4 flows into the pipes 5 and 11 at the same water level as the water surface S (at the same height as the water surface S). Further, in this case, the pipe 5, the pipe 11 and the communication pipe 10 form a first pipeline. The inner diameter of the pipe 11 is the same as the inner diameter of the pipe 5.

Next, the air supply valve 8 is opened and air is supplied from the compressor 6 into the pipes 5 and 11. In this case, the air pressure of the air sent from the compressor 6 is
At the lower end of the pipe 5,1 below the water surface S shown in FIG.
Air is supplied so that the air pressure is equal to or higher than the water pressure in 1. Then, the groundwater 4 in the pipes 5 and 11 is, as described above,
It is blown up by the compressed air that is continuously supplied, lifted and pumped, passes through the communication pipe 10, and as shown in FIG.
Move in.

At this time, since the water in the pipes 5, 11 is pumped up, the pressure of the groundwater 4 near the lower end of the pipe 5 drops, so that the pipe 5,
The groundwater 4 around the lower end of the pipe 5, that is, the groundwater 4 at the depth H position shown in FIG.

Further, at this time, the pumping state is continued as it is, and at least an amount of water which is initially stored in the water sampling tank 7 and corresponds to the amount of water in the pipes 5 and 11 and the communication pipe 10, that is, the first pipe line is not. After discarding, the pumped water after that is collected in the water sampling tank 7. Next, required processing such as water quality inspection of the water in the water sampling tank 7 is separately performed. This first water sampling tank 7
The groundwater 4 accumulated inside is discarded because it is the water containing the groundwater 4 in the pipes 5 and 11 in the portion shallower than the depth H shown in FIG. This is because it is not the only groundwater 4 to be inspected.

Further, when it is desired to collect the groundwater 4 at a deep position in the borehole 2, the air supply valve 8 is closed and the pipe is inserted into the borehole 2 as described above. Add another pipe (not shown) having a length that the lower end of the pipe reaches an arbitrary depth position to be sampled (this pipe becomes a part of the first pipeline) to the upper end of the pipe 11. , These pipes 5, 1
1, another pipe (not shown) and an air supply hose 9 are vertically inserted into the boring hole 2 with the lower end of the pipe 5 positioned downward. At this time, the groundwater 4 enters into the pipes 5, 11 and another pipe (not shown) connected to the pipe 11 as in the state shown in FIG. Next, the air supply valve 8 is opened, and the pipe 5 and the pipe 1 from the compressor 6 are opened.
1. Air is fed into another pipe (not shown) connected to the pipe 11.

In this case, the air pressure of the air sent from the compressor 6 is equal to or higher than the water pressure in the pipes 5 and 11 below the water surface S and another pipe (not shown) connected to the pipe 11 at the lower end of the pipe 5. And send air. As a result, as described above, the ground water 4 in the pipes 5, 11 and another pipe (not shown) connected to the pipe 11 is blown up by the continuously supplied compressed air to be pumped up, and the communication pipe 10 is connected. To move into the water sampling tank 7.

At this time, the water in another pipe (not shown) connected to the pipes 5, 11 and the pipe 11 is pumped up, so that the pressure of the groundwater 4 near the lower end of the pipe 5 is reduced. Groundwater 4 around the lower end of this pipe from the lower end of this pipe, pipe 11 and pipe 1
It flows into another pipe (not shown) that is added to 1.

Further, at this time, the pumping state is continued as it is, and at least the pipes 5, 11 initially stored in the water sampling tank 7 and another pipe (not shown) connected to the pipe 11 and the amount of water in the communication pipe 10 are set. Discard the equivalent amount of water,
The pumped water thereafter is stored in the water sampling tank 7. Next, required processing such as water quality inspection of the water in the water sampling tank 7 is separately performed. The groundwater 4 first accumulated in the water sampling tank 7 is discarded because the groundwater 4 first accumulated in the water sampling tank 7 is discarded.
Is water including the groundwater 4 in the pipe in a portion shallower than the depth of the lower end of the pipe 5, and is not the target groundwater 4 for water quality inspection.

Further, when it is desired to collect the groundwater 4 at an arbitrary deep position in the boring hole 2, the groundwater 4 at the arbitrary position can be collected by repeating the same means as described above.

