Groundwater influence zoning and dynamic evaluation method and device

Abstract

The application discloses a groundwater influence partitioning and dynamic evaluation method and device, comprising the following steps: establishing a baseline database containing background and control benchmarks for groundwater, identifying disturbance sources in the process of mine underground space reuse and constructing a hazard index, analyzing hydrogeological structure and water-conducting channels to establish a conduction connectivity index, constructing water-bearing system vulnerability, receptor sensitivity and prevention and control resilience indexes, calculating groundwater influence field strength index to complete partitioning, obtaining measured values of each evaluation index in the target study area, constructing a double-benchmark deviation index based on background and control benchmarks, quantifying the abnormal degree of the measured values of each evaluation index relative to the benchmark state, determining the influence grade through weight calculation, and dynamically updating the evaluation results with monitoring data. The application can accurately identify abnormal changes in the groundwater environment, improve the objectivity and regional comparability of the evaluation results, effectively reduce the subjectivity caused by artificial partitioning, and continuously correct the evaluation results with changes in engineering operation and monitoring data.

Description

Technical Field

[0001] This invention relates to the field of underground space technology, specifically to a method and apparatus for zoning and dynamic evaluation of groundwater impact. Background Technology

[0002] With the continuous growth in demand for the transformation of resource-depleted mines and the development and utilization of underground space, abandoned mine underground spaces are increasingly being used for underground storage, underground power plants, underground transportation facilities, compressed air energy storage, and underground water storage. Unlike the mining stage, the reuse stage, in addition to inheriting the original geological structure and water diversion channels, introduces new disturbances such as drainage and recharge, fluid or gas injection, ventilation and temperature and humidity changes, and excavation and sealing of structures. These disturbances are transmitted to the groundwater system through faults, fracture zones, old roadways, boreholes, goaf areas, and inter-layer hydraulic connections, which may cause problems such as abnormal fluctuations in groundwater levels, enhanced water chemical disturbances, local pollution migration, and the manifestation of multi-field coupling effects.

[0003] In existing technologies, the evaluation methods for mine groundwater mainly focus on water inrush caused by mining activities, the development of water-conducting fracture zones, and conventional water pollution control. However, the evaluation methods for newly added disturbance sources during the reuse stage are relatively weak. Existing zoning methods usually use fixed buffer distances or empirical thresholds, which fail to fully reflect the control effect of water-conducting channels and spatial heterogeneity, resulting in highly subjective zoning results. Evaluation indicators often use uniform indicators or single water quality indicators, ignoring the differences in the main control mechanisms of different areas and the indirect coupling effects of temperature, gas exchange, etc. Comprehensive judgments are often based on the proportion of abnormal items or the occurrence of single threshold exceedances, which lacks objectivity and comparability.

[0004] Therefore, how to overcome the shortcomings of existing technologies with effective methods has become an urgent technical problem to be solved. Summary of the Invention

[0005] The purpose of this invention is to address the above-mentioned problems by providing a method and apparatus for zoning and dynamic evaluation of groundwater impact.

[0006] The technical solution of this invention is: a method for zoning and dynamic evaluation of groundwater impact, comprising the following steps:

