JPH08226143A - Underground water sampling method and sampling device - Google Patents

Abstract

PURPOSE: To properly sample underground water from a plurality of depth levels at one point. CONSTITUTION: A water sampling device is provided with a plurality of water sampling tubes 9, each having a water intake port at one end, divisional members 15 capable of expansion upon receipt of water, and a suction device connected to the other end of each tube 9. Also, each tube 9 is fitted with a filter having a mean aperture diameter between 0.05mm and 0.2mm. Furthermore, each single hole having a strainer is formed at a plurality of desired depth levels, and the tube 9 is inserted in the hole so as to keep the intake port positioned near a desired depth level. Also, the members 15 are arranged between each intake port, and caused to expand as a result of water absorption, thereby separating the internal space of the single hole for isolating the water intake ports from each other. Then, water is sampled with the suction device through the tubes 9. According to this construction, underground water can be efficiently sampled over a long time and at the same time, properly sampled from many depth levels at one point.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and apparatus for collecting soil water and groundwater in the ground, and more particularly to a technique for collecting groundwater at a plurality of depths at the same point.

[0002]

2. Description of the Related Art Groundwater is one of the natural water resources that can be effectively used, and is used as drinking water, industrial water, etc. because it provides high quality water due to the filtering action of soil. However, in recent years, environmental pollution and depletion of groundwater have become problems, and there is a need for comprehensive management / analysis of information on groundwater in a wider area and planned use of groundwater. For this reason, studies are underway to study the geological structure, the direction of groundwater flow, its velocity, etc., and to three-dimensionally understand the quality of groundwater.

A groundwater sampling technique is important for three-dimensional understanding of groundwater. In conventional water sampling, wells were used for groundwater sampling. In this method, one strainer (hole for taking in groundwater) is opened in one well, and a water sampling pipe is introduced into the well to collect water in the well, thereby achieving water sampling at the depth of the strainer.

[0004]

However, in this method, only one well can collect water at one depth,
In order to collect water at multiple depths, it is necessary to install multiple observation wells with different depths. However, such a coping method does not strictly allow observation at the same point, and there is a physical limit to the number of observation wells to be installed, resulting in a great amount of labor for installation.

Further, when water is sampled at an observation well, the water contained in groundwater often causes clogging of the water sampling pipe, which hinders observation.

The present invention has been made in order to solve the problems of the prior art as described above, and enables efficient and accurate information collection of groundwater. It is an object of the present invention to provide a water sampling method and device that ensures reliable water collection.

[0007]

[Means for Solving the Problems] In order to achieve the above object, the inventors of the present invention have conducted extensive studies, and as a result, by devising a water sampling pipe, it is possible to collect a plurality of water in one observation well. It was found that there was such a problem, and the inventors have invented the water sampling method and device of the present invention.

The water sampling method of the present invention comprises the steps of installing a single hole having a strainer at a plurality of desired depths, and introducing a plurality of water sampling pipes each having a water intake port at one end into the single hole. The step of positioning the water intake of the water pipe in the vicinity of the desired depth, and the partition member that expands due to water absorption are arranged so as to be positioned between the water intake strainers so that water is absorbed and each water intake is shut off. The method is characterized by including a step of partitioning the inside of the hole with an expanded partition member and a step of collecting water from each of the water sampling pipes from the single hole partitioned by the partition member.

Further, the water sampling device of the present invention has a plurality of water sampling pipes each having an intake port at one end and introduced into a single hole so that the intake port is located near a desired depth, and the inside of the single hole. A partition member that is disposed between the water intakes of the water sampling pipe and partitions the inside of the single hole so as to expand by water absorption and block the water intakes, and through the water sampling pipe from the single hole partitioned by the partitioning member A suction device connected to each of the other ends of the water sampling pipe for sampling water is provided.

