Pollution grade evaluation method and system based on VOCs in-situ detection while drilling technology and medium

Abstract

The invention provides a VOCs in-situ detection-while-drilling technology-based pollution grade evaluation method and system and a medium, the method comprises the steps of land parcel data collection and analysis, existing detection result analysis, VOCs in-situ detection-while-drilling and data comparative analysis processing, pollution grades are divided into high risks, medium risks and low risks, and according to whether VOCs in-situ detection-while-drilling carries GC-MS or not, the VOCs in-situ detection-while-drilling carries GC-MS, the VOCs in-situ detection-while-drilling carries GC-MS, and the VOCs in-situ detection-while-drilling carries GC-MS. The risk grade of an unknown investigation point location is comprehensively judged by correspondingly coupling a soil gas concentration nearest neighbor comparison method, a signal response nearest neighbor comparison method and a response grade division method, so that comprehensive quantitative judgment based on the signal data pollution grade is realized; according to the pollution level evaluation method based on the VOCs in-situ detection while drilling technology, the defects of multiple off-target points, multiple invalid points and multiple investigation rounds existing in a traditional investigation means mainly based on grid type system investigation are overcome, scientific guidance can be provided for layout of the investigation points, the reasonability of layout of the investigation points is improved, and the investigation efficiency is improved. And precise pollution identification is assisted.

Description

Technical Field

[0001] The present invention relates to the field of pollution detection technology, and in particular to a pollution level assessment method, system and medium based on VOCs in-situ detection while drilling technology. Background Art

[0002] VOCs in-situ detection while drilling technology can quickly collect soil gas in underground space through a semi-permeable membrane window, and quickly complete soil gas detection through the onboard PID, FID, XSD, ECD and other detectors, and obtain signal data after detection in real time. Compared with the traditional survey method of sampling at certain points and sending them to the laboratory for testing, VOCs in-situ detection while drilling technology can quickly identify contaminated areas, shorten the survey cycle, improve the survey accuracy, etc., and has strong application potential.

[0003] The signal data obtained through VOCs in-situ detection while drilling (WWD) technology provides a certain degree of insight into underground pollution, but signal data is not equivalent to pollutant concentration data. In existing technologies, after obtaining detection signal data, technicians often simply make subjective judgments based on the signal values ​​and their vertical variations. This lacks systematic and in-depth analysis, and lacks a quantitative basis for assessment, making it impossible to qualitatively determine the pollution level. This difficulty in interpreting signal data has, to a certain extent, hindered the further application of VOCs in-situ detection while drilling technology. Summary of the Invention

[0004] In view of the insufficient utilization of detection signal data obtained based on VOCs in-situ while-drilling detection technology in the existing technology, the difficulty in interpreting signal data and the evaluation problems, the purpose of the present invention is to propose a pollution level classification method that couples the nearest neighbor comparison method, the response level classification method and other comprehensive judgments to achieve comprehensive quantitative judgment of pollution levels based on signal data.

[0005] According to a first aspect of the present invention, a pollution level assessment method based on VOCs in-situ detection while drilling technology is proposed, comprising the following steps:

[0006] Step 1: Based on the land data collection, build a database of potential volatile organic pollutants in the land;

[0007] Step 2: Based on the historical test results of the plot and the soil pollution occurrence evaluation standards of the site environmental survey, obtain the comprehensive pollution index of soil volatile organic pollutants and the single pollution index of soil pollution, and determine the comprehensive pollution index and single pollution index of each point;

[0008] Step 3: Obtain signal data obtained by conducting VOCs in-situ while-drilling detection at target points within the plot;

[0009] Step 4: Based on the detector selected for VOCs in-situ detection while drilling, screen the VOCs in-situ detection while drilling technology measurable factors from the inventory of potential volatile organic pollutants in the plot. Identify the type of volatile organic pollutants by analyzing the different response levels of different detectors and the different responses of different detectors at the same depth;

[0010] Step 5: Based on the acquired signal data and the types of volatile organic pollutants, the risk level of the survey points is assessed according to whether the VOCs in-situ drilling detection equipment is equipped with GC-MS:

[0011] For VOCs in-situ drilling detection equipment equipped with GC-MS, soil gas collected at the highest response depth of the detector is qualitatively and quantitatively tested using GC-MS. Based on the obtained soil gas concentration data, the risk level is determined using the nearest neighbor comparison method of soil gas concentration.

[0012] For VOCs in-situ drilling detection equipment without GC-MS, the risk level of the survey point is determined based on the signal response nearest neighbor comparison method and the response level classification method;

[0013] Step 6: For any survey point, if it is determined to be at a high risk level based on any one of the soil gas concentration nearest neighbor comparison method, the signal response nearest neighbor comparison method, and the response level classification method, then the survey point is determined to be a high risk point. If any one of the methods determines that the pollution level of the survey point is at a high risk level, then no other method is used to determine the pollution level of the survey point; and

[0014] If the risk level is determined to be low based on any two or more of the soil gas concentration nearest neighbor comparison method, the signal response nearest neighbor comparison method, and the response level division method, the survey point is determined to be a low-risk point.

[0015] As an optional embodiment, in step 2, the soil volatile organic pollutant comprehensive pollution index P 综 is calculated as follows:

[0016]

[0017] In the formula, i represents the type of pollutant, especially the pollutants with a single pollution index greater than 0.3. It represents the maximum value of each pollution index in soil volatile organic pollutants. It represents the average value of each pollution index in soil volatile organic pollutants;

[0018] The soil pollution index P corresponding to each pollutant 单 is calculated as follows:

[0019]

[0020] Where C i Indicates the measured value of pollutants, S i is the standard value for pollutant evaluation.

[0021] As an optional embodiment, in step 2, the comprehensive pollution index of each point is calculated as follows:

[0022] The maximum value of the comprehensive pollution index at each point at different depths represents the comprehensive pollution index of the point, and the result is:

[0023]

[0024] Where n represents the depth.

[0025] Furthermore, the single pollution index of each point is calculated as follows:

[0026] The maximum value of the single pollution index at different depths for a specific pollutant in each position represents the single pollution index of the factor at that point, and the result is:

[0027]

[0028] Among them, n represents the sampling depth and i represents the type of pollutant.

[0029] As an optional embodiment, in step 5, for the VOCs in-situ detection while drilling equipment equipped with GC-MS, soil gas collected at the highest response depth of the detector is qualitatively and quantitatively detected using GC-MS, and based on the acquired soil gas concentration data, the risk level is determined using the soil gas concentration nearest neighbor comparison method, including:

[0030] Obtain soil concentration data and soil gas concentration data at known points, and calculate the concentration of all detected volatile pollutants according to the method in step 3. For unknown points, after obtaining the soil gas concentration data output by GC-MS qualitative and quantitative detection, compare it with the soil gas concentration data of the nearest known points, especially with known points with a single pollution index of soil volatile organic pollutants greater than 0.3:

[0031] If any volatility detected at an unknown point n1 represents a high risk coefficient, which is determined to be a high-risk point;

[0032] If all the volatility detected at unknown points n2 represents a low risk coefficient, which is determined to be a low risk point;

[0033] Other situations are judged as medium risk points.

