Early warning grade evaluation method based on urban pollution industrial site

Abstract

The invention discloses an early warning grade evaluation method based on an urban pollution industrial site, relates to the technical field of industrial site early warning evaluation, and solves the technical problems of incomplete overall evaluation and lack of systematic analysis process and data processing correction caused by analysis of a single evaluation index. According to the method, pollution factor indexes are integrated in a three-dimensional mode through the pollutant standard exceeding multiple mean value, the specific pollutant toxicity coefficient and the pollution plume diffusion area proportion, the pollution intensity is reflected, toxicity hazards and spatial diffusion risks are considered, the soil pollution area is calculated through the Kriging interpolation method, the groundwater pollution plume area is predicted through the MODFLOW model, and the groundwater pollution plume area is predicted through the MODFLOW model. The overlapping area is processed through a maximum area method, repeated statistics is avoided, the accuracy of pollution range data is improved, different threshold values are set, standardized matching of comprehensive indexes and early warning levels is achieved, corresponding management and control measures are defined for all the early warning levels, abstract comprehensive indexes are converted into specific practical operation guidance, and hierarchical management and control can be conveniently carried out.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of early warning evaluation of industrial sites, in particular to an early warning grade evaluation method based on urban pollution industrial sites. BACKGROUND

[0002] With the adjustment of industrial structure, a large number of urban pollution industrial sites left by relocated or closed industrial enterprises have become an important hidden danger to urban environmental safety. Such sites generally have characteristics such as complex types of pollutants, large differences in pollution depth, and various migration paths. If not timely controlled, they are easy to threaten the health of surrounding residents and the safety of the ecological system through soil-groundwater-atmosphere exposure pathways.

[0003] Early methods mostly focus on the exceeding multiple of pollutant concentration, ignoring the synergistic effect of pollution migration and diffusion range, resulting in a biased judgment of pollution diffusion potential. Some methods only simply calculate the straight-line distance between the site and the sensitive target, without considering the particularity of linear facilities and the buffering effect of barrier screens. Moreover, the population density assessment mostly uses average density, without reflecting the gradient difference that the closer to the site, the higher the risk. The existing technology often evaluates human health risk and ecological risk separately, and the weight coefficient mostly depends on the subjective setting of the operator, lacking a standardized comprehensive index calculation process. At the same time, the corresponding relationship between the early warning grade and the control measures is ambiguous, making it difficult to directly guide the site emergency disposal or remediation engineering. SUMMARY

[0004] In view of the deficiencies of the prior art, the present application provides an early warning grade evaluation method based on urban pollution industrial sites, which solves the problems of incomplete overall evaluation caused by single evaluation index analysis, lack of systematic analysis process and data processing correction.

[0005] To achieve the above purpose, the present application is implemented by the following technical scheme: an early warning grade evaluation method based on urban pollution industrial sites, which specifically comprises the following steps: Step 1: Determine the urban pollution industrial site grade evaluation index through field sampling monitoring and historical data analysis, including pollution factor index, receptor sensitivity index and exposure risk index; Step 2: Analyze and process the pollution factor index, comprehensively analyze the pollution factor index from the average exceeding multiple of pollutants, the toxicity coefficient of characteristic pollutants and the area proportion of pollution plume diffusion, and obtain the pollution factor index by weighted summation; Step 3, analyze and process the receptor sensitivity index, analyze the receptor sensitivity index from the minimum distance of sensitive target and the surrounding population density, and obtain the receptor sensitivity index by weighted summation; Step 4, analyze and process the exposure risk index, evaluate and process the exposure risk index from human health risk and ecological risk, and obtain the exposure risk index by weighted summation; Step 5: Calculate a comprehensive index by weighting and summing the pollutant indicators, receptor sensitivity indicators, and exposure risk indicators, and match it with the evaluation criteria to generate an early warning level signal.

