Industrial park soil and groundwater pollution early warning grade evaluation method

Abstract

The invention discloses an industrial park soil and groundwater pollution early warning grade evaluation method, and relates to the field of soil and groundwater pollution evaluation. The method comprises the following steps: dividing the soil surface in a to-be-evaluated industrial park area S into a plurality of grids in the horizontal direction at a step length lambda, equally dividing the distance from the soil surface in the area S to the underground water surface in the vertical direction into m layers at a step length epsilon, and obtaining soil characteristic parameters of a jth soil layer, the method comprises the following steps: classifying discharged pollutants into non-volatile pollutants and volatile pollutants, constructing a geologic model of a to-be-evaluated industrial park area S according to setting and soil characteristic parameters, carrying out analogue simulation on a migration transmission mechanism of the pollutants in the geologic model, obtaining migration rates of different pollutants in each soil layer, and carrying out evaluation on the migration rates of the pollutants in the to-be-evaluated industrial park area S according to the migration rates of the pollutants in the to-be-evaluated industrial park area S; and acquiring pollutant discharge information of the area S, and calculating the pollutant content of the jth soil layer of the ith grid at the t moment after pollutant discharge according to the pollutant discharge information and the acquired migration rate.

Description

Technical Field

[0001] The invention relates to the field of soil and groundwater pollution assessment, and in particular to a method for assessing the early warning level of soil and groundwater pollution in an industrial park. Background Art

[0002] At present, the sampling method is usually used to monitor soil and groundwater pollution. The sampling level and depth of the soil sampling point are determined according to the vertical migration characteristics of pollutants in the soil and the depth of ground disturbance. In principle, each sampling point needs to collect more than one soil sample at different depths to determine the vertical distribution of pollutants. Groundwater monitoring wells are set up on site according to the requirements of groundwater flow and pollution. The drilling depth of the monitoring well can be determined according to the hydrogeological conditions of the site, the depth of pollution that may be caused by the site, etc.

[0003] For example, according to a method for evaluating the pollution warning level of soil and groundwater in an industrial park disclosed in a Chinese patent document with the announcement number CN118095612B, the method determines the corresponding infiltration distribution ratio of each virtual area and the circumferential infiltration apportionment ratio of each virtual area according to the initial conditions of the soil and groundwater in the industrial park, including the distribution data of the soil in each area in the horizontal direction, and the distribution data of the terrain height difference of the soil in each area relative to the soil in the surrounding area under the terrain simulation model. And according to the circumferential infiltration apportionment ratio and the final pollutant corresponding to the discharged original pollutant, the infiltration amount downward in all directions along the circumference is obtained. According to the infiltration amount, the first content distribution data along each infiltration direction is accurately determined under simulation. And based on the combination of the first content distribution data and other regional pollutants in the infiltration interlaced area, the final second content distribution data is obtained, and the pollution warning level and the corresponding evaluation data are obtained according to the second content distribution data.

[0004] According to the results of relevant investigations and studies, the main pollutants in the soil of industrial parks include heavy metals, persistent organic pollutants, etc. Different pollutants have different physical and chemical properties and different migration and transformation behaviors in the soil. For example, heavy metals (lead, cadmium, etc.) usually exist in the soil in the form of ions or complexes and are easily adsorbed by soil minerals; persistent organic matter such as polycyclic aromatic hydrocarbons and polychlorinated biphenyls has a stable molecular structure, is difficult to be degraded by microorganisms, and is easy to enrich and migrate in the soil. Therefore, in order to accurately assess the pollution of park soil and groundwater under the action of pollutants, it is first necessary to have a comprehensive understanding of the types of pollutants in the area and the existence status and transformation mechanism of different pollutants in the soil. However, the migration and transformation process of pollutants in the soil is affected by complex physical, chemical and biological processes. On the one hand, pollutants can migrate vertically in the soil profile through processes such as dissolution, diffusion, and infiltration, and may eventually enter the groundwater system. On the other hand, pollutants will undergo chemical reactions such as adsorption, dissociation, and precipitation, changing their migration state in the soil. In the existing technology, when evaluating the degree of soil pollution, the existence state and transformation mechanism of different pollutants in the soil are not taken into account, resulting in inaccurate pollutant content data obtained, which makes the evaluation results deviate greatly from the actual situation. To this end, we propose an industrial park soil and groundwater pollution warning level assessment method. Summary of the invention

[0005] The main purpose of the present invention is to provide a method for evaluating the early warning level of soil and groundwater pollution in an industrial park, which can effectively solve the problems in the background technology.