[0007] S1: Establish a baseline database characterizing the original state of groundwater and the synchronous change state of undisturbed areas before the implementation of the underground space reuse project in the mine. The baseline database includes background benchmark data and control benchmark data. S2: Identify disturbance sources in the reuse process of underground space in mines, obtain the spatial location, intensity and characteristics of the disturbance sources, and construct a disturbance source hazard index; S3: Obtain the hydrogeological structure and water diversion channel distribution characteristics of the target study area in the underground space of the mine, and analyze and establish the conduction connectivity index; S4: Combining the structure of the aquifer system, ecological protection goals and engineering control measures, construct the aquifer system vulnerability index, receptor sensitivity index and control resilience index respectively; S5: Divide the target study area of ​​underground space in the mine into several evaluation units. Based on the disturbance source hazard index, conduction connectivity index, water-bearing system vulnerability index, receptor sensitivity index and prevention and control resilience index, calculate the groundwater influence field strength index of each evaluation unit, and divide the groundwater influence zone according to the spatial distribution of the groundwater influence field strength index. S6: Obtain the measured values ​​of each evaluation indicator in the target study area. The evaluation indicators include at least one of water level, water temperature and water chemical characteristics. Construct a dual-benchmark deviation index based on the background benchmark and the control benchmark to quantify the degree of abnormality of the measured values ​​of each evaluation indicator relative to the benchmark state. S7: Determine the weights of the evaluation indicators, convert the dual-benchmark deviation index into a standardized impact value, and calculate the zonal impact score and the total project impact value in combination with the weights of the evaluation indicators to determine the groundwater impact level. When the updated measured values ​​of the evaluation indicators are obtained, recalculate the zonal impact score and the total project impact value to update the groundwater impact level and evaluation results.

[0008] As an improvement to this embodiment of the invention, in step S1, the background reference data is groundwater dynamics, hydrogeological parameters and hydrochemical characteristics data at a continuous hydrological annual scale before the implementation of the reuse project, and the control reference data is monitoring data of areas with weak hydraulic connections within the target study area.

[0009] As an improvement to this embodiment of the invention, in step S2, the disturbance source hazard index is obtained by weighted calculation of the disturbance source intensity, duration of action, operating condition stability and fluid physicochemical differences after dimensionless processing.

[0010] As an improvement to this embodiment of the invention, in step S3, the conductivity index is obtained by weighted calculation of the degree of development of water-conducting structures, the permeability of dominant channels, the hydraulic conduction time and channel connectivity after dimensionless processing.

[0011] As an improvement to this embodiment of the invention, in step S4, the vulnerability index of the aquifer system includes at least the aquifer depth, the thickness of the impermeable layer, the permeability and the groundwater flow velocity; the receptor sensitivity index includes at least the groundwater function level, the distance to the ecologically sensitive target and the protection level; and the prevention and control resilience index includes at least the integrity of the engineering blockade, the monitoring coverage, the early warning response speed and the emergency control capability.

[0012] As an improvement to this embodiment of the invention, in step S5, the groundwater influence zone is divided into a direct disturbance zone, a dominant channel conduction zone, a potential coupling zone, and a stable zone based on the groundwater influence field strength index, and the zone boundary is modified in combination with the distribution characteristics of the dominant water-conducting channels.

[0013] As an improvement of this embodiment of the invention, in step S6, the dual benchmark deviation index is used to reflect the deviation of the evaluation index relative to the background benchmark and the control benchmark.

[0014] As an improvement to this embodiment of the invention, in step S7, the weights of the evaluation indicators are determined by combining the CRITIC weighting method and the entropy weighting method. The total impact value of the project is calculated by the average impact level of the partition, the score of the highest impact partition, and the area ratio of the high impact partition.

[0015] As an improvement of this invention, the evaluation index adopts a hierarchical system that combines general indexes and scenario-triggered indexes, with the scenario-triggered indexes being selectively activated according to the specific application type of underground space reuse.