[0034] Furthermore, when new volatile organic pollutants are detected by GC-MS qualitative and quantitative testing at unknown locations, and the concentration of the detected organic pollutants is less than or equal to 3-5 times the detection limit, the newly detected new volatile organic pollutants are considered to be at a low risk level;

[0035] When new volatile organic pollutants are detected by GC-MS qualitative and quantitative testing at an unknown point, and the concentration of the detected organic pollutants is greater than 3-5 times the detection limit, and the pollutants detected in the soil of nearby points have not been determined as high-risk points by the nearest neighbor comparison method of soil gas concentration, then the nearest neighbor comparison method of soil gas concentration is determined to be invalid for the detection of new volatile organic pollutants by GC-MS qualitative and quantitative testing at the unknown point, and it is necessary to further combine the signal response nearest neighbor comparison method and the response level classification method to determine the risk level of the survey point.

[0036] As an optional embodiment, in step 5, for VOCs in-situ drilling detection without GC-MS, the risk level of the survey point is determined based on the signal response nearest neighbor comparison method and the response level classification method, including:

[0037] Acquire signal data from in-situ VOCs detection while drilling without GC-MS, and use the nearest neighbor comparison method to make judgments. By comparing with the nearest neighbor points with acquired concentration and signal data, especially with known points with a comprehensive pollution index of volatile organic pollutants in soil greater than 0.3, the response level of the signal value at the new detection point is determined and the risk level is determined. Specifically,

[0038] (1) Compared with the nearest neighbor point, if the maximum signal value of the new detection point satisfies:

[0039]

[0040] Then, it is determined to be a high-risk point;

[0041] If the maximum signal value of the new detection point satisfies:

[0042] And the response distance of the increased signal value is greater than 0.1 to 0.2 meters;

[0043] Then, it is determined to be a high-risk point;

[0044] Wherein, k1 represents the first risk control threshold, which ranges from 1.2 to 1.5;

[0045] The signal value increment part refers to the maximum signal value increment being greater than or equal to part;

[0046] (2) Compared with the nearest neighbor point, if the maximum signal value of the new detection point satisfies:

[0047] And the response distance of the increased signal value is greater than 0.2 to 0.3 meters;

[0048] Then, it is determined to be a high-risk point:

[0049] Wherein, k2 represents the second risk control threshold, which ranges from 0.7 to 0.9;

[0050] The signal value increment part refers to the maximum signal value increment being greater than or equal to part;

[0051] (3) Compared with the nearest neighbor point, if the maximum signal value of the new detection point satisfies:

[0052]

[0053] Then, it is determined to be a low-risk point;

[0054] Among them, k3 represents the third risk control threshold, which ranges from 0.2 to 0.4;

[0055] (4) Other situations are determined to be medium-risk points.

[0056] As an optional embodiment, in step 5, for VOCs in-situ drilling detection equipment not equipped with GC-MS, the risk level of the survey point is determined based on the signal response nearest neighbor comparison method and the response level classification method, including:

[0057] Acquire the signal data obtained from VOCs in-situ detection while drilling without GC-MS, and use the response level classification method to determine the response level of the signal value at the new detection point and determine the risk level. Specifically,

[0058] The response level is set to 3 levels, including weak response, general response, and strong response;

[0059] For the detector signal data obtained from new detection points for VOCs in-situ drilling without GC-MS, the response level and risk level of the new detection point are determined based on the change in each detector signal data compared to the baseline and the maximum response signal value:

[0060] (1) If the signal data of each detector changes compared to the baseline and the maximum response signal value meets the following conditions, it is determined to be a weak response and a low-risk point:

[0061] Condition 1: Screening points where volatile organic pollutants are not detected or the detection concentration is less than or equal to 3-5 times the detection limit. The maximum increase in the signal data of each detector compared to the baseline and the maximum response signal value are used as the screening value. The maximum increase in the signal data of each detector and the maximum signal response value at the new detection point are both less than the screening value.

[0062] (2) If any detector signal data changes compared to the baseline and the maximum response signal value meets the following two conditions, it is determined to be a strong response and a high-risk point:

[0063] Condition 2: When screening points involving excessive levels of volatile organic pollutants, determine the maximum value of the increase in the value of each detector at each excessive point compared to the baseline and the maximum response signal value. The minimum value of the maximum value of the increase in the value of the maximum signal response among all excessive points is used as the screening value, and either the maximum value of the increase in the value of the signal data of the detector at the newly detected point or the maximum signal response value is greater than the screening value;

[0064] (3) Other situations can be considered as general responses and determined as medium-risk points.

[0065] According to a second aspect of the present invention, a computer system is provided, comprising:

[0066] one or more processors; and

[0067] Memory, which stores instructions that can be operated;

[0068] Among them, when the instruction is executed by one or more processors, the one or more processors mentioned above perform operations, and the operations include the process of executing the above-mentioned pollution level assessment method based on VOCs in-situ detection while drilling technology.

[0069] According to a third aspect of the present invention, a computer-readable storage medium is proposed for storing one or more programs, wherein the one or more programs include instructions or instruction sets that can be executed by one or more processors, and when the instructions or instruction sets are executed by one or more processors, they perform the process of the aforementioned pollution level assessment method based on VOCs in-situ detection while drilling technology.

[0070] In combination with the pollution level assessment method based on VOCs in-situ while drilling detection technology in the above embodiment of the present invention, the pollution level delineation problem based on signal data is solved, making the application significance of VOCs in-situ while drilling detection technology more significant. Specifically, in view of the shortcomings of traditional survey methods based on grid-type system surveys, such as many off-target points (non-exceeding-standard points), many invalid points (points within the exceeding-standard range), and many survey rounds, VOCs in-situ while drilling detection technology can provide scientific guidance for the layout of survey points, improve the rationality of the layout of survey points, and assist in accurate pollution identification.

[0071] It should be understood that all combinations of the foregoing concepts and the additional concepts described in more detail below, as long as such concepts are not mutually inconsistent, can be considered part of the inventive subject matter of this disclosure. In addition, all combinations of the claimed subject matter are considered part of the inventive subject matter of this disclosure.