Further, the water sampling device of the present invention comprises a water sampling pipe having a water inlet at one end and a filter having an average opening diameter of 0.05 mm to 0.2 mm attached to the water inlet.

[0011]

A single hole having a strainer is installed at a desired depth, a plurality of water sampling pipes are introduced into the installed single hole, and the water intake port of the water sampling pipe is positioned near the desired depth. When the partition members are arranged between the strainers and each partition member absorbs the water in the single holes and expands, the expanded partition members partition the inside of the single holes between the strainers, and the strainers are blocked from each other. It Groundwater flows into each region partitioned by the partition member from the strainer in the region. When water is taken through each water sampling pipe, the water in the area partitioned by the partition member is separately sampled. Therefore, groundwater at multiple depths in a single hole is sampled separately.

The water sampling pipe of the water sampling device has a filter attached to the water intake port, and the average opening diameter of the filter is 0.05 mm.
By the above, the filter is prevented from being clogged by the earth and sand in the groundwater, and further, the clogging in the water sampling pipe is prevented by setting the diameter to 0.2 mm or less.

The present invention will be described in more detail below with reference to the drawings.

In order to enable water sampling at one point at multiple depths, in the present invention, as shown in FIG. 1, a single hole 1 is excavated at the water sampling point as a water sampling hole, and this single hole is drilled. 1 is provided with strainers (holes for taking groundwater into the water intake port) 3 at desired depths. The single hole 1 can be installed by using a normal technique. Specifically, a single hole is excavated in the ground by a boring machine or an auger. In order to ensure the position of the strainer 3 accurately and surely, a metal pipe 7 or the like having an opening 5 at a position corresponding to the depth of the strainer as shown in FIG. 2 may be fitted into the single hole 1. By using such a pipe, the pipe acts as an inner wall surface of a single hole, and the strainer can be easily positioned. As the water sampling holes, wells provided with strainers at regular intervals may be used. The area of the strainer with respect to the surface area of a single hole is called "aperture ratio". Groundwater can be collected well if the open area ratio is about several percent, although it varies slightly depending on the type of stratum.

Water sampling pipes 9 are inserted into the above-mentioned single hole in accordance with the number of depth points for water sampling. There is an intake port 11 at the tip of each intake pipe, and the insertion condition of the intake pipe is adjusted so that the intake port 11 is located at a desired depth. In order to properly position the intake port 11 at the target depth, it is desirable to appropriately set the material, wall thickness, etc. of the water sampling pipe 9 so that the water sampling pipe 9 is less likely to deform and has lower flexibility. If the water sampling pipe 9 is easily deformed or bent, when it is inserted into the single hole 1, the water sampling pipe 9 will be bent by the earth and sand, etc., and the position of the water intake 11 will not be accurately determined, or it will reach the target depth. Or not.

A filter 13 is preferably attached to the water intake 11 of the water sampling pipe 9 in order to prevent dirt and gravel in the ground from being taken into the water sampling pipe 9. The opening diameter of the filter 13 greatly affects the water sampling efficiency of the water sampling pipe 9. Filter 1
When the opening diameter of 3 is small, the filter 13 itself is likely to be clogged, and when the opening diameter is large, the clogging of the filter 13 is not generated, but small particles of earth and sand which have passed through the filter 13 are aggregated in the water sampling pipe 9. , The water sampling pipe 9 is closed.
From such a viewpoint, it is preferable to use the filter 13 having an average opening diameter of 0.05 mm to 0.2 mm as the filter 13 used for collecting groundwater. As such a material, for example, a hard porous body made of a synthetic resin such as polypropylene or a nylon mesh can be used,
Examples of commercially available hard porous materials suitable for use include Pearlcon HP-35 (trade name, manufactured by Daicel Chemical Industries),
Pearlcon HP-12 (same as left) and the like can be mentioned. By using such a filter, it is possible to continue water sampling for a long time without clogging the thin water sampling tube, and it is possible to sample water using a single hole having a small inner diameter.

