Industrial park soil and groundwater pollution early warning grade evaluation method

Abstract

This invention discloses a method for assessing the early warning level of soil and groundwater pollution in industrial parks, relating to the field of soil and groundwater pollution assessment. The method involves dividing the soil surface of the industrial park area S to be assessed into several horizontal grids with a step size λ, and dividing the vertical distance from the soil surface to the groundwater surface in area S into m layers with a step size ε. Soil characteristic parameters of the j-th soil layer are obtained. Emitted pollutants are classified into two categories: non-volatile pollutants and volatile pollutants. A geological model of the industrial park area S to be assessed is constructed based on the established parameters and soil characteristic parameters. The migration and transport mechanism of pollutants in the geological model is simulated to obtain the migration rate of different pollutants in each soil layer, thus acquiring pollutant emission information for area S. Based on the pollutant emission information and the obtained migration rate, the pollutant content of the j-th soil layer in the i-th grid at time t after pollutant emission is calculated.

Description

Technical Field

[0001] This 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 industrial parks. Background Technology

[0002] Currently, sampling methods are commonly used for soil and groundwater pollution monitoring. The sampling level and depth of soil sampling points are determined based on the vertical migration characteristics of pollutants in the soil and the depth of ground disturbance. In principle, multiple soil samples at different depths should be collected at each sampling point to determine the vertical distribution of pollutants. Groundwater monitoring wells are set up according to the groundwater flow direction and pollution requirements. The drilling depth of the monitoring wells can be determined based on the hydrogeological conditions of the site and the potential depth of pollution caused by the site.

[0003] According to Chinese patent document CN118095612B, a method for evaluating the early warning level of soil and groundwater pollution in industrial parks is proposed. This method uses a terrain simulation model to determine the infiltration distribution ratio and circumferential infiltration allocation ratio for each virtual area based on the initial conditions of the industrial park's soil and groundwater, including the horizontal distribution data of soil in each area and the distribution data of the elevation difference between soil in each area and the surrounding soil. Furthermore, based on the circumferential infiltration allocation ratio and the final pollutant situation corresponding to the original pollutants discharged, the infiltration amount in each direction along the circumference is obtained. Based on 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 pollutants from other areas in the infiltration intersection area, the final second content distribution data is obtained. The pollution early warning level and corresponding evaluation data are then obtained based on the second content distribution data.

[0004] According to relevant research, the main pollutants in industrial park soils include heavy metals and persistent organic pollutants (POPs). Different pollutants possess different physicochemical properties and exhibit varying migration and transformation behaviors in soil. For example, heavy metals (lead, cadmium, etc.) typically exist in soil as ions or complexes and are easily adsorbed by soil minerals; persistent organic pollutants such as polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs) have stable molecular structures, are difficult to degrade by microorganisms, and tend to accumulate and migrate in soil. Therefore, to accurately assess the pollution status of industrial park soil and groundwater, a comprehensive understanding of the types of pollutants present in the area and their existence states and transformation mechanisms in the soil is essential. However, the migration and transformation processes of pollutants in soil are influenced by complex physical, chemical, and biological processes. On the one hand, pollutants can migrate vertically within the soil profile through processes such as dissolution, diffusion, and infiltration, and may eventually enter the groundwater system. On the other hand, pollutants undergo chemical reactions such as adsorption, dissociation, and precipitation, altering their migration state in the soil. Existing technologies, when assessing the degree of soil pollution, do not consider the existence state and transformation mechanism of different pollutants in the soil, resulting in inaccurate pollutant content data and significant deviations between the assessment results and the actual situation. Therefore, we propose a method for assessing the early warning level of soil and groundwater pollution in industrial parks. Summary of the Invention

[0005] The main objective of this invention is to provide a method for assessing the early warning level of soil and groundwater pollution in industrial parks, which can effectively solve the problems in the background art.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0007] A method for assessing early warning levels of soil and groundwater pollution in industrial parks, comprising:

[0008] Let the industrial park area to be evaluated be 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 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. 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.