[0016] To achieve one of the above-mentioned objectives, one embodiment of the present invention provides a groundwater impact zoning and dynamic evaluation device, comprising the following modules: The baseline construction module is used to establish a baseline database characterizing the original state of groundwater and the synchronous change state of undisturbed areas before the implementation of the underground space reuse project in the mine. The baseline database includes background benchmark data and control benchmark data. The disturbance identification module is used to identify disturbance sources in the reuse process of underground space in mines, obtain the spatial location, intensity and characteristics of the disturbance sources, and construct a disturbance source hazard index. The channel analysis module is used to obtain the hydrogeological structure and water diversion channel distribution characteristics of the target study area in the underground space of the mine, and to analyze and establish the conduction connectivity index. The index construction module is used to combine the structure of the aquifer system, ecological protection goals and engineering control measures to construct the aquifer system vulnerability index, receptor sensitivity index and control resilience index, respectively. The zoning module is used to divide the target study area of ​​underground space in the mine into several evaluation units. Based on the disturbance source hazard index, conduction connectivity index, aquifer vulnerability index, receptor sensitivity index and control resilience index, the groundwater influence field strength index of each evaluation unit is calculated, and the groundwater influence zone is divided according to the spatial distribution of the groundwater influence field strength index. The deviation quantification module is used to obtain the measured values ​​of each evaluation indicator in the target study area. The evaluation indicators include at least one of water level, water temperature and water chemical characteristics. A dual-benchmark deviation index is constructed based on the background benchmark and the control benchmark to quantify the degree of abnormality of the measured values ​​of each evaluation indicator relative to the benchmark state. The dynamic evaluation module is used to determine the weights of evaluation indicators, convert the dual-benchmark deviation index into a standardized impact value, and calculate the zonal impact score and the total project impact value in combination with the weights of the evaluation indicators to determine the groundwater impact level. When the updated measured values ​​of the evaluation indicators are obtained, the zonal impact score and the total project impact value are recalculated to update the groundwater impact level and evaluation results.

[0017] The groundwater impact zoning and dynamic evaluation method provided in this invention has the following advantages: This invention can accurately identify abnormal changes in the groundwater environment, improve the objectivity and regional comparability of the evaluation results, and effectively reduce the subjectivity brought about by artificial demarcation. Combined with disturbance source identification and water diversion channel analysis, it can comprehensively reflect the impact path and degree of the reuse of underground space in mines on groundwater, and the evaluation results can be continuously corrected as engineering operation and monitoring data change. Attached Figure Description

[0018] Figure 1 This is a flowchart illustrating the groundwater impact zoning and dynamic evaluation method described in this invention. Figure 2 This is a schematic diagram of the groundwater impact zoning and dynamic evaluation device described in this invention. Detailed Implementation

[0019] The present invention will now be described in detail with reference to the specific embodiments shown in the accompanying drawings. However, these embodiments do not limit the present invention, and any structural, methodological, or functional modifications made by those skilled in the art based on these embodiments are included within the scope of protection of the present invention.

[0020] In this article, the terms "first," "second," etc., are used only to distinguish one element from another, without requiring or implying any actual relationship or order between these elements. In fact, the first element can also be called the second element, and vice versa.

[0021] This invention provides a method for zoning and dynamic evaluation of groundwater impacts, such as... Figure 1 As shown, it includes the following steps: S1: Establish a baseline database characterizing the original state of groundwater and the synchronous changes in undisturbed areas before the implementation of the mine underground space reuse project. The baseline database includes background benchmark data and control benchmark data. Specifically, the background benchmark data consists of groundwater dynamics, hydrogeological parameters, and hydrochemical characteristics data at a continuous hydrological annual scale before the implementation of the reuse project, and the control benchmark data consists of monitoring data of areas with weak hydraulic connections within the target study area.

[0022] In practice, the first step is to collect data on groundwater dynamics, hydrogeological parameters, and hydrochemical characteristics in the affected area and surrounding hydraulically related areas of the mine underground space reuse project. Evaluation indicators include groundwater level, temperature, hydrochemical composition, flow direction, recharge / discharge conditions, and aquifer parameters. The hydrochemical composition includes groundwater pH, conductivity, major ions, total dissolved solids, and redox potential. A baseline database is constructed based on the collected monitoring data. This background benchmark database uses the period before the mine underground space reuse project as the starting point and continuously collects monitoring data for at least one complete hydrological year. Within the study area, hydrogeological analysis and hydraulic connection verification identify areas with weak hydraulic connections to the reused space and unaffected by the project disturbance. Control monitoring points are then established, and monitoring data are acquired using the same evaluation indicators and monitoring frequency as the background benchmark database to characterize the synchronous changes in groundwater in undisturbed areas.

