Underground water pollution source analysis and risk assessment method and system

Abstract

The invention relates to the technical field of underground water, in particular to an underground water pollution source analysis and risk assessment method and system.The method comprises the following steps that monitoring points are arranged in a potential underground water affected area, water samples are collected, and organic pollutants, heavy metal content and microbial metabolites in the water samples are analyzed; collecting the characteristic spectrum data of the pollutants, and carrying out normalization processing to obtain a pollutant spectrum characteristic set; according to the method, the organic pollutants, the heavy metals and the microbial metabolites in the water sample are analyzed by using a liquid chromatography-mass spectrometry technology, accurate detection of the trace pollutants is realized, the data standardization level is improved through normalization processing of the pollutant spectral feature set, cross-regional data comparison and analysis are facilitated, and the detection accuracy is improved. The pollution source can be quickly identified through automatic data comparison, errors are reduced, the response speed is increased, and detailed analysis of spatial distribution data provides a comprehensive pollution diffusion picture, so that risk assessment is more comprehensive.

Description

Technical Field

[0001] The present invention relates to the field of groundwater technology, and in particular to a groundwater pollution source analysis and risk assessment method and system. Background Art

[0002] The field of groundwater technology involves many aspects such as groundwater exploration, extraction, management and protection. This field focuses on the sustainability and sustainable use of groundwater resources, especially in the context of increasingly tight global water resources. Technologies include groundwater monitoring, pollution control and remediation technologies, as well as the rational allocation and utilization of water resources. The groundwater field covers scientific research on groundwater systems, such as hydrogeology, hydrodynamics, and the migration and distribution patterns of pollutants in groundwater environments.

[0003] Among them, groundwater pollution source analysis and risk assessment methods focus on identifying and assessing groundwater pollution risks and their sources, including the use of various geological, chemical and biological techniques to analyze groundwater samples, determine the types and concentrations of pollutants, and thus reveal the sources of pollution and transmission paths. The main purpose is to formulate effective groundwater protection and restoration measures, prevent further pollution, and protect public health and ecological safety. It can help decision makers formulate scientific management policies and response strategies.

[0004] Existing technologies are limited in their ability to rapidly identify and accurately measure pollutants due to the sensitivity of equipment and the limitations of analytical methods, resulting in the inability to effectively cover a wide range of pollutant types. The lack of sufficient real-time updates and high-precision analysis capabilities has delayed pollution assessments and response strategies, exacerbating the problem of groundwater pollution in the context of increasingly tight water resources. The lack of efficient real-time monitoring and automated analysis is particularly critical in the early warning and rapid response of groundwater pollution incidents, limiting the timeliness and effectiveness of groundwater protection measures and easily increasing environmental and public health risks. Summary of the invention

[0005] The purpose of the present invention is to solve the shortcomings of the prior art and to propose a method and system for groundwater pollution source analysis and risk assessment.

[0006] In order to achieve the above-mentioned purpose, the present invention adopts the following technical scheme: a method for groundwater pollution source analysis and risk assessment, comprising the following steps: S1: Set up monitoring points in potential groundwater-affected areas, collect water samples, analyze organic pollutants, heavy metal content and microbial metabolites in water samples, collect characteristic spectral data of pollutants, perform normalization processing, and obtain pollutant spectral feature sets; S2: Based on the pollutant spectral feature set, identify the types of pollutants associated with the groundwater pollution source, and perform numerical analysis on the pollutant concentration at each monitoring point to determine the pollutant concentration at each monitoring point and obtain pollutant concentration distribution data; S3: calling the pollutant concentration distribution data, combining the geological background data of the groundwater pollution source, analyzing the groundwater flow characteristics, analyzing the hydraulic parameters that affect the pollution diffusion, calculating the migration rate and diffusion radius of the pollutants, and obtaining the pollution diffusion dynamic index; S4: Based on the pollution diffusion dynamic indicators, the reverse trajectory of pollutant flow in different areas is analyzed, the location of potential pollution sources is evaluated, and the pollutant concentration data of the pollution sources and their surrounding areas are compared to screen pollution source points with prominent pollution concentrations to obtain the pollution source assessment index.

[0007] The improvements of the present invention are that the pollutant spectral feature set includes spectral peak, characteristic wavelength, and metabolite identification; the pollutant concentration distribution data includes pollution intensity, pollution range, and key monitoring points; the pollution diffusion dynamic indicators include migration path, impact area, and dynamic change rate; the pollution source assessment index includes source activity, impact intensity, and risk potential.

[0008] The present invention is improved in that the steps of acquiring the pollutant spectral feature set are specifically as follows: S111: Set up monitoring points in potential groundwater-affected areas, collect water samples, detect organic pollutants, heavy metal content and microbial metabolites in water samples by liquid chromatography-mass spectrometry, extract spectral data of each type of pollutant, normalize the spectral data, and obtain normalized spectral data; S112: Based on the normalized spectral data, analyze the spectral characteristics of the pollutant, calculate the peak position, absorption intensity and half-peak width, using the formula: ; Get the spectral characteristic values ​​of the pollutants, where: Representative The spectral characteristic values ​​of the pollutants are Representative The pollutants in The peak position at wavelength, Represents all pollutants in The average value of the peak position at wavelengths, Representative The pollutants in The absorption intensity at the wavelength, Represents all pollutants in The average value of the absorption intensity at wavelengths, Represents the number of wavelength points; S113: Based on the spectral feature values ​​of the pollutants, the spectral features of the pollutants are classified, the spectral feature types of the differential pollutants are summarized, and a pollutant spectral feature set is obtained.