Since the single hole 1 is provided with a plurality of strainers 3, the groundwater of various depths is mixed by the circulation of the water in the single hole 1 as it is. In order to prevent this, a partition member 15 for partitioning the inside of the single hole 1 is arranged in the single hole 1 together with the water sampling pipe 9. For the partition member 15, it is preferable to use a sealing material 17 made of a material that expands by absorbing water. Examples of such a sealing material 17 include a sheet-shaped sealing material made of polyacrylic acid ester and SBR synthetic rubber. In the case of this sealing material, it expands about 20 to 25 times due to water absorption. When the sealing material 17 having such expansiveness is wound around the water sampling pipe 9 and introduced into the single hole 1, the sealing material 17 absorbs groundwater and expands, and spreads from above the water sampling pipe 9 in the radial direction to expand the sealing material 17. The water above and below is cut off from each other to form a partitioning member 15 for vertically partitioning the inside of the single hole 1. Therefore, if the partition member 15 is arranged at the depth between the strainers 3, the water in the single hole 1 is not mixed, and the groundwater is separately accumulated for each strainer 3. As a result, the water in each of the partitioned areas is collected in the water sampling pipe 9
If the water is sampled through, the collected water becomes groundwater at the depth of the strainer 3 in the partitioned area where the water intake 11 (or the filter 13) of the water sampling pipe 9 is located. Therefore, it is possible to collect groundwater by depth.

In order to arrange the partition member 15 in this manner, for example, as shown in FIG. 2, a plurality of water sampling pipes 9 to be inserted into the single hole 1 are bundled, and the water intake of the water sampling pipe 9 inserted into the single hole 1 is performed. The water intake 11 (or the filter 13) is shifted so that the mouth 11 (or the filter 13) and the strainer 3 correspond to each other, and the seal material 17 is placed so that the seal material 17 is located between the water intakes 11. You can wind it around 9. The sealing material 17 is appropriately adjusted so that the winding amount increases as the depth increases. By inserting this bundle of water sampling tubes 9 into the single hole 1, the water intake 11 (or the filter 1
3) Each strainer 3 due to the sealing material 17 expanded between
The partition member 15 that blocks the space is formed. When a gap is formed between the water sampling pipes when the water sampling pipes are bundled, a bond or a packer may be used for blocking.

In order to obtain accurate groundwater information, it is optimum that the strainer 3 for supplying groundwater to one region partitioned by the partitioning member 15 has only one depth, but the required water sampling is required. It is also permissible for the strainers 3 of multiple depths to be within one region, depending on the accuracy. In particular, when a pipe 7 having openings 5 provided at regular intervals along the longitudinal direction as shown in FIG. 2 is inserted into the excavated single hole 1 to form a water sampling hole, a strainer is appropriately used as necessary. 3 can be divided into groups and arrangement | positioning of the division member 15 and the water intake 11 can be devised.

A partition member is preferably attached above the water intake arranged at the shallowest part of the single hole in order to prevent rainwater and the like from flowing in from the outside of the single hole.

The mode of the partition member 15 described above can be appropriately changed in consideration of the convenience in use. For example, a sealing material is formed into a disc shape with the above-mentioned expansive material,
A plurality of holes for penetrating the water sampling pipe 9 may be provided and used as a partition member. Further, in order to improve the conformability of the single hole to the inner wall at the time of expansion, concentric concavities and convexities may be provided so that the sealing material has a bellows-shaped cross section.

A suction device is connected to each of the other ends of the water sampling pipes in order to collect water from the region partitioned by the partition member 15 through the water sampling pipe 9. The suction device is a container 19 for receiving water.
And a decompression pump 21 connected thereto. By operating the decompression pump 21 to decompress the water sampling pipe 9 through the container 19, the groundwater in the single hole 1 is sucked and stored in the container 19. Of course, in order to collect water from the plurality of water sampling pipes 9 by one decompression pump, the plurality of containers 19 connected to each water sampling pipe 9 and the decompression pump 21 are connected via the branch pipe and the switching cock. Good. Further, when the filter is clogged, a fluid (water or air) may be reversely flowed from the water sampling pipe to the filter to remove the clogging.