As shown in FIG. 4, the length from the water surface S of the groundwater 4 to the lower end of the pipe 5 is H, the length from the ground surface to the lower end of the pipe 5 is L, and the inner diameter of the air supply hose 9 is 10
mm, the inner diameter of the pipe 5 is 25 mm, that is, the inner diameter ratio between the air supply hose 9 and the pipe 5 is 1: 2.5 (cross-sectional area ratio 1:
In the case of 6), it has been confirmed by carrying out that the groundwater 4 in the pipes 5 and 11 can be pumped to the ground in a state where the length is about L ≦ 4H.

As described above, according to the method described in the first embodiment, the pipes 5, 11, ..., The compressor 6, the water sampling tank 7, the air supply hose 9, and the communication pipe 10 are simply installed. With a simple device, the groundwater 4 at an arbitrary water level in the borehole 2 can be easily and inexpensively collected as compared with the conventional method. Moreover, since the groundwater 4 is sampled only from the lower end of the lowermost pipe in the boring hole 2,
The flow of groundwater 4 in the boring hole 2 is quiet, and the groundwater 4 flow field is not disturbed, and groundwater of any target depth can be accurately sampled. Further, even if the target depth to be sampled is deep, it is only necessary to add the pipes as described above, so that the range of sampled water can be made wider than in the conventional case. In addition, as described above, it is possible to find out at what depth the groundwater layer is contaminated by inspecting the water quality of the water sample at any depth, which is very effective in use.

Next, a second embodiment of the present invention will be described with reference to FIGS. In this embodiment, the same parts as those in the first embodiment are designated by the same reference numerals and detailed description thereof will be omitted. FIG. 5 is a schematic vertical cross-sectional view of a water sampling device 21 showing a state in which the method for sampling groundwater in an underground shaft according to the present invention is applied to sampling groundwater in a boring hole 2. Reference numeral 22 denotes a transparent flexible pressure-resistant hose (water sampling hose) which has one end sealed and connected to the upper end of the pipe 5 so as to communicate with the inside of the pipe 5 (first conduit).
Is. The other end of the pressure-resistant hose 22 is communicated with one side portion of the upper part of the water storage container 23 installed above the water collection tank 7. Then, the pipe 5 and the pressure-resistant hose 22 form a first pipeline.

A water collecting port 24 is provided at the bottom of the water collecting container 23 so that the water in the water collecting container 23 can pass through the water collecting tank 7. The water collecting port 24 is provided with a water collecting valve 25. The water outlet 24 is provided so as to be openable and closable. Further, a tank 26 is installed on the ground 3 adjacent to the water sampling tank 7 and the water reservoir 23. One end of an exhaust pipe 27 communicates with the other side of the upper part of the water reservoir 23, and the other end of the exhaust pipe 27 faces the upper part of the tank 26. The pressure-resistant hose 22 is appropriately rounded and hooked on a stake 28 (locking body) (shown by an imaginary line in FIGS. 5 to 9) provided near the hole edge of the boring hole 2.

The compressor 6 is designed to be capable of supplying the compressed air pressure at the lower end of the pipe 5 above the water surface S and above the water pressure inside the pipe 5. Further, the inner diameter of the pipe 5 is equal to that of the air supply hose 9 (second
It is the same as in the first embodiment that the inner diameter of the pipe line is about 2 to 3 times.

Next, the method of sampling groundwater in the underground pit according to the present invention will be described together with the operation of the water sampling device 21. FIG. 5 schematically shows a situation in which the groundwater in the pipe 5 rises from the initial state when the groundwater 4 is pumped. Initially, when the pipe 5 is inserted into the groundwater 4, the groundwater 4 having the same water level as the water surface S (the same height as the water surface S) is flowing into the pipe 5. First, as shown in FIG. 5, the water sampling valve 25 is closed,
Air is fed into the pipe 5 from the compressor 6. In this case, the air pressure sent from the compressor 6 is lower than the water level S of the ground pipe 5 at the lower end of the pipe 5.
Air is supplied so that the air pressure is higher than the water pressure inside.