[0009] The present invention is improved in that the steps of obtaining the pollutant concentration distribution data are specifically as follows: S211: Based on the pollutant spectral feature set, using known pollutant spectral data, matching the pollutant spectrum in the monitoring data with the known pollutant spectrum, identifying the type of pollutant associated with the groundwater pollution source, and obtaining a pollutant type identification result; S212: Based on the pollutant type identification result, the pollutant concentration at each monitoring point is numerically analyzed using the formula: ; Determine the pollutant concentration at each monitoring point and obtain the pollutant concentration distribution data, where: Indicates The monitoring point is The concentration of pollutants, Representative The monitoring point The spectral absorption intensity of the pollutants, Indicated in The first The volume of the pollutant sample, For the The monitoring point The spectral half-peak width adjustment factor of the pollutant.

[0010] The present invention is improved in that the steps of obtaining the pollution diffusion dynamic index are specifically as follows: S311: calling the pollutant concentration distribution data, combining with the geological background data of the groundwater pollution source, analyzing the flow velocity, flow direction and hydraulic gradient of the groundwater, and obtaining the groundwater flow characteristic parameters; S312: According to the groundwater flow characteristic parameters, the formula is used: ; Calculate groundwater flow rate for each area , and the pollutant migration rate is obtained, where represents the permeability coefficient, represents the hydraulic gradient, represents the saturation thickness, Represents the water flow distance; S313: Based on the pollutant migration rate, combined with pollutant diffusion and changing hydraulic data, the diffusion radius of the pollutant is calculated to obtain a dynamic index of pollution diffusion.

[0011] The present invention is improved in that the steps of obtaining the pollution source assessment index are specifically as follows: S411: Based on the pollution diffusion dynamic index, pollutant flow direction data of different regions are collected, and the reverse flow paths of pollutants in multiple regions are analyzed by combining groundwater flow velocity, hydraulic gradient and pollutant diffusion rate to generate pollution flow reverse trajectory data; S412: Using the pollution flow reverse trajectory data, evaluate the pollutant concentration of the pollution source and its surrounding areas, determine the location of the potential pollution source, and use the formula: ; Calculate the pollution source concentration mutation index ,in, Indicates area The pollutant concentration, Indicates area The affected area, represents the change in pollutant concentration between adjacent areas. represents the distance between regions, is the total number of regions; S413: Analyze the environmental characteristics of the pollution source point and its surrounding area according to the pollution source concentration mutation index, screen the pollution source points with prominent pollution concentration, and obtain the pollution source assessment index.

[0012] The present invention is improved in that the steps further include: S5: Based on the pollution source assessment index, combined with groundwater use conditions and ecological sensitivity, assess the impact of pollution on groundwater quality and potential environmental risks, compare with environmental safety standards, classify the groundwater pollution level in each area, and obtain the groundwater pollution grade; The groundwater pollution level includes severity assessment, emergency response level, and long-term monitoring requirements.

[0013] The present invention is improved in that the steps for obtaining the groundwater pollution level are specifically as follows: S511: Analyze the groundwater environmental vulnerability of each region based on the pollution source assessment index, combined with groundwater use status and ecological sensitivity data, assess the impact of pollution on groundwater quality and potential environmental risks, and obtain a groundwater pollution impact index; S512: Based on the groundwater pollution impact index, the formula is: ; Calculating the groundwater contamination risk index ,in, Indicates area The groundwater pollution impact index, Indicates area water resource utilization rate, is the total number of regions; S513: Based on the groundwater pollution risk index, the groundwater pollution level of each area is classified and compared with the environmental safety standard to obtain the groundwater pollution grade.

[0014] A groundwater pollution source analysis and risk assessment system, the system comprising: The pollutant data acquisition module collects water samples based on the monitoring points arranged in the potential groundwater affected areas, analyzes the organic pollutants, heavy metal content and microbial metabolites in the water samples, collects the characteristic spectral data of pollutants, and obtains the pollutant spectral feature set; The pollutant concentration analysis module uses the known pollutant spectral data to compare with the monitoring data based on the pollutant spectral feature set, identifies the types of pollutants associated with the groundwater pollution source, and performs numerical analysis on the pollutant concentration at each monitoring point to obtain pollutant concentration distribution data; The pollution diffusion analysis module calls the pollutant concentration distribution data, combines the geological background data of the groundwater pollution source, analyzes the groundwater flow characteristics, including flow velocity, flow direction and hydraulic gradient, analyzes the hydraulic parameters that affect the pollution diffusion, and obtains the dynamic index of pollution diffusion; The pollution source tracking module analyzes the reverse trajectory of pollutants in different areas based on the pollution diffusion dynamic indicators, evaluates the location of potential pollution sources, screens pollution source points with prominent pollution concentrations, and obtains a pollution source assessment index; The groundwater pollution assessment module assesses the impact of pollution on groundwater quality and potential environmental risks based on the pollution source assessment index, combined with groundwater usage conditions and ecological sensitivity, and classifies the groundwater pollution level in each area to obtain the groundwater pollution grade.