[0023] S2: Identify disturbance sources in the reuse process of underground space in mines, obtain the spatial location, intensity and characteristics of the disturbance sources, and construct a disturbance source hazard index; specifically, the disturbance source hazard index is obtained by weighted calculation of disturbance source intensity, duration of action, working condition stability and fluid physicochemical differences after dimensionless processing.

[0024] In practice, it is necessary to conduct operational condition analysis on the entire process of underground space reuse in mines, identifying the types of disturbance sources generated during the operation and construction phases of the project. These disturbance source types include one or more combinations of drainage and recharge, gas or fluid injection, ventilation and temperature and humidity changes, and excavation and sealing of structures generated during project implementation. The intensity, duration, fluctuation degree of operational conditions, and physicochemical differences of the fluids corresponding to each type of disturbance source must be determined. The disturbance source intensity includes one or more of the following: drainage volume, recharge pressure, injection pressure, injection flow rate, ventilation volume, temperature and humidity change amplitude, excavation volume, and sealing scale. The disturbance source intensity, duration, fluctuation degree of operational conditions, and physicochemical differences of the fluids are dimensionless to eliminate the influence of dimensional differences and numerical magnitudes. Corresponding weights are assigned based on the contribution of each type of disturbance source to the groundwater system. The dimensionless parameters are multiplied by their corresponding weights and then summed to obtain the disturbance source hazard index.

[0025] S3: Obtain the hydrogeological structure and water-conducting channel distribution characteristics of the target study area in the underground space of the mine, analyze and establish the conduction connectivity index; specifically, the conduction connectivity index is obtained by weighted calculation of the degree of development of water-conducting structures, permeability of dominant channels, hydraulic conduction time and channel connectivity after dimensionless processing.

[0026] Here, the hydrogeological structure and water-conducting channel distribution characteristics of the target study area can be obtained by combining one or more methods among hydrogeological drilling, tracer experiments, geophysical exploration, and numerical simulation. These characteristics include water-conducting structural density, equivalent permeability of dominant channels, tracer arrival time, fault-tunnel connectivity, inter-layer hydraulic connection strength, and water-conducting channel continuity. The obtained data are then dimensionless. Corresponding weights are assigned based on the contribution of each data type to groundwater conduction connectivity. The dimensionless data is multiplied by the weights and then summed to obtain the conduction connectivity index.

[0027] S4: Combining the structure of the aquifer system, ecological protection goals, and engineering control measures, construct the aquifer system vulnerability index, receptor sensitivity index, and control resilience index respectively. Specifically, the aquifer system vulnerability index includes at least the aquifer depth, aquitard thickness, permeability, and groundwater flow velocity; the receptor sensitivity index includes at least the groundwater function level, distance to ecologically sensitive targets, and protection level; and the control resilience index includes at least the integrity of engineering sealing, monitoring coverage, early warning response speed, and emergency control capabilities.

[0028] Here, firstly, based on the spatial combination of aquifers and impermeable layers, media permeability, and groundwater dynamic conditions, the aquifer depth, impermeable layer thickness, permeability, and groundwater flow velocity are extracted and weighted after dimensionless processing to obtain the aquifer system vulnerability index. Specifically, the aquifer depth reflects the ease with which the groundwater system is affected by external disturbances; the impermeable layer thickness characterizes the protective capacity of the impermeable barrier; the permeability determines the rate of material and energy exchange between groundwater and the disturbance source; and the groundwater flow velocity reflects the migration and diffusion speed of the disturbance's impact.

[0029] Subsequently, ecological and groundwater protection targets were identified. Based on regional land spatial planning and ecological protection requirements, the groundwater function level, the distance to ecologically sensitive targets, and the protection level were determined. After dimensionless processing, a weighted calculation was performed to obtain the receptor sensitivity index. Specifically, the groundwater function level reflects the service value level of groundwater, such as water supply and ecological maintenance; the distance to ecologically sensitive targets characterizes the spatial proximity of the receptor to the disturbed area; and the protection level reflects the strictness of the receptor's protection under laws, regulations, and planning.