[0006] In order to achieve the above object, the technical solution adopted by the present invention is:

[0007] A method for assessing the early warning level of soil and groundwater pollution in an industrial park, comprising:

[0008] The industrial park area to be evaluated is set as S, and the soil surface in area S is divided into several grids in the horizontal direction with a step size of λ. The i-th grid is numbered in sequence in a certain order, and the distance from the soil surface to the groundwater surface in area S is divided into m layers in the vertical direction with a step size of ε. The soil characteristic parameters of the j-th soil layer are obtained, where i = 1, 2, ..., n; n is the total number of grids, j = 1, 2, ..., m; and when j = 1, it is the soil surface layer;

[0009] According to whether the pollutants are volatile, they are classified into two categories: non-volatile pollutants and volatile pollutants. According to the settings and the soil characteristic parameters, a geological model of the industrial park area S to be evaluated is constructed, and the migration and transmission mechanism of pollutants in the geological model is simulated to obtain the migration rate of different pollutants in each soil layer. The migration rate includes the vertical migration rate in the vertical direction. and the horizontal migration rate in the horizontal direction in, It is expressed as the vertical migration rate of non-volatile pollutants in the jth soil layer; It is expressed as the vertical migration rate of volatile pollutants in the jth soil layer; It is expressed as the horizontal migration rate of non-volatile pollutants in the jth soil layer; It is expressed as the horizontal migration rate of volatile pollutants in the jth soil layer;

[0010] The pollutant emission information of area S is obtained, wherein the pollutant emission information includes pollutant type information, emission amount information, and emission location point information. The pollutant content of the jth soil layer of the i-th grid at time t after the pollutant is discharged is calculated based on the pollutant emission information and the obtained migration rate.

[0011] The soil characteristic parameters include soil pH, soil specific gravity, soil water content, soil porosity, soil total bulk density, soil particle size distribution, soil saturation, soil void ratio, soil porosity, soil compression coefficient, soil compression index, and soil Poisson's ratio.

[0012] When the type of pollutant emitted is non-volatile pollutant, the calculation process of the pollutant content includes the following steps:

[0013] S11: Determine the emission amount of the non-volatile pollutant in the first soil layer of the i-th grid according to the emission amount information and the emission location point information

[0014] S12: Calculate the migration amount of the non-volatile pollutant in the vertical and horizontal directions at time t after the pollutant is emitted. and in,

[0015] S13: Based on the emissions obtained and Calculate the retention of the non-volatile pollutant in the first soil layer at time t after the pollutant is discharged The calculation formula is: 1 1 =Em 1 1 -(Mv 1 1 +Mv 1 2 );

[0016] S14: According to the formula Calculate the adsorption amount of the non-volatile pollutant in the first soil layer of the i-th grid, where: It is expressed as the adsorption amount of non-volatile pollutants in the jth soil layer of the i-th grid, K d Expressed as adsorption distribution coefficient; C p It is expressed as the equilibrium concentration of the soil without volatile pollutants; is a constant coefficient, and

[0017] S15: Based on the obtained retention volume H 1 And adsorption According to the quantitative relationship of , the retention of the non-volatile pollutant in the first soil layer of the i-th grid is classified into completely retained in the first soil layer of the i-th grid and partially retained in the first soil layer of the i-th grid;

[0018] The classification principle is: When , it is determined that the non-volatile pollutant is completely retained in the first soil layer of the i-th grid; when , it is determined that the non-volatile pollutant portion remains in the first soil layer of the i-th grid;

[0019] S16: Calculate the emission amount entering the second soil layer of the i-th grid when the non-volatile pollutant portion remains in the first soil layer of the i-th grid The calculation formula is:

[0020] S17: Repeat the above steps S12-S15 until That is, the non-volatile pollutant completely remains in the qth soil layer of the ith grid, wherein q is an integer greater than 1, and when q>m, the non-volatile pollutant migrates to the groundwater layer.