[0015] Compared with the prior art, the advantages and positive effects of the present invention are: In the present invention, by using LC-MS technology to analyze organic pollutants, heavy metals and microbial metabolites in water samples, accurate detection of trace pollutants is achieved. The normalization of pollutant spectral feature sets improves the level of data standardization, which is convenient for cross-regional data comparison and analysis. Automated data comparison can quickly identify pollution sources, reduce errors, and improve response speed. The detailed analysis of spatial distribution data provides a comprehensive picture of pollution diffusion, making risk assessment more comprehensive. The analysis of pollutant migration rate and diffusion radius combined with geological background and hydrodynamic data enhances the accuracy of groundwater analysis and provides a basis for the formulation of groundwater protection and remediation strategies. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 A flow chart of the groundwater pollution source analysis and risk assessment method proposed for the present invention; Figure 2 It is a flow chart of obtaining the pollutant spectral feature set in the present invention; Figure 3 It is a flow chart for obtaining pollutant concentration distribution data in the present invention; Figure 4 This is a flow chart for obtaining the dynamic index of pollution diffusion in the present invention; Figure 5 This is a flow chart for obtaining the pollution source assessment index in the present invention; Figure 6 This is a flow chart for obtaining the groundwater pollution level in the present invention. DETAILED DESCRIPTION

[0017] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0018] In the description of the present invention, it should be understood that the terms "length", "width", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating positions or positional relationships, are based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, in the description of the present invention, the meaning of "multiple" is two or more, unless otherwise clearly and specifically defined. Example

[0019] See also Figure 1 The present invention provides a technical solution: a method for groundwater pollution source analysis and risk assessment, comprising the following steps: S1: Set up monitoring points in potential groundwater-affected areas, collect water samples, analyze organic pollutants, heavy metal content and microbial metabolites in water samples by liquid chromatography-mass spectrometry, collect characteristic spectral data of pollutants, perform normalization processing, and obtain pollutant spectral feature sets; S2: Based on the pollutant spectral feature set, the known pollutant spectral data is compared with the monitoring data to identify the types of pollutants associated with the groundwater pollution source, and the pollutant concentration at each monitoring point is numerically analyzed to determine the pollutant concentration at each monitoring point and obtain the pollutant concentration distribution data; S3: Call pollutant concentration distribution data, combine with geological background data of groundwater pollution sources, analyze groundwater flow characteristics, including flow velocity, flow direction and hydraulic gradient, analyze hydraulic parameters that affect pollution diffusion, calculate the migration rate and diffusion radius of pollutants, and obtain dynamic indicators of pollution diffusion; S4: Based on the dynamic index of pollution diffusion, the reverse trajectory of pollutant flow in different areas is analyzed to evaluate the location of potential pollution sources, and the pollutant concentration data of pollution sources and surrounding areas are compared to screen pollution source points with prominent pollution concentrations to obtain the pollution source assessment index; S5: Based on the pollution source assessment index, combined with groundwater use conditions and ecological sensitivity (referring to ecological functions, ecological restoration capacity, water resource utilization rate, water body connectivity and basin characteristics), assess the impact of pollution on groundwater quality and potential environmental risks, compare with environmental safety standards, classify the groundwater pollution level in each area, and obtain the groundwater pollution grade.

[0020] The pollutant spectral feature set includes spectral peak, characteristic wavelength, and metabolite identifier. The pollutant concentration distribution data includes pollution intensity, pollution range, and key monitoring points. The dynamic indicators of pollution diffusion include migration path, impact area, and dynamic change rate. The pollution source assessment index includes source activity, impact intensity, and risk potential. The groundwater pollution level includes severity evaluation, emergency response level, and long-term monitoring needs.

[0021] See also Figure 2 , the specific steps for obtaining the pollutant spectral feature set are: S111: Set up monitoring points in potential groundwater-affected areas, collect water samples, detect organic pollutants, heavy metal content and microbial metabolites in water samples by liquid chromatography-mass spectrometry, extract spectral data of each type of pollutant, normalize the spectral data, and obtain normalized spectral data; Monitoring points should be arranged in potential groundwater affected areas. Groundwater areas affected by pollution should be selected to determine the specific locations of monitoring points. Monitoring points should be reasonably arranged according to groundwater flow direction, stratum structure, source of pollutants and diffusion path. For example, monitoring points should be set up at the intersection of industrial emission areas, agricultural fertilization areas and residential areas to ensure that potential pollution diffusion areas are covered. Water samples should be collected using standard sampling techniques. Groundwater samples at different time periods and depths should be collected through on-site sampling equipment such as deep water samplers, peristaltic pumps or sampling bottles. Multiple sampling should be carried out at each monitoring point to ensure the representativeness and repeatability of the data. Organic pollutants and heavy metals in water samples should be detected using liquid chromatography-mass spectrometry technology. Metal content and microbial metabolites, the specific detection steps include sample pretreatment, chromatographic separation, ionization and mass spectrometry analysis, extracting spectral data of each type of pollutant, obtaining characteristic peak information of each pollutant, including spectral absorption peak, emission peak and corresponding wavelength range, normalizing the spectral data, and using data normalization method to normalize the spectral intensity of different pollutants to the same scale to eliminate the influence of factors such as instrument sensitivity and sample concentration differences during the detection process. For example, for a certain type of organic pollutant, the original intensity of its absorption peak is between 5000 and 12000, which is converted into a relative value range of 0 to 1 after normalization to ensure the comparability of spectral data between different pollutants.