[0006] As a further aspect of the present invention, the calculation process of the average multiple of pollutant exceedance is as follows: obtain the measured concentration and corresponding standard limit of all pollutants that exceed the standard, calculate (measured concentration - standard limit) / standard limit of each pollutant that exceeds the standard, and take the average value of the ratio as the average multiple of pollutant exceedance.

[0007] As a further aspect of the present invention, the calculation process of the pollution plume diffusion area ratio is as follows: the soil pollution contour lines are drawn using the Kriging interpolation method and the area of ​​the soil exceeding the standard is counted. The groundwater pollution plume area is predicted based on the MODFLOW model, and the total pollution area and the pollution plume diffusion area ratio R are calculated. If the soil exceeding the standard area and the groundwater pollution plume have planar overlap, the total pollution area is calculated using the maximum area method.

[0008] As a further aspect of the present invention, the area of ​​the soil exceeding the standard is the maximum horizontal projection area of ​​the exceeding area in the surface soil and deep soil; the area of ​​the groundwater pollution plume is the planar distribution area of ​​the pollution plume predicted based on the exceeding data of groundwater monitoring wells and hydrogeological parameters.

[0009] As a further aspect of the present invention, the weighted summation method for obtaining the receptor sensitivity index is as follows: Obtain the straight-line distance from the site boundary to the nearest sensitive target, and then standardize it to obtain the minimum distance coefficient of the sensitive target, denoted as L. total Specifically, this is obtained by calculating the ratio of the straight-line distance to the maximum distance. For the surrounding population density, the population and corresponding area within a radius D are obtained, and the resulting area is divided into different regions. Simultaneously, the population per unit area for each region is calculated, and this value is standardized and denoted as the surrounding population density coefficient, denoted as P. coeff ; The obtained minimum distance coefficient L of the sensitive target total and the surrounding population density coefficient P coeff The receptor sensitivity index is obtained by weighted summation, according to the formula S=L total ×W L +P coeff ×W P The receptor sensitivity index S is calculated, where W L and W P These are the corresponding weighting coefficients, and the specific values ​​are set by the operator.

[0010] As a further aspect of the present invention, the specific method for obtaining the exposure risk index is as follows: For human health risk, the carcinogenic risk is analyzed, the carcinogenic species corresponding to the pollutants is judged, if it is a single species, the corresponding carcinogenic risk is calculated according to the formula carcinogenic risk = exposure dose x carcinogenic slope factor, if the carcinogenic species is multiple, the sum of the carcinogenic risks of all carcinogenic species is calculated to obtain the carcinogenic risk coefficient Y; For ecological risk, the formula is used to judge the harmful species corresponding to the pollutants, if it is a single species, the ecological risk quotient is calculated according to the formula ecological risk quotient = measured concentration of pollutants / ecological benchmark value, if it is multiple, the sum of the ecological risk quotients of all harmful species is calculated to obtain the ecological risk coefficient E; The obtained carcinogenic risk coefficient Y and ecological risk coefficient E are weighted and summed, and the formula K = Y x W Y + E x W E is used to obtain the exposure risk index, wherein W Y and W E are corresponding weight coefficients, and the specific values are set by the operator.

[0011] As a further scheme of the present application, the way of calculating the comprehensive index is: The obtained pollution factor index, receptor sensitivity index and exposure risk index are weighted and summed, and the formula ER = F x a1 + S x a2 + K x a3 is used to calculate the comprehensive index ER of the urban pollution industrial site, wherein a1, a2 and a3 are corresponding weight coefficients, and the specific values are set by the operator.

[0012] As a further scheme of the present application, the way of generating the early warning level signal is: If the comprehensive index ER is greater than or equal to 0.7, a first-level early warning signal is generated, if 0.4 ≤ ER < 0.7, a second-level early warning signal is generated, if 0.2 ≤ ER < 0.4, a third-level early warning signal is generated, and if ER < 0.2, a fourth-level early warning signal is generated.

[0013] As a further scheme of the present application, the standardization process of the surrounding population density coefficient is: according to the formula is used for standardization, wherein x i is the population value per unit area of region i, x min and x max are the minimum and maximum population values per unit area respectively.