Then, as described above, the groundwater 4 in the pipe 5 and the pressure-resistant hose 22 is blown up by the continuously supplied compressed air and is pumped up. It moves into the water reservoir 23 as shown. At this time, the groundwater 4 in the pipe 5 is pumped, so that the pressure of the groundwater 4 near the lower end of the pipe 5 is reduced, and the groundwater 4 near the lower end of the pipe 5, that is, the groundwater 4 near the lower end of the pipe 5, The groundwater 4 at the depth H position shown in FIG. 5 flows in. When the groundwater 4 reaches the water storage container 23 as described above, the water collection valve 25 is opened to allow the groundwater 4 in the water storage container 23 to flow into the water collection tank 7. At this time, at least an amount of water corresponding to the amount of water in the pipe 5 and the pressure-resistant hose 22 accumulated in the water sampling tank 7 is discarded, the water sampling valve 25 is closed, and the subsequent pumping water is again stored in the water storage container 23 and again. The water sampling valve 25 is opened, and the groundwater 4 in the water storage container 23 is caused to flow into the water sampling tank 7 to be the groundwater to be sampled. Then, the water quality of the groundwater 4 in the water sampling tank 7 is inspected.

Next, the water sampling valve 25 is closed, and as shown in FIG. 7, the lower end of the pipe 5 is positioned at an arbitrary depth at which water is to be sampled by changing the locking position of the pressure resistant hose 22 to the pile 28 described later. So that the pressure-resistant hose 22 is lowered. When the lower end of the pipe 5 reaches an arbitrary depth for collecting water, as shown in FIG. 8, after the groundwater 4 reaches the water reservoir 23, as shown in FIG. The water inside is flowed into the water sampling tank 7 to sample water. In this water sampling, at least an amount of groundwater 4 accumulated in the water sampling tank 7 corresponding to the amount of water in the pipe 5 and the pressure resistant hose 22 is discarded. After that, the water sampling valve 25 is closed, and after the groundwater 4 reaches the water storage container 23, the water sampling valve 25 is opened to allow the water in the water storage container 23 to flow into the water sampling tank 7, which is used as the groundwater to be sampled. Collect water. Next, the water in the water sampling tank 7 is sampled and a required treatment such as water quality inspection is separately performed.

Further, when it is desired to sample the groundwater 4 at a deep position in the boring hole 2, the water sampling valve 25 is closed,
The above means are repeated. If the pressure-resistant hose 22 is somewhat rigid, the pipe 5 is omitted and the pressure-resistant hose 22 is
The lower end of the air supply hose 9 is inserted into the tip of the air supply hose 9, and the end of the pressure resistant hose 22 into which the air supply hose 9 is inserted is directly inserted into the boring hole
It may be inserted vertically inside. The pressure hose 22
Since it is hung on a locking body for hose hooking such as a pile 28 provided near the boring hole 2, it is movable and can be easily supported.

As described above, according to the groundwater sampling method in the underground pit described in the second embodiment, it is not necessary to use a special device, and the pipe 5, the compressor 6, the sampling tank 7, and the feeding tank are provided. With a simple device that only installs the air hose 9, the water reservoir 23, and the tank 26, the groundwater 4 at an arbitrary depth position in the boring hole 2 can be easily and inexpensively collected as compared with the conventional method. . In addition, since the groundwater 4 is pumped only from the lower end of the pipe 5, the flow of groundwater in the borehole 2 is quiet and does not disturb the groundwater flow field, and groundwater of any target depth can be accurately sampled. You can Further, even if the target depth to be sampled is deep, it is sufficient to lower the pipe, so that the range of sampled water can be made wider than in the conventional case. Further, as described above, it is possible to find out at what depth the groundwater layer is contaminated by conducting a water quality inspection of the water at any depth.

Further, in the second embodiment, it is not necessary to use a heavy machine such as a crane for suspending the hose, and a pile 28 or the like for hanging the pressure resistant hose 22 near the well or the vertical hole such as the boring hole 2 is required. Since there is a locking body, the operability of the hose is good, and the pressure-resistant hoses can be rolled into a bundle so that they can be carried easily without taking up space. Also, the water reservoir 2
Introducing waste water that is not the groundwater of the target water level remaining in the pipe 5 and pressure-resistant hose 22 into 3 and drains this waste water makes it possible to drain this waste water very easily. It is possible to promptly and easily carry out the work of exchanging water with the water of the required depth of interest, and to promptly and easily take the water of the required depth of interest, thereby improving the work efficiency.

