JP3438097B2 - Leak detection system for impermeable sheet - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a water leak detection system for a water shield sheet at a final disposal site by a landfill hole for waste materials, and more particularly to a system for identifying the water leak location.

[0002]

2. Description of the Related Art A landfill waste disposal site is provided with a water-blocking sheet for preventing harmful waste liquid from dissipating from the waste. These water-blocking sheets have a structure that can prevent deterioration due to the environment and damage from external forces that accompany the introduction of waste. Including
There was a demand for early detection and repair of water leaks.

Therefore, various leak detection methods have been studied and implemented. As a typical example thereof, Japanese Patent Laid-Open No. 9-15
Japanese Patent Publication No. 081 discloses a water leakage detection system including three electrodes A, B and C in a water blocking structure constructed by a double water blocking sheet. A plurality of movable electrodes A, a surface electrode B arranged between two water-impervious sheets, and an electrode C laid on the ground are connected to a signal converter by drawing signal lines to form a circuit. It detects that the voltage and current between the electrodes change due to water leakage.

The above-mentioned known method is a method in which a voltage is applied by connecting a power source between electrodes and it is detected that an electric current flows due to water leakage, and the movable current A is measured from the ground to many points to be measured. There was a problem that it took time and effort to carry it, install it, and perform detection work.

[0005]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and it is not a method of carrying movable electrodes for detection, but an electrode group is provided in advance above and below a water-blocking sheet, respectively. A direct current voltage is applied between the electrode groups to perform polarization using the electrode reaction polarization phenomenon due to the electrolyte between the electrodes, and then the direct current voltage is turned off to measure the potential of the electrode and the leakage position. It is an object of the present invention to provide a water leakage detection system that utilizes a phenomenon in which the closer the metal electrode is, the faster the depolarization speed that attempts to return to the original state or the greater the depolarization amount becomes.

[0006]

In order to solve the above-mentioned problems, the water leakage detection system for a water-blocking sheet according to the present invention is an electrode made of a conductor above the water-blocking sheet laid on the bottom of an industrial waste disposal site. A first electrode group in which a plurality of electrodes are arranged, and a second electrode group including a plurality of conductor electrodes arranged in a lower portion of the water-blocking sheet so as to intersect with the first electrode group; In the water leakage detection system of the water blocking sheet, which includes a power source for applying a DC voltage between the electrode groups and a water leakage detection control unit for measuring the depolarization speed or depolarization amount, the water leakage detection control unit includes the first and second Means for short-circuiting each of the electrode groups, means for canceling the short-circuit of either the first or second electrode group after the application of the DC voltage, and the depolarization speed for each electrode of the electrode group whose short-circuit is released, or With a means to measure the amount of depolarization, the short circuit was opened. After measuring the depolarization speed or depolarization amount for each electrode of the pole group, short-circuiting is again performed for each of the first and second electrode groups, the polarity of the DC voltage is inverted and applied, and then the electrode group on the opposite side is applied. It is characterized in that the short circuit of is released and the depolarization speed or depolarization amount of each electrode is measured.

Further, the first and second electrode groups are characterized in that a plurality of electrodes are arranged in parallel at substantially equal intervals.

Further, the first electrode group and the second electrode group are arranged in a substantially orthogonal direction.

Further, it is characterized in that each electrode of the first and second electrode groups is made of a metal or carbon fiber having excellent corrosion resistance.

Further, each electrode of the first and second electrode groups is characterized by braiding conductive wires.

Each of the electrodes of the first and second electrode groups is a conductive wire made of any one of copper, aluminum, stainless steel, and carbon fiber, and the conductive wire is formed in a round or strip-shaped cross section. It is characterized by being.

The electrodes of the first and second electrode groups are
It is characterized by being composed of conductive wires made of different materials.

The first and second electrode groups are characterized by being fixed by weaving or adhering the electrodes to a waterproof sheet or a buffer sheet thereof.

Further, the water leakage detection control unit includes a system control computer, a DC power source and electronic control ON / OFF switches respectively connected to the first and second electrode groups, and an interface circuit for connecting the switches from the computer. ON / OF by the control signal output via
When the switch control circuit for F and the switch connected to one electrode group are in the OFF state, the potential of that electrode is measured with the potential of the other electrode group as a reference, and the measured value is passed through the interface circuit. And a potential measuring sequence circuit input to the computer.