[0014] As a further scheme of the present application, the first-level early warning signal indicates that the risk significantly exceeds the acceptable level and needs to be intervened immediately, the second-level early warning signal indicates that the risk is close to the critical value and needs to be controlled within a limited period, the third-level early warning signal indicates that there is potential risk and needs to be strengthened, and the fourth-level early warning signal indicates that the risk is within the acceptable range and needs to be managed regularly.

[0015] This invention provides a method for evaluating early warning levels of polluted industrial sites in cities. Compared with existing technologies, it has the following advantages: This invention integrates pollution factor indicators from three dimensions: the average multiple of pollutant exceedance, the toxicity coefficient of characteristic pollutants, and the proportion of pollution plume diffusion area. This reflects both the intensity of pollution and the risks of toxicity and spatial diffusion. It uses the Kriging interpolation method to calculate the soil pollution area and the MODFLOW model to predict the groundwater pollution plume area. It also uses the maximum area method to handle overlapping areas, avoids double counting, and improves the accuracy of pollution range data. Using GIS tools, the distance from the site to the "core functional area boundary" of sensitive targets is calculated, and corrections are made for linear facilities and barriers to ensure that the actual exposure risk represented by the distance is more in line with the site conditions. Population areas are divided, and the population value per unit area of ​​each area is calculated and standardized to accurately reflect the positive correlation between distance, density and risk, and avoid underestimating or overestimating the risk of average density. The process clearly defines the extreme values ​​of the average exceedance multiple of pollutants, the correction rules for the distance to sensitive targets, and the pathway calculation of exposure doses, forming standardized operating procedures to reduce human operational differences. Although the weights in the basic steps are set by the operators, space is reserved for expansion through a combination of "analytic hierarchy process + entropy weighting method," which can reduce subjectivity and improve the rationality of indicator integration by combining objective data with expert experience. By setting different thresholds, a standardized match between comprehensive indicators and warning levels is achieved, and corresponding control measures are clearly defined for each warning level. This transforms abstract comprehensive indicators into specific practical operational guidelines, making it easier for environmental protection departments and site management entities to carry out tiered control. Attached Figure Description

[0016] Figure 1 This is a diagram illustrating the steps and methods of the present invention. Detailed Implementation

[0017] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0018] First Embodiment Please see Figure 1 This application provides a method for evaluating the early warning level of polluted industrial sites in cities, which specifically includes the following steps: Step 1: Through on-site sampling and monitoring, and analysis of historical data, determine the pollution characteristics of urban industrial sites. This includes pollutant identification, pollution intensity, and pollution mobility. Pollutant identification primarily involves identifying the main pollutants and classifying them according to toxicity and mobility, such as heavy metals like Cr. 6+ The study included: Pb, Cd; organic pollutants: benzene, polycyclic aromatic hydrocarbons, VOCs; inorganic pollutants: cyanide, nitrates. Pollution intensity represents the multiple by which pollutants exceed the standard in soil / groundwater. Pollution mobility represents the leaching coefficient of pollutants in soil and the dispersion coefficient in groundwater. At the same time, the study determined the grade evaluation indicators for urban polluted industrial sites, specifically including pollutant factor indicators, receptor sensitivity indicators, and exposure risk indicators, and analyzed and processed them respectively.