[0072] The foregoing and other aspects, embodiments, and features of the present invention will be more fully understood from the following description in conjunction with the accompanying drawings. Other additional aspects of the present invention, such as features and / or beneficial effects of the exemplary embodiments, will become apparent from the following description or through practice of specific embodiments according to the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0073] The accompanying drawings are not intended to be drawn to scale. In the accompanying drawings, each identical or nearly identical component shown in various figures may be represented by the same reference numeral. For clarity, not every component is labeled in every figure. Embodiments of various aspects of the present invention will now be described by way of example and with reference to the accompanying drawings.

[0074] Figure 1 3 is a flow chart of a pollution level assessment method based on VOCs in-situ detection while drilling technology according to an embodiment of the present invention.

[0075] Figure 2 Schematic diagram of point distribution of a grid system survey according to an example of the present invention.

[0076] Figure 3 Schematic diagram of the principle of the nearest neighbor comparison method of soil gas concentration according to an example of the present invention.

[0077] Figure 4 is a schematic diagram of a detector response signal according to an example of the present invention.

[0078] Figure 5 FIG. 2 is a schematic diagram of determining a response level based on a detector response signal according to an example of the present invention.

[0079] Figure 6It is a schematic diagram of qualitatively identifying specific pollutants using a VOCs in-situ while-drilling detector equipped with GC-MS according to an example of the present invention. DETAILED DESCRIPTION

[0080] In order to better understand the technical content of the present invention, specific embodiments are given below in conjunction with the accompanying drawings.

[0081] Various aspects of the present invention are described in this disclosure with reference to the accompanying drawings, in which a number of illustrative embodiments are shown. The embodiments of the present disclosure are not necessarily intended to include all aspects of the present invention. It should be understood that the various concepts and embodiments introduced above, as well as those described in more detail below, can be implemented in any of many ways, because the concepts and embodiments disclosed herein are not limited to any embodiment. In addition, some aspects of the present disclosure may be used alone or in any appropriate combination with other aspects disclosed herein.

[0082] {Example 1}

[0083] Combine Figure 1 As shown, the pollution level assessment method based on VOCs in-situ detection while drilling technology according to an embodiment of the present invention includes the following steps:

[0084] Step 1: Based on the collection of plot data, a database of potential volatile organic pollutants in the plot is constructed;

[0085] Step 2: Based on the historical test results of the plot and the soil pollution occurrence evaluation standards of the site environmental survey, obtain the comprehensive pollution index of soil volatile organic pollutants and the single pollution index of soil pollution, and determine the comprehensive pollution index and single pollution index of each point;

[0086] Step 3: Obtain signal data obtained by conducting VOCs in-situ while-drilling detection at target points within the plot;

[0087] Step 4: Based on the detector selected for VOCs in-situ detection while drilling, screen the VOCs in-situ detection while drilling technology measurable factors from the inventory of potential volatile organic pollutants in the plot. By taking into account the different response levels of different detectors and the different responses of different detectors at the same depth, qualitatively or semi-qualitatively identify the type of volatile organic pollutants;

[0088] Step 5: Based on the acquired signal data and the types of volatile organic pollutants, the risk level of the survey points is assessed based on whether the VOCs in-situ detection while drilling system is equipped with GC-MS:

[0089] For VOCs in-situ drilling detection equipment equipped with GC-MS, soil gas collected at the highest response depth of the detector is qualitatively and quantitatively tested using GC-MS. Based on the obtained soil gas concentration data, the risk level is determined using the nearest neighbor comparison method of soil gas concentration.

[0090] For VOCs in-situ drilling detection equipment without GC-MS, the risk level of the survey point is determined based on the signal response nearest neighbor comparison method and the response level classification method;

[0091] Step 6: For any survey point, if it is determined to be at a high risk level based on any one of the soil gas concentration nearest neighbor comparison method, the signal response nearest neighbor comparison method, and the response level classification method, then the survey point is determined to be a high risk point. If any one of the methods determines that the pollution level of the survey point is at a high risk level, then no other method is used to determine the pollution level of the survey point; and

[0092] If the risk level is determined to be low based on any two or more of the soil gas concentration nearest neighbor comparison method, the signal response nearest neighbor comparison method, and the response level division method, the survey point is determined to be a low-risk point.

[0093] In the embodiment of the present invention, the detectors selected for the aforementioned VOCs in-situ while drilling detection include PID detectors, FID detectors, ECD detectors, and XSD detectors;

[0094] PID detector, used to detect aromatic hydrocarbons and double-bond chlorine-containing VOCs with ionization energy below 10.6 eV;

[0095] FID detector, used to detect volatile hydrocarbons (VOCs);

[0096] ECD detector for detecting polyhalogenated VOCs;

[0097] XSD detector for the detection of volatile halogenated organic compounds.

[0098] As an optional embodiment, in step 2, the soil volatile organic pollutant comprehensive pollution index P 综 is calculated as follows:

[0099]

[0100] In the formula, i represents the type of pollutant, especially the pollutants with a single pollution index greater than 0.3; It represents the maximum value of each pollution index in soil volatile organic pollutants. It represents the average value of each pollution index in soil volatile organic pollutants.

[0101] Furthermore, the soil pollution index P corresponding to each pollutant is 单 is calculated as follows:

[0102]

[0103] Where C i Indicates the measured value of pollutants, S i is the standard value for pollutant evaluation.

[0104] As an optional embodiment, in step 2, the comprehensive pollution index of each point is calculated as follows:

[0105] The maximum value of the comprehensive pollution index at each point at different depths represents the comprehensive pollution index of the point, and the result is:

[0106]

[0107] Among them, n represents the sampling depth.

[0108] Furthermore, the single pollution index of each point is calculated as follows:

[0109] The maximum value of the single pollution index at different depths for a specific pollutant at each point represents the single pollution index of the factor at that point, and the result is:

[0110]

[0111] Among them, n represents the sampling depth and i represents the type of pollutant.

[0112] As an optional embodiment, in step 5, for VOCs in-situ detection while drilling equipment equipped with GC-MS, soil gas collected at the highest response depth of the detector is qualitatively and quantitatively detected using GC-MS, and based on the acquired soil gas concentration data, the risk level is determined using the soil gas concentration nearest neighbor comparison method, including:

[0113] Obtain soil concentration data and soil gas concentration data at known points, and calculate the concentration of all detected volatile pollutants according to the method in step 3. For unknown points, after obtaining the soil gas concentration data output by GC-MS qualitative and quantitative detection, compare it with the soil gas concentration data of the nearest known point, especially for the case of GC-MS, use Compare with known points greater than 0.3:

[0114] If any volatility detected at an unknown point n1 represents a high risk coefficient, which is determined to be a high-risk point;

[0115] If all the volatility detected at unknown points n2 represents a low risk coefficient, which is determined to be a low risk point;

[0116] Other situations are judged as medium risk points.