Next, a third embodiment of the present invention will be described with reference to FIGS. In the third embodiment, the same parts as those in the first embodiment are designated by the same reference numerals, and detailed description thereof will be omitted. FIG. 10 is a schematic vertical cross-sectional view of the cleaning device 31 showing a situation in which the method for cleaning the inside of the underground pit according to the present invention is applied to the cleaning of the inner wall surface of the boring hole 2 and the cleaning of groundwater in the boring hole 2. is there. In FIG. 10, reference numeral 32 is a transparent flexible pressure-resistant hose (first conduit) having one end vertically inserted into the boring hole 2. The other end of the pressure resistant hose 32 is inserted from above into a side groove 33 formed in the ground 3 in the vicinity of the boring hole 2 so as to be separated from the boring hole 2. As with the first embodiment, the tip of the air supply hose 9 (second pipe line) is inserted upward at one end of the pressure-resistant hose 32.

At the lower end of the pressure-resistant hose 32, the compressor 6 can supply compressed air pressure higher than the water pressure in the pressure-resistant hose 32 below the water surface S. Further, the inner diameter of the pressure-resistant hose 32 is about twice the inner diameter of the air supply hose 9 attached to the air supply valve 8, as in the first embodiment.

Next, the method of cleaning the inside of the underground pit according to the present invention will be described together with the operation of the cleaning device 31. Figure 1
0 represents a simulated situation in which the groundwater in the pressure-resistant hose 32 rises from the initial state when the groundwater 4 is pumped up and the inner wall of the boring hole 2 is washed. In FIG. 10 and FIG. 11, a bubble-like display indicates that there is no water and only air continuously flows, and a broken line indicates a place where water exists.

First, when the pressure-resistant hose 32 is inserted into the groundwater 4, the groundwater 4 having the same water level as the water surface S (the same height as the water surface S) has flowed into the pressure-resistant hose 32. First, as shown in FIG. 10, the air supply valve 8 is opened and air is supplied from the compressor 6 into the pressure-resistant hose 32. In this case, the air pressure of the air sent from the compressor 6 is set so that the air pressure at the lower end of the pressure-resistant hose 32 is equal to or higher than the water pressure in the pressure-resistant hose 32 having the water surface S or lower shown in FIG. Then, the groundwater inside the pressure-resistant hose 32 is blown up by the continuously supplied compressed air and pumped up, as described above.
It moves through the pressure-resistant hose 32 toward the side groove 33 as shown in FIG.

At this time, the groundwater 4 in the pressure-resistant hose 32 is pumped up, so that the pressure of the groundwater 4 near the lower end of the pressure-resistant hose 32 is lowered, and the pressure-resistant hose 32 enters the pressure-resistant hose 32 from the lower end of the pressure-resistant hose 32. The groundwater 4 around the lower end, that is, the groundwater 4 at the depth position (the depth H position shown in FIG. 10) at the lower end of the pressure-resistant hose 32 flows in. Then, near the lower end of the pressure-resistant hose 32, a flow of the groundwater 4 moving toward the lower end of the pressure-resistant hose 32 is generated, which causes the inner wall surface of the bore hole 2 at the depth position of the lower end of the pressure-resistant hose 32 to the inner wall surface portion. Contamination such as muddy water film that has adhered to the surface will peel off. The separated contaminants are sucked into the pressure-resistant hose 32 from the lower end of the pressure-resistant hose 32 together with the groundwater 4, move to the ground, and are carried to the gutter 33. Therefore, the inner wall surface portion of the boring hole 2 at the depth position at the lower end of the pressure resistant hose 32 is washed, and the groundwater 4 at the depth position at the lower end of the pressure resistant hose 32 in the boring hole 2 is cleaned. This groundwater pumping state is continued immediately below the water surface S of the groundwater 4 in the borehole 2 until the groundwater 4 in the borehole 2 becomes clean. As a result, the muddy water in the boring hole 2 is also drained.