[0021] When the type of pollutants emitted is volatile pollutants, the calculation process of the pollutant content includes the following steps:

[0022] S21: Determine the emission amount of the volatile pollutant in the first soil layer of the i-th grid according to the emission amount information and the emission location point information

[0023] S22: Calculate the vertical and horizontal migration of the volatile pollutant at time t after the pollutant is emitted. and And the volatility Vo, where Vo=K v ×t; where K v is the volatilization rate constant of the volatile pollutant; P vp is the vapor pressure of the volatile pollutant; K ∝is the adsorption coefficient of the soil to the volatile pollutant; Sw is the water solubility of the volatile pollutant;

[0024] S23: Based on the emissions obtained Migration amount The retention amount of the volatile pollutant in the first soil layer at time t after the pollutant is discharged is calculated by using the volatilization amount Vo The calculation formula is: Where k is the volatilization attenuation coefficient, and k∈(0,1]; the volatilization attenuation coefficient k is inversely proportional to the number of soil layers j, and satisfies the following formula: k=1 / j;

[0025] S24: According to the formula Calculate the adsorption amount of the volatile pollutant in the first soil layer of the i-th grid, where: It is expressed as the adsorption amount of volatile pollutants in the jth soil layer of the i-th grid, K d Expressed as adsorption distribution coefficient; C p It is expressed as the equilibrium concentration of volatile pollutants in the soil; is a constant coefficient, and

[0026] S25: Based on the retention volume obtained Adsorption and the quantitative relationship between the volatilization amount Vo, classifying the retention of the volatile pollutant in the first soil layer of the i-th grid into completely retained in the first soil layer of the i-th grid and partially retained in the first soil layer of the i-th grid;

[0027] The classification principle is: When , it is determined that the volatile pollutants are completely retained in the first soil layer of the i-th grid; when When , it is determined that the volatile pollutants are partially retained in the first soil layer of the i-th grid;

[0028] S26: Calculate the emission amount entering the second soil layer of the i-th grid when the volatile pollutant part remains in the first soil layer of the i-th grid The calculation formula is:

[0029] S27: Repeat the above steps S22-S25 until That is, the volatile pollutants are completely retained in the qth soil layer of the i-th grid. When q>m, the volatile pollutants migrate to the groundwater layer.

[0030] The present invention has the following beneficial effects:

[0031] Compared with the prior art, the industrial park area to be evaluated is set as S, the soil surface in area S is divided into several grids in the horizontal direction with a step size λ, the i-th grid is numbered in sequence in a certain order, and the distance from the soil surface to the groundwater surface in area S in the vertical direction is divided into m layers with a step size ε, the soil characteristic parameters of the j-th soil layer are obtained, and the pollutants are classified into two categories of non-volatile pollutants and volatile pollutants according to whether they are volatile. A geological model of the industrial park area S to be evaluated is constructed according to the setting and soil characteristic parameters, the migration and transmission mechanism of pollutants in the geological model is simulated, the migration rate of different pollutants in each soil layer is obtained, the pollutant emission information of area S is obtained, and the pollutant content of the j-th soil layer of the i-th grid at time t after the pollutant is discharged is calculated according to the pollutant emission information and the obtained migration rate, and the content of different pollutants in the soil is evaluated based on the existence state and transformation mechanism of different pollutants in the soil, which can improve the accuracy of the pollutant content data evaluation results. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 This is a flow chart of a method for assessing early warning levels of soil and groundwater pollution in an industrial park according to the present invention;

[0033] Figure 2 The flow chart for calculating the content of non-volatile pollutants in the soil layer;

[0034] Figure 3 This is a flow chart for calculating the content of volatile pollutants in the soil layer. DETAILED DESCRIPTION

[0035] The present invention will be further described below in conjunction with specific implementation methods, wherein the accompanying drawings are only used for exemplary descriptions and represent only schematic diagrams rather than actual drawings, and should not be understood as limiting the present invention. In order to better illustrate the specific implementation methods of the present invention, some parts of the accompanying drawings may be omitted, enlarged or reduced, and do not represent the size of the actual product.

[0036] The specific implementation process of the technical solution of the present invention includes the following steps:

[0037] Step 1: Set the area of ​​the industrial park to be evaluated as S, divide the soil surface in area S into several grids in the horizontal direction with a step size λ, number the i-th grid in sequence in a certain order, divide the vertical distance from the soil surface to the groundwater surface in area S into m layers with a step size ε, and obtain the soil characteristic parameters of the j-th soil layer, where i = 1, 2, ..., n; n is the total number of grids, j = 1, 2, ..., m; and when j = 1, it is the soil surface layer;

[0038] Soil characteristic parameters include soil pH, soil specific gravity, soil water content, soil porosity, soil total bulk density, soil particle size distribution, soil saturation, soil void ratio, soil porosity, soil compression coefficient, soil compression index, and soil Poisson's ratio.