[0117] In the embodiment of the present invention, the value of the high risk coefficient n1 is 0.8-1.0; the value of the low risk coefficient n2 is 0.2-0.4.

[0118] Furthermore, when new volatile organic pollutants are detected by GC-MS qualitative and quantitative testing at unknown sites (specifically, new volatile organic pollutants not found in soil testing at nearby sites), and the concentration of the detected organic pollutants is less than or equal to 3-5 times the detection limit, the newly detected new volatile organic pollutants are considered low-risk factors, and other factors (i.e., volatile organic pollutants detected by both GC-MS soil gas testing and laboratory soil testing) can be used to determine the level using the nearest neighbor soil gas concentration evaluation standard;

[0119] When new volatile organic pollutants are detected by GC-MS qualitative and quantitative testing at an unknown point, and the concentration of the detected organic pollutants is greater than 3-5 times the detection limit, and the pollutants detected in the soil of nearby points have not been determined as high-risk points by the nearest neighbor comparison method of soil gas concentration, then the nearest neighbor comparison method of soil gas concentration is determined to be invalid for the detection of new volatile organic pollutants by GC-MS qualitative and quantitative testing at the unknown point, and it is necessary to further combine the signal response nearest neighbor comparison method and the response level classification method to determine the risk level of the survey point.

[0120] It should be understood that for any given location, volatile organic pollutants detected by GC-MS are divided into pollutants not detected in the soil of nearby locations and pollutants detected in the soil of nearby locations. If a newly detected volatile organic pollutant is not detected in the soil of nearby locations and its concentration exceeds 3-5 times the detection limit, the risk level of this newly detected factor cannot be determined due to the lack of comparison data on the concentration of the relevant pollutant in the soil. Further determination is required in combination with the signal response nearest neighbor comparison method and the response level classification method.

[0121] In an embodiment of the present invention, for the volatile organic pollutants detected at the survey point, as long as one pollution factor is judged to be high risk through the soil gas nearest neighbor comparison method, then the point is judged to be a high-risk point. Therefore, if this point can be judged to be a high-risk point through other factors, then there is no need to pay attention to the concentration of the newly detected pollutants.

[0122] As an optional embodiment, in step 5, for VOCs in-situ drilling detection without GC-MS, the risk level of the survey point is determined based on the signal response nearest neighbor comparison method and the response level classification method, including:

[0123] Obtain signal data from in-situ VOCs detection while drilling without GC-MS. Use the nearest neighbor comparison method to make judgments. By comparing with the nearest neighbor points with acquired concentration and signal data, especially with known points with a comprehensive pollution index of volatile organic pollutants in soil greater than 0.3 (that is, when GC-MS is not equipped, use points with a comprehensive pollution index greater than 0.3 for comparison), determine the response level of the signal value at the new detection point and determine the risk level. The specific steps include:

[0124] (1) Compared with the nearest neighbor point, if the maximum signal value of the new detection point satisfies:

[0125]

[0126] Then, it is determined to be a high-risk point;

[0127] If the maximum signal value of the new detection point satisfies:

[0128] And the response distance of the increased signal value is greater than 0.1 to 0.2 meters;

[0129] Then, it is determined to be a high-risk point;

[0130] Wherein, k1 represents the first risk control threshold, which ranges from 1.2 to 1.5;

[0131] The signal value increment part refers to the maximum signal value increment being greater than or equal to part;

[0132] (2) Compared with the nearest neighbor point, if the maximum signal value of the new detection point satisfies:

[0133] And the response distance of the increased signal value is greater than 0.2 to 0.3 meters;

[0134] Then, it is determined to be a high-risk point:

[0135] Wherein, k2 represents the second risk control threshold, which ranges from 0.7 to 0.9;

[0136] The signal value increment part refers to the maximum signal value increment being greater than or equal to part;

[0137] (3) Compared with the nearest neighbor point, if the maximum signal value of the new detection point satisfies:

[0138]

[0139] Then, it is determined to be a low-risk point;

[0140] Among them, k3 represents the third risk control threshold, which ranges from 0.2 to 0.4;

[0141] (4) Other situations are determined to be medium-risk points.

[0142] As an optional embodiment, in step 5, for VOCs in-situ drilling detection without GC-MS, the risk level of the survey point is determined based on the signal response nearest neighbor comparison method and the response level classification method, including:

[0143] Acquire signal data from in-situ VOCs detection while drilling without GC-MS, and use the response level classification method to determine the signal value response level and risk level of the new detection point, specifically:

[0144] The response level is set to 3 levels, including weak response, general response, and strong response;

[0145] For the detector signal data obtained from new detection points for VOCs in-situ drilling without GC-MS, the response level and risk level of the new detection point are determined based on the change in each detector signal data compared to the baseline and the maximum response signal value:

[0146] (1) If the signal data of each detector changes compared to the baseline and the maximum response signal value meets the following conditions, it is determined to be a weak response and a low-risk point:

[0147] Condition 1: Screening points where volatile organic pollutants are not detected or the detection concentration is less than or equal to 3-5 times the detection limit. The maximum increase in the signal data of each detector compared to the baseline and the maximum response signal value are used as the screening value. The maximum increase in the signal data of each detector and the maximum signal response value at the new detection point are both less than the screening value.

[0148] (2) If any detector signal data changes compared to the baseline and the maximum response signal value meets the following two conditions, it is determined to be a strong response and a high-risk point:

[0149] Condition 2: When screening points involving excessive levels of volatile organic pollutants, determine the maximum value of the increase in the value of each detector at each excessive point compared to the baseline and the maximum response signal value. The minimum value of the maximum value of the increase in the value of the maximum signal response among all excessive points is used as the screening value, and either the maximum value of the increase in the value of the signal data of the detector at the newly detected point or the maximum signal response value is greater than the screening value;

[0150] (3) Other situations can be considered as general responses and determined as medium-risk points.

[0151] Thus, the method of the present invention can achieve comprehensive quantitative determination of pollution levels based on signal data by coupling the pollution level classification method of nearest neighbor comparison and response classification with a small amount of laboratory test data. Furthermore, based on the pollution level determination results of the survey points, a risk level point map can be drawn, providing a basis for the layout of drilling sampling points in subsequent plots and guiding plot survey work.

[0152] High-risk points indicate a high risk of exceeding the standard for volatile organic pollutants, while medium-risk points indicate a certain risk of exceeding the standard for volatile organic pollutants. The boundary of excessive pollution is generally located in the area where high-risk and medium-risk points are located. On the basis of meeting the requirements of existing survey guidelines, priority can be given to setting up survey points for drilling sampling and inspection in the intersection area of ​​high-risk and medium-risk points or in the medium-risk area (which may be the boundary of volatile organic pollution). Low-risk points indicate a low risk of exceeding the standard for volatile organic pollutants, and the layout of points in the area where low-risk points are located can be weakened. The above-mentioned classification of pollution levels can improve the scientificity and rationality of the investigation and help to more accurately identify pollution.