[0009] Pollutants are classified into two categories based on their volatility: non-volatile pollutants and volatile pollutants. A geological model of the industrial park area S to be evaluated is constructed based on the aforementioned settings and soil characteristic parameters. The migration and transport mechanisms of pollutants within the geological model are simulated to obtain the migration rates of different pollutants in each soil layer. These migration rates include vertical migration rates along the vertical direction. and horizontal migration rate along the horizontal direction ;in, This represents the vertical migration rate of non-volatile pollutants in the j-th soil layer of the i-th grid; This represents the vertical migration rate of volatile pollutants in the j-th soil layer of the i-th grid. This represents the horizontal migration rate of non-volatile pollutants in the j-th soil layer of the i-th grid; This represents the horizontal migration rate of volatile pollutants in the j-th soil layer of the i-th grid;

[0010] Obtain pollutant emission information for region S, including pollutant type information, emission amount information, and emission location information. Calculate the pollutant content of the j-th soil layer in the i-th grid at time t after pollutant emission based on the pollutant emission information and the obtained migration rate.

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

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

[0013] S11: Based on the emission amount information and the emission location information, determine the emission amount of the non-volatile pollutant in the first soil layer of the i-th grid. ;

[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 obtained emissions and Calculate the retention amount of the non-volatile pollutant in the first soil layer at time t after the pollutant is emitted. The calculation formula is: ;

[0016] S14: According to the formula The adsorption amount of the non-volatile pollutant in the first soil layer of the i-th grid was calculated, where, This represents the adsorption amount of non-volatile pollutants in the j-th soil layer of the i-th grid. It is expressed as the adsorption partition coefficient; Expressed as the equilibrium concentration of soil without volatile pollutants; The coefficients are constants, and ;

[0017] S15: Based on the obtained retention amount and adsorption capacity Based on the quantitative relationship, the retention of the non-volatile pollutant in the first soil layer of the i-th grid is classified as either completely retained in the first soil layer of the i-th grid or partially retained in the first soil layer of the i-th grid.

[0018] S16: Calculate the amount of emissions entering the second soil layer of the i-th grid when the portion of the non-volatile pollutant remains in the first soil layer of the i-th grid. The calculation formula is: ;

[0019] S17: Repeat steps S12-S15 above. This means that the non-volatile pollutant is completely contained within the q-th soil layer of the i-th grid, where q is an integer greater than 1, and when q > m, the non-volatile pollutant migrates to the groundwater layer.

[0020] When the emitted pollutant is a volatile pollutant, the calculation process for the pollutant content includes the following steps:

[0021] S21: Based on the emission amount information and the emission location information, determine the emission amount of the volatile pollutant in the first soil layer of the i-th grid. ;

[0022] S22: Calculate the migration amount of the volatile pollutant in the vertical and horizontal directions at time t after the pollutant is emitted. and and volatile amount ,in, In the formula, Let be the volatilization rate constant of the volatile pollutant, which is dimensionless; This is the vapor pressure of the volatile pollutant, in Pa. The adsorption coefficient of the soil for this volatile pollutant is expressed in L / kg. The water solubility of the volatile pollutant is expressed in mg / L. These are empirical constants;

[0023] S23: Based on the obtained emissions Migration and and volatile amount Calculate the retention amount of the volatile pollutant in the first soil layer at time t after the pollutant is emitted. The calculation formula is: In the formula, k is the volatile decay coefficient, and k∈(0,1];

[0024] S24: According to the formula Calculate the adsorption amount of the volatile pollutant in the first soil layer of the i-th grid, where, K represents the adsorption amount of volatile pollutants in the j-th soil layer of the i-th grid. d Represented as the adsorption partition coefficient; C p It is expressed as the equilibrium concentration of volatile pollutants in the soil; The coefficients are constants, and ;

[0025] S25: Based on the obtained retention amount Adsorption capacity and volatility Based on the quantitative relationship, the retention status of the volatile pollutant in the first soil layer of the i-th grid is classified as either completely retained in the first soil layer of the i-th grid or partially retained in the first soil layer of the i-th grid.

[0026] S26: Calculate the amount of emissions entering the second soil layer of the i-th grid when the volatile pollutant partially remains in the first soil layer of the i-th grid. The calculation formula is: ;

[0027] S27: Repeat steps S22-S25 above. This means that the volatile pollutant is completely contained within the q-th soil layer of the i-th grid. When q > m, the volatile pollutant migrates to the groundwater layer.

[0028] The classification principle for the retention of volatile pollutants in the first soil layer of grid i is as follows: when When, it is determined that the volatile pollutant is completely contained within the first soil layer of the i-th grid; when At that time, it was determined that the volatile pollutant was partially contained in the first soil layer of the i-th grid.