[0039] Step 2: Classify pollutants into non-volatile pollutants and volatile pollutants according to whether they are volatile or not. Construct a geological model of the industrial park area S to be evaluated based on the settings and soil characteristic parameters, simulate the migration and transmission mechanism of pollutants in the geological model, and obtain the migration rate of different pollutants in each soil layer. The migration rate includes the vertical migration rate v in the vertical direction. 1 j1 、v j 2 1 and the horizontal migration rate in the horizontal direction in, It is expressed as the vertical migration rate of non-volatile pollutants in the jth soil layer; It is expressed as the vertical migration rate of volatile pollutants in the jth soil layer; It is expressed as the horizontal migration rate of non-volatile pollutants in the jth soil layer; It is expressed as the horizontal migration rate of volatile pollutants in the jth soil layer;

[0040] Step 3: Obtain pollutant emission information of area S, which includes pollutant type information, emission amount information, and emission location information. Calculate the pollutant content of the jth soil layer of the i-th grid at time t after the pollutant is discharged based on the pollutant emission information and the obtained migration rate;

[0041] Among them, when the type of pollutant emitted is only one non-volatile pollutant, the calculation process of the pollutant content includes the following steps:

[0042] S11: Determine the emission amount of the non-volatile pollutant in the first soil layer of the i-th grid according to the emission amount information and emission location point information

[0043] S12: Calculate the migration amount of the non-volatile pollutant in the vertical and horizontal directions at time t after the pollutant is emitted. and in,

[0044] S13: Based on the emissions obtained and Calculate the retention of the non-volatile pollutant in the first soil layer at time t after the pollutant is discharged The calculation formula is:

[0045] S14: According to the formula Calculate the adsorption amount of the non-volatile pollutant in the first soil layer of the i-th grid, where: It is expressed as the adsorption amount of non-volatile pollutants in the jth soil layer of the i-th grid, K d Expressed as adsorption distribution coefficient; C p It is expressed as the equilibrium concentration of the soil without volatile pollutants; is a constant coefficient, and

[0046] S15: Based on the obtained retention volume H 1 And adsorption According to the quantitative relationship of , the retention of the non-volatile pollutant in the first soil layer of the i-th grid is classified into completely retained in the first soil layer of the i-th grid and partially retained in the first soil layer of the i-th grid;

[0047] The classification principle is: When , it is determined that the non-volatile pollutant is completely retained in the first soil layer of the i-th grid; when , it is determined that the non-volatile pollutant portion remains in the first soil layer of the i-th grid;

[0048] S16: Calculate the emission amount entering the second soil layer of the i-th grid when the non-volatile pollutant portion remains in the first soil layer of the i-th grid The calculation formula is:

[0049] S17: Repeat the above steps S12-S15 until That is, the non-volatile pollutant completely remains in the qth soil layer of the ith grid, wherein q is an integer greater than 1, and when q>m, the non-volatile pollutant migrates to the groundwater layer.

[0050] When the pollutant types emitted contain multiple non-volatile pollutants, the content data of one of the pollutants is first calculated according to the calculation process S11-S17, and then the above steps are repeated to calculate the remaining types of pollutants, which will not be repeated here;

[0051] When only one type of pollutant is volatile, the calculation process of the pollutant content includes the following steps:

[0052] S21: Determine the emission amount of the volatile pollutant in the first soil layer of the i-th grid according to the emission amount information and emission location point information

[0053] S22: Calculate the vertical and horizontal migration of the volatile pollutant at time t after the pollutant is emitted. and And the volatility Vo, where Vo=K v ×t; where K v is the volatilization rate constant of the volatile pollutant; P vp is the vapor pressure of the volatile pollutant; K ∝ is the adsorption coefficient of the soil to the volatile pollutant; Sw is the water solubility of the volatile pollutant;

[0054] S23: Based on the emissions obtained and Vo to calculate the retention H of the volatile pollutant in the first soil layer at time t after the pollutant is discharged 1 2 , the calculation formula is: Where k is the volatilization attenuation coefficient, and k∈(0,1]; the volatilization attenuation coefficient k is inversely proportional to the number of soil layers j, and satisfies the following formula: k=1 / j;

[0055] S24: According to the formula Calculate the adsorption amount of the volatile pollutant in the first soil layer of the i-th grid, where: It is expressed as the adsorption amount of volatile pollutants in the jth soil layer of the i-th grid, K d Expressed as adsorption distribution coefficient; C p It is expressed as the equilibrium concentration of volatile pollutants in the soil; is a constant coefficient, and