[0153] The method proposed in this invention is only aimed at the investigation of VOCs-contaminated plots. For the determination of the risk level of plots containing heavy metals or SVOCs composite pollution, geophysical detection, laser-induced fluorescence detection and other means can be combined to further determine the occurrence of other types of pollutants and derive a comprehensive pollution level.

[0154] {Example 2}

[0155] In this embodiment, further combined with the accompanying drawings, the implementation process of the pollution level assessment method based on the VOCs in-situ detection while drilling technology in the above embodiment is described in more detail.

[0156] The implementation process of the pollution level assessment method based on VOCs in-situ detection while drilling technology in this embodiment mainly includes plot data collection and analysis, analysis of existing test results, VOCs in-situ detection while drilling, and data comparison, analysis and processing. By classifying pollution levels into high risk, medium risk and low risk, the soil gas concentration nearest neighbor comparison method, signal response nearest neighbor comparison method, and response level classification method are used to comprehensively judge the risk level of unknown survey points.

[0157] For VOCs in-situ detection while drilling (LWD) technology without GC-MS, the risk level of survey points can be determined based on the nearest neighbor comparison method and response classification method. A high risk level indicates a high risk of exceeding soil contamination standards, a medium risk level indicates a moderate risk, and a low risk level indicates a low risk.

[0158] (1) Plot data collection and analysis: Collect information such as raw and auxiliary materials, production processes, hydrogeological survey reports, inspection reports, construction distribution, and plot vector boundaries of the survey plot and its surrounding adjacent plots, and comprehensively consider the plot's characteristic pollutants, potential migrating pollutants from surrounding plots, and volatile organic pollutants detected in the plot to construct a directory of potential volatile organic pollutants in the plot.

[0159] (II) Analysis of existing test results: Based on the survey results of the received plots, including: soil pollution status surveys of key industries and enterprises, self-monitoring by enterprises, detailed soil pollution investigations, monitoring around key regulatory units, and investigations of polluted plots, inorganic indicators, heavy metal indicators, semi-volatile organic indicators, and other indicators that the drill-down detectors did not respond to or had low sensitivity, were eliminated. With reference to the pollutant evaluation standards, the comprehensive pollution index of soil volatile organic pollutants (hereinafter referred to as the comprehensive pollution index, or P) was calculated in the following manner. 综 , C i is the measured value of pollutants, S i is the standard value for pollutant evaluation.

[0160] In the embodiment of the present invention, the pollutant evaluation standard value S i Based on the land use type, screening values ​​for Class I or Class II land use can be obtained from the "Soil Environmental Quality - Construction Land Soil Pollution Risk Control Standard" (GB 36600-2018) as evaluation criteria for the corresponding pollutants. Factors not covered by these standards can be obtained from corresponding local standards. Factors not mentioned in local standards can be calculated using existing risk assessment screening models.

[0161]

[0162] Thus, the comprehensive pollution index of volatile organic pollutants is obtained, which reflects the overall volatile organic pollution situation in the soil. In the above formula, i represents the type of pollutant (especially the pollutants with a single pollution index greater than 0.3 at the location of the volatile organic pollutants). It represents the maximum value of each pollution index in soil volatile organic pollutants. It represents the average value of each pollution index in soil volatile organic pollutants.

[0163] The soil pollution single pollution index, referred to as the single pollution index, is calculated according to the following formula: 单 :

[0164]

[0165] (3) Calculate the comprehensive pollution index of each point. The maximum value of the comprehensive pollution index at different depths is used to represent the comprehensive pollution index of each point.

[0166]

[0167] Similarly, the single pollution index of a specific pollutant at each point is calculated. The maximum value of the single pollution index at different depths for a specific pollutant at each point represents the single pollution index of the factor at that point, and the result is:

[0168]

[0169] (IV) Preliminary exploration of VOCs in-situ drilling detection technology: Based on the laboratory test data of soil samples at certain locations, the application of VOCs in-situ drilling detection technology was carried out in areas where no VOCs were detected or the detection was less than 5 times the detection limit, and in areas where VOCs exceeded the standard.

[0170] Among them, the number of pollution points where VOCs were not detected or detected less than 5 times the detection limit should be no less than 3, and the number of points where VOCs exceeded the standard should be no less than 3.

[0171] (5) Qualitative identification of VOCs pollutants: Based on the detectors selected for VOCs in-situ detection while drilling technology, the measurable factors of VOCs in-situ detection while drilling technology are screened out from the directory of potential volatile organic pollutants in the plot. The types of pollutants are qualitatively or semi-qualitatively identified by the different response levels of different detectors and the different responses of different detectors at the same depth.

[0172] PID detector is used to detect VOCs with ionization energy lower than 10.6eV, such as aromatic hydrocarbons and double-bond chlorine compounds.

[0173] FID detector is used for volatile hydrocarbons such as methane, butane, and heptane, and has a wide detection factor.

[0174] ECD detector, suitable for the detection of polyhalogenated VOCs.

[0175] XSD detector, suitable for the detection of volatile halogenated organic compounds.

[0176] Based on data collection and actual testing, a capability list library covering all detectors of major volatile organic pollutants was constructed. Combined with the inventory library of potential volatile organic pollutants in the plots and the response of each detector, the main types of volatile organic pollutants at the survey points were qualitatively or semi-qualitatively identified.

[0177] The VOCs in-situ downhole detection technology equipped with GC-MS can qualitatively identify the specific pollutants through qualitative detection of soil gas.

[0178] The following is an exemplary representation of the recognition capability library (part) of each detector.

[0179]

[0180] (6) The pollution levels of the detection points are classified into high risk, medium risk, and low risk. The risk level of the unknown survey points is comprehensively determined using the soil gas concentration nearest neighbor comparison method, the signal response nearest neighbor comparison method, and the response level classification method. As mentioned above, a high risk level indicates a high risk of exceeding the soil pollution standard, a medium risk level indicates a certain risk of exceeding the soil pollution standard, and a low risk level indicates a low risk of exceeding the soil pollution standard.

[0181] For VOCs in-situ downhole detection equipment that is not equipped with GC-MS, the risk level of the survey point can be determined based on the signal response nearest neighbor comparison method and the response level classification method.

[0182] (7) Determination of soil gas concentration using the nearest neighbor comparison method.

[0183] In-situ VOCs detection while drilling (WWD) technology equipped with GC-MS requires soil gas sampling at the highest response depth of detectors such as PID, FID, ECD, and XSD, and qualitative and quantitative analysis using GC-MS. Based on the acquired soil gas concentration data, the risk level is determined using the nearest neighbor comparison method. Specifically, the GC-MS data from a new detection point is compared with the nearest neighbor point with existing soil concentration and GC-MS data to determine the contamination risk level at the new detection point.