[0022] S112: Based on the normalized spectral data, analyze the spectral characteristics of the pollutants, calculate the peak position, absorption intensity and half-peak width, using the formula: ; Get the spectral characteristic values ​​of the pollutants, where: Representative The spectral characteristic values ​​of the pollutants are Representative The pollutants in The peak position at wavelength, Represents all pollutants in The average value of the peak position at wavelengths, Representative The pollutants in The absorption intensity at the wavelength, Represents all pollutants in The average value of the absorption intensity at wavelengths, Represents the number of wavelength points; Analyze the spectral characteristics of pollutants, extract features from the spectral data of different pollutants, and calculate the peak position, absorption intensity and half-peak width. The peak position is determined by calculating the maximum point of the spectral curve. For example, the absorption peak of a pollutant appears at 260nm, 340nm and 450nm. The absorption intensity is obtained by calculating the integral area or maximum absorbance value under the spectral curve. For example, the absorption intensity of a pollutant at 260nm is 0.85, at 340nm is 0.63, and at 450nm is 0.74. The half-peak width is defined as the width of the wavelength interval corresponding to half the height of the peak. If the peak positions of a pollutant at wavelengths of 260nm, 340nm and 450nm are respectively: , the absorption intensities are: , calculate the mean of the pollutant spectrum peak position: ; Calculate the mean of the pollutant spectral absorption intensity: ; Calculate the square deviation at each wavelength point: ; ; ; Calculate the squared deviation of the absorption intensity: ; ; ; Calculate the spectral characteristic values ​​of pollutants: ; ; ; The pollutant spectral characteristic value 6066.69 was obtained. This result shows that the spectral characteristic of the pollutant has a specific offset and can be used for subsequent classification and pollutant identification.

[0023] S113: based on the spectral characteristic values ​​of the pollutants, classifying the spectral characteristic types of the pollutants, and obtaining a pollutant spectral characteristic set; The spectral characteristics of different pollutants are classified, and the pollutants are divided into different categories according to their spectral characteristic values. For example, pollutants with similar peak positions but large differences in absorption intensity belong to similar chemical categories, while pollutants with large peak position shifts have different chemical structures. The spectral characteristic types of different pollutants are summarized, and a spectral characteristic library is established. For example, for a group of organic pollutants, their spectral characteristic values ​​are 0.0294, 0.0352, and 0.0411, respectively. They can be divided into the same category through cluster analysis or classification algorithm, while for another group of inorganic pollutants, their spectral characteristic values ​​are 0.0783 and 0.0924, etc., which can be classified into another category to obtain the pollutant spectral characteristic set.

[0024] See also Figure 3 , the specific steps for obtaining pollutant concentration distribution data are: S211: Based on the pollutant spectral feature set and using the known pollutant spectral data, the pollutant spectrum in the monitoring data is matched with the known pollutant spectrum to identify the type of pollutant associated with the groundwater pollution source and obtain the pollutant type identification result; Acquire the spectral data of known pollutants, match the pollutant spectrum in the monitoring data with the known pollutant spectrum, extract the characteristic parameters of the pollutant spectrum, including peak wavelength, absorption intensity and spectral morphology parameters, compare the pollutant spectrum information collected in the monitoring data with the known pollutant data, calculate the similarity of the spectral curve at multiple wavelength points, and make a judgment based on the set matching threshold. For example, set the spectral matching threshold to 90%. When the matching degree of the spectral curve of the monitoring data and a known pollutant exceeds 90%, it is judged that the pollutant is the same as the known pollutant. Otherwise, enter the further feature comparison process. For pollutants with a matching degree between 70% and 90%, the characteristic vector deviation calculation method is used for adjustment. By calculating the absorption peak position deviation, absorption intensity deviation and half-peak width deviation, the spectral similarity is comprehensively calculated. The calculation formula is as follows: ,in, Represents monitored pollutants and known pollutants The spectral deviation value, Representative The weight of the spectral feature, Representative monitoring pollutants in The spectral characteristic value at Represents known pollutants in The spectral characteristic value at Represents the number of selected spectral feature points. When setting the weight parameters, adjust them according to the contribution of different spectral features. For example, the weight of the absorption peak position contrast value is set to 0.5, the weight of the absorption intensity contrast value is set to 0.3, and the half-peak width weight is set to 0.2. After calculating the deviation value, if If it is less than the set matching threshold, such as 0.1, the pollutant is considered to be a known pollutant. Otherwise, a secondary comparison is performed and further calculations are performed through the suboptimal matching pollutants in the spectral data to obtain the pollutant type identification result.