[0029] The volatility decay coefficient k is inversely proportional to the number of soil layers j, and satisfies the following formula: k=1 / j.

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

[0031] Compared with existing technologies, this method sets the industrial park area to be evaluated as S, divides the soil surface of area S into several horizontal grids with a step size λ, and sequentially numbers the i-th grid. It then divides the vertical distance from the soil surface to the groundwater surface in area S into m layers with a step size ε, obtains the soil characteristic parameters of the j-th soil layer, and classifies pollutants into non-volatile and volatile categories based on their volatility. A geological model of the industrial park area S is constructed based on the set parameters and soil characteristics. The migration and transport mechanism of pollutants in the geological model is simulated to obtain the migration rate of different pollutants in each soil layer. Pollutant emission information for area S is obtained, and the pollutant content of the j-th soil layer in the i-th grid at time t after pollutant emission is calculated based on the emission information and the obtained migration rate. The content of different pollutants in the soil is evaluated based on their existence state and transformation mechanism, which improves the accuracy of pollutant content data evaluation results. Attached Figure Description

[0032] Figure 1 This is a flowchart of a method for assessing early warning levels of soil and groundwater pollution in industrial parks according to the present invention.

[0033] Figure 2 A flowchart illustrating the calculation of data on the content of non-volatile pollutants in the soil layer;

[0034] Figure 3 This is a flowchart illustrating the calculation of data on the content of volatile pollutants in the soil layer. Detailed Implementation

[0035] The present invention will be further described below with reference to specific embodiments. The accompanying drawings are for illustrative purposes only and are schematic diagrams, not actual pictures. They should not be construed as limiting the present invention. In order to better illustrate the specific embodiments of the present invention, some parts in the drawings may be omitted, enlarged or reduced, and do not represent the actual product size.

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

[0037] Step 1: Define the industrial park area to be evaluated as S. Divide the soil surface in area S into several horizontal grids with a step size λ. Number the i-th grid 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. 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 moisture content, soil porosity, total soil bulk density, soil particle size distribution, soil saturation, soil void ratio, soil porosity, soil compressibility coefficient, soil compressibility index, and soil Poisson's ratio.

[0039] Step 2: Based on whether pollutants are volatile, they are classified into two categories: non-volatile pollutants and volatile pollutants. A geological model of the industrial park area S to be evaluated is constructed based on the established parameters and soil characteristics. The migration and transport mechanisms of pollutants within the geological model are simulated to obtain the migration rates of different pollutants in each soil layer. The migration rates include vertical migration rates along the vertical direction. and horizontal migration rate along the horizontal direction ;in, This represents the vertical migration rate of non-volatile pollutants in the j-th soil layer of the i-th grid; This represents the vertical migration rate of volatile pollutants in the j-th soil layer of the i-th grid. This represents the horizontal migration rate of non-volatile pollutants in the j-th soil layer of the i-th grid; This represents the horizontal migration rate of volatile pollutants in the j-th soil layer of the i-th grid;

[0040] Step 3: Obtain pollutant emission information for region S. The pollutant emission information includes pollutant type information, emission amount information, and emission location information. Calculate the pollutant content of the j-th soil layer in the i-th grid at time t after the pollutant emission based on the pollutant emission information and the obtained migration rate.

[0041] When the emitted pollutant is a non-volatile pollutant, the calculation process for the pollutant content includes the following steps:

[0042] S11: Based on the emission amount information and the emission location information, determine the emission amount of the non-volatile pollutant in the first soil layer of the i-th grid. ;

[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 obtained emissions and Calculate the retention amount of the non-volatile pollutant in the first soil layer at time t after the pollutant is emitted. The calculation formula is: ;

[0045] S14: According to the formula The adsorption amount of the non-volatile pollutant in the first soil layer of the i-th grid was calculated, where, This represents the adsorption amount of non-volatile pollutants in the j-th soil layer of the i-th grid. It is expressed as the adsorption partition coefficient; Expressed as the equilibrium concentration of soil without volatile pollutants; The coefficients are constants, and ;

[0046] S15: Based on the obtained retention amount and adsorption capacity Based on the quantitative relationship, the retention of the non-volatile pollutant in the first soil layer of the i-th grid is classified as either completely retained in the first soil layer of the i-th grid or partially retained in the first soil layer of the i-th grid.