Next, as shown in FIG. 11, the pressure-resistant hose 32 is moved downward sequentially by changing the locking position of the pressure-resistant hose 32 to the pile 28, and the groundwater 4 in the boring hole 2 is removed at each target depth. The pumping state is continued immediately below the water surface S of the groundwater 4 in the borehole 2 until the groundwater 4 in the borehole 2 is clean. As a result, the entire inner wall surface below the water surface in the boring hole 2 is cleaned, and all the groundwater 4 in the boring hole 2 is cleaned. In addition,
Here, instead of sequentially moving the pressure-resistant hose 32 downward in the boring hole 2, the pressure-resistant hose 32 may be sequentially moved in the boring hole 2 from the lower side to the upper side. By the way, from the test results, when the outer diameter of the transparent pressure-resistant hose is 33 mm (inner diameter 25 mm) and the outer diameter of the air supply hose is 16 mm (inner diameter 10 mm),
The relationship between the length of the transparent pressure-resistant hose below the water table and the amount of pumped water is shown in Table 1 and FIG. As you can see from these figures,
For example, when the water table is 26 m below the ground surface and the length of the transparent pressure-resistant hose below the water table is 13 m, the pumping rate is 13.1 l / min due to the resistance of the inner wall of the transparent pressure-resistant hose.

[0041]

[Table 1]

As described above, according to the method for cleaning the inside of the underground vertical hole described in the third embodiment, it is not necessary to use a special device, and the compressor 6, the air supply hose 9, the pressure resistant hose 32, and the side groove are not required. With a simple device that only installs 33, the inner wall of the boring hole 2 can be easily and inexpensively cleaned compared to the conventional method using a pump, and all the groundwater in the boring hole 2 can be easily cleaned. can do. Further, a heavy machine such as a crane for suspending the pressure-resistant hose 32 is not required, and there is a locking body such as a pile 28 for hanging the pressure-resistant hose 32 near the vertical hole such as the boring hole 2 so that the pressure-resistant hose 32 can be easily used. Since the pressure-resistant hose 32 has flexibility, the operability is good, and the pressure-resistant hose 32 can be rolled into a bundle so that it can be easily carried without taking up space.

[0043]

As described above, according to the first and second aspects of the present invention, it is not necessary to use a special device, and the first pipe line, the second pipe line, and the pressurized air source are used. It is possible to collect groundwater at an arbitrary water level position in the pit easily and at a lower cost than the conventional method with a simple device such as installing the above. In addition, since groundwater is sampled only from the lower end of the bottom pipe in the pit, the flow of groundwater in the pit is quiet and does not disturb the groundwater flow field. Can be watered. Further, even when the target depth to be sampled is deep, it is sufficient to add pipes to make it longer, and thus the range of sampled water can be made wider than in the past. Further, as described above, it is possible to determine which depth of groundwater layer is contaminated by sampling groundwater of any depth and inspecting the quality of the water, and the effect on use is great. . Further, according to the invention of claim 3, in addition to the effect of claim 1 or claim 2,
There is no need for heavy equipment such as cranes to suspend hoses, and there are locking bodies such as piles for hanging pressure-resistant hoses near wells and vertical holes such as boring holes. As it can be rolled into a bundle, it is easy to carry around without taking up space. Further, according to the invention of claim 4, in addition to the effect of claim 1, claim 2 or claim 3, by introducing waste water into the water reservoir container and draining the waste water, The drainage of water can be made extremely easy, and the drainage of waste water can be swiftly and easily replaced with the water of the required depth, and the water of the required depth can be swiftly and easily obtained. Further, according to the invention of claim 5, in addition to the effect of the invention of claim 1, it is not necessary to use a special device, and only the air pressure source, the first pipeline, and the second pipeline are installed. With a simple device of
The inner wall of the pit can be easily and inexpensively washed compared to the conventional method using a pump, and all the groundwater in the pit can be easily cleaned. Further, it is not necessary to use a heavy machine such as a crane for suspending the first pipeline, and there is a locking body such as a pile for hanging the hose near the vertical hole, so that the hose can be easily supported. Since the hose has flexibility, it can be easily moved, and the hose can be rolled into a bundle so that it can be carried easily without taking up space.

