A Sampling Site Layout Method for Investigating Soil Pollution Status in Geophysical Exploration

Abstract

The present invention provides a method for sampling and arranging points for investigating soil pollution status in geophysical exploration, which belongs to the technical field of sampling and arranging points for contaminated soil. The method obtains the potential contaminated area in the plot where the soil to be explored is located by the resistivity method, obtains the high-risk area in the plot according to the original functional layout map of the plot, and arranges sampling points in the potential contaminated area and the high-risk area. The present invention solves the problem that the existing technology uses production-related areas in contaminated soil as high-risk areas for sampling, which easily misses other contaminated areas in the contaminated soil, making the sampling results inconsistent with the actual pollution situation. The present invention has the advantage of covering most of the contaminated areas in the contaminated soil with sampling points, so that the sampling results are consistent with the actual pollution situation.

Description

Technical Field

[0001] The present invention relates to the technical field of sampling and arranging points for contaminated soil, and in particular to a sampling and arranging method for investigating soil contamination status in geophysical exploration. Background Art

[0002] When soil is contaminated, its color changes, generally turning into black, dark brown, dark gray, brown red, apricot red, or with rust spots, etc., which is different from the color of normal soil; the state also changes accordingly, such as the original plastic hard plastic state will turn into soft plastic or fluid plastic; the contaminated soil layer often has a honeycomb structure, dispersed particles, rough surface, and even local holes.

[0003] Before sampling and testing contaminated soil, existing technologies often use the original functional layout of the contaminated soil to select production-related areas as high-risk areas for sampling. However, this sampling method is likely to miss other contaminated areas in the contaminated soil, making the sampling results inconsistent with the actual pollution situation. Summary of the Invention

[0004] The technical problem solved by the present invention is that the existing technology uses production-related areas in contaminated soil as high-risk areas for sampling, which easily misses other contaminated areas in the contaminated soil, making the sampling results inconsistent with the actual pollution situation.

[0005] To solve the above problems, the technical solutions of the present invention are as follows:

[0006] A sampling point arrangement method for geophysical exploration soil pollution status investigation, comprising:

[0007] Obtain the stratigraphic structure and soil properties of the plot where the soil to be explored is located and its surrounding areas;

[0008] Obtain the resistivity difference between the plot soil and the surrounding normal soil. If there is a difference between the two, measure the resistivity of the plot soil using the resistivity method.

[0009] Determine a three-dimensional geological model of the plot containing the distribution range of abnormal soil based on the resistivity of the plot soil, extract the edge coordinates of the abnormal soil distribution range in the three-dimensional geological model of the plot, project the edge coordinates onto a map of the plot, and obtain the potential contaminated area of the plot;

[0010] Based on the original functional layout map of the land parcel, obtain the high-risk areas of the land parcel;

[0011] Sampling points are set up in the potential contaminated area of the plot, sampling points are set up in the high-risk area of the plot, and sampling points are densely distributed in the area where the potential contaminated area of the plot overlaps with the high-risk area of the plot.

[0012] As one aspect of the present invention, obtaining the resistivity difference between the soil of a plot and the surrounding normal soil includes:

[0013] Obtain characteristic pollutants related to the resistivity of the plot, set up soil test groups according to the characteristic pollutants, measure the soil resistivity of each soil test group, and obtain the difference between the soil resistivity of the plot soil and the soil resistivity of the normal soil around the plot to be tested. Based on the difference, preliminarily determine whether the plot contains landfill and obtain a preliminary judgment result. If the preliminary judgment result is that the plot contains landfill, proceed to the next step;

[0014] Among them, the relevant data of characteristic pollutants include the types of characteristic pollutants and the pollution equivalents of characteristic pollutants; the soil test groups include blank control group, one-time pollution equivalent test group, three-time pollution equivalent test group and five-time pollution equivalent test group; the blank control group is the normal soil around the plot soil, the one-time pollution equivalent test group is the plot soil, the three-time pollution equivalent test group is the plot soil with three times the pollution equivalent of the characteristic pollutants, and the five-time pollution equivalent test group is the plot soil with five times the pollution equivalent of the characteristic pollutants.