[0047] The classification principle is: when When, it is determined that the non-volatile pollutant is completely contained within the first soil layer of the i-th grid; when At that time, it was determined that the portion of the non-volatile pollutant remained in the first soil layer of the i-th grid;

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

[0049] S17: Repeat steps S12-S15 above. This means that the non-volatile pollutant is completely contained within the q-th soil layer of the i-th grid, where q is an integer greater than 1, and when q > m, the non-volatile pollutant migrates to the groundwater layer.

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

[0051] When the emitted pollutant is a volatile pollutant, the calculation process for the pollutant content includes the following steps:

[0052] S21: Based on the emission amount information and the emission location information, determine the emission amount of the volatile pollutant in the first soil layer of the i-th grid. ;

[0053] S22: Calculate the migration amount of the volatile pollutant in the vertical and horizontal directions at time t after the pollutant is emitted. and and volatile amount ,in, In the formula, Let be the volatilization rate constant of the volatile pollutant, which is dimensionless; This is the vapor pressure of the volatile pollutant, in Pa. The adsorption coefficient of the soil for this volatile pollutant is expressed in L / kg. The water solubility of the volatile pollutant is expressed in mg / L. These are empirical constants;

[0054] S23: Based on the obtained emissions Migration and and volatile amount Calculate the retention amount of the volatile pollutant in the first soil layer at time t after the pollutant is emitted. The calculation formula is: In the formula, k is the volatile decay coefficient, and k∈(0,1];

[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, K represents the adsorption amount of volatile pollutants in the j-th soil layer of the i-th grid. d Represented as the adsorption partition coefficient; C p It is expressed as the equilibrium concentration of volatile pollutants in the soil; The coefficients are constants, and ;

[0056] S25: Based on the obtained retention amount Adsorption capacity and volatility Based on the quantitative relationship, the retention status of the volatile pollutant in the first soil layer of the i-th grid is classified as either completely retained in the first soil layer of the i-th grid or partially retained in the first soil layer of the i-th grid.

[0057] The classification principle is: when When, it is determined that the volatile pollutant is completely contained within the first soil layer of the i-th grid; when At that time, it was determined that the volatile pollutant was partially present in the first soil layer of the i-th grid;

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

[0059] S27: Repeat steps S22-S25 above. This means that the volatile pollutant is completely contained within the q-th soil layer of the i-th grid. When q > m, the volatile pollutant migrates to the groundwater layer.

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

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

[0062] It should be noted that when determining the amount of pollutant emitted in the j-th soil layer of the i-th grid, the horizontal migration between adjacent grids within region S should be taken into account. Therefore, the amount of horizontal migration is a result of taking into account both the amount of outward migration and the amount of migration from adjacent regions to this region.

[0063] After obtaining the content data of each pollutant in the soil layer, based on its content value and referring to relevant provisions such as GB 3660—2018 "Soil Environmental Quality Construction Land Soil Pollution Risk Control Standard (Trial)" and GB / T14848—2017 "Groundwater Quality Standard", the pollution level of the soil and groundwater in the park is assessed and warned according to the classification standards of the content of each polluted area for land with different uses and groundwater.

[0064] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of this invention is defined by the appended claims and their equivalents.