[0030] Based on the design and construction scheme of the underground space reuse project in the mine, the integrity of the engineering sealing, the degree of monitoring coverage, the speed of early warning response, and the emergency control capability are extracted and weighted to obtain the prevention and control resilience index after dimensionless processing. Specifically, the integrity of the engineering sealing reflects the degree of completeness of the water diversion channel blockage and seepage prevention sealing; the degree of monitoring coverage reflects the comprehensiveness of monitoring groundwater dynamics and disturbance changes; the speed of early warning response represents the timeliness of abnormal situation identification and handling; and the emergency control capability characterizes the guarantee level of emergency measures such as interception, drainage, reinjection, and pressure relief in the event of a sudden incident.

[0031] S5: Divide the target study area of ​​underground space in the mine into several evaluation units. Based on the disturbance source hazard index, conduction connectivity index, aquifer vulnerability index, receptor sensitivity index, and prevention and control resilience index, calculate the groundwater influence field strength index for each evaluation unit. Divide the groundwater influence zones according to the spatial distribution of the groundwater influence field strength index. Specifically, the groundwater influence zones are divided into direct disturbance zones, dominant channel conduction zones, potential coupling zones, and stable zones according to the groundwater influence field strength index. The zone boundaries are modified in combination with the distribution characteristics of dominant water-conducting channels.

[0032] In practice, the target study area of ​​the underground space in a mine is divided into several evaluation units using two-dimensional grid units or three-dimensional volumetric units. The disturbance source hazard index, conduction connectivity index, aquifer vulnerability index, receptor sensitivity index, and control resilience index are used as input parameters. The groundwater influence field strength index of each evaluation unit is calculated according to a preset linear weighted formula. Specifically, ,in, Let be the groundwater influence field strength index for the i-th evaluation unit. Let i be the disturbance source hazard index for the i-th evaluation unit. Let be the conduction connectivity index of the i-th evaluation unit. Let i be the vulnerability index of the aquifer system in the i-th evaluation unit. Let i be the receptor sensitivity index of the i-th evaluation unit. Let be the resilience index for the prevention and control of the i-th evaluation unit. , , , , These are the weights corresponding to each index. It can be understood that the prevention and control resilience index is used in the calculation in the form of a negative value to reflect the weakening and offsetting effect of engineering prevention and control measures on groundwater. The other indices are used in the calculation in the form of positive values ​​to jointly reflect the comprehensive impact intensity of the underground space reuse disturbance on each evaluation unit.

[0033] Based on the groundwater influence field strength index of each evaluation unit, a zoning method is used, employing one of the following: quantile threshold method, natural discontinuity method, or cluster analysis, to divide the target study area of ​​the mine's underground space into a direct disturbance zone, a dominant channel conduction zone, a potential coupling zone, and a stable zone. Specifically, the direct disturbance zone is the area with a high groundwater influence field strength index that is adjacent to the main body of the mine's underground space reuse project; the dominant channel conduction zone is the area with a high groundwater influence field strength index that is continuously distributed along dominant water-conducting channels such as faults, fracture zones, old roadways, and boreholes; the potential coupling zone is the area with a medium groundwater influence field strength index that exhibits hysteresis response or multi-field coupling effects; and the stable zone is the area with a low groundwater influence field strength index and where the groundwater state remains stable over a long period. Here, the high, medium, and low values ​​are determined based on the groundwater influence field strength index ranges of all evaluation units within the target study area of ​​the mine's underground space. Subsequently, the zoning boundaries were modified based on the actual distribution characteristics of the advantageous water diversion channels in the target study area of ​​the underground space of the mine, so that the zoning boundaries matched the direction of the water diversion channels, the geological structure boundaries, and the scope of engineering influence.