Further, the water leakage detection control unit repeats from the short circuit of the upper and lower layer electrodes to the release of the short circuit / measurement of the depolarization potential by reversing the polarity of the DC power supply and repeating at the most depolarization speed in the first electrode group. Leakage position that selects the electrode with the fastest or large depolarization amount, the electrode with the fastest depolarization speed or the largest depolarization amount in the second electrode group, and specifies the vicinity of the intersection position coordinates as the leakage position It is characterized by comprising a specifying means.

Further, in a structure in which the impermeable sheets laid on the bottom surface of the industrial waste disposal site are provided in double or multiple layers, the upper and lower portions of each impermeable sheet provided in the multiple layers are substantially orthogonal to each other. A plurality of electrode groups are arranged, and water leakage is detected by using the upper electrode group of each water shield sheet as the first electrode group and the lower electrode group as the second electrode group.

Further, there is provided a measurement data transmitting means for transmitting the data measured by the water leakage detection system from a communication line connecting portion of the computer to a remote computer via a communication line, and the measurement data is stored in a database in the computer. It is characterized by recording and collectively managing the presence or absence of water leakage.

[0018]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows an embodiment of the structure of a water leakage detection system 1 for a water shield sheet according to the present invention. FIG. 2 is a diagram showing a detailed configuration of the water blocking sheet portion 10 in the water leak detection system 1.

In FIG. 1, reference numeral 20 denotes a water leakage detection control section, which includes a system control computer 50, interface circuits 41 and 42 having D / A and A / D conversion functions, a potential measurement sequence circuit 30, a switch control circuit 23, and It is composed of a DC power supply 25 and a communication line connection circuit section 43. The communication line connection circuit unit 43 communicates with the headquarters computer 100 via the Internet 90. In this embodiment, the DC power supply 25 is provided inside the water leak detection control unit 20, but it goes without saying that it can be provided outside the same.

Further, the system control computer 50
Is composed of a control unit 40, a ROM, and a RAM. The control unit 40 includes upper and lower layer electrode group short-circuiting means 40a, upper and lower layer electrode polarization means 40b, and short-circuit release / electrode depolarization potential measuring means 40c. A water leakage position specifying means 40d and a measurement data transmitting means 40e are provided.

First, the structure of the water blocking sheet portion 10 in the system 10 of the present invention will be described below with reference to FIG.

FIG. 2A shows the upper layer electrode group 11 woven into the nonwoven fabric 13. In this embodiment, the conductors are arranged in parallel at approximately equal intervals as shown in the figure, and are composed of m conductors.

FIG. 2B shows the water-blocking sheet 14,
(C) is an n-piece of water-shielding sheet 14 arranged on the opposite side of the upper electrode group 11 (first electrode group) in parallel at substantially equal intervals in a direction orthogonal to the respective electrodes of the upper electrode group 11. The state where the lower layer electrode group 12 (second electrode group) made of a conductor is woven into the nonwoven fabric 13 is shown. The interval between the upper layer electrode groups 11 does not have to match the interval between the lower layer electrode groups 12.
Further, the m conductors and the n conductors do not necessarily need to be arranged in parallel at substantially equal intervals, and the upper layer electrode group 11 and the lower layer electrode group 12 do not need to be orthogonal to each other.

FIG. 2D is a sectional view showing the basic structure of the water-blocking sheet portion 10. The water blocking sheet portion 10 is
Lower layer electrode group 1 woven into the nonwoven fabric 13 shown in FIG. 2 (c)
2, the water-blocking sheet 14 shown in FIG. 2 (b), and the upper layer electrode group 11 woven into the nonwoven fabric 13 shown in FIG. 2 (a). The non-woven fabric 13 serves as a protective mat that prevents damage from the upper part and damage from the lower ground.

FIG. 3 is a cross-sectional view of an embodiment of the water blocking sheet portion 10a in which the water blocking sheet has a double structure. The surface layer of the industrial waste disposal site is laid with a protective coating 2 such as sand to a specified thickness to protect the waterproof sheet from heavy equipment such as a waste carrier or the waste itself. 1
3, first electrode group 11, layer A up to the upper waterproof sheet 14, second electrode group 12, nonwoven fabric 13, lower waterproof sheet 1
It is composed of a B layer up to 4a, a third electrode 11a, a non-woven fabric 13, and a C layer up to a ground (base) 15.

In such a multilayer structure, the waterproof sheet 1
The intermediate electrode group provided between the electrodes 4 and 14a is shared and used for water leak detection. That is, in the water leak detection of the water shield sheet 14a, the water leak detection is performed using the second electrode group 12 serving as an intermediate electrode and the third electrode group 11a as the first electrode and the second electrode, respectively.