[0056] S25: Based on the retention volume obtained Adsorption and the quantitative relationship between the volatilization amount Vo, classifying the retention of the volatile pollutant in the first soil layer of the i-th grid into completely retained in the first soil layer of the i-th grid and partially retained in the first soil layer of the i-th grid;

[0057] The classification principle is: When , it is determined that the volatile pollutants are completely retained in the first soil layer of the i-th grid; when When , it is determined that the volatile pollutants are partially retained in the first soil layer of the i-th grid;

[0058] S26: Calculate the emission amount entering the second soil layer of the i-th grid when the volatile pollutant part remains in the first soil layer of the i-th grid The calculation formula is:

[0059] S27: Repeat the above steps S22-S25 until That is, the volatile pollutants are completely retained in the qth soil layer of the i-th grid. When q>m, the volatile pollutants migrate to the groundwater layer.

[0060] When the pollutant types emitted contain multiple volatile pollutants, the content data of one of the pollutants is first calculated according to the calculation process S21-S27, and then the above steps are repeated to calculate the remaining types of pollutants, which will not be repeated here;

[0061] When the types of pollutants emitted contain both volatile pollutants and non-volatile pollutants, the content data of one type of non-volatile pollutants is first calculated according to the calculation process S11-S17, and then the above steps are repeated to calculate the remaining types of non-volatile pollutants. The content data of one type of volatile pollutants is first calculated according to the calculation process S21-S27, and then the above steps are repeated to calculate the remaining types of volatile pollutants. The calculation process of each type of pollutant is relatively independent.

[0062] It should be noted that when determining the emission of pollutants in the jth soil layer of the ith grid, the horizontal migration effect between adjacent grids in area S should be comprehensively considered. Therefore, the horizontal migration amount is the result of comprehensively considering the outward migration amount and the migration amount from adjacent areas to this area.

[0063] After obtaining the content data of each pollutant in the soil layer, based on its content value, refer to GB 3660-2018 "Soil Environmental Quality Construction Land Soil Pollution Risk Control Standard (Trial)" and GB / T14848-2017 "Groundwater Quality Standard" and other relevant regulations, and classify the content of each pollution area for land and groundwater of different use natures, and evaluate and warn the pollution degree of the park's soil and groundwater.

[0064] The above shows and describes the basic principles and main features of the present invention and the advantages of the present invention. It should be understood by those skilled in the art that the present invention is not limited to the above embodiments. The above embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, which fall within the scope of the present invention to be protected. The scope of protection of the present invention is defined by the attached claims and their equivalents.

Claims

1. A method for assessing the early warning level of soil and groundwater pollution in an industrial park, characterized in that: include: The industrial park area to be evaluated is set as S, and the soil surface in area S is divided into several grids in the horizontal direction with a step size of λ. The i-th grid is numbered in sequence in a certain order, and the distance from the soil surface to the groundwater surface in area S is divided into m layers in the vertical direction with a step size of ε. The soil characteristic parameters of the j-th soil layer are obtained, where i = 1, 2, ..., n; n is the total number of grids, j = 1, 2, ..., m; and when j = 1, it is the soil surface layer; According to whether the pollutants are volatile, they are classified into two categories: non-volatile pollutants and volatile pollutants. According to the settings and the soil characteristic parameters, a geological model of the industrial park area S to be evaluated is constructed, and the migration and transmission mechanism of pollutants in the geological model is simulated to obtain the migration rate of different pollutants in each soil layer. The migration rate includes the vertical migration rate in the vertical direction. and the horizontal migration rate in the horizontal direction in, It is expressed as the vertical migration rate of non-volatile pollutants in the jth soil layer; It is expressed as the vertical migration rate of volatile pollutants in the jth soil layer; It is expressed as the horizontal migration rate of non-volatile pollutants in the jth soil layer; It is expressed as the horizontal migration rate of volatile pollutants in the jth soil layer; The pollutant emission information of area S is obtained, wherein the pollutant emission information includes pollutant type information, emission amount information, and emission location point information. The pollutant content of the jth soil layer of the i-th grid at time t after the pollutant is discharged is calculated based on the pollutant emission information and the obtained migration rate.

2. The method for evaluating the early warning level of soil and groundwater pollution in an industrial park according to claim 1 is characterized in that: The soil characteristic parameters include soil pH, soil specific gravity, soil water content, soil porosity, soil total bulk density, soil particle size distribution, soil saturation, soil void ratio, soil porosity, soil compression coefficient, soil compression index, and soil Poisson's ratio.