With the above structure, since it is possible to collect groundwater from a single hole at multiple depths, it is possible to easily observe groundwater according to the present invention. In addition, since it is possible to collect groundwater using a pipe with a diameter of 1 cm or less, a single hole with a diameter of about several cm is sufficient as a well for water sampling, so drilling a well with a large diameter,
It is not necessary to provide many wells.

Furthermore, by switching the connection between each water sampling pipe and the decompression pump as necessary, it is possible to perform water sampling in which the depth of water sampling needs to be changed. An operation control device may be incorporated in the suction device, and the switching may be controlled according to the water intake time or the detected water quality. Although the quality and quantity of groundwater are essentially unchanged, the quality and quantity of groundwater have tended to change recently due to the effects of artificial increase and environmental pollution, so it is necessary to change the intake depth for general groundwater collection. Can be addressed using the present invention. Furthermore, the present invention can be applied not only to groundwater but also to a system for collecting liquid resources such as oil and the like from the ground when it is necessary to collect at multiple depths or to change the collection depth.

[0025]

EXAMPLES The present invention will be described in more detail below with reference to experimental examples.

(Experimental Example 1) A single hole having a depth of 7.7 m was excavated in the ground in the vertical direction, and an iron pipe having an inner diameter of 40 mm having a hole serving as a strainer as shown in FIG. 2 was formed into a single hole. It was fitted to form a well for water sampling. The diameter of the hole in the iron pipe is 5
mm, 4 holes are opened at 90 degree intervals in 4 directions.
Two holes were arranged at intervals of 2 cm in the longitudinal direction with the opening direction shifted by 45 degrees, and the opening ratio was 3.1%. The hole, that is, the strainer, was located at a depth of 2.7 to 7.2 m below the ground surface.

A filter composed of a polypropylene hard porous body (trade name: Pearlcon HP-35, manufactured by Daicel Chemical Industries, Ltd.) having a length of 10 cm and a diameter of 8 ± 2 mm at the tip of a polyvinyl chloride pipe having an inner diameter of 6 mm and an outer diameter of 8 mm. 2 to form a water sampling pipe, the filter positions are shifted by 1 m in the same manner as in FIG. 2, and five water sampling pipes are bundled, and each of the water sampling pipes has a width of 4 cm and a thickness of 0. A 3 cm polyacrylic ester / SBR rubber sealing material (trade name: Niceseal B type, manufactured by Applied Geology Co., Ltd.) was wound around each 3 rolls. The sealing material arranged at the shallowest position was a single winding, and for the seals deeper than that, the number of windings was appropriately increased according to the depth.

A bundle of water sampling tubes wound with a seal was inserted into the water sampling well described above, and each filter was set to 3 m, 4 m, 5 m,
The water sampling pipe was fixed so as to be located at a depth of 6 m and 7 m, respectively. The seal swelled due to water absorption, and after standing for one day, the seal obstructed between the filters. After this, a 2000 cc capacity glass bottle was connected to each water sampling tube, and a diaphragm type vacuum pump (model: DA-5D, manufactured by Vacuum Kiko Co., Ltd.)
The pressure was reduced using and water was collected from each water sampling pipe. At this time, the groundwater level in the well is 2.5m below the ground surface,
It took about 3 minutes to collect cc of groundwater into each bottle.