Next, referring to FIG. 1, the water blocking sheet portion 1 of FIG.
0 electrode terminal group 11 (11-1, 11-2, ..., 11
-M) and 12 (12-1, 12-2, ..., 12-n)
The water leak detection system 1 for identifying the water leak position by connecting to each other via the feeders 31 and 32 will be described in detail.

Here, reference numeral 20 denotes the overall structure of the water leakage detection control unit. System control computer 50 and DC power supply 25 for applying between upper layer electrode group 11 and lower layer electrode group 12
And the electric wires 31, 32 of the upper and lower electrode groups 11, 12
M / n electronic control ON / O
Turn ON / O the FF switch groups 21 and 22 and the DC power supply 25.
The DC power supply is turned on between the upper and lower electrode groups 11 and 12 by the FF switch 24 and the control signal output from the computer 50 via the interface circuit 41.
Switch on / off and switch groups 21 and 22 on
A switch control circuit unit 23 for controlling short-circuiting and release of the upper and lower electrode groups 11 and 12 by turning on / off, and the electrode groups 11 provided via the electric wires 31 and 32 of the respective electrodes.
When one electrode group switch (for example, the electrode group switch 21) of 12 is turned off, the potential measurement value of each electrode based on the potential of the other electrode group (here, the electrode group 22) is used as the interface circuit. And a potential measurement sequence circuit 30 to be input to the computer 50 via 42.

The operation of the detection system control computer 50 will be described.

The switch groups 21 and 22 are turned on via the switch control circuit 23 by a signal from the upper and lower electrode group short-circuit means 40a, and the upper and lower electrode groups are all short-circuited.

Next, the switch 24 of the DC power supply 25 is turned on via the switch control circuit 23 by the signal from the upper and lower layer electrode polarization means 40b, and the terminal A of the upper layer electrode group 11 and the terminal B of the lower layer electrode group 12 are turned on. And a voltage is applied to polarize the negative voltage side cathode through the electrolyte between the upper and lower electrodes. The DC power supply 25 includes a main switch control terminal 24.

Short circuit release / electrode repolarization potential measuring means 40c
Is a short circuit in which the switch 24 of the DC power supply 25 is turned off via the switch control circuit 23 and all the switches of the electrode group on the cathode side are turned off while the cathode on the negative voltage side is polarized. The electrodes are released, and the electrodes of the released electrode group are sequentially scanned through the potential measurement sequence circuit 30 and the potential is measured repeatedly at a predetermined cycle with reference to the other electrode group that is all in the short-circuited state. A change (depolarization speed) per unit time in the amount of depolarization that attempts to return to the original state from the polarized state or the potential at the time of measurement is measured to measure the difference from the potential in the polarized state (depolarization amount). . This depolarization speed or depolarization amount is measured for each electrode, and it is found that there is a leak near the electrode with the slowest depolarization speed or the electrode with the largest depolarization amount.

The water leakage position specifying means 40d is a means for releasing the short circuit / electrode repolarization potential measuring means 40 from the upper and lower layer short-circuit means 40a.
The measurement is repeated twice up to c, the first time, the upper electrode group 11 is all OFF, and the x electrode having the slowest depolarization is selected. Then, the second time, the lower electrode group 12 is all OFF, and the most depolarization is performed. The y electrode having a slower speed is selected, and the water leakage position z near the intersection is selected.

A concrete example thereof is shown in FIG. Figure 4
(A) is the electrode No. of the A layer (first electrode group). And the measured value of repolarization potential. The measurement results were repeated three times every second. From this measurement result, the electrode No. It can be seen that there is a leak position near 3.

FIG. 4B shows the electrode No. of the B layer (second electrode group). And the measured value of repolarization potential. The measurement results were repeated three times every second. From this measurement result, the electrode No. 5 and N
o. It can be seen that there is a leak position between 6 and 6.

As a result, as shown in FIG.
As shown in (c), the electrode No. of the layer A. 3 is A-3 and B
Electrode No. of the layer 5, B-5, electrode No. B that is 6
Judge that there is a water leakage position in the middle of -6. The electrode interval is 2 m, the applied voltage is 20 V15 minutes, the layer A is connected to the positive pole of the DC power supply (anode) in (a), the layer B is connected to the negative pole (cathode), and the layer A is connected in (b). The cathode and the B layer were used as the anode.

FIG. 5 is a diagram showing a flow chart of the water leakage detection system 1 of the present invention.