[Brief description of drawings]

FIG. 1 is a vertical sectional view showing a water sampling device according to a first embodiment of the present invention.

FIG. 2 is a vertical cross-sectional view showing a situation where groundwater moves in the water sampling device according to the first embodiment of the present invention.

FIG. 3 is a vertical cross-sectional view showing a state in which pipes are added to the water sampling device according to the first embodiment of the present invention.

FIG. 4 is a vertical cross-sectional view showing a state in which groundwater has moved to a water sampling tank in the water sampling device according to the first embodiment of the present invention.

FIG. 5 is a vertical sectional view showing a water sampling device according to a second embodiment of the present invention.

FIG. 6 is a vertical cross-sectional view showing a situation where groundwater moves in the water sampling device according to the second embodiment of the present invention.

FIG. 7 is a vertical cross-sectional view showing a state in which a pipe is lowered in the water sampling device according to the second embodiment of the present invention.

FIG. 8 is a vertical cross-sectional view showing a state in which a pipe is lowered and groundwater is moved to a water reservoir in the water sampling device according to the second embodiment of the present invention.

FIG. 9 is a vertical cross-sectional view showing a state in which water is sampled in a water sampling tank in the water sampling device according to the second embodiment of the present invention.

FIG. 10 is a vertical sectional view showing a cleaning device according to a third embodiment of the present invention.

FIG. 11 is a vertical cross-sectional view showing a state in which a pressure-resistant hose is lowered in the cleaning device according to the third embodiment of the present invention.

FIG. 12 is a characteristic diagram showing the relationship between the length of the transparent pressure-resistant hose and the amount of pumped water in the third embodiment of the present invention.

[Explanation of symbols]

 2 Boring hole (vertical hole) 4 Groundwater 5 Pipe (first conduit) 9 Air supply hose (second conduit) 10 Communication pipe (first conduit) 11 Pipe (first conduit) 22 Pressure resistant hose (Water sampling hose) (First pipeline) 23 Water reservoir 28 Pile (locking body) 32 Pressure-resistant hose (hose) (first pipeline)

Claims (5)

[Claims] 1. A vertical hole formed by excavating the ground,
The first pipe line and the second pipe line are inserted from the ground in a state where the tip end portion of the second pipe line is inserted and arranged in the lower end opening of the first pipe line, and the first pipe line is inserted. In the state where the lower end opening of the is positioned at a predetermined depth in the groundwater that has sprung into the vertical hole, pressurized air is sent from the ground to the second pipeline to enter the first pipeline. A method for collecting groundwater in an underground pit, characterized in that the groundwater flowing in from the lower end opening is blown off by pressurized air ejected from the tip of the second pipeline and pumped to the ground side. 2. The method for collecting groundwater in the underground pit according to claim 1, wherein the second pipeline is a flexible air supply hose. Water way. 3. The groundwater sampling method in the underground pit according to claim 2, wherein a flexible water sampling hose is connected to the upper end of the first pipeline, and the peripheral part of the pit on the ground is connected. A locking body is provided, and the first hose is suspended in the water sampling hose with the water sampling hose locked to the locking body, and the water sampling hose is locked to the locking body. A method for collecting groundwater in an underground hole, wherein the depth position of the lower end opening of the first pipeline is changed by changing the position. 4. The method for collecting groundwater in the underground pit according to claim 3, wherein a water reservoir is provided on the water sampling outlet side of the water sampling hose, and the lower end opening of the first pipeline is connected to the ground water. Positioned at the water sampling depth, the groundwater in the first pipeline is introduced into the water reservoir and drained, and then the first water is further drained.
The method for collecting groundwater in the underground pit, wherein the groundwater flowing into the pipeline is introduced into the water reservoir to be used as the groundwater to be sampled. 5. The method for collecting groundwater in an underground hole according to claim 1, wherein both the first pipeline and the second pipeline are flexible hoses, and ground water is pumped by these hoses. At the same time, the wall surface in the pit is washed and the groundwater is cleaned, and the underground pit is washed.