[0184] As a specific example, the discrimination process is as follows:

[0185] Obtain soil concentration data and soil gas concentration data at known points, and calculate the concentration of all detected volatile pollutants according to the method in step 3 above.

[0186] Combined with attachment Figure 3 As shown in the figure, for unknown points, after obtaining the soil gas data output by GC-MS qualitative and quantitative detection, it is compared with the soil gas concentration data of the nearest known point to determine the risk level:

[0187] If any volatility detected at an unknown point n1 represents the high risk coefficient. In this example, the value is 0.8 to 1.0, which is considered a high risk point.

[0188] If all the volatility detected at unknown points n2 represents the low risk coefficient, which is 0.2 to 0.4 in this example and is considered a low risk point;

[0189] Other situations are judged as medium risk points;

[0190] When new volatile organic pollutants are detected by GC-MS qualitative and quantitative testing at unknown sites (specifically, new volatile organic pollutants that have not been found in soil testing at nearby sites), and the concentration of the detected organic pollutants is less than or equal to 3-5 times the detection limit, the newly detected new volatile organic pollutants are considered low-risk factors, and other factors (i.e., volatile organic pollutants detected by both GC-MS soil gas testing and laboratory soil testing) can be used to determine the level using the nearest neighbor soil gas concentration evaluation standard;

[0191] When new volatile organic pollutants are detected by GC-MS qualitative and quantitative detection at an unknown point, and the concentration of the detected organic pollutants is greater than 3-5 times the detection limit, and the pollutants detected in the soil at nearby points have not been determined as high-risk points by the nearest neighbor comparison method of soil gas concentration, then the nearest neighbor comparison method of soil gas concentration is determined to be invalid for the new volatile organic pollutants detected by GC-MS qualitative and quantitative detection at the unknown point, and it is necessary to further combine the response signal values ​​of detectors such as PID, FID, ECD, and XSD to further determine the pollution level.

[0192] (8) Signal response nearest neighbor comparison method judgment.

[0193] For VOCs in-situ while-drilling detection technology without GC-MS and for failures determined by the nearest neighbor comparison method of soil gas concentration, the pollution level is determined using the response signal data of each detector. Based on the signal data (response signals of each detector) obtained by VOCs in-situ while-drilling detection without GC-MS, the nearest neighbor comparison method of signal response is used to determine the response level of the signal value at the new detection point by comparing it with the nearest neighbor point with acquired concentration and signal data. This determines the risk level.

[0194] As a specific example, the discrimination process is as follows:

[0195] (1) If the maximum signal value of the newly detected point is significantly greater than that of the nearest neighbor point, Specifically refers to

[0196] k1 represents the first risk control threshold, ranging from 1.2 to 1.5;

[0197] Then, it is determined to be a high-risk point;

[0198] If the maximum signal value of the new detection point satisfies:

[0199] And the response distance of the increased signal value is greater than 0.1 to 0.2 meters;

[0200] Then, it is determined to be a high-risk point;

[0201] Among them, the signal value increase part refers to the maximum signal value increase greater than or equal to part;

[0202] (2) Compared with the nearest neighbor point, if the maximum signal value of the new detection point increases by Equivalent to or slightly reduced, specifically:

[0203] Moreover, the response distance of the part where the signal value increases is greater than 0.2 to 0.3 meters;

[0204] Then, it is determined to be a high-risk point:

[0205] Wherein, k2 represents the second risk control threshold, which ranges from 0.7 to 0.9;

[0206] The signal value increment part refers to the maximum signal value increment being greater than or equal to

[0207] (3) If the maximum signal value of the newly detected point is significantly less than that of the nearest neighbor point, Specifically:

[0208]

[0209] Then, it is determined to be a low-risk point;

[0210] Among them, k3 represents the third risk control threshold, which ranges from 0.2 to 0.4;

[0211] (4) Other situations are determined to be medium-risk points.

[0212] (9) Determination by response level classification method.

[0213] Combine Figure 4 、 5 As shown in the figure, for VOCs in situ downhole detection without GC-MS, the risk level of the survey point is determined based on the signal response nearest neighbor comparison method and the response grade classification method. Specifically, based on the signal data (response signals of each detector) obtained by VOCs in situ downhole detection without GC-MS, the response grade classification method is used to determine the response level of the signal value of the new detection point and determine the risk level.

[0214] As a specific example, the discrimination process is as follows:

[0215] The response level is set to 3 levels, including weak response, general response, and strong response;

[0216] For the detector signal data obtained from new detection points for VOCs in-situ while-drilling detection without GC-MS, the response level and risk level of the new detection points are determined based on the change in each detector signal data compared to the baseline and the maximum response signal value:

[0217] (1) If the signal data of each detector changes compared to the baseline and the maximum response signal value meets the following conditions, it is determined to be a weak response and a low-risk point:

[0218] Condition 1: Screening points where volatile organic pollutants are not detected or the detection concentration is less than or equal to 3-5 times the detection limit. The maximum increase in the signal data of each detector compared to the baseline and the maximum response signal value are used as the screening value. The maximum increase in the signal data of each detector and the maximum signal response value at the new detection point are both less than the screening value.

[0219] (2) If any detector signal data changes compared to the baseline and the maximum response signal value meets the following two conditions, it is determined to be a strong response and a high-risk point:

[0220] Condition 2: When screening points involving excessive levels of volatile organic pollutants, determine the maximum value of the increase in the value of each detector at each excessive point compared to the baseline and the maximum response signal value. The minimum value of the maximum value of the increase in the value of the maximum signal response among all excessive points is used as the screening value, and either the maximum value of the increase in the value of the signal data of the detector at the newly detected point or the maximum signal response value is greater than the screening value;

[0221] (3) Other situations can be considered as general responses and determined as medium-risk points.

[0222] (10) Finally, if the risk level is determined to be high by any of the above-mentioned methods such as the nearest neighbor comparison method of soil gas concentration, the nearest neighbor comparison method of signal response, and the response level classification method, then the survey point is determined to be a high-risk point; if the risk level is determined to be low by any two or more of the above-mentioned methods such as the nearest neighbor comparison method of GC-MS detection data, the nearest neighbor comparison method of signal data, and the response level classification method, then the survey point is determined to be a low-risk point; the rest of the cases are medium-risk levels.

[0223] It should be understood that for the volatile organic pollutants detected at the survey points, as long as one pollution factor is judged to be high risk through the soil gas nearest neighbor comparison method, then the point is judged to be a high-risk point. Therefore, if this point can be judged to be a high-risk point through other factors, then there is no need to pay attention to the concentration of the newly detected pollutants.