[0019] Step 2: Analyze and process the pollution factor indicators, specifically from three aspects: the average multiple of pollutant exceedance, the toxicity coefficient of characteristic pollutants, and the proportion of the pollution plume diffusion area. The average multiple of pollutant exceedance is calculated as follows: obtain all pollutants exceeding standards in urban polluted industrial sites, along with their corresponding measured concentrations and standard limits. The standard limits are determined based on the corresponding pollutant concentration indicators. Then, calculate the average of (measured concentration - standard limit) / standard limit for all exceeding pollutants to obtain the average multiple of pollutant exceedance. Extreme value standardization is then applied to obtain the pollutant exceedance coefficient, denoted as K. std Furthermore, the extreme value standard treatment is specifically obtained by calculating the ratio of the mean to the maximum pollutant exceedance multiple; For the toxicity coefficient of characteristic pollutants, it is obtained and denoted as T according to the corresponding technical guidelines for risk assessment of contaminated sites. total To determine the proportion of the pollution plume's diffusion area, the pollution area corresponding to all pollution exceeding the standard is obtained. Specifically, the Kriging interpolation method is used to draw soil pollution contour lines based on the sampling point pollution data, and the horizontal projection area of ​​the pollutant exceeding the standard area is calculated. It is necessary to distinguish between surface soil and deep soil and take the maximum value of the two. At the same time, the groundwater pollution plume area is obtained. Specifically, based on the pollution data of groundwater monitoring wells, combined with hydrogeological parameters such as groundwater flow direction and permeability coefficient, the planar distribution area of ​​the pollution plume is predicted by the MODFLOW model, and the sum of the two areas is calculated to obtain the total pollution area. If the soil pollution area and the groundwater pollution plume have planar overlap, the maximum area method is used for calculation. Then, the proportion of the total pollution area is calculated to obtain the pollution and diffusion area ratio R. The average value K of the pollutant exceedance multiple obtained std Characteristic pollutant toxicity coefficient T total The weighted summation of the pollution plume diffusion area R is calculated using the formula F=K. std ×W1+T totalThe pollution factor index is calculated by multiplying W1 by W2 and then by R by W3, where W1, W2, and W3 are the corresponding weight coefficients, and the specific values ​​are set by the operator.

[0020] Step 3: Analyze and process the receptor sensitivity indicators, specifically from two aspects: minimum distance to sensitive targets and surrounding population density. For the minimum distance to sensitive targets, obtain the straight-line distance from the site boundary to the nearest sensitive target. Specifically, use GIS spatial analysis tools to calculate the straight-line distance from the site boundary to the core functional area boundary of the nearest sensitive target, rather than the distance to the target's center point. Correct the straight-line distance. If the sensitive target is a linear facility, such as a riverbank in a drinking water source protection area, take the shortest vertical distance from the site boundary to the bank. If there is a barrier between the site and the sensitive target, such as a river ≥20m wide, a seepage-proof wall ≥5m high, or a dedicated railway line, the distance can be corrected according to the barrier's effectiveness. If effective barrier occurs, multiply the distance by 1.2 to weaken the direct impact. If the sensitive target has been relocated or is no longer in use, it is not included in the distance calculation. Standardize the distance to obtain the minimum distance coefficient for the sensitive target, denoted as L. total Specifically, this is achieved by calculating the ratio of the straight-line distance to the maximum distance. Based on the surrounding population density, the population and corresponding area within a radius D are obtained, with the radius D determined according to the maximum distance to the sensitive target. The resulting area is then divided into different regions, and the population per unit area for each region is calculated and standardized. The specific calculation is based on the formula... The values ​​are standardized, and the resulting values ​​are denoted as the surrounding population density coefficient and P. coeff Where i represents the region type, xi is the population per unit area corresponding to region i, and x min and x max These represent the minimum and maximum population per unit area, respectively. The obtained minimum distance coefficient L of the sensitive target total and the surrounding population density coefficient P coeff The receptor sensitivity index is obtained by weighted summation, according to the formula S=L total ×W L +P coeff ×W P The receptor sensitivity index S is calculated, where W L and W P These are the corresponding weighting coefficients, and the specific values ​​are set by the operator.

[0021] Step 4: Analyze the exposure risk indicators, specifically assessing them from two aspects: human health risk and ecological risk. For human health risk, analyze the carcinogenic risk and determine the type of carcinogen corresponding to the pollutant. If it is a single type, calculate the corresponding carcinogenic risk according to the formula: Carcinogenic Risk = Exposure Dose × Carcinogenic Slope Factor. If there are multiple types of carcinogens, calculate the sum of the carcinogenic risks of all types of carcinogens and obtain the carcinogenic risk coefficient, denoted as Y. Based on the formula, the type of hazard corresponding to the pollutant is determined according to the ecological risk. If it is a single type, the ecological risk quotient is calculated according to the formula: Ecological Risk Quotient = Measured Concentration of Pollutant / Ecological Baseline Value. If it is multiple types, the sum of the ecological risk quotients of all types of hazards is calculated to obtain the ecological risk coefficient E. The obtained carcinogenic risk coefficient Y and ecological risk coefficient E are weighted and summed according to the formula K=Y×W. Y +E×W E We obtained the exposure risk indicators, among which W Y and W E These are the corresponding weighting coefficients, and the specific values ​​are set by the operator.

[0022] Step 5: The obtained pollutant index, receptor sensitivity index, and exposure risk index are weighted and summed. Using the formula ER=F×a1+S×a2+K×a3, the comprehensive index ER of the urban polluted industrial site is calculated, where a1, a2+, and a3 are the corresponding weighting coefficients, with specific values ​​set by the operator. Next, the obtained comprehensive index ER is matched with the corresponding evaluation criteria, and the specific matching method is as follows: If the comprehensive indicator ER ≥ 0.7, a Level 1 warning signal is generated, indicating that the risk significantly exceeds the acceptable level and immediate intervention is required. If 0.4 ≤ ER < 0.7, a Level 2 warning signal is generated, indicating that the risk is approaching the critical value and control within a specified period is required. If 0.2 ≤ ER < 0.4, a Level 3 warning signal is generated, indicating that there is a potential risk and monitoring needs to be strengthened. If ER < 0.2, a Level 4 warning signal is generated, indicating that the risk is within the acceptable range and routine management is required.

[0023] Some of the data in the above formulas are numerical calculations with dimensions removed, and the contents not described in detail in this specification are all prior art known to those skilled in the art.

[0024] The above embodiments are only used to illustrate the technical methods of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical methods of the present invention without departing from the spirit and scope of the technical methods of the present invention.

Claims

1. A method for evaluating the warning level of an urban contaminated industrial site, characterized in that, The method specifically comprises the following steps: Step one: Determine the urban pollution industrial site grade evaluation index through field sampling monitoring and historical data analysis, including pollution factor index, receptor sensitivity index and exposure risk index; Step two: Analyze and process the pollution factor index, and comprehensively analyze from three aspects of pollution standard exceeding multiple average value, characteristic pollutant toxicity coefficient and pollution plume diffusion area proportion, and obtain the pollution factor index by weighted summation; Step three: Analyze and process the receptor sensitivity index, and analyze from two aspects of sensitive target minimum distance and surrounding population density, and obtain the receptor sensitivity index by weighted summation; Step four: Analyze and process the exposure risk index, and evaluate from two aspects of human health risk and ecological risk, and obtain the exposure risk index by weighted summation; Step five: Calculate the comprehensive index by weighted summation of the pollution factor index, the receptor sensitivity index and the exposure risk index, and match with the judgment standard to generate the early warning grade signal.

2. The method for evaluating the warning level of an urban contaminated industrial site according to claim 1, characterized in that, The calculation process of the pollution standard exceeding multiple average value is: the measured concentration and the corresponding standard limit value of all the exceeding pollution are obtained, (measured concentration-standard limit value) / standard limit value of each exceeding pollution is calculated, and the average value of the ratio is the pollution standard exceeding multiple average value.

3. The method for evaluating the warning level of an urban contaminated industrial site according to claim 1, characterized in that, The calculation process of the pollution plume diffusion area proportion is: the soil pollution contour is drawn by using the Kriging interpolation method, the soil exceeding area is counted, the groundwater pollution plume area is predicted based on the MODFLOW model, the total pollution area and the pollution plume diffusion area proportion R are calculated; if the soil exceeding area and the groundwater pollution plume exist plane overlap, the maximum area method is used to calculate the total pollution area.