[0015] As another aspect of the present invention, the resistivity of soil of a plot of land is measured by a resistivity method, comprising:

[0016] A plurality of measuring lines are set at equal intervals in the plot, a plurality of measuring points are set at equal intervals on the measuring lines, the resistivity of all measuring points is measured by the resistivity method, and the resistivity of all measuring points is determined as the resistivity of the soil in the plot.

[0017] As another aspect of the present invention, obtaining high-risk areas of a land parcel based on the original functional layout diagram of the land parcel includes:

[0018] Based on the original functional layout map of the plot, the production-related areas in the plot are identified as high-risk areas of the plot through professional judgment.

[0019] As another aspect of the present invention, the production-related area in the plot includes the original production area and the wastewater treatment facility area.

[0020] As another aspect of the present invention, sampling points are arranged in a potential contaminated area of a plot of land, sampling points are arranged in a high-risk area of the plot of land, and sampling points are arranged densely in an area where the potential contaminated area of the plot of land overlaps with the high-risk area of the plot of land, including:

[0021] Divide the potential contaminated area and the high-risk area of the land into multiple sampling units, and arrange a sampling point in each of the multiple sampling units;

[0022] Sampling points are densely distributed in each sampling unit in the area where the potential contaminated area of the land plot overlaps with the high-risk area of the land plot.

[0023] As another aspect of the present invention, obtaining the stratum structure and soil properties of the plot of soil to be explored and the surrounding areas thereof includes:

[0024] Collect engineering geological survey reports of the soil plot to be explored and its surrounding areas, and analyze the stratigraphic structure and soil properties of the plot and its surrounding areas based on the engineering geological survey reports.

[0025] As another aspect of the present invention, the abnormal soil distribution range includes the planar distribution information and the vertical distribution information of the abnormal soil.

[0026] As another aspect of the present invention, the sampling depth and position of the sampling points are obtained based on the resistivity measurement results of the land block and the adjustment of the stratum structure of the land block.

[0027] The beneficial effects of the present invention are:

[0028] (1) By combining the latest geophysical analysis, conductivity testing, and sensor testing methods, we will establish a precise survey and three-dimensional identification system that can be widely applied. At the same time, we will draw on the technical advantages of geological departments in physical and chemical exploration, rock and mineral testing, and engineering construction to apply them to the investigation of contaminated land, thereby improving the efficiency and accuracy of the investigation.

[0029] (2) Combined with the interpretation results of geophysical exploration, the soil or landfill with different physical properties in the region can be quickly located and identified, the plane distribution range can be delineated, and sampling can be carried out in areas with suspected contaminated soil or landfill, which can effectively avoid missing contaminated areas and solve the problem of "touching the edge" in pollution investigation; based on the geophysical exploration results and combined with the hydrogeological conditions, the sampling depth can be reasonably determined to solve the problem of difficulty in judging the sampling depth and avoid the problem of the sampling depth being unable to "probe and cover the bottom";

[0030] (3) Based on the results of geophysical exploration and the functional layout of the land, targeted sampling is carried out to achieve more comprehensive and accurate sampling, avoid the waste of a large number of invalid points, reduce workload and detection cycle, and lower survey costs. This method can produce significant economic and environmental benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 This is a flow chart of a sampling point arrangement method for geophysical exploration soil pollution status investigation provided by an embodiment of the present application;

[0032] Figure 2 This is a schematic diagram of a three-dimensional geological model in an embodiment of the present application;

[0033] Figure 3is a schematic diagram of landfill layers in potential contaminated areas and high-risk areas within the three-dimensional geological model in an embodiment of the present application;

[0034] Figure 4 Schematic diagram of the pond mud layer in the potential contaminated area and high-risk area within the three-dimensional geological model in the embodiment of the present application;

[0035] Figure 5 Schematic diagram of pond mud layer landfill in potential contaminated areas and high-risk areas within the three-dimensional geological model in the embodiment of the present application;

[0036] Figure 6 Schematic diagram of potential contamination range in potential contaminated areas and high-risk areas within the three-dimensional geological model in the embodiment of the present application;

[0037] Figure 7 This is the original functional layout diagram of the plot in the embodiment of this application;

[0038] Figure 8 This is a schematic diagram of the sampling layout points in the embodiment of the present application. DETAILED DESCRIPTION

[0039] To make the objectives, technical solutions, and advantages of the present invention more apparent, the present invention will be further described in detail below with reference to the accompanying drawings. It is apparent that the embodiments described are only some, not all, of the present invention. All other embodiments derived by persons of ordinary skill in the art based on the embodiments of the present invention without creative effort are intended to fall within the scope of protection of the present invention.