[0034] S6: Obtain the measured values ​​of each evaluation indicator in the target study area. The evaluation indicators include at least one of water level, water temperature and water chemical characteristics. Construct a dual-benchmark deviation index based on the background benchmark and the control benchmark to quantify the degree of abnormality of the measured values ​​of each evaluation indicator relative to the benchmark state. Specifically, the dual-benchmark deviation index is used to reflect the deviation of the evaluation indicators relative to the background benchmark and the control benchmark.

[0035] Here, the dual-benchmark deviation index , ,in, Let j be the data value of the j-th evaluation indicator in the i-th evaluation unit. Let j be the background benchmark value of the j-th evaluation indicator. Let j be the benchmark value for the j-th evaluation indicator. and These are the standard deviations of the j-th evaluation indicator in the background benchmark and the control benchmark, respectively. This is the weighting factor.

[0036] S7: Determine the weights of the evaluation indicators, convert the dual-benchmark deviation index into standardized impact values, and calculate the zonal impact score and total project impact value based on the evaluation indicator weights to determine the groundwater impact level. When updated measured values ​​of the evaluation indicators are obtained, recalculate the zonal impact score and total project impact value to update the groundwater impact level and evaluation results. Specifically, the CRITIC weighting method and entropy weighting method are combined to determine the weights of the evaluation indicators. The total project impact value is calculated by combining the zonal average impact level, the score of the highest impact zonal, and the area proportion of the high-impact zonal. The evaluation indicators adopt a hierarchical system combining general indicators and scenario-triggered indicators. Scenario-triggered indicators are selectively activated according to the specific application type of underground space reuse. For example, when the reuse scenario is compressed air energy storage or underground gas storage, gas leakage flux, dissolved oxygen mutation, carbon dioxide partial pressure change, and temperature and pressure cycle amplitude are added; when the reuse scenario is underground water storage or recharge project, water level rise and fall rate, water chemical mixing index, and exchange cycle are added; when the reuse scenario is underground plant or transportation facility, drainage load, concrete leachate index, and probability of release from local pollution sources are added.

[0037] Here, the specific method for determining the weights of evaluation indicators by combining the CRITIC weighting method and the entropy weighting method is as follows: , ,in, Let j be the weight of the j-th evaluation indicator. This is the weighting coordination coefficient. The partitioning affects the score. ,in, The partition impact score for the i-th evaluation unit. This refers to the piecewise membership function or logical function corresponding to the dual-benchmark deviation index. The total impact value of the project... , ,in, The average score is affected by partitioning all evaluation units. The highest value affecting the score across all evaluation units. The evaluation index is defined as the proportion of high-impact zone area. The hierarchical system of the evaluation indicators specifically includes: the general indicators are applicable to various mining underground space reuse scenarios, and the scenario trigger indicators are invoked based on operating conditions such as gas storage, water storage, plant, transportation, or energy storage. This approach aims to make the evaluation system more universal.

[0038] Example This embodiment uses the conversion of an abandoned coal mine's underground space into a compressed air energy storage (CAES) plant as an application scenario. The coal seam is buried at a depth of 300-500m, and the target layer mainly consists of a sandstone aquifer and a mudstone impermeable layer. The sandstone aquifer has a permeability coefficient of 1.2 × 10⁻⁶. -4 cm / s, the permeability coefficient of the mudstone aquitard is 5×10-7 cm / s, the effective volume of the underground plant is 100,000 m³. 3 The design operating pressure is 0.7-0.9 MPa. An evaluation area is set out within 300 m of the plant, divided into 12 two-dimensional evaluation units of 50m×50m, numbered U1-U12. One main fault F1, two abandoned old tunnels, and four historical boreholes were identified in the study area. Fault F1 strikes NE35°, dips SE, and has a dip angle of 63°, with a fracture zone width of 1.2-2.8m.

[0039] The steps for implementing the groundwater impact zoning and evaluation method described in this invention are as follows: Step S1: Prior to implementation, groundwater background data for 12 consecutive months was acquired. Control monitoring points were established in the area with weak hydraulic connectivity on the north side of the study area to create a background baseline database and a control baseline database. Selected evaluation indicators included water level fluctuation amplitude, electrical conductivity, and... Concentration, dissolved oxygen abrupt change, temperature cycle amplitude, CO2 partial pressure change, and gas leakage flux. Reference values ​​for each indicator are shown in Table 1.