4. The method for evaluating the warning level of an urban contaminated industrial site according to claim 3, characterized in that, The soil exceeding area is the maximum value of the horizontal projection area of the exceeding area in the surface soil and the deep soil; the groundwater pollution plume area is the plane distribution area of the pollution plume predicted based on the exceeding data of the groundwater monitoring well and the hydrogeological parameters.

5. The method for evaluating the warning level of an urban contaminated industrial site according to claim 1, characterized in that, The way of obtaining the receptor sensitivity index by weighted summation is: Obtain the straight line distance from the site boundary to the nearest sensitive target, and standardize it to obtain the minimum distance coefficient of the sensitive target, denoted as L total , Specifically, by calculating the ratio of the straight line distance to the maximum distance, for the surrounding population density, obtain the corresponding population number and the corresponding area within the radius D, and divide the obtained area into different regions, and calculate the corresponding unit area population value of different regions, and standardize it to obtain the surrounding population density coefficient, denoted as P coeff ; The obtained minimum distance coefficient L total and the peripheral population density coefficient P coeff are weighted and summed to obtain the receptor sensitivity index S, according to the formula S=L total ×W L +P coeff ×W P , wherein W L and W P are the corresponding weight coefficients, and the specific values are set by the operator.

6. The method for evaluating the warning level of an urban contaminated industrial site according to claim 1, wherein The specific way of obtaining the exposure risk index is: For human health risk, the carcinogenic risk is analyzed, the carcinogenic species corresponding to the pollution is judged, if it is a single species, the corresponding carcinogenic risk is calculated according to the formula carcinogenic risk=exposure dose×carcinogenic slope factor, if the carcinogenic species is multiple, the sum of the carcinogenic risks of all carcinogenic species is calculated to obtain the carcinogenic risk coefficient Y; For ecological risk, the harm species corresponding to the pollution is judged according to the formula, if it is a single species, the ecological risk quotient is calculated according to the formula ecological risk quotient=measured concentration of pollution / ecological benchmark value, if it is multiple, the sum of the ecological risk quotients of all harm species is calculated to obtain the ecological risk coefficient E; The obtained carcinogenic risk coefficient Y and ecological risk coefficient E are weighted and summed to obtain an exposure risk index K according to the formula K=Y×W Y +E×W E wherein W Y and W E are respective weight coefficients, and the specific values are set by the operator.

7. The method for evaluating the warning level of an urban contaminated industrial site according to claim 1, characterized in that, The way of calculating the comprehensive index is: The pollution factor index, the receptor sensitivity index and the exposure risk index are weighted and summed, and the comprehensive index ER of the urban pollution industrial site is calculated according to the formula ER=F×a1+S×a2+K×a3, wherein a1, a2 and a3 are the corresponding weight coefficients, and the specific values are set by the operator.

8. The method for evaluating the warning level of an urban contaminated industrial site according to claim 1, characterized in that, The way of generating the early warning grade signal is: If the comprehensive index ER is greater than or equal to 0.7, a first-level early warning signal is generated; if 0.4≤ER<0.7, a second-level early warning signal is generated; if 0.2≤ER<0.4, a third-level early warning signal is generated; and if ER<0.2, a fourth-level early warning signal is generated.

9. The method for evaluating the warning level of an urban contaminated industrial site according to claim 5, characterized in that, The standardization process of the peripheral population density coefficient is: according to the formula , wherein x i is the population value per unit area of the region i, x min and x max are the minimum and maximum population values per unit area respectively.

10. The method for evaluating the warning level of an urban contaminated industrial site according to claim 8, characterized in that, The first-level early warning signal indicates that the risk is significantly beyond the acceptable level and immediate intervention is required; the second-level early warning signal indicates that the risk is close to the critical value and needs to be controlled within a limited period; the third-level early warning signal indicates that there is potential risk and monitoring needs to be strengthened; and the fourth-level early warning signal indicates that the risk is within the acceptable range and is subject to regular management.

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