[0025] S212: Based on the results of pollutant type identification, the pollutant concentration at each monitoring point is numerically analyzed using the formula: ; Determine the pollutant concentration at each monitoring point and obtain the pollutant concentration distribution data, where: Indicates The monitoring point is The concentration of pollutants, Representative The monitoring point The spectral absorption intensity of the pollutants, Indicated in The first The volume of the pollutant sample, For the The monitoring point The half-peak width adjustment factor of the spectrum of the pollutant; The pollutant concentration at each monitoring point is numerically analyzed, the spectral absorption intensity of the identified pollutants is called, and the sampling volume of the monitoring point is combined for calculation. No. The absorption intensity of the pollutant is 0.92, the sampling volume is 200 mL, and the corresponding spectrum half-peak width is 1.8 nm. The pollutant concentration is calculated as follows: ; The calculated concentration of the pollutant is 65.71 mg / L, which can be used to evaluate the pollutant concentration at the monitoring point and obtain pollutant concentration distribution data.

[0026] See also Figure 4 , the specific steps for obtaining the dynamic indicators of pollution diffusion are as follows: S311: calling pollutant concentration distribution data, combining with geological background data of groundwater pollution sources, analyzing groundwater flow velocity, flow direction and hydraulic gradient, and obtaining groundwater flow characteristic parameters; Combined with the geological background data of the groundwater pollution source, the flow rate, flow direction and hydraulic gradient of the groundwater are obtained. The flow rate of groundwater can be obtained by monitoring the water flow velocity at different depths and locations. It is usually measured by a flow meter or tracer experiment. For example, in a polluted site, groundwater observation wells are laid out, the groundwater level elevation is measured regularly, and the flow rate is calculated using Darcy's law. The determination of the flow direction depends on the direction of the water head gradient. The groundwater isolevel can be drawn using the water level measurement data to determine the direction of groundwater flow. The calculation of the hydraulic gradient is based on the water head difference at different observation points divided by their horizontal distance. For example, in a certain industrial pollution site, assuming that the water levels of the two observation wells A and B are 32.5m and 30.2m respectively, and the horizontal distance is 100m, then the hydraulic gradient The calculated hydraulic gradient is used to further analyze the groundwater dynamic characteristics. After obtaining the data, it is necessary to perform normalization processing to eliminate measurement errors, and use interpolation methods to complete the missing data to ensure data integrity. Combined with historical monitoring data, the changing trends of groundwater dynamic characteristics in different time periods are analyzed to obtain groundwater flow characteristic parameters.

[0027] S312: Based on the groundwater flow characteristic parameters, the formula is used: ; Calculate groundwater flow rate for each area , and the pollutant migration rate is obtained, where Permeability stands for coefficient of permeability, which is a measure of the ability of soil or rock to allow water to flow through it. stands for hydraulic gradient, which refers to the head loss per unit distance and is used to calculate the dynamic driving force of water flow in the soil. represents the saturated thickness, i.e. the thickness of the area where groundwater is completely saturated. This parameter affects the amount of water flowing through the groundwater. represents the flow distance, i.e., the distance the contaminant migrates in groundwater; At a contaminated site, the following data was collected: Permeability coefficient (measured by pumping test); Hydraulic gradient (calculated through observation well water level measurement); Saturation Thickness (measured by geological profile); Water flow distance (Horizontal distance from the pollution source to the observation well).

[0028] Substitute the values ​​into the formula to calculate: ; ; The calculation results show that the groundwater contamination migration rate in the selected area is , which can be used to predict the diffusion rate of pollutants and further evaluate their environmental impact to obtain the pollutant migration rate.

[0029] S313: Based on the pollutant migration rate, combined with the pollutant diffusion and changing hydraulic data, the diffusion radius of the pollutants is calculated to obtain the dynamic index of pollution diffusion; The diffusion radius of pollutants is calculated by combining the changes in the diffusion coefficient of pollutants and the hydraulic gradient. The calculation of the diffusion radius needs to take into account the longitudinal diffusion and lateral diffusion effects of pollutants in groundwater. The longitudinal diffusion can be determined by the groundwater flow velocity and the diffusion coefficient. For example, the longitudinal diffusion coefficient of a contaminated site is , while the lateral diffusion is related to the groundwater velocity and formation characteristics. For example, the lateral diffusion coefficient is By calculating the diffusion range of pollutants in different directions and calibrating it with observation data, the diffusion range of pollutants in groundwater can be determined. In the calculation process, numerical simulation or analytical methods are used to solve the problem, and combined with the changes in hydraulic gradient, the dynamic index of pollution diffusion is obtained.

[0030] See also Figure 5 , the specific steps for obtaining the pollution source assessment index are as follows: S411: Based on the dynamic indicators of pollution diffusion, collect pollutant flow data in different areas, combine groundwater flow velocity, hydraulic gradient and pollutant diffusion rate, analyze the reverse flow path of pollutants in multiple areas, and generate pollution flow reverse trajectory data; Data can be collected over a long period of time through the deployment of groundwater monitoring wells and hydrological detection equipment. For example, in an industrial area, groundwater level meters and flow rate meters are installed to record the velocity and direction of groundwater at fixed time intervals to form a flow data set. The pollutant flow data is processed in combination with the groundwater velocity, hydraulic gradient and pollutant diffusion rate to extract the pollutant diffusion trend. The groundwater velocity can be calculated using Darcy's law, and the hydraulic gradient is obtained by dividing the groundwater level difference by the horizontal distance. For example, at a certain site, if the water level difference between two observation wells is 1.8m and the spacing is 150m, the hydraulic gradient is 0.012, and the pollutant diffusion rate is determined by the longitudinal diffusion coefficient and the flow velocity. For example, assuming the longitudinal diffusion coefficient of the site is 0.2 , then the diffusion rate can be calculated by fitting the experimental data. Using the parameters, a pollutant diffusion range map is drawn, and combined with the changes in groundwater flow velocity and hydraulic gradient, the flow characteristics of pollutants in a specific area are analyzed. Subsequently, the flow direction of pollutants is deduced through the reverse trajectory, and the area of ​​the pollution source is inferred. For example, the pollutant concentrations measured at the three observation points A, B, and C are 0.6 mg / L, 0.4 mg / L, and 0.2 mg / L, respectively. The diffusion direction of the pollutant is calculated by the concentration gradient, and the location of the pollution source is traced. Finally, the reverse trajectory data of the pollution flow direction is generated through reverse trajectory deduction.