(Experimental Example 2) The same polyvinyl chloride pipe as that used in Experimental Example 1 and various materials shown in Table 1 were used to form a water sampling pipe with a filter. Nylon mesh and laminated sintered wire mesh as a filter material (5 layer stainless steel wire mesh laminated and sintered and having a thickness of 1.5 to 1.8 mm, product name: New PoreMet, Central Filter Industry Co., Ltd.)
In the case of using, each was formed by cutting a net into a square having a side of about 10 cm, winding the mesh in a cylindrical shape, and bending and sealing the tip. Ultra high molecular weight high density polyethylene (Opening ratio 38
%, Trade name: UHE-1400, manufactured by Daicel Chemical Industries, Ltd. and hard polypropylene porous body (opening ratio 38%, trade name: Pearlcon HP-12, HP-35, manufactured by Daicel Chemical Industries, Ltd.) Length 10 cm, diameter 8
It was processed into a cylinder of ± 2 mm and connected to the open end of the tube.

Using the above-mentioned filter, suction water of muddy water (particle size distribution of contained particles: 0.003 to 5 mm) was reduced to about 0.
After 5 hours, the presence or absence of clogging of the filter and clogging of the water sampling pipe was examined. Table 1 shows the results.

[0031]

[Table 1] −−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−− Filter Material Average Opening Diameter Water Permeability Evaluation (mm) (cm / sec) Filter tube Clogged Blockage −−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−− Laminated sintered wire mesh 0 .02 0.1-0.3 Yes-Ultra high molecular weight high density polyethylene 0.02 0.1-0.3 Yes-Nylon net 0.1 ∞-Hard polypropylene porous body (HP-35) 0.1 ∞ − − Rigid polypropylene porous body (HP-12) 0.3 ∞ − Wire mesh 0.5 ∞ − Yes No (tube only) ∞ − Yes −−−−−−−−−−−−−− −−−−−−−−−−−−−−−−−−−−− As is clear from the above results, when the average aperture diameter of the filter is large, it passes through the filter. Particles are clogging the tube to aggregate at the tube, the average opening diameter of the filter is small,
Although the blockage of the pipe is prevented, the clogging of the filter occurs and the water intake time becomes shorter. In other words, it is considered that mixing of silty or clay-like components into the water sampling pipe does not adversely affect water sampling, and therefore coarse sand and gravel can be removed and the average opening diameter is about 0.05 to 0. A filter with a range of 0.2 mm can collect water efficiently and is suitable for groundwater sampling.

[0032]

As described above, the water sampling device of the present invention can efficiently collect groundwater for a long time and can accurately sample water at multiple depths at one point. Therefore, its industrial value is extremely large.

[Brief description of drawings]

FIG. 1 is a conceptual diagram showing a configuration of a water sampling device of the present invention.

FIG. 2 is a conceptual diagram showing an assembly structure of a water sampling pipe of the water sampling device of the present invention.

[Explanation of symbols]

 1 Single hole 3 Strainer 9 Water sampling pipe 13 Filter 15 Partition member 17 Sealing material 19 Container 21 Decompression pump

Claims (3)

[Claims] 1. A step of installing single holes each having a strainer at a plurality of desired depths, and a plurality of water sampling pipes each having a water intake port at one end thereof are introduced into the single hole, and the water intake port of each water sampling pipe is set at A step of locating in the vicinity of a desired depth, and a partition member that expands due to water absorption is arranged so as to be located between the water intake ports and absorbs water to expand the inside of a single hole so as to block each water intake port. And a step of collecting water through each of the water sampling pipes from a single hole partitioned by the partition member. 2. A plurality of water intake pipes, each of which has a water intake at one end and is introduced into a single hole so that the water intake is located near a desired depth, and each water intake of the water intake pipe in the single hole. A partition member that is disposed between the partition holes and partitions the inside of the single hole so as to block between the water intake ports, and the water sampling pipe for collecting water through the water sampling pipe from the single hole partitioned by the partition member. And a suction device connected to each other end of the ground water. 3. A water sampling pipe having a water intake at one end, and an average opening diameter attached to the water intake is 0.05 mm to 0.2 mm.
A ground water sampling device, characterized by comprising: