Method and system for tracing and identifying the source of groundwater pollution in mixed areas based on multiple means

Abstract

The present invention relates to the field of pollution detection technology, specifically to a method and system for tracing and identifying groundwater pollution in mixed areas based on multiple means, including the following steps: based on the groundwater pollution area, detecting the raw material storage, transportation and use process of factories in multiple pollution mixed areas, assessing the risk of raw material leakage, assessing the pollution risk of differentiated factories, and obtaining a list of potential pollution sources. The present invention can identify the potential sources of pollutants by investigating and assessing the factory operation status, raw material processing process, production process level, environmental protection measures and other information in the mixed pollution area, and enhance the accuracy of pollution tracing by comparing pollution feature fingerprints. Through isotope tracing analysis, combined with a probabilistic isotope mixing model, the contribution rate of each pollution source to groundwater is calculated, and the pollution diffusion range is assessed in combination with the groundwater flow direction and pollution source location in the mixed pollution area, and the severity of the pollution is analyzed, providing comprehensive data support for pollution source control.

Description

Technical Field

[0001] The present invention relates to the technical field of pollution detection, and in particular to a method and system for tracing and identifying the source of groundwater pollution in a mixed zone based on multiple means. Background Art

[0002] Traditional source identification methods have limitations in dealing with mixed pollution areas, complex samples and real-time data, and it is difficult to quickly and accurately locate specific pollution sources. Especially in industrial and urban environments, the complex pollution background and diverse types of pollutants make it difficult for a single technology or method to fully capture all relevant information, resulting in inaccurate environmental monitoring and pollution assessment. For example, failure to effectively analyze the source and contribution rate of groundwater pollutants will lead to inaccurate governance measures, affect the cost-effectiveness and implementation effect of pollution control, and reduce the implementation of environmental policies and governance effectiveness. Summary of the invention

[0003] The purpose of the present invention is to solve the shortcomings existing in the prior art and to propose a method and system for tracing and identifying the source of groundwater pollution in mixed areas based on multiple means.

[0004] In order to achieve the above-mentioned purpose, the present invention adopts the following technical scheme: a method for tracing and identifying the source of groundwater pollution in a mixed zone based on multiple means, comprising the following steps:

[0005] S1: Based on the groundwater pollution area, detect the raw material storage, transportation and use processes of factories in multiple pollution mixed areas, evaluate the risk of raw material leakage, and evaluate the pollution risk of differentiated factories according to the operation status of factory wastewater treatment and solid waste management facilities to obtain a list of potential pollution sources;

[0006] S2: Based on the potential pollution source list, the pollution characteristic fingerprint of the sample is established according to the characteristic molecular compounds in the groundwater samples of the detection point in the mixed area and the samples of the surrounding potential pollution sources. By comparing the pollution characteristic fingerprints of the detection point and the potential pollution source, the similarity of the pollution characteristic fingerprint is evaluated, the pollution source is identified, and the key pollution source identification information is obtained;

[0007] S3: Based on the identification information of the key pollution sources, the contribution rate of the differentiated pollution sources to groundwater pollution is calculated by analyzing the isotopic composition of groundwater and pollution sources and combining the probabilistic isotope mixing model to obtain the groundwater pollution contribution assessment result;

[0008] S4: Based on the groundwater pollution contribution assessment results, combined with the groundwater runoff direction in the mixed pollution area and the location of the pollution source, the impact range of the differentiated pollution sources is assessed, and the severity of the pollution is assessed according to the type, concentration and physical and chemical properties of the pollutants to obtain the pollution source tracing assessment results.

[0009] The present invention is improved in that the method for assessing the risk of raw material leakage is:

[0010] S111: Based on the groundwater pollution area, collect data on the storage, transportation and use of raw materials in factories in the mixed pollution area to obtain raw material leakage related data;

[0011] S112: Based on the raw material leakage related data, the formula:

[0012] ;

[0013] Calculate the raw material leakage risk index ,in, Represents the danger of raw materials, Indicates the storage security measure score, Indicates the score of transportation safety measures, Indicates the degree of environmental impact, is the adjustment parameter, and is the weight coefficient, is the environmental impact adjustment factor, is the raw material leakage risk index;

[0014] S113: Based on the raw material leakage risk index ,according to The leakage risk is evaluated based on the value and the leakage risk assessment result is obtained.

[0015] The present invention is improved in that the steps of obtaining the potential pollution source list are:

[0016] S121: Based on the raw material leakage risk index , collect operational data of the factory’s wastewater treatment and solid waste management facilities, including wastewater treatment volume, wastewater treatment efficiency, and solid waste discharge;

[0017] S122: Based on the operation data, by formula:

[0018] ;

[0019] Calculate the pollution risk index for each factory ,in, is the raw material leakage risk index, is the wastewater treatment volume, For wastewater treatment efficiency, For solid waste management emission levels, and is the adjustment factor, is the pollution risk index;

[0020] S123: Based on the pollution risk index , compared with the preset pollution risk threshold, Factories whose values ​​exceed the preset pollution risk threshold are marked as potential pollution sources, and a list of potential pollution sources is obtained.

[0021] The present invention is improved in that the method for establishing the contamination characteristic fingerprint of the sample is:

[0022] S211: Based on the list of potential pollution sources, samples are collected from groundwater detection points and potential pollution sources, and characteristic molecular compounds in the samples are analyzed by ultra-high performance liquid chromatography-high resolution time-of-flight mass spectrometry and gas chromatography-mass spectrometry, wherein the characteristic molecular compounds include drugs, pesticides, veterinary drugs, personal care products, industrial chemicals, plasticizers and flame retardants, and the concentrations of the characteristic molecular compounds are detected to obtain characteristic molecular compound data;

[0023] S212: Based on the characteristic molecular compound data, by formula:

[0024] ;

[0025] Calculate the contamination signature fingerprint of the sample ,in, is the total number of compounds detected, It is The weight coefficient of the compound, For the The concentration of the compound, For the The coefficient of variation of the compound, It is the pollution characteristic fingerprint.

[0026] The present invention is improved in that the step of obtaining the key pollution source identification information is:

[0027] S221: Based on the pollution characteristic fingerprint , the sample feature fingerprint of the detection point Sample characteristic fingerprints with potential contamination sources For comparison, use the formula:

[0028] ;

[0029] Calculating Similarity ,in, For the The weight coefficient of the test, For the The characteristic fingerprint of the sample at the detection point in the detection, For the The characteristic fingerprint of the potential contamination source samples in the first test, is the number of detections, for similarity;

[0030] S222: Based on the similarity , compared with the preset similarity threshold, the pollution sources exceeding the similarity threshold are marked as key pollution sources, and the key pollution source identification information is obtained.

[0031] The present invention is improved in that the steps of obtaining the groundwater pollution contribution assessment result are:

[0032] S311: Based on the key pollution source identification information, collect isotope tracer samples from groundwater monitoring points and designated pollution sources, conduct isotope tracer analysis, and obtain isotope data of groundwater samples and pollution source samples;

[0033] S312: Based on the isotope data of the groundwater sample and the pollution source sample, the formula:

[0034] ;

[0035] Calculate the logarithmic difference of isotope ratios ,in, is the isotope ratio in the groundwater sample, is the isotope ratio in the pollution source sample, is the logarithmic difference of isotope ratios;

[0036] S313: Based on the logarithmic difference of the isotope ratio , through the formula:

[0037] ;

[0038] Calculate pollution contribution , and according to The value is combined with the probabilistic isotope mixing model to evaluate the contribution of differentiated pollution sources to groundwater pollution and obtain the groundwater pollution contribution assessment results, among which, is the logarithmic difference of the isotope ratios, The pollution contribution rate is is the largest isotopic difference, is the stability constant, is the index parameter.

[0039] The present invention is improved in that the method for evaluating the impact range of differentiated pollution sources is:

[0040] S411: Collect groundwater flow data, including flow direction and velocity, and identify the distance between the pollution source and the dominant groundwater channel by marking the location of the pollution source on the map to obtain range association data;

[0041] S412: Based on the range association data, by formula:

[0042] ;

[0043] Calculate the impact of pollutants ,in, is the impact range of the pollutant, is the diffusion coefficient, is the groundwater flow velocity, It's time. is the straight-line distance from the pollution source to the dominant groundwater channel, is the groundwater penetration depth coefficient, is the base of natural logarithms.

[0044] The present invention is improved in that the steps of obtaining the pollution source tracing assessment result are:

[0045] S421: Classify pollutants released by differentiated pollution sources, record the chemical types and physical and chemical properties of pollutants, and obtain pollutant-related data;

[0046] S422: Based on the pollutant association data and the impact range of the pollutant , through the formula:

[0047] ;

[0048] Calculating pollution severity ,in, It is a pollutant The concentration of It is a pollutant The scope of influence, It is a pollutant The toxicity threshold is the distance decay factor, is the base of natural logarithms, The severity of pollution, is the number of pollutant types;

[0049] S423: Based on the severity of the pollution , integrate the groundwater pollution contribution assessment results to obtain the pollution source assessment results.

[0050] A mixed zone groundwater pollution source tracing identification system based on multiple means, the mixed zone groundwater pollution source tracing identification system based on multiple means is used to execute the mixed zone groundwater pollution source tracing identification method based on multiple means, the system comprises:

[0051] The potential pollution source identification module evaluates the risk of raw material leakage in factories around the contaminated area based on the groundwater contamination area, and evaluates the pollution risk according to the operating conditions of the factory's wastewater treatment and solid waste management facilities to obtain a list of potential pollution sources;

[0052] The key pollution source identification module establishes the pollution characteristic fingerprint of the sample based on the potential pollution source list and the characteristic molecular compounds in the groundwater sample at the detection point and the potential pollution source sample, identifies the pollution source by comparing the similarity between the pollution characteristic fingerprints of the detection point and the potential pollution source, and obtains the key pollution source identification information;

[0053] The pollution contribution analysis module analyzes the isotopic composition of groundwater and pollution sources based on the key pollution source identification information, and calculates the contribution rate of differentiated pollution sources to groundwater pollution by combining the probabilistic isotope mixing model to obtain the groundwater pollution contribution assessment result;

[0054] The pollution impact assessment module evaluates the impact range of the differentiated pollution sources based on the groundwater pollution contribution assessment result and the groundwater runoff direction and the location of the pollution source to obtain an impact range assessment result;

[0055] The pollution risk assessment module evaluates the severity of the pollution based on the impact scope assessment results and according to the pollutant type, concentration and physical and chemical properties to obtain the pollution source tracing assessment results.

[0056] Compared with the prior art, the advantages and positive effects of the present invention are:

[0057] In the present invention, by investigating and evaluating the factory operation status, raw material processing process, production process level, environmental protection measures and other information in the mixed pollution area, the potential source of pollutants can be identified, and the accuracy of pollution tracing is enhanced by comparing the pollution characteristic fingerprints, making the identification of pollution sources more direct and effective. Through isotope tracing analysis combined with the probabilistic isotope mixing model, the contribution rate of each pollution source to groundwater is calculated, which provides a scientific basis for formulating control strategies and makes pollution control measures more targeted and efficient. Combined with the groundwater flow direction and pollution source location in the mixed pollution area, the pollution spread range is evaluated, and the severity of the pollution is analyzed, providing comprehensive data support for pollution source control. BRIEF DESCRIPTION OF THE DRAWINGS

[0058] Figure 1 is a flow chart of the method of the present invention;

[0059] Figure 2 A flow chart for assessing the risk of raw material leakage for the present invention;

[0060] Figure 3 A flow chart for obtaining a list of potential pollution sources for the present invention;

[0061] Figure 4 A flow chart for establishing a contamination characteristic fingerprint of a sample for the present invention;

[0062] Figure 5 A flow chart for obtaining key pollution source identification information for the present invention;

[0063] Figure 6 A flow chart for obtaining groundwater contamination contribution assessment results for the present invention;

[0064] Figure 7 A flow chart for evaluating the impact range of differentiated pollution sources for the present invention;

[0065] Figure 8 The present invention is a flow chart for obtaining pollution source tracing assessment results. DETAILED DESCRIPTION

[0066] 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.

[0067] 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.

[0068] See also Figure 1 The present invention provides a technical solution: a method for tracing and identifying the source of groundwater pollution in a mixed zone based on multiple means, comprising the following steps:

[0069] S1: Based on the groundwater pollution area, detect the raw material storage, transportation and use processes of factories in multiple pollution mixed areas, evaluate the risk of raw material leakage, and evaluate the pollution risk of differentiated factories according to the operation status of factory wastewater treatment and solid waste management facilities to obtain a list of potential pollution sources;

[0070] S2: Based on the potential pollution source list, the pollution characteristic fingerprint of the sample is established according to the characteristic molecular compounds in the groundwater samples of the detection point in the mixed area and the samples of the surrounding potential pollution sources. By comparing the pollution characteristic fingerprints of the detection point and the potential pollution source, the similarity of the pollution characteristic fingerprint is evaluated, the pollution source is identified, and the key pollution source identification information is obtained;

[0071] S3: Based on the identification information of the key pollution sources, the contribution rate of the differentiated pollution sources to groundwater pollution is calculated by analyzing the isotopic composition of groundwater and pollution sources and combining the probabilistic isotope mixing model to obtain the groundwater pollution contribution assessment result;

[0072] S4: Based on the groundwater pollution contribution assessment results, combined with the groundwater runoff direction in the mixed pollution area and the location of the pollution source, the impact range of the differentiated pollution sources is assessed, and the severity of the pollution is assessed according to the type, concentration and physical and chemical properties of the pollutants to obtain the pollution source tracing assessment results.

[0073] The list of potential pollution sources includes factory name, factory location, type of pollutants and potential leakage points. The key pollution source identification information includes pollution source location information, pollutant compound identification and similarity score. The groundwater pollution contribution assessment results include the contribution percentage of the pollution source, the affected groundwater area and key pollutants. The pollution source tracing assessment results include the pollution source number, impact range information and severity level.

[0074] See also Figure 2 , the method for assessing the risk of raw material leakage is:

[0075] S111: Based on the groundwater pollution area, collect data on the storage, transportation and use of raw materials in factories in the mixed pollution area to obtain raw material leakage related data;

[0076] S112: Based on the raw material leakage correlation data, through the formula:

[0077] ;

[0078] Calculate the raw material leakage risk index ,in, Represents the danger of the raw materials, Indicates the storage security measure score, Indicates the score of transportation safety measures, Indicates the degree of environmental impact, is the adjustment parameter, and is the weight coefficient, is the environmental impact adjustment factor, is the raw material leakage risk index;

[0079] S113: Based on the raw material leakage risk index ,according to The leakage risk is evaluated based on the value and the leakage risk assessment result is obtained.

[0080] formula:

[0081] ;

[0082] Parameter details and how to obtain them:

[0083] Indicates the hazard of raw materials, usually assessed by comparing them with the Material Safety Data Sheet, which provides specific hazard information and safety levels for each chemical substance. The specific hazard index can be quantified based on the hazard categories in the Material Safety Data Sheet, such as flammability, toxicity, and corrosivity.

[0084] It is the storage safety measure score, obtained from the factory's safety management report. The score reflects the safety of the storage area, such as fire prevention, leakage prevention and chemical isolation level. The safety score can be quantified by experts through the compliance inspection results in the safety audit.

[0085] Indicates the transport safety measure score, which is also determined based on the safety management report. The transport score takes into account the safety configuration of the transport vehicle, monitoring during transportation, and emergency response mechanisms. This score can be quantified by experts by evaluating the accident record and preventive measures during transportation.

[0086] The environmental impact is usually provided by an environmental impact assessment study, which includes the potential impacts that the release of raw materials may have on the surrounding ecosystem and human health.

[0087] , , and It is to adjust the parameters to adjust the sensitivity of the model according to the specific situation. The parameters should be set based on past case studies and expert opinions, and adjusted in actual applications to optimize the model prediction.

[0088] Calculation example:

[0089] Assume we have the following parameters:

[0090] , indicating that the raw material is highly dangerous.

[0091] , indicating that the storage safety measures score high.

[0092] , indicating that the transportation measures are relatively safe.

[0093] , indicating that the environmental impact is low.

[0094] , , , , the coefficients are set based on past experience.

[0095] Substitute the parameters into the risk calculation:

[0096] ;

[0097] The calculation process is as follows:

[0098] , increasing the impact intensity of the hazardousness of the raw materials.

[0099] , reflecting adjustments to storage safety measures.

[0100] , reflecting adjustments to transportation safety measures.

[0101] Calculated Risk:

[0102] ;

[0103] result , whose value is high, means that further safety improvement measures are needed under the current safety measures and environmental impact considerations.

[0104] See also Figure 3 , the steps to obtain the list of potential pollution sources are:

[0105] S121: Based on the raw material leakage risk index , collect operational data of the factory’s wastewater treatment and solid waste management facilities, including wastewater treatment volume, wastewater treatment efficiency, and solid waste discharge;

[0106] S122: Based on the operating data, by formula:

[0107] ;

[0108] Calculate the pollution risk index for each factory ,in, is the raw material leakage risk index, is the wastewater treatment volume, For wastewater treatment efficiency, For solid waste management emission levels, and is the adjustment factor, is the pollution risk index;

[0109] S123: Based on pollution risk index , compared with the preset pollution risk threshold, Factories whose values ​​exceed the preset pollution risk threshold are marked as potential pollution sources, and a list of potential pollution sources is obtained.

[0110] formula:

[0111] ;

[0112] Parameter details and how to obtain them:

[0113] Raw material leakage risk: represents the risk of raw material leakage in the factory, which is calculated through the previous steps.

[0114] Wastewater treatment volume: It is the amount of wastewater treated by the factory every day. It is usually provided by the factory operation data. The parameters reflect the factory's ability to treat wastewater.

[0115] Wastewater treatment efficiency: Parameter derived by evaluating the performance of wastewater treatment facilities, usually by comparing chemical analyses of the wastewater before and after treatment.

[0116] Solid waste management emission level: It indicates the amount of solid waste discharged by the factory, which can be obtained through emission records of environmental protection departments or factory self-reporting.

[0117] Small adjustment factor: Used to ensure that the denominator of wastewater efficiency is not zero, usually set to a small constant.

[0118] Solid waste emission adjustment factor: It is a weighting factor used to adjust the impact of solid waste emissions on the overall risk assessment, usually set based on past environmental impact studies and expert advice.

[0119] Calculation example:

[0120] Assume the following parameters:

[0121] , indicating a higher risk of raw material leakage.

[0122] m³ / day, wastewater treatment capacity.

[0123] , efficient wastewater treatment.

[0124] Tons / year, a certain amount of solid waste emissions.

[0125] , a small constant to prevent division by zero errors.

[0126] , adjustment coefficient for solid waste emissions,

[0127] calculate :

[0128] ;

[0129] Calculation steps:

[0130] Adjustment of wastewater treatment efficiency:

[0131] ;

[0132] Adjustment of solid waste discharge:

[0133] ;

[0134] Risk Score:

[0135] ;

[0136] Calculation results , indicating that after taking into account adjustment factors for wastewater treatment and solid waste emissions, the plant's overall pollution risk score is 131.0, which is a high risk value, meaning that the plant may be an important environmental monitoring target.

[0137] See also Figure 4 , the method to establish the contamination characteristic fingerprint of the sample is:

[0138] S211: Based on the list of potential pollution sources, samples are collected from groundwater detection points and potential pollution sources, and characteristic molecular compounds in the samples are analyzed by ultra-high performance liquid chromatography-high resolution time-of-flight mass spectrometry and gas chromatography-mass spectrometry, wherein the characteristic molecular compounds include drugs, pesticides, veterinary drugs, personal care products, industrial chemicals, plasticizers and flame retardants, and the concentrations of the characteristic molecular compounds are detected to obtain characteristic molecular compound data;

[0139] S212: Based on the characteristic molecular compound data, the formula:

[0140] ;

[0141] Calculate the contamination signature fingerprint of the sample ,in, is the total number of compounds detected, It is The weight coefficient of the compound, For the The concentration of the compound, For the The coefficient of variation of the compound, It is the pollution characteristic fingerprint.

[0142] formula:

[0143] ;

[0144] Parameter details and how to obtain them:

[0145] Total number of compounds detected: represents the types of characteristic molecular compounds analyzed in all samples. The total number of compounds is determined by chemical analysis methods such as high performance liquid chromatography mass spectrometry (HPLC-MS) and gas chromatography mass spectrometry (GC-MS) to detect the types of compounds in the samples.

[0146] Weight: The weight is set according to the environmental impact and detection frequency of the compound, reflecting the potential harm of different compounds in the environment and the importance of monitoring. The weight of each compound is determined through a comprehensive evaluation of historical pollution incidents and environmental impact studies.

[0147] Compound concentration: The concentration of a compound is measured in a sample by high performance liquid chromatography-mass spectrometry (HPLC-MS) and gas chromatography-mass spectrometry (GC-MS). The compound concentration is expressed as its actual measured value in the sample.

[0148] Coefficient of variation: reflects the degree of variation of compound concentration in different samples. The standard deviation and mean value are calculated through statistical analysis of the compound concentration in multiple samples.

[0149] Calculation example:

[0150] Assume the following parameters:

[0151] : Four compounds were analyzed.

[0152] : An array of weights, determined through historical pollution events and environmental impact studies.

[0153] : The concentration of each compound.

[0154] : Coefficient of variation of the compound, calculated by statistical analysis.

[0155] Calculation steps:

[0156] Calculate the adjusted concentration value for each compound:

[0157] ;

[0158] ;

[0159] ;

[0160] ;

[0161] Add up all adjusted concentration values:

[0162] ;

[0163] The natural logarithm is used in the calculation process, and the calculation result Represents the contamination characteristic fingerprint of the sample.

[0164] See also Figure 5 , the steps to obtain key pollution source identification information are:

[0165] S221: Based on pollution feature fingerprint , the sample feature fingerprint of the detection point Sample characteristic fingerprints with potential contamination sources For comparison, use the formula:

[0166] ;

[0167] Calculating Similarity ,in, For the The weight coefficient of the test, For the The characteristic fingerprint of the sample at the detection point in the detection, For the The characteristic fingerprint of the potential contamination source samples in the first test, is the number of detections, for similarity;

[0168] S222: Based on similarity , compared with the preset similarity threshold, the pollution sources exceeding the similarity threshold are marked as key pollution sources, and the key pollution source identification information is obtained.

[0169] formula:

[0170] ;

[0171] Parameter details and how to obtain them:

[0172] : The number of tests involved in the calculation, representing the total number of tests performed in a given study, Obtained directly from the project's monitoring plan, based on predetermined sample collection frequencies and periodicity settings.

[0173] : No. The weight coefficient of a test reflects the weight of the test and can be set by an expert.

[0174] and :They are The characteristic fingerprints of the detection point samples and potential pollution source samples in the detection are calculated by the previous steps.

[0175] Calculation example:

[0176] Assume the following parameters:

[0177] : A total of three tests were conducted.

[0178] : Detection number weight.

[0179] : Characteristic fingerprint of the sample at the detection point.

[0180] : Characteristic fingerprints of potential pollution source samples.

[0181] Calculation process:

[0182] ;

[0183] Molecular computing:

[0184] ;

[0185] Denominator calculation:

[0186] Left item:

[0187] ;

[0188] Right item:

[0189] ;

[0190] Calculate similarity:

[0191] ;

[0192] What you get The value is about 0.98, indicating that the chemical composition of the detection point and the pollution source are very similar, and the high similarity index strongly indicates that the detection point sample originated from the pollution source.

[0193] See also Figure 6 , the steps to obtain the groundwater pollution contribution assessment results are:

[0194] S311: Based on the key pollution source identification information, collect isotope tracer samples from groundwater monitoring points and designated pollution sources, conduct isotope tracer analysis, and obtain isotope data of groundwater samples and pollution source samples;

[0195] S312: Based on the isotope data of groundwater samples and pollution source samples, the formula:

[0196] ;

[0197] Calculate the logarithmic difference of isotope ratios ,in, is the isotope ratio in the groundwater sample, is the isotope ratio in the pollution source sample, is the logarithmic difference of isotope ratios;

[0198] S313: Logarithmic differences based on isotope ratios , through the formula:

[0199] ;

[0200] Calculate pollution contribution rate , and according to The value is combined with the probabilistic isotope mixing model to evaluate the contribution of differentiated pollution sources to groundwater pollution and obtain the groundwater pollution contribution assessment results, among which, is the logarithmic difference of the isotope ratio, The pollution contribution rate is is the largest isotopic difference, is the stability constant, is the index parameter.

[0201] formula:

[0202] ;

[0203] Parameter details and how to obtain them:

[0204] : Isotope ratio in groundwater samples. The groundwater samples are measured by isotope mass spectrometry to obtain the proportion of specific isotopes such as hydrogen or oxygen.

[0205] :Isotope ratio in pollution source samples. The pollution source samples are measured by isotope mass spectrometry analysis technology to obtain the ratio of specific isotopes.

[0206] : The largest isotopic difference among all samples, calculated by comparing all values, find the maximum value among them.

[0207] : A stable constant, a small positive number that prevents division by zero errors. It is set according to the needs of the calculation and usually takes a very small value.

[0208] : An exponential parameter that adjusts the sensitivity of pollution contribution is selected based on the distribution characteristics of the actual data to optimize the sensitivity and response of the model.

[0209] Calculation example:

[0210] Assume the following parameters:

[0211] , , , .

[0212] Calculation process:

[0213] calculate :

[0214] ;

[0215] Assumptions .

[0216] Calculate contribution rate :

[0217] ;

[0218] The natural logarithm is used in the calculation process, and the obtained The value is about 0.49, indicating that the contribution of this pollution source to groundwater pollution is 49%. This shows that this pollution source has a significant impact on groundwater, but it is not the only source of pollution.

[0219] See also Figure 7 , the method for evaluating the impact range of differentiated pollution sources is:

[0220] S411: Collect groundwater flow data, including flow direction and velocity, and identify the distance between the pollution source and the dominant groundwater channel by marking the location of the pollution source on the map to obtain range association data;

[0221] S412: Based on the range association data, through the formula:

[0222] ;

[0223] Calculate the impact of pollutants ,in, is the impact range of the pollutant, is the diffusion coefficient, is the groundwater flow velocity, It's time. is the straight-line distance from the pollution source to the dominant groundwater channel, is the groundwater penetration depth coefficient, is the base of natural logarithms.

[0224] formula:

[0225] ;

[0226] Parameter details and how to obtain them:

[0227] : The diffusion coefficient, taking into account the diffusion performance of pollutants in underground media, reflects the migration ability of pollutants: usually obtained from laboratory tests or field tests, and typical values ​​can also be found in relevant literature.

[0228] : Groundwater velocity, indicating the rate at which water flows through the formation: estimated through hydrogeological measurements or using hydrological models.

[0229] : The duration from the beginning of the pollution incident to the present, determined based on the records of the pollution incident.

[0230] : The straight-line distance from the pollution source to the dominant groundwater path, measured using GIS technology.

[0231] : The coefficient of groundwater penetration depth reflects the permeability characteristics of the stratum. It is obtained through geological surveys or typical values ​​are obtained from related research. It can also be set by experts based on geology.

[0232] Calculation example:

[0233] Assume the following parameters:

[0234] : Diffusion coefficient.

[0235] :time.

[0236] : Groundwater flow rate, in meters per day.

[0237] : The distance from the pollution source to the assessment point, in meters.

[0238] : Groundwater penetration depth coefficient.

[0239] New calculation process:

[0240] Calculate the diffusion distance:

[0241] ;

[0242] What you get The value is about 542.78 meters, which means that within 10 days, the pollutants will migrate and spread about 542.78 meters in the groundwater. The potential impact area of ​​the pollutants has been significantly expanded, and rapid response measures are needed to prevent further environmental impacts.

[0243] See also Figure 8 , the steps to obtain the pollution source assessment results are:

[0244] S421: Classify pollutants released by differentiated pollution sources, record the chemical types and physical and chemical properties of pollutants, and obtain pollutant-related data;

[0245] S422: Based on pollutant association data and pollutant impact range , through the formula:

[0246] ;

[0247] Calculating pollution severity ,in, It is a pollutant The concentration of It is a pollutant The scope of influence, It is a pollutant The toxicity threshold is the distance decay factor, is the base of natural logarithms, The severity of pollution, is the number of pollutant types;

[0248] S423: Based on the severity of pollution , integrate the groundwater pollution contribution assessment results to obtain the pollution source assessment results.

[0249] formula:

[0250] ;

[0251] Parameter details and how to obtain them:

[0252] :The number of pollutant types involved in the calculation is obtained through on-site investigation and water quality analysis report statistics.

[0253] : Pollutants The concentration in groundwater is quantified using chemical analysis or spectroscopic analysis methods based on water quality monitoring data.

[0254] : The impact range corresponding to the pollutant is calculated through the previous steps.

[0255] : Pollutants Toxicity thresholds are used to guide the potential harm of pollutants to the environment or human health when they reach or exceed these values, which can be obtained from environmental protection standards or scientific literature.

[0256] : A factor used to adjust the attenuation effect, which represents the degree of attenuation of pollutant concentration in groundwater with distance, and is preset through geological and hydrological studies.

[0257] Calculation example:

[0258] Assumed parameters:

[0259] : Three different pollutants are involved in the calculation.

[0260] mg / L, mg / L, mg / L: Concentrations of three pollutants.