3. The method for evaluating the early warning level of soil and groundwater pollution in an industrial park according to claim 1 is characterized in that: When the type of pollutant emitted is non-volatile pollutant, the calculation process of the pollutant content includes the following steps: S11: Determine the emission amount of the non-volatile pollutant in the first soil layer of the i-th grid according to the emission amount information and the emission location point information S12: Calculate the migration amount of the non-volatile pollutant in the vertical and horizontal directions at time t after the pollutant is emitted. and in, S13: Based on the emissions obtained and Calculate the retention of the non-volatile pollutant in the first soil layer at time t after the pollutant is discharged The calculation formula is: S14: According to the formula Calculate the adsorption amount of the non-volatile pollutant in the first soil layer of the i-th grid, where: It is expressed as the adsorption amount of non-volatile pollutants in the jth soil layer of the i-th grid, K d Expressed as adsorption distribution coefficient; C p It is expressed as the equilibrium concentration of the soil without volatile pollutants; is a constant coefficient, and S15: Based on the obtained retention volume H1 and adsorption volume According to the quantitative relationship of , the retention of the non-volatile pollutant in the first soil layer of the i-th grid is classified into completely retained in the first soil layer of the i-th grid and partially retained in the first soil layer of the i-th grid; S16: Calculate the emission amount entering the second soil layer of the i-th grid when the non-volatile pollutant portion remains in the first soil layer of the i-th grid The calculation formula is: S17: Repeat the above steps S12-S15 until That is, the non-volatile pollutant completely remains in the qth soil layer of the ith grid, wherein q is an integer greater than 1, and when q>m, the non-volatile pollutant migrates to the groundwater layer.

4. The method for evaluating the early warning level of soil and groundwater pollution in an industrial park according to claim 1, characterized in that: When the type of pollutants emitted is volatile pollutants, the calculation process of the pollutant content includes the following steps: S21: Determine the emission amount of the volatile pollutant in the first soil layer of the i-th grid according to the emission amount information and the emission location point information S22: Calculate the vertical and horizontal migration of the volatile pollutant at time t after the pollutant is emitted. and And the volatility Vo, where Vo=K v ×t; where K v is the volatilization rate constant of the volatile pollutant; P vp is the vapor pressure of the volatile pollutant; K ∝ is the adsorption coefficient of the soil to the volatile pollutant; Sw is the water solubility of the volatile pollutant; S23: Based on the emissions obtained Migration amount The retention amount of the volatile pollutant in the first soil layer at time t after the pollutant is discharged is calculated by using the volatilization amount Vo The calculation formula is: Where k is the volatility attenuation coefficient, and k∈(0,1]; S24: According to the formula Calculate the adsorption amount of the volatile pollutant in the first soil layer of the i-th grid, where: It is expressed as the adsorption amount of volatile pollutants in the jth soil layer of the i-th grid, K d Expressed as adsorption distribution coefficient; C p It is expressed as the equilibrium concentration of volatile pollutants in the soil; is a constant coefficient, and S25: Based on the retention volume obtained Adsorption and the quantitative relationship between the volatilization amount Vo, classifying the retention of the volatile pollutant in the first soil layer of the i-th grid into completely retained in the first soil layer of the i-th grid and partially retained in the first soil layer of the i-th grid; S26: Calculate the emission amount entering the second soil layer of the i-th grid when the volatile pollutant part remains in the first soil layer of the i-th grid The calculation formula is: S27: Repeat the above steps S22-S25 until That is, the volatile pollutants are completely retained in the qth soil layer of the i-th grid. When q>m, the volatile pollutants migrate to the groundwater layer.

5. The method for evaluating the early warning level of soil and groundwater pollution in an industrial park according to claim 4 is characterized in that: The volatilization attenuation coefficient k is inversely proportional to the number of soil layers j and satisfies the following formula: k = 1 / j.

6. The method for evaluating the early warning level of soil and groundwater pollution in an industrial park according to claim 3 is characterized in that: The classification principle for the retention of non-volatile pollutants in the first soil layer of the i-th grid is: When , it is determined that the non-volatile pollutant is completely retained in the first soil layer of the i-th grid; when , it is determined that the non-volatile pollutant portion remains in the first soil layer of the i-th grid.

7. The method for evaluating the early warning level of soil and groundwater pollution in an industrial park according to claim 4 is characterized in that: The classification principle for the retention of volatile pollutants in the first soil layer of the i-th grid is: When , it is determined that the volatile pollutants are completely retained in the first soil layer of the i-th grid; when , it is determined that part of the volatile pollutants remain in the first soil layer of the i-th grid.

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