[0031] S412: Use the reverse trajectory data of pollution flow to evaluate the concentration of pollutants in the pollution source and its surrounding areas and determine the location of potential pollution sources using the formula: ; Calculate the pollution source concentration mutation index ,in, Indicates area The concentration of pollutants is used to quantify the level of pollution in a specific area. Indicates area The area of ​​influence is used to consider the spatial distribution range of pollutant concentrations. Indicates the change in pollutant concentration between adjacent areas and is used to identify the rate of change of pollution levels between different areas. Indicates the distance between regions, which is closely related to the spatial distribution of pollutants and is used to assess the spatial impact of pollutant transmission. is the total number of regions; First, the pollutant concentrations at each pollution source point were measured. For example, in a polluted site, three different areas were selected and the pollutant concentrations were measured. , , The affected areas of each region are , , , calculate the ratio of pollutant concentration to affected area, and compare the changes in pollutant concentration in each area. If the change in pollutant concentration between adjacent areas is , the distance increment between regions , then substitute the numerical calculation into: ; ; ; The pollution source concentration mutation index It reflects the degree of dramatic change in pollution concentration at pollution source points. The larger the index is, the more obvious the change in pollutant concentration is. This calculated value can be used to screen pollution source points with prominent pollution concentrations and obtain the pollution source concentration mutation index.

[0032] S413: Analyze the environmental characteristics of the pollution source point and its surrounding area according to the pollution source concentration mutation index, screen the pollution source points with prominent pollution concentration, and obtain the pollution source assessment index; Using the pollutant diffusion range data, we extract areas with a larger pollutant concentration mutation index and conduct a detailed investigation of the environmental conditions in the area. For example, in an industrial pollution site, we select the pollution source point with the highest mutation index for soil and groundwater testing, analyze its pollution diffusion characteristics, and compare the historical data of the pollution source point to determine whether its pollution source matches the existing emission records. If there is a pollution concentration beyond the normal range, we further investigate the composition characteristics of the pollutants to identify the type of pollution source. For example, if the heavy metal concentration measured in a certain area is 2.5 mg / L, and the surrounding area is only 0.3 mg / L, it means that the area is the main pollution source point, and then establish a priority ranking of pollution source points. By calculating the impact weights between pollution source points, we screen out pollution source points with prominent pollution concentrations and obtain the pollution source assessment index.

[0033] See also Figure 6 , the specific steps for obtaining the groundwater pollution level are: S511: Based on the pollution source assessment index, combined with groundwater use status and ecological sensitivity data, analyze the groundwater environmental vulnerability of each region, assess the impact of pollution on groundwater quality and potential environmental risks, and obtain the groundwater pollution impact index; Analyze the groundwater environmental vulnerability of each region. In this process, first collect groundwater use data and ecological sensitivity data for each region. For example, in industrial areas, taking into account high pollutant loads and high water resource utilization rates, combine factors with pollution source assessment indexes, and use geographic information systems (GIS) for data integration and analysis to identify areas with high groundwater environmental vulnerability. By calculating the pollution impact potential of each region, further assess the impact of pollution on groundwater quality, and integrate data such as ecological functions, resilience, and water connectivity in the region, analyze the potential environmental risks of pollution to ecologically sensitive areas, and obtain the groundwater pollution impact index.

[0034] S512: Based on the groundwater pollution impact index, the formula is: ; Calculating the groundwater contamination risk index ,in, Indicates area The groundwater pollution impact index is a comprehensive value that reflects the groundwater pollution status and its potential environmental impact in the region. Indicates area The water resource utilization rate is used to measure the intensity of water resource use in a region. A high utilization rate indicates that the region is more sensitive to changes in water quality. is the total number of regions; There are three regions, whose pollution impact index and water resource utilization rate are: Region 1: , ; Region 2: , ; Region 3: , ; Substitute the values ​​to calculate: ; ; Calculation results It shows that the overall groundwater pollution risk index is 0.66, and the value can be used to further compare with environmental safety standards to determine which areas have groundwater pollution risks exceeding the safety threshold and take appropriate environmental management measures accordingly.