[0261] m, m, m: The impact range of the pollutant.

[0262] mg / L, mg / L, mg / L: Toxicity thresholds of three pollutants.

[0263] : distance attenuation factor.

[0264] Calculation process:

[0265] ;

[0266] Calculated The value is about 570.32, which is a comprehensive indicator that reflects the potential impact and degree of harm of the three pollutants on the groundwater environment. The value indicates that the pollution is serious and measures need to be taken to control it.

[0267] A mixed zone groundwater pollution source tracing identification system based on multiple means, a mixed zone groundwater pollution source tracing identification system based on multiple means is used to execute the mixed zone groundwater pollution source tracing identification method based on multiple means, the system comprises;

[0268] The potential pollution source identification module evaluates the risk of raw material leakage in factories around the contaminated area based on the groundwater contamination area, and evaluates the pollution risk according to the operating conditions of the factory's wastewater treatment and solid waste management facilities to obtain a list of potential pollution sources;

[0269] The key pollution source identification module is based on the potential pollution source list and the characteristic molecular compounds in the groundwater samples at the detection point and the potential pollution source samples to establish the pollution characteristic fingerprint of the sample. By comparing the similarity of the pollution characteristic fingerprints of the detection point and the potential pollution source, the pollution source is identified and the key pollution source identification information is obtained;

[0270] The pollution contribution analysis module analyzes the isotopic composition of groundwater and pollution sources based on the identification information of key pollution sources, and calculates the contribution rate of differentiated pollution sources to groundwater pollution by combining the probabilistic isotope mixing model to obtain the groundwater pollution contribution assessment results;

[0271] The pollution impact assessment module evaluates the impact range of differentiated pollution sources based on the groundwater pollution contribution assessment results, according to the groundwater runoff direction and the location of the pollution source, and obtains the impact range assessment results;

[0272] The pollution risk assessment module evaluates the severity of pollution based on the impact scope assessment results, according to the type, concentration and physical and chemical properties of pollutants, and obtains the pollution source tracing assessment results;

[0273] 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 tracing and identifying the source of groundwater pollution in mixed areas based on multiple means, characterized in that: The following steps are involved: Based on the groundwater pollution area, detect the raw material storage, transportation and use processes of factories in multiple pollution mixed areas, evaluate the risk of raw material leakage, and evaluate the pollution risk of differentiated factories according to the operation status of the factory's wastewater treatment and solid waste management facilities to obtain a list of potential pollution sources; The method for assessing the risk of raw material leakage is: Based on the groundwater pollution area, collect data on the storage, transportation and use of raw materials in factories in mixed pollution areas to obtain data related to raw material leakage; Based on the raw material leakage correlation data, through the formula: ； Calculate the raw material leakage risk index ,in, Represents the danger of raw materials, Indicates the storage security measure score, Indicates the score of transportation safety measures, Indicates the degree of environmental impact, is the adjustment parameter, and is the weight coefficient, is the environmental impact adjustment factor, is the raw material leakage risk index; Based on the raw material leakage risk index ,according to The value is used to evaluate the leakage risk and obtain the leakage risk assessment result; The steps for obtaining the potential pollution source list are: Based on the raw material leakage risk index , collect operational data of the factory’s wastewater treatment and solid waste management facilities, including wastewater treatment volume, wastewater treatment efficiency, and solid waste discharge; Based on the operating data, the formula: ； Calculate the pollution risk index for each factory ,in, is the raw material leakage risk index, is the wastewater treatment volume, For wastewater treatment efficiency, For solid waste management emission levels, and is the adjustment factor, is the pollution risk index; Based on the contamination risk index , compared with the preset pollution risk threshold, Factories whose values ​​exceed the preset pollution risk threshold are marked as potential pollution sources, and a list of potential pollution sources is obtained; Based on the list of potential pollution sources, the pollution characteristic fingerprint of the sample is established according to the characteristic molecular compounds in the groundwater samples of the detection point in the mixing area and the samples of the surrounding potential pollution sources. By comparing the pollution characteristic fingerprints of the detection point and the potential pollution source, the similarity of the pollution characteristic fingerprint is evaluated, the pollution source is identified, and the key pollution source identification information is obtained; Based on the key pollution source identification information, the contribution rate of differentiated pollution sources to groundwater pollution is calculated by analyzing the isotopic composition of groundwater and pollution sources and combining the probabilistic isotope mixing model to obtain the groundwater pollution contribution assessment result; Based on the groundwater pollution contribution assessment results, combined with the groundwater runoff direction and the location of the pollution source in the mixed pollution area, the impact range of the differentiated pollution sources is assessed, and the severity of the pollution is assessed according to the type, concentration and physical and chemical properties of the pollutants to obtain the pollution source tracing assessment results; The method for evaluating the impact range of differentiated pollution sources is: Collect groundwater flow data, including flow direction and velocity, and obtain range correlation data by marking the location of pollution sources on the map and identifying the distance between pollution sources and dominant groundwater channels; Based on the range associated data, by the formula: ； Calculate the impact of pollutants ,in, is the impact range of the pollutant, is the diffusion coefficient, is the groundwater flow velocity, It's time. is the straight-line distance from the pollution source to the dominant groundwater channel, is the groundwater penetration depth coefficient, is the base of natural logarithms; The steps for obtaining the pollution source tracing assessment results are as follows: Classify pollutants released by differentiated pollution sources, record the chemical types and physical and chemical properties of pollutants, and obtain pollutant-related data; Based on the pollutant association data and the impact range of the pollutants , through the formula: ； Calculating pollution severity ,in, It is a pollutant The concentration of It is a pollutant The scope of influence, It is a pollutant The toxicity threshold is the distance decay factor, is the base of natural logarithms, The severity of pollution, is the number of pollutant types; Based on the severity of the pollution , integrate the groundwater pollution contribution assessment results to obtain the pollution source tracing assessment results.