[0224] {Example 3}

[0225] In this example, we applied VOCs in-situ drilling detection technology to a retired plot of land in a certain city based on the method of the previous example. By collecting soil pollution status survey data and comprehensively analyzing information such as raw and auxiliary materials, production processes, etc. of the surveyed plot and surrounding plots, we constructed a directory of potential volatile organic pollutants for the plot, which mainly includes benzene series such as benzene and toluene, and chlorinated alkanes such as 1,2-dichloroethane.

[0226] PID, FID, and XSD detectors were used to collaboratively detect 43 points on site. GC-MS-connected VOCs in-situ downhole detectors were used simultaneously at 13 points to measure soil gas concentrations in high-response areas (involving 4 points where laboratory test data had been obtained).

[0227] At some points, PID and FID responded synergistically while XSD did not respond, indicating the presence of benzene pollution; at some points, FID and XSD responded but PID did not respond, indicating the presence of chlorinated hydrocarbon pollutants. After drilling and analysis, the results were consistent with the inferred results.

[0228] The qualitative detection of soil gas was completed using VOCs in-situ drilling detection equipment equipped with GC-MS, and the specific pollutants were qualitatively identified, including toluene, 1,2-dichloroethane, etc. Figure 6 As shown, the results are basically consistent with the detection and analysis of actual soil samples.

[0229] In this embodiment, soil gas concentration data was obtained by using an in-situ VOCs downhole detector equipped with GC-MS. According to the soil gas concentration nearest neighbor comparison method in the seventh step, 5 of the 9 unknown points were determined to be high-risk points, 1 was determined to be a low-risk point, and 3 were determined to be medium-risk points. (It should be understood that for equipment equipped with GC-MC, when a point is detected and judged to be high-risk, there is no need to continue with the next step of concentration detection. However, in this embodiment, for further verification, a comprehensive test is still performed on the high-risk points.) For non-high-risk points, the risk level is further determined by the signal data nearest neighbor comparison method and the response level classification method.

[0230] Based on the signal response nearest neighbor comparison method, the risk level determination work of 32 unknown points was completed (including the points that have been determined as high risk by the soil gas concentration nearest neighbor comparison method).

[0231] ), according to the data nearest neighbor comparison method, 13 high-risk points (including high-risk points determined by the soil gas concentration nearest neighbor comparison method), 10 low-risk points, and 9 medium-risk points were identified.

[0232] Five points were set up in areas where VOCs detection was not involved or the detection was less than 5 times the detection limit. The PID growth amplitude screening value was determined to be 50%, and the maximum response screening value was 5×104. The FID growth amplitude screening value was 100%, and the maximum response screening value was 1×105. The XSD growth amplitude screening value was 40%, and the maximum response screening value was 2×104. There were 7 points where the maximum growth amplitude or the maximum signal response was less than the screening value. The above points were designated as low-risk points.

[0233] Six points were set up in the area where VOCs exceeded the standard. The VOCs in-situ detection while drilling signal values ​​and soil sample test data were obtained. The FID growth rate screening value was determined to be 900%, and the maximum response screening value was 5×10 5 PID growth rate screening value is 300%, and the maximum response screening value is 1×10 5 The XSD growth rate screening value is 150%, and the maximum response screening value is 6×10 4 There are 13 points (including high-risk points determined by the nearest neighbor comparison method of soil gas concentration) where either the maximum growth rate or the maximum signal response is greater than the screening value.

[0234] The final comprehensive assessment identified 15 high-risk areas, 10 medium-risk areas, and 7 low-risk areas. Laboratory testing and analysis revealed that volatile organic compounds (VOCs) exceeded standards at 9 of the 15 high-risk areas, while no VOCs were found to exceed standards at the low-risk areas.

[0235] While the present invention has been disclosed above with reference to preferred embodiments, this is not intended to limit the present invention. Persons skilled in the art will readily appreciate that various modifications and variations can be made without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention shall be determined by the claims.

Claims

1. A pollution level assessment method based on VOCs in-situ detection while drilling technology, characterized in that: The following steps are involved: Step 1: Based on the land data collection, build a database of potential volatile organic pollutants in the land; Step 2: Based on the historical test results of the plot and the soil pollution occurrence evaluation standards of the site environmental survey, obtain the comprehensive pollution index of soil volatile organic pollutants and the single pollution index of soil pollution, and determine the comprehensive pollution index and single pollution index of each point; Step 3: Obtain signal data obtained by conducting VOCs in-situ while-drilling detection at target points within the plot; Step 4: Based on the detector selected for VOCs in-situ detection while drilling, screen the VOCs in-situ detection while drilling technology measurable factors from the inventory of potential volatile organic pollutants in the plot. Identify the type of volatile organic pollutants by analyzing the different response levels of different detectors and the different responses of different detectors at the same depth; Step 5: Based on the acquired signal data and the types of volatile organic pollutants, the risk level of the survey points is assessed according to whether the VOCs in-situ drilling detection equipment is equipped with GC-MS: For VOCs in-situ drilling detection equipment equipped with GC-MS, soil gas collected at the highest response depth of the detector is qualitatively and quantitatively tested using GC-MS. Based on the obtained soil gas concentration data, the risk level is determined using the nearest neighbor comparison method of soil gas concentration. For VOCs in-situ drilling detection equipment without GC-MS, the risk level of the survey point is determined based on the signal response nearest neighbor comparison method and the response level classification method; Step 6: For any survey point, if it is determined to be at a high risk level based on any one of the soil gas concentration nearest neighbor comparison method, the signal response nearest neighbor comparison method, and the response level classification method, then the survey point is determined to be a high risk point. If any one of the methods determines that the pollution level of the survey point is at a high risk level, then no other method is used to determine the pollution level of the survey point; and If the risk level is determined to be low based on any two or more of the soil gas concentration nearest neighbor comparison method, the signal response nearest neighbor comparison method, and the response level division method, the survey point is determined to be a low-risk point.

2. The pollution level assessment method based on VOCs in-situ detection while drilling technology according to claim 1 is characterized in that: The detectors selected for the VOCs in-situ while drilling detection include PID detectors, FID detectors, ECD detectors and XSD detectors; PID detector, used to detect aromatic hydrocarbons and double-bond chlorine-containing VOCs with ionization energy below 10.6 eV; FID detector, used to detect volatile hydrocarbons (VOCs); ECD detector for detecting polyhalogenated VOCs; XSD detector for the detection of volatile halogenated organic compounds.

3. The pollution level assessment method based on VOCs in-situ detection while drilling technology according to claim 1 is characterized in that: In step 2, the soil volatile organic pollutant comprehensive pollution index P 综 is calculated as follows: In the formula, i represents the type of pollutant, It represents the maximum value of each pollution index in soil volatile organic pollutants. It represents the average value of each pollution index in soil volatile organic pollutants; The soil pollution index P corresponding to each pollutant 单 is calculated as follows: Where C i Indicates the measured value of pollutants, S i is the standard value for pollutant evaluation.