[0035] S513: Based on the groundwater pollution risk index, the groundwater pollution level of each area is classified and compared with the environmental safety standard to obtain the groundwater pollution grade; The groundwater pollution level of each region is classified by comparing it with the environmental safety standards. First, the groundwater pollution risk index calculated above is analyzed and compared with the environmental safety standards. For example, if the groundwater pollution risk index exceeds 0.8 (the threshold is based on the safety standards of the local environmental protection bureau), the region is classified as a high pollution level. In this way, the groundwater pollution level of each region will be clarified so that corresponding pollution control and governance measures can be formulated. Based on the analysis results, specific pollution control strategies for each region are formulated to generate the groundwater pollution level.

[0036] A groundwater pollution source analysis and risk assessment system, the system comprising: The pollutant data acquisition module collects water samples based on the monitoring points arranged in the potential groundwater affected areas, analyzes the organic pollutants, heavy metal content and microbial metabolites in the water samples, collects the characteristic spectral data of pollutants, and obtains the pollutant spectral feature set; The pollutant concentration analysis module uses the known pollutant spectral data to compare with the monitoring data based on the pollutant spectral feature set, identifies the types of pollutants associated with groundwater pollution sources, and performs numerical analysis on the pollutant concentration at each monitoring point to obtain pollutant concentration distribution data; The pollution diffusion analysis module calls the pollutant concentration distribution data, combines the geological background data of the groundwater pollution source, analyzes the groundwater flow characteristics, including flow velocity, flow direction and hydraulic gradient, analyzes the hydraulic parameters that affect the pollution diffusion, and obtains the dynamic indicators of pollution diffusion; The pollution source tracking module analyzes the reverse trajectory of pollutants in different areas based on the dynamic indicators of pollution diffusion, evaluates the location of potential pollution sources, screens pollution source points with prominent pollution concentrations, and obtains the pollution source assessment index; The groundwater pollution assessment module evaluates the impact of pollution on groundwater quality and potential environmental risks based on the pollution source assessment index, combined with groundwater usage conditions and ecological sensitivity, and classifies the groundwater pollution level in each area to obtain the groundwater pollution grade.

[0037] The above are only preferred embodiments of the present invention and are not intended to limit the present invention in other forms. Any technician familiar with the profession may use the technical contents disclosed above to change or modify them into equivalent embodiments with equivalent changes and apply them to other fields. However, any simple modification, equivalent change and modification made to the above embodiments based on the technical essence of the present invention without departing from the technical solution of the present invention still falls within the protection scope of the technical solution of the present invention.

Claims

1. A method for groundwater pollution source analysis and risk assessment, characterized in that: The following steps are involved: S1: Set up monitoring points in potential groundwater-affected areas, collect water samples, analyze organic pollutants, heavy metal content and microbial metabolites in water samples, collect characteristic spectral data of pollutants, perform normalization processing, and obtain pollutant spectral feature sets; S2: Based on the pollutant spectral feature set, identify the types of pollutants associated with the groundwater pollution source, and perform numerical analysis on the pollutant concentration at each monitoring point to determine the pollutant concentration at each monitoring point and obtain pollutant concentration distribution data; S3: calling the pollutant concentration distribution data, combining the geological background data of the groundwater pollution source, analyzing the groundwater flow characteristics, analyzing the hydraulic parameters that affect the pollution diffusion, calculating the migration rate and diffusion radius of the pollutants, and obtaining the pollution diffusion dynamic index; S4: Based on the pollution diffusion dynamic indicators, the reverse trajectory of pollutant flow in different areas is analyzed, the location of potential pollution sources is evaluated, and the pollutant concentration data of the pollution sources and their surrounding areas are compared to screen pollution source points with prominent pollution concentrations to obtain the pollution source assessment index.

2. The method for groundwater pollution source analysis and risk assessment according to claim 1, characterized in that: The pollutant spectral feature set includes spectral peak, characteristic wavelength, and metabolite identification; the pollutant concentration distribution data includes pollution intensity, pollution range, and key monitoring points; the pollution diffusion dynamic indicators include migration path, impact area, and dynamic change rate; the pollution source assessment index includes source activity, impact intensity, and risk potential.

3. The method for groundwater pollution source analysis and risk assessment according to claim 1, characterized in that: The steps for obtaining the pollutant spectral feature set are specifically as follows: S111: Set up monitoring points in potential groundwater-affected areas, collect water samples, detect organic pollutants, heavy metal content and microbial metabolites in water samples by liquid chromatography-mass spectrometry, extract spectral data of each type of pollutant, normalize the spectral data, and obtain normalized spectral data; S112: Based on the normalized spectral data, analyze the spectral characteristics of the pollutant, calculate the peak position, absorption intensity and half-peak width, using the formula: ； Get the spectral characteristic values ​​of the pollutants, where: Representative The spectral characteristic values ​​of the pollutants are Representative The pollutants in The peak position at wavelength, Represents all pollutants in The average value of the peak position at wavelengths, Representative The pollutants in The absorption intensity at the wavelength, Represents all pollutants in The average value of the absorption intensity at wavelengths, Represents the number of wavelength points; S113: Based on the spectral feature values ​​of the pollutants, the spectral features of the pollutants are classified, the spectral feature types of the differential pollutants are summarized, and a pollutant spectral feature set is obtained.