2. The method for tracing and identifying the source of groundwater pollution in mixed areas based on multiple means according to claim 1 is characterized in that: The method for establishing the pollution characteristic fingerprint of the sample is: Based on the list of potential pollution sources, samples are collected from groundwater detection points and potential pollution sources, and characteristic molecular compounds in the samples are analyzed by ultra-high performance liquid chromatography-high resolution time-of-flight mass spectrometry and gas chromatography-mass spectrometry, wherein the characteristic molecular compounds include drugs, pesticides, veterinary drugs, personal care products, industrial chemicals, plasticizers and flame retardants, and the concentrations of the characteristic molecular compounds are detected to obtain characteristic molecular compound data; Based on the characteristic molecular compound data, the formula: ； Calculate the contamination signature fingerprint of the sample ,in, is the total number of compounds detected, It is The weight coefficient of the compound, For the The concentration of the compound, For the The coefficient of variation of the compound, It is the pollution characteristic fingerprint.

3. The method for tracing and identifying the source of groundwater pollution in mixed areas based on multiple means according to claim 2 is characterized in that: The steps for obtaining the key pollution source identification information are as follows: Based on the pollution characteristic fingerprint , the sample feature fingerprint of the detection point Sample characteristic fingerprints with potential contamination sources For comparison, use the formula: ； Calculating Similarity ,in, For the The weight coefficient of the test, For the The characteristic fingerprint of the sample at the detection point in the detection, For the The characteristic fingerprint of the potential contamination source samples in the first test, is the number of detections, for similarity; Based on the similarity , compared with the preset similarity threshold, the pollution sources exceeding the similarity threshold are marked as key pollution sources, and the key pollution source identification information is obtained.

4. The method for tracing and identifying the source of groundwater pollution in mixed areas based on multiple means according to claim 1 is characterized in that: The steps for obtaining the groundwater pollution contribution assessment results are as follows: Based on the key pollution source identification information, isotope tracer samples are collected from groundwater monitoring points and designated pollution sources, and isotope tracer analysis is performed to obtain isotope data of groundwater samples and pollution source samples; Based on the isotope data of the groundwater samples and pollution source samples, the formula: ； Calculate the logarithmic difference of isotope ratios ,in, is the isotope ratio in the groundwater sample, is the isotope ratio in the pollution source sample, is the logarithmic difference of isotope ratios; Based on the logarithmic difference of the isotope ratios , through the formula: ； Calculate pollution contribution rate , and according to The value is combined with the probabilistic isotope mixing model to evaluate the contribution of differentiated pollution sources to groundwater pollution and obtain the groundwater pollution contribution assessment results, among which, is the logarithmic difference of the isotope ratios, The pollution contribution rate is is the largest isotopic difference, is the stability constant, is the index parameter.

5. The mixed zone groundwater pollution source identification system based on multiple means is characterized by: According to the method for tracing and identifying the source of groundwater pollution in a mixed zone based on multiple means according to any one of claims 1 to 4, the system comprises: The potential pollution source identification module evaluates the risk of raw material leakage in factories around the contaminated area based on the groundwater contamination area, and evaluates the pollution risk according to the operating conditions of the factory's wastewater treatment and solid waste management facilities to obtain a list of potential pollution sources; The key pollution source identification module establishes the pollution characteristic fingerprint of the sample based on the potential pollution source list and the characteristic molecular compounds in the groundwater sample at the detection point and the potential pollution source sample, identifies the pollution source by comparing the similarity between the pollution characteristic fingerprints of the detection point and the potential pollution source, and obtains the key pollution source identification information; The pollution contribution analysis module analyzes the isotopic composition of groundwater and pollution sources based on the key pollution source identification information, and calculates the contribution rate of differentiated pollution sources to groundwater pollution by combining the probabilistic isotope mixing model to obtain the groundwater pollution contribution assessment result; The pollution impact assessment module evaluates the impact range of the differentiated pollution sources based on the groundwater pollution contribution assessment result and the groundwater runoff direction and the location of the pollution source to obtain an impact range assessment result; The pollution risk assessment module evaluates the severity of the pollution based on the impact scope assessment results and according to the type, concentration and physical and chemical properties of the pollutants to obtain the pollution source tracing assessment results.

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