4. The pollution level assessment method based on VOCs in-situ detection while drilling technology according to claim 1 is characterized in that: In step 2, the comprehensive pollution index of each point is calculated as follows: The maximum value of the comprehensive pollution index at each point at different depths represents the comprehensive pollution index of the point, and the result is: Among them, n represents the sampling depth; And the single pollution index of each point is calculated as follows: The maximum value of the single pollution index at different depths for a specific pollutant at each point represents the single pollution index of the factor at that point, and the result is: Among them, n represents the sampling depth and i represents the type of pollutant.

5. The pollution level assessment method based on VOCs in-situ detection while drilling technology according to claim 1 is characterized in that: In step 5, the VOCs in-situ detection while drilling equipment equipped with GC-MS uses GC-MS to perform qualitative and quantitative detection on the soil gas collected at the highest response depth of the detector, and based on the obtained soil gas concentration data, the risk level is determined according to the soil gas concentration nearest neighbor comparison method, including: Obtain soil concentration data and soil gas concentration data at known points, and calculate the concentration of all detected volatile pollutants according to the method in step 3. For unknown points, after obtaining the soil gas concentration data output by GC-MS qualitative and quantitative detection, compare it with the soil gas concentration data of the nearest known point: like Where n1 represents a high risk coefficient, it is determined to be a high risk point; like Where n2 represents the low risk coefficient, it is determined to be a low risk point; Other situations are judged as medium risk points; Furthermore, when new volatile organic pollutants are detected by GC-MS qualitative and quantitative testing at unknown locations, and the concentration of the detected organic pollutants is less than or equal to 3-5 times the detection limit, the newly detected new volatile organic pollutants will be considered as low-risk level factors; When new volatile organic pollutants are detected by GC-MS qualitative and quantitative testing at an unknown point, and the concentration of the detected organic pollutants is greater than 3-5 times the detection limit, and the pollutants detected in the soil of nearby points have not been determined as high-risk points by the nearest neighbor comparison method of soil gas concentration, then the nearest neighbor comparison method of soil gas concentration is determined to be invalid for the new volatile organic pollutants detected by GC-MS qualitative and quantitative testing at the unknown point, and it is necessary to further combine the signal response nearest neighbor comparison method and the response level classification method to determine the risk level of the survey point.

6. The pollution level assessment method based on VOCs in-situ detection while drilling technology according to claim 5 is characterized in that: In step 5, for VOCs in-situ drilling without GC-MS, the risk level of the survey point is determined based on the signal response nearest neighbor comparison method and the response level classification method, including: Acquire signal data from in-situ VOCs detection while drilling without GC-MS. Use the nearest neighbor comparison method to determine the response level of the signal value at the new detection point by comparing it with the nearest neighbor's acquired concentration and signal data points, and determine the risk level. Specifically, (1) Compared with the nearest neighbor point, if the maximum signal value of the new detection point satisfies: Then, it is determined to be a high-risk point; If the maximum signal value of the new detection point satisfies: And the response distance of the increased signal value is greater than 0.1 to 0.2 meters; Then, it is determined to be a high-risk point; Wherein, k1 represents the first risk control threshold, which ranges from 1.2 to 1.5; The signal value increment part refers to the maximum signal value increment being greater than or equal to part; (2) Compared with the nearest neighbor point, if the maximum signal value of the new detection point satisfies: And the response distance of the increased signal value is greater than 0.2 to 0.3 meters; Then, it is determined to be a high-risk point: Wherein, k2 represents the second risk control threshold, which ranges from 0.7 to 0.9; The signal value increment part refers to the maximum signal value increment being greater than or equal to part; (3) Compared with the nearest neighbor point, if the maximum signal value of the new detection point satisfies: Then, it is determined to be a low-risk point; Among them, k3 represents the third risk control threshold, which ranges from 0.2 to 0.4; (4) Other situations are determined to be medium-risk points.

7. The pollution level assessment method based on VOCs in-situ detection while drilling technology according to claim 5 is characterized in that: In step 5, for VOCs in-situ drilling detection equipment without GC-MS, the risk level of the survey point is determined based on the signal response nearest neighbor comparison method and the response level classification method, including: Acquire the signal data obtained from VOCs in-situ drilling without GC-MS, and use the response level classification method to determine the response level of the signal value at the new detection point and determine the risk level. Specifically, The response level is set to 3 levels, including weak response, general response, and strong response; For the detector signal data obtained from new detection points for VOCs in-situ while-drilling detection without GC-MS, the response level and risk level of the new detection points are determined based on the change in each detector signal data compared to the baseline and the maximum response signal value: (1) If the signal data of each detector changes compared to the baseline and the maximum response signal value meets the following conditions, it is determined to be a weak response and a low-risk point: Condition 1: Screening points where volatile organic pollutants are not detected or the detection concentration is less than or equal to 3-5 times the detection limit. The maximum increase in the signal data of each detector compared to the baseline and the maximum response signal value are used as the screening value. The maximum increase in the signal data of each detector and the maximum signal response value at the new detection point are both less than the screening value. (2) If any detector signal data changes compared to the baseline and the maximum response signal value meets the following two conditions, it is determined to be a strong response and a high-risk point: Condition 2: When screening points involving excessive levels of volatile organic pollutants, determine the maximum value of the increase in the value of each detector at each excessive point compared to the baseline and the maximum response signal value. The minimum value of the maximum value of the increase in the value of the maximum signal response among all excessive points is used as the screening value, and either the maximum value of the increase in the value of the signal data of the detector at the newly detected point or the maximum signal response value is greater than the screening value; (3) Other situations are considered to have general responses and are determined to be medium-risk points.

8. The pollution level assessment method based on VOCs in-situ detection while drilling technology according to claim 5 is characterized in that: It further includes the following steps: Based on the pollution level determination results of the survey points, a risk level point map is drawn.

9. A computer system, characterized in that: include: one or more processors; as well as Memory, which stores instructions that can be operated; Wherein, when the instruction is executed by one or more processors, the aforementioned one or more processors perform an operation, and the operation includes the process of executing the pollution level assessment method based on VOCs in-situ drilling detection technology as described in any one of the aforementioned claims 1-8.

10. A computer-readable storage medium for storing one or more programs, wherein the one or more programs include instructions or instruction sets that can be executed by one or more processors, characterized in that: When the instructions or instruction set are executed by one or more processors, the process of the pollution level assessment method based on VOCs in-situ detection while drilling technology described in any one of claims 1 to 8 is performed.

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