4. The method for groundwater pollution source analysis and risk assessment according to claim 1, characterized in that: The steps for obtaining the pollutant concentration distribution data are specifically as follows: S211: Based on the pollutant spectral feature set, using known pollutant spectral data, matching the pollutant spectrum in the monitoring data with the known pollutant spectrum, identifying the type of pollutant associated with the groundwater pollution source, and obtaining a pollutant type identification result; S212: Based on the pollutant type identification result, the pollutant concentration at each monitoring point is numerically analyzed using the formula: ； Determine the pollutant concentration at each monitoring point and obtain the pollutant concentration distribution data, where: Indicates The monitoring point is The concentration of pollutants, Representative The monitoring point The spectral absorption intensity of the pollutants, Indicated in The first The volume of the pollutant sample, For the The monitoring point The spectral half-peak width adjustment factor of the pollutant.

5. The method for groundwater pollution source analysis and risk assessment according to claim 1, characterized in that: The steps for obtaining the pollution diffusion dynamic index are specifically as follows: S311: calling the pollutant concentration distribution data, combining with the geological background data of the groundwater pollution source, analyzing the flow velocity, flow direction and hydraulic gradient of the groundwater, and obtaining the groundwater flow characteristic parameters; S312: According to the groundwater flow characteristic parameters, the formula is used: ； Calculate groundwater flow rate for each area , and the pollutant migration rate is obtained, where represents the permeability coefficient, represents the hydraulic gradient, represents the saturation thickness, Represents the water flow distance; S313: Based on the pollutant migration rate, combined with pollutant diffusion and changing hydraulic data, the diffusion radius of the pollutant is calculated to obtain a dynamic index of pollution diffusion.

6. The method for groundwater pollution source analysis and risk assessment according to claim 1, characterized in that: The steps for obtaining the pollution source assessment index are specifically as follows: S411: Based on the pollution diffusion dynamic index, pollutant flow direction data of different regions are collected, and the reverse flow paths of pollutants in multiple regions are analyzed by combining groundwater flow velocity, hydraulic gradient and pollutant diffusion rate to generate pollution flow reverse trajectory data; S412: Using the pollution flow reverse trajectory data, evaluate the pollutant concentration of the pollution source and its surrounding areas, determine the location of the potential pollution source, and use the formula: ； Calculate the pollution source concentration mutation index ,in, Indicates area The pollutant concentration, Indicates area The affected area, represents the change in pollutant concentration between adjacent areas. represents the distance between regions, is the total number of regions; S413: Analyze the environmental characteristics of the pollution source point and its surrounding area according to the pollution source concentration mutation index, screen the pollution source points with prominent pollution concentration, and obtain the pollution source assessment index.

7. The method for groundwater pollution source analysis and risk assessment according to claim 1, characterized in that: The steps also include: S5: Based on the pollution source assessment index, combined with groundwater use conditions and ecological sensitivity, assess the impact of pollution on groundwater quality and potential environmental risks, compare with environmental safety standards, classify the groundwater pollution level in each area, and obtain the groundwater pollution grade; The groundwater pollution level includes severity assessment, emergency response level, and long-term monitoring requirements.

8. The method for groundwater pollution source analysis and risk assessment according to claim 7, characterized in that: The steps for obtaining the groundwater pollution level are specifically as follows: S511: Analyze the groundwater environmental vulnerability of each region based on the pollution source assessment index, combined with groundwater use status and ecological sensitivity data, assess the impact of pollution on groundwater quality and potential environmental risks, and obtain a groundwater pollution impact index; S512: Based on the groundwater pollution impact index, the formula is: ； Calculating the groundwater contamination risk index ,in, Indicates area The groundwater pollution impact index, Indicates area water resource utilization rate, is the total number of regions; S513: Based on the groundwater pollution risk index, the groundwater pollution level of each area is classified and compared with the environmental safety standard to obtain the groundwater pollution grade.

9. A groundwater pollution source analysis and risk assessment system, characterized in that: According to the method for groundwater pollution source analysis and risk assessment according to any one of claims 1 to 8, the system comprises: The pollutant data acquisition module collects water samples based on the monitoring points arranged in the potential groundwater affected areas, analyzes the organic pollutants, heavy metal content and microbial metabolites in the water samples, collects the characteristic spectral data of pollutants, and obtains the pollutant spectral feature set; The pollutant concentration analysis module uses the known pollutant spectral data to compare with the monitoring data based on the pollutant spectral feature set, identifies the types of pollutants associated with the groundwater pollution source, and performs numerical analysis on the pollutant concentration at each monitoring point to obtain pollutant concentration distribution data; The pollution diffusion analysis module calls the pollutant concentration distribution data, combines the geological background data of the groundwater pollution source, analyzes the groundwater flow characteristics, including flow velocity, flow direction and hydraulic gradient, analyzes the hydraulic parameters that affect the pollution diffusion, and obtains the dynamic index of pollution diffusion; The pollution source tracking module analyzes the reverse trajectory of pollutants in different areas based on the pollution diffusion dynamic indicators, evaluates the location of potential pollution sources, screens pollution source points with prominent pollution concentrations, and obtains a pollution source assessment index; The groundwater pollution assessment module assesses the impact of pollution on groundwater quality and potential environmental risks based on the pollution source assessment index, combined with groundwater usage conditions and ecological sensitivity, and classifies the groundwater pollution level in each area to obtain the groundwater pollution grade.

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