Steps S42 and S43 are the upper and lower layer electrode group short-circuiting means 40a. Step S44 is the polarization means 40b between the upper and lower electrodes. Steps S45 to S47 are the upper-layer electrode short circuit release / electrode repolarization potential measuring means 40c.

The above is the first measurement, and step S
The upper and lower electrode short circuit of 48 is the means 40a which starts the second measurement.

Step S49 is the second upper / lower electrode polarization means 40b. Steps S50 to S52 are the second short circuit release / electrode repolarization potential measuring means 40 of the lower layer electrode.
c.

Data analysis is performed in steps S53 and S54,
It is mapped as shown in FIG. Here, the water leak detection ends (S55), the modem is set from the computer 50, and the measurement data of the detection result is sent from the communication line connection unit 43 through the communication line 90 to the computer 10 of the water leak management company.
It is transmitted to 0 (S56, S57). (Measurement data transmitting means 40e)

If it is determined from the measurement data that there is no water leakage, the process is repeated from step S41 at a predetermined cycle. If it is determined that there is water leakage, the repository manager is notified and water leakage repair measures are taken (S58, S59, S60).

At the industrial waste disposal site using the double-layered waterproof sheet shown in FIG. 3, the leak detection between the A layer and the B layer was carried out by the above-mentioned method, and the leak up to the B layer was detected. In that case, it is further confirmed whether water is leaking from layer B to layer C. At this time, the second electrode group of the B layer is the upper layer electrode group,
It is confirmed that the third electrode group of the C layer is the lower layer electrode group and water is leaking to the C layer.

In such an industrial waste disposal site having a multi-layered structure, the formation of the C layer, the formation of the B layer, and the formation of the A layer are carried out in this order. For this reason, it is desirable to perform quality control, such as defective construction, at the seams at the stage of laying the water-impermeable sheets for each layer.

In the water leak detection system of the present invention, since the first electrode and the second electrode are made of conductive wires made of different materials, if there is water leak, the water leak can be detected from the potential difference due to different metals. it can.

That is, water leakage can be detected by short-circuiting the second electrode, applying a voltage higher than the natural potential, and sequentially measuring the potential of the first electrode group with the second electrode group as a reference. . This work can be easily performed by providing a voltage applying device and a tester on site. Even if a defective part is detected, it can be easily repaired and quality can be secured because it is in the process of being constructed.

The material of the conductors of the upper and lower electrode groups is preferably metal such as stainless steel or the like having excellent corrosion resistance, or carbon fiber.

The shape of each electrode of the upper and lower electrode groups made of this conductor may be a band shape in which a plurality of electrode wires are braided for each electrode and the strength of the bed is strengthened.

Each of the electrodes of the first and second electrode groups is a conductive wire made of any one of copper, aluminum, stainless steel and carbon fiber, and the conductive wire has a round or strip-shaped cross section. To use.

The upper and lower electrode groups made of the above conductors are arranged in a sheet of nonwoven fabric in parallel with the electrode group and woven or attached, or a resin is attached to the nonwoven fabric at predetermined positions. But it's okay.

By providing the computer 100 at a remote place where a water leakage management company is provided, it is possible to record the measurement data in the database and collectively manage the presence or absence of water leakage. Therefore, it is possible to monitor the occurrence of water leakage without incurring the cost of allocating a specialist at the site of the industrial waste disposal site.

As is clear from the above description, the present invention includes the following technical ideas. (1) In a water leakage detection system for water-blocking sheets laid on the bottom of an industrial waste disposal site, the m water-blocking sheets are arranged in parallel at approximately equal intervals on either the upper or lower layer of the water-blocking sheet. A first electrode group made of a conductor and n pieces of electrodes arranged in parallel to each other on the side opposite to the first electrode group with respect to the water-blocking sheet in a direction orthogonal to the first electrode group at substantially equal intervals. A second electrode group made of a conductor is connected to one end of each electrode of the first and second electrode groups via an electric wire, and a DC voltage is applied between the first electrode group and the second electrode group. And a water leak detection control unit that measures the voltage between them to identify the water leak location. The water leak detection control unit is provided between the system control computer and the first electrode group and the second electrode group. A DC power source for applying the voltage and m provided through each electric wire of the first and second electrode groups. , N electronically controlled ON / OFF switch groups and the DC power supply in a predetermined order between the first electrode group and the second electrode group according to a control signal output from the computer via the interface circuit to the switch groups. A switch sequence circuit section for turning ON / OFF the
When one of the electrode group switches provided via the electric wires of the respective electrodes is in the OFF state, the potential value of the OFF electrode can be measured with reference to the potential of the other electrode group.
And a potential measuring sequence circuit for inputting measured values from n potential measuring wirings to the computer through an interface circuit, and turning on the switches for all of the first and second electrode groups. The upper and lower electrode group short-circuiting means and the first and second DC voltages are applied with all the switches to the upper and lower electrode groups being turned on, and the positive electrode and the negative potential on the positive potential side and the negative potential are applied by the electrolyte between them. And a means for polarizing between upper and lower layer electrodes for polarizing between the negative electrodes on the side, and a short circuit release for turning off all switches of either the first or second electrode group when the upper and lower layer electrodes are in a polarized state. At the same time, the electrodes of the released electrode group are sequentially scanned, and the potential is measured with the other electrode group that is all in the ON state as a reference, and the measurement is repeated in a predetermined synchronization, and the polarization of each electrode is in the original state. Back to And a short-circuit release / electrode depolarization potential measuring means for measuring the time variation of the potential of Utosuru depolarization, and identifies a leak position from the delay time difference depolarization.

[0053]

EFFECTS OF THE INVENTION The water leakage detection system for water-blocking sheets of the present invention has the following effects.

In the water leakage detection system for the water blocking sheet of the present invention, the detection electrodes arranged in parallel in advance are arranged and laid so that the respective electrodes are orthogonal to the upper and lower layers of the water blocking sheet. By measuring the repolarization speed or the repolarization amount of polarization by each electrode and detecting the electrode with the highest depolarization speed for each of the upper electrode group and the lower electrode group, the leakage position can be easily determined from the intersection of the electrodes. Can be estimated.

The detection work is easier and less costly than in the prior art. That is, it is not necessary to install a detection moving electrode for identifying a damaged portion in a vast disposal site.

[Brief description of drawings]

FIG. 1 is a configuration diagram of a water leakage detection system of the present invention.

FIG. 2 is a basic structural diagram of a water-blocking sheet portion of the present invention.

FIG. 3 is a structural diagram of an embodiment of a double structure of the water-blocking sheet portion of the present invention.

FIG. 4 is a diagram showing measured data for detecting a water leakage position of the present invention.

FIG. 5 is a flow chart of the water leakage detection system of the present invention.

[Explanation of symbols]

1 Water Leakage Detection System 2 Protective Coating 10 for Sand etc. Impermeable Sheet Part 10a Impermeable Sheet Part (Double Structure) 11 m Upper Layer Electrode Group Woven in Nonwoven Fabric and Its Electrode Terminal Group (First Electrode Group) 11a 3 electrode group 12 n lower layer electrode group woven in non-woven fabric and its electrode terminal group (second electrode group) 13 non-woven fabric (protective sheet) 14 water-impervious sheet 14a water-impervious sheet 15 ground (ground) 20 leak detection control Part 21 (21-1, 21-2, ..., 21-m) m electronic control switch group 22 (22-1, 22-2, ..., 22-n) lower electrode group on the upper electrode group side Side n electronic control switch group 23 application switch sequence circuit 24 main switch control terminal 25 of DC power supply 25 DC power supply 30 for application between upper and lower layer electrodes potential measurement sequence circuit 31 upper layer electrode group m electric wires 32 lower layer electrode group N electric wires 40 Control unit (CPU) 40a Upper and lower layer electrode group short-circuit means 40b Upper and lower layer electrode polarization means 40c Short circuit release / electrode repolarization potential measuring means 40d Leakage position specifying means 50 Detection system control computer 41, 42 interface Part 43 Communication line connection part including modem 50 System control computer 90 Communication line 100 Water leak detection management company headquarters computer

─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Hiroshi Sasaki 2 Sanbancho, Chiyoda-ku, Tokyo Tobishima Construction Co., Ltd. (72) Inventor Yasushi Arakawa 2 Sanbancho, Chiyoda-ku, Tokyo Tobishima Construction Co., Ltd. In-house (72) Inventor Hideki Ueda 1-21-12 Minami Kamata, Ota-ku, Tokyo Inside Nihon Corrosion Protection Co., Ltd. (72) Inventor Kenkichi Tashiro 1-29-10 Maeno-cho, Itabashi-ku, Tokyo No. Japan Technical Research Institute Co., Ltd. (56) Reference JP-A-9-15081 (JP, A) JP-A-9-33382 (JP, A) JP-A-9-243581 (JP, A) JP 10-332522 (JP, A) JP 2000-352541 (JP, A) JP 2001-99742 (JP, A) JP 2001-324406 (JP, A) JP 2002-122504 (JP, A) (JP) 58) Fields investigated (Int. Cl. ⁷ , DB name) G01M 3/00-3/40