Claims

1. A method for assessing the early warning level of soil and groundwater pollution in industrial parks, characterized in that, include: Let the industrial park area to be evaluated be 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 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. 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. Pollutants are classified into two categories based on their volatility: non-volatile pollutants and volatile pollutants. A geological model of the industrial park area S to be evaluated is constructed based on the aforementioned settings and soil characteristic parameters. The migration and transport mechanisms of pollutants within the geological model are simulated to obtain the migration rates of different pollutants in each soil layer. These migration rates include vertical migration rates along the vertical direction. and horizontal migration rate along the horizontal direction ;in, This represents the vertical migration rate of non-volatile pollutants in the j-th soil layer of the i-th grid; This represents the vertical migration rate of volatile pollutants in the j-th soil layer of the i-th grid. This represents the horizontal migration rate of non-volatile pollutants in the j-th soil layer of the i-th grid; This represents the horizontal migration rate of volatile pollutants in the j-th soil layer of the i-th grid; Obtain pollutant emission information for region S, including pollutant type information, emission amount information, and emission location information. Calculate the pollutant content of the j-th soil layer in the i-th grid at time t after pollutant emission based on the pollutant emission information and the obtained migration rate. When the emitted pollutant is a non-volatile pollutant, the calculation process for the pollutant content includes the following steps: S11: Based on the emission amount information and the emission location information, determine the emission amount of the non-volatile pollutant in the first soil layer of the i-th grid. ; 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 obtained emissions and Calculate the retention amount of the non-volatile pollutant in the first soil layer at time t after the pollutant is emitted. The calculation formula is: ; S14: According to the formula The adsorption amount of the non-volatile pollutant in the first soil layer of the i-th grid was calculated, where, This represents the adsorption amount of non-volatile pollutants in the j-th soil layer of the i-th grid. It is expressed as the adsorption partition coefficient; Expressed as the equilibrium concentration of soil without volatile pollutants; The coefficients are constants, and ; S15: Based on the obtained retention amount and adsorption capacity Based on the quantitative relationship, the retention of the non-volatile pollutant in the first soil layer of the i-th grid is classified as either completely retained in the first soil layer of the i-th grid or partially retained in the first soil layer of the i-th grid. S16: Calculate the amount of emissions entering the second soil layer of the i-th grid when the portion of the non-volatile pollutant remains in the first soil layer of the i-th grid. The calculation formula is: ; S17: Repeat steps S12-S15 above. This means that the non-volatile pollutant is completely contained within the q-th soil layer of the i-th grid, where q is an integer greater than 1, and when q > m, the non-volatile pollutant migrates to the groundwater layer. When the emitted pollutant is a volatile pollutant, the calculation process for the pollutant content includes the following steps: S21: Based on the emission amount information and the emission location information, determine the emission amount of the volatile pollutant in the first soil layer of the i-th grid. ; S22: Calculate the migration amount of the volatile pollutant in the vertical and horizontal directions at time t after the pollutant is emitted. and and volatile amount ,in, In the formula, Let be the volatilization rate constant of the volatile pollutant, which is dimensionless; This is the vapor pressure of the volatile pollutant, in Pa. The adsorption coefficient of the soil for this volatile pollutant is expressed in L / kg. The water solubility of the volatile pollutant is expressed in mg / L. These are empirical constants; S23: Based on the obtained emissions Migration and and volatile amount Calculate the retention amount of the volatile pollutant in the first soil layer at time t after the pollutant is emitted. The calculation formula is: In the formula, k is the volatile decay 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, K represents the adsorption amount of volatile pollutants in the j-th soil layer of the i-th grid. d Represented as the adsorption partition coefficient; C p It is expressed as the equilibrium concentration of volatile pollutants in the soil; The coefficients are constants, and ; S25: Based on the obtained retention amount Adsorption capacity and volatility Based on the quantitative relationship, the retention status of the volatile pollutant in the first soil layer of the i-th grid is classified as either completely retained in the first soil layer of the i-th grid or partially retained in the first soil layer of the i-th grid. S26: Calculate the amount of emissions entering the second soil layer of the i-th grid when the volatile pollutant partially remains in the first soil layer of the i-th grid. The calculation formula is: ; S27: Repeat steps S22-S25 above. This means that the volatile pollutant is completely contained within the q-th soil layer of the i-th grid. When q > m, the volatile pollutant migrates to the groundwater layer.

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

3. The method for assessing the early warning level of soil and groundwater pollution in industrial parks according to claim 1, characterized in that, The volatility decay coefficient k is inversely proportional to the number of soil layers j, and satisfies the following formula: k=1 / j.

4. The method for assessing the early warning level of soil and groundwater pollution in industrial parks according to claim 1, characterized in that, The classification principle for the retention of non-volatile pollutants in the first soil layer of grid i is: when When, it is determined that the non-volatile pollutant is completely contained within the first soil layer of the i-th grid; when At that time, it was determined that the portion of the non-volatile pollutant remained in the first soil layer of the i-th grid.

5. The method for assessing the early warning level of soil and groundwater pollution in industrial parks according to claim 1, characterized in that, The classification principle for the retention of volatile pollutants in the first soil layer of grid i is as follows: when When, it is determined that the volatile pollutant is completely contained within the first soil layer of the i-th grid; when At that time, it was determined that the volatile pollutant was partially contained in the first soil layer of the i-th grid.

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