[0040] The terms used in the embodiments of the present invention are for the purpose of describing specific embodiments only and are not intended to limit the present invention. The singular forms "a," "an," "the," and "the" used in the embodiments of the present invention and the appended claims are also intended to include plural forms, and unless the context clearly indicates otherwise, "a plurality" generally includes at least two.

[0041] The embodiments of the present application describe a method for sampling points for geophysical exploration of soil pollution status, which is used to solve the problem proposed in the background art that the existing technology uses production-related areas in contaminated soil as high-risk areas for sampling points, which easily misses other contaminated areas in the contaminated soil, resulting in sampling results that are inconsistent with the actual pollution situation.

[0042] like Figure 1 As shown, a sampling point arrangement method for soil pollution status investigation in geophysical exploration recorded in an embodiment of the present application is implemented by S101-S105.

[0043] S101. Obtain the stratigraphic structure and soil properties of the plot of land where the soil to be explored is located and the surrounding areas of the plot.

[0044] In the embodiment of the present application, S101 includes:

[0045] Collect engineering geological survey reports of the soil plot to be explored and its surrounding areas, and analyze the stratigraphic structure and soil properties of the plot and its surrounding areas based on the engineering geological survey reports.

[0046] S102. Obtain the resistivity difference between the soil of the plot and the surrounding normal soil. When there is a difference between the two, measure the resistivity of the soil of the plot using a resistivity method.

[0047] In the embodiment of the present application, obtaining the resistivity difference between the soil of a plot and the surrounding normal soil includes:

[0048] Obtain characteristic pollutants related to the resistivity of the plot, set up soil test groups according to the characteristic pollutants, measure the soil resistivity of each soil test group, and obtain the difference between the soil resistivity of the plot soil and the soil resistivity of the normal soil around the plot to be tested. Based on the difference, preliminarily determine whether the plot contains landfill and obtain a preliminary judgment result. If the preliminary judgment result is that the plot contains landfill, proceed to the next step;

[0049] Among them, the relevant data of characteristic pollutants include the types of characteristic pollutants and the pollution equivalents of characteristic pollutants; the soil test groups include blank control group, one-time pollution equivalent test group, three-time pollution equivalent test group and five-time pollution equivalent test group; the blank control group is the normal soil around the plot soil, the one-time pollution equivalent test group is the plot soil, the three-time pollution equivalent test group is the plot soil with three times the pollution equivalent of the characteristic pollutants, and the five-time pollution equivalent test group is the plot soil with five times the pollution equivalent of the characteristic pollutants.

[0050] It can be understood that in the embodiment of the present application, the pollution equivalent of the characteristic pollutant is a pollution equivalent based on the risk screening value of the first category of land in the "Soil Environmental Quality Construction Land Soil Pollution Risk Control Standard (Trial)" (GB 36600-2018). This standard value is the current mandatory standard in soil pollution status surveys.

[0051] In the embodiment of the present application, the process of obtaining the one-fold pollution equivalent test group, the three-fold pollution equivalent test group and the five-fold pollution equivalent test group is as follows.

[0052] (1) Select normal soil from the surrounding area and conduct tests. The natural background value of its characteristic pollutants is used as the control value, and the moisture content is measured for future use.

[0053] (2) Preparation of test soil: Based on the Class I risk screening value of GB36600-2018, which is one pollution equivalent, test soils with 1, 3, and 5 times the pollution equivalent were prepared for testing.

[0054] (3) Before the test begins, sufficient deionized water solutions of characteristic pollutants are prepared at concentrations of 1, 3, and 5 times the pollution equivalent to meet the usage of one treatment for all replicate groups.

[0055] (4) Add appropriate amount of solution of each concentration to the artificial soil, supplement with deionized water so that the final moisture content of the soil reaches the moisture content level of the surrounding normal soil, mix well and place in the test container for use.

[0056] Optionally, in an embodiment of the present application, a preliminary judgment is made based on the difference as to whether the land parcel is landfilled, and the preliminary judgment result is obtained through a difference threshold. When the difference is greater than the difference threshold, the preliminary judgment result is that the land parcel is landfilled.

[0057] Optionally, the difference threshold may be 20%.

[0058] In the embodiment of the present application, the resistivity of the soil of a plot is measured by a resistivity method, including:

[0059] A plurality of measuring lines are set at equal intervals in the plot, a plurality of measuring points are set at equal intervals on the measuring lines, the resistivity of all measuring points is measured by the resistivity method, and the resistivity of all measuring points is determined as the resistivity of the soil in the plot.

[0060] Optionally, the spacing between the multiple measuring lines may be 10 m, and the spacing between the multiple measuring points may be 5 m.

[0061] S103. Determine a three-dimensional geological model of the land parcel that includes the abnormal soil distribution range based on the resistivity of the land parcel soil, extract edge coordinates of the abnormal soil distribution range in the three-dimensional geological model of the land parcel, and project the edge coordinates onto a map of the land parcel to obtain a potential contaminated area of the land parcel.

[0062] Optionally, in the implementation of the present application, the three-dimensional geological model of the land parcel including the abnormal soil distribution range is determined based on the resistivity of the soil of the land parcel, including:

[0063] The resistivity of the soil and the map of the plot are input into the 3D geological model to obtain a 3D geological model of the plot that includes the soil layer structure of the plot and shows the distribution range of abnormal soil. The map includes the longitudinal structural information of the soil layer of the plot.

[0064] The three-dimensional geological model obtained in the embodiment of this application is as follows Figure 2 As shown in the figure, the landfill layer in the 3D geological model is as follows Figure 3As shown. Since part of the landfill is exposed on the surface, it can be identified by the naked eye, but the scope and depth cannot be determined. For example, a garbage dump that appears to be only 10 square meters on the surface may be a trapezoid, and may expand to 20 square meters downwards, and the depth is also unpredictable. The method of the embodiment of the present application can identify the distribution of landfill solid waste and the depth of the landfill. In addition, landfill buried in vacant land, roads and other easily overlooked areas can also be identified by this method.

[0065] Furthermore, the pond mud layer in the 3D geological model is as follows Figure 4 As shown in the figure, the landfill in the pond mud layer is as follows Figure 5 As shown in the figure, the pond mud layer is the silt layer of a pond, river, or lake, in this case a pond. Generally speaking, the silt layer at the bottom of a natural body of water represents the original soil layer, undisturbed by human interference. This was the maximum sampling depth during the survey. As can be seen here, in reality, landfills have been embedded in the lower part of the pond mud layer, making it difficult to identify using traditional methods and easily overlooked.

[0066] In the embodiment of the present application, the abnormal soil distribution range includes the planar distribution information and the longitudinal distribution information of the abnormal soil.

[0067] S104. Based on the original functional layout map of the land parcel, obtain the high-risk area of the land parcel.

[0068] In the embodiment of the present application, S104 includes:

[0069] Based on the original functional layout map of the plot, the production-related areas in the plot are identified as high-risk areas of the plot through professional judgment.

[0070] Optionally, the production-related areas in the above-mentioned land plots include the original production areas and wastewater treatment facility areas.

[0071] In the embodiment of this application, the potential pollution range in the plot is as follows: Figure 6 As shown, the original functional layout of the plot is as follows Figure 7 shown.

[0072] S105. Sampling points are arranged in the potential contaminated area of the land parcel, sampling points are arranged in the high-risk area of the land parcel, and sampling points are arranged more densely in the area where the potential contaminated area of the land parcel overlaps with the high-risk area of the land parcel.

[0073] In the embodiment of the present application, S105 includes:

[0074] Divide the potential contaminated area and the high-risk area of the land into multiple sampling units, and arrange a sampling point in each of the multiple sampling units;

[0075] Sampling points are densely distributed in each sampling unit in the area where the potential contaminated area of the land plot overlaps with the high-risk area of the land plot.

[0076] Optionally, the sampling depth and position of the above-mentioned sampling points are obtained based on the resistivity measurement results of the land parcel and adjusted according to the stratum structure of the land parcel.

[0077] Optionally, the sampling unit in the embodiment of the present application is 40m*40m, and the sampling points are densely arranged so that at least two sampling points are arranged in each sampling unit.

Claims

1. A sampling method for geophysical exploration of soil pollution status, characterized in that: include: Obtain the stratigraphic structure and soil properties of the plot where the soil to be explored is located and its surrounding areas; Obtaining a resistivity difference between the soil of the plot and the surrounding normal soil. When there is a difference between the two, measuring the resistivity of the soil of the plot by a resistivity method; obtaining the resistivity difference between the soil of the plot and the surrounding normal soil includes: Obtain characteristic pollutants associated with the resistivity of the plot of land, set up soil test groups according to the characteristic pollutants, measure the soil resistivity of each soil test group, obtain the difference between the soil resistivity of the soil of the plot of land and the soil resistivity of normal soil surrounding the plot of land to be tested, and preliminarily determine whether the plot of landfill exists based on the difference, obtaining a preliminary determination result. If the preliminary determination result indicates that the plot of landfill exists, proceed to the next step; The relevant data of the characteristic pollutants include the types of the characteristic pollutants and the pollution equivalents of the characteristic pollutants; the soil test groups include a blank control group, a one-time pollution equivalent test group, a three-time pollution equivalent test group and a five-time pollution equivalent test group; the blank control group is normal soil around the soil of the plot, the one-time pollution equivalent test group is the soil of the plot, the three-time pollution equivalent test group is the plot soil with three times the pollution equivalent of the characteristic pollutant, and the five-time pollution equivalent test group is the plot soil with five times the pollution equivalent of the characteristic pollutant; Determining a three-dimensional geological model of the land parcel including an abnormal soil distribution range based on the resistivity of the soil of the land parcel, extracting edge coordinates of the abnormal soil distribution range in the three-dimensional geological model of the land parcel, and projecting the edge coordinates onto a map of the land parcel to obtain a potential contaminated area of the land parcel; Based on the original functional layout map of the land parcel, obtaining high-risk areas of the land parcel; Sampling points are arranged in the potential contaminated area of the land parcel, sampling points are arranged in the high-risk area of the land parcel, and sampling points are arranged more densely in the area where the potential contaminated area of the land parcel overlaps with the high-risk area of the land parcel.

2. The method for sampling points for geophysical exploration of soil pollution status according to claim 1, characterized in that: Measuring the resistivity of the soil of the plot by a resistivity method includes: A plurality of measuring lines are equidistantly set in the plot, a plurality of measuring points are equidistantly set on the measuring lines, the resistivity of all the measuring points is measured by the resistivity method, and the resistivity of all the measuring points is determined as the resistivity of the soil in the plot.

3. The method for sampling points for geophysical exploration of soil pollution status survey according to claim 1, characterized in that: The obtaining of high-risk areas of the land parcel based on the original functional layout map of the land parcel includes: Based on the original functional layout map of the land parcel, the production-related areas in the land parcel are determined as high-risk areas of the land parcel through professional judgment.

4. A method for sampling points for geophysical exploration of soil pollution status survey according to claim 3, characterized in that: The production-related areas in the land parcel include the original production area and the wastewater treatment facility area.

5. The method for sampling points for geophysical exploration of soil pollution status survey according to claim 1, characterized in that: The step of arranging sampling points in the potential contaminated area of the land parcel, arranging sampling points in the high-risk area of the land parcel, and accumulating the number of sampling points in the area where the potential contaminated area of the land parcel overlaps with the high-risk area of the land parcel includes: Dividing the potential contaminated area and the high-risk area of the land into a plurality of sampling units, and setting a sampling point in each of the plurality of sampling units; Sampling points are densely arranged in each sampling unit in the area where the potential contaminated area of the land plot overlaps with the high-risk area of the land plot.

6. The method for sampling points for geophysical exploration of soil pollution status according to claim 1, characterized in that: The acquisition of the stratum structure and soil properties of the plot of land where the soil to be explored is located and the surrounding areas of the plot includes: Collect engineering geological survey reports of the soil plot to be explored and its surrounding areas, and analyze the stratigraphic structure and soil properties of the plot and its surrounding areas based on the engineering geological survey reports.

7. The method for sampling points for geophysical exploration of soil pollution status according to claim 1, characterized in that: The abnormal soil distribution range includes the plane distribution information and the vertical distribution information of the abnormal soil.

8. The method for sampling points for geophysical exploration of soil pollution status according to claim 1, characterized in that: The sampling depth and position of the sampling points are obtained based on the resistivity measurement results of the land parcel and the adjustment of the stratum structure of the land parcel.

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