Claims (12)

(57) [Claims] 1. A first electrode group in which a plurality of electrodes made of a conductor are arranged on an upper portion of a waterproof sheet laid on the bottom surface of an industrial waste disposal site, and a first electrode is disposed below the waterproof sheet. A second electrode comprising a plurality of conductor electrodes arranged to intersect the group
In the water leakage detection system for a water-impervious sheet, comprising: the electrode group, a power source that applies a DC voltage between the first and second electrode groups, and a water leakage detection control unit that measures the depolarization speed or depolarization amount. The detection control unit includes means for short-circuiting each of the first and second electrode groups, means for releasing short-circuiting of either the first or second electrode group after application of a DC voltage, and electrodes for which the short-circuit has been released. Means for measuring the depolarization speed or depolarization amount of each electrode of the group, and after measuring the depolarization speed or depolarization amount of each electrode of the electrode group whose short circuit has been opened, the first and second electrodes are again measured. After short-circuiting every two electrode groups and applying the voltage after reversing the polarity of the DC voltage,
A water leakage detection system for a water-blocking sheet, which measures the depolarization speed or depolarization amount of each electrode by releasing the short circuit of the electrode group on the opposite side. 2. The water leakage detection system for a water-blocking sheet according to claim 1, wherein the first and second electrode groups have a plurality of electrodes arranged in parallel at substantially equal intervals. 3. The first electrode group and the second electrode group are arranged in a substantially orthogonal direction.
The water leak detection system for the water blocking sheet according to 2. 4. The water leakage of the waterproof sheet according to claim 1, wherein each electrode of the first and second electrode groups is made of metal or carbon fiber having excellent corrosion resistance. Detection system. 5. The water leakage detection system for a waterproof sheet according to claim 1, wherein each electrode of the first and second electrode groups is a braided conductive wire. 6. Each of the electrodes of the first and second electrode groups is a conductive wire made of any one of copper, aluminum, stainless steel, and carbon fiber, and the conductive wire is formed in a circular or strip-shaped cross section. The water leakage detection system for water-blocking sheets according to claim 1, wherein 7. The water leakage detection system for a waterproof sheet according to claim 1, wherein the electrodes of the first and second electrode groups are made of conductive wires made of different materials. 8. The method according to claim 1, wherein the first and second electrode groups are fixed by weaving or adhering the electrodes to a water blocking sheet or a buffer sheet thereof. Leakage detection system for water barrier sheets. 9. The water leakage detection control unit includes a system control computer, a DC power source, and electronic control ON / OFF switches connected to the first and second electrode groups, respectively.
A switch control circuit for turning on / off those switches by a control signal output from the computer through an interface circuit, and a potential of the electrode when the switch connected to the one electrode group is turned off, the other electrode group. 9. The water leakage detection system for a water-blocking sheet according to claim 1, further comprising: a potential measurement sequence circuit that measures each of the potentials as a reference and inputs the measured value to the computer through an interface circuit. . 10. The water leakage detection control unit repeats from the short circuit of the upper and lower electrodes to the release of the short circuit / measurement of the depolarization potential by reversing the polarity of the DC power source and repeating the most depolarization speed in the first electrode group. Leakage position that selects the electrode with the fastest or large depolarization amount, the electrode with the fastest depolarization speed or the largest depolarization amount in the second electrode group, and specifies the vicinity of the intersection position coordinates as the leakage position The device according to claim 1, further comprising a specifying unit.
To 9. The water leakage detection system for water-blocking sheets according to 9 above. 11. In a structure in which the impermeable sheets laid on the bottom surface of the industrial waste disposal site are provided in double or multiple layers, the upper and lower portions of each impermeable sheet provided in the multiple layers are substantially orthogonal to each other. A plurality of electrode groups are arranged, and water leakage is detected by using the upper electrode group and the lower electrode group of each water-blocking sheet as the first electrode group and the second electrode group, respectively. Leakage detection system for the water-blocking sheet described. 12. A measurement data transmitting means for transmitting data measured by the water leakage detection system to a computer at a remote place from a communication line connection section of the computer via a communication line, and the computer stores the measurement data in a database. The water leakage detection system for a water-blocking sheet according to claim 1, wherein the water leakage detection system records the data and collectively manages the presence or absence of water leakage.