[0040] Table 1. Main parameters of the background benchmark database and the control benchmark database.

[0041] Step S2: This embodiment identifies four types of disturbance sources: compressed air injection disturbance, ventilation and temperature / humidity change disturbance, drainage and recharge disturbance, and sealing and grouting construction disturbance. The design pressure for compressed air injection is 0.82 MPa, and the injection flow rate is 5.4 × 10⁻⁶. 4 m 3 / h, single session lasting 8 hours; ventilation volume is 1.8×10 5 m 3 / h, the temperature fluctuation range inside the plant is 10.8-12.4℃; the drainage volume is 240-320 m³ / h. 3 / d, reinjection pressure is 0.18MPa; the sealing section length is 210m, and the grouting volume is 860m³. 3 After dimensionlessizing the disturbance parameters, the disturbance source hazard index is calculated with weights of 0.40, 0.20, 0.25, and 0.15, respectively. Taking the first evaluation unit U1 as an example, the dimensionless values ​​of its corresponding gas injection disturbance, ventilation disturbance, drainage and return water disturbance, and sealing construction disturbance are 0.98, 0.86, 0.91, and 0.88, respectively. Therefore: H1 = 0.40 × 0.98 + 0.20 × 0.86 + 0.25 × 0.91 + 0.15 × 0.88 = 0.9235. Thus, the disturbance source hazard index H1 of the first evaluation unit U1 is 0.9235.

[0042] Step S3: A comprehensive approach combining hydrogeological drilling, transient electromagnetic detection, NaBr tracer tests, and numerical simulations was used to identify water-conducting channels. In the tracer test, 20 kg of NaBr solution was injected into borehole K2. Monitoring results showed that the tracer arrival times for the areas of the third evaluation unit U3 and the fourth evaluation unit U4 were 26 h and 31 h, respectively, for the sixth evaluation unit U6 it was 44 h, while the tenth evaluation unit U10 showed no significant response within 96 h, indicating a clearly dominant conduction channel at the intersection of fault F1 and the old tunnel. Further inversion yielded an equivalent permeability of 2.7 × 10⁻⁶ for the channel area. -5 m / s, with a stable region of only 3.5 × 10 m / s. -7 m / s. In this embodiment, the density of water-conducting structures, the equivalent permeability of dominant channels, the tracer arrival time, and the fault and tunnel connectivity are dimensionless, and the conduction connectivity index is calculated by weighting at 0.30, 0.35, 0.20, and 0.15. Taking the third evaluation unit U3 as an example, its corresponding four dimensionless values ​​are 0.92, 0.95, 0.88, and 0.83, respectively. Therefore: C3 = 0.30 × 0.92 + 0.35 × 0.95 + 0.20 × 0.88 + 0.15 × 0.83 = 0.909. Thus, the conduction connectivity index C3 of the third evaluation unit U3 is 0.909.

[0043] Step S4: In this embodiment, the spacing between monitoring holes is controlled at 80-120 m, the early warning response time is controlled within 2 hours, and the emergency interception capacity is 420 m³. 3 / d.

[0044] Step S5: In this embodiment, the following is taken: =0.30, =0.25, =0.20, =0.15, =0.10, according to the formula: The various indices, groundwater influence field strength index, and zoning of each evaluation unit were calculated, and the results are shown in Table 2.

[0045] Table 2 Calculation results and zoning results for each evaluation unit index

[0046] This embodiment uses a method combining natural discontinuity and water channel boundary correction to divide the target study area of ​​the underground space of the mine into four types of regions: when G i The direct disturbance region is defined as 0.66; when it reaches 0.52... G i When <0.66, it is the dominant channel conduction zone; when 0.30 G iWhen G < 0.52, it is a potential coupling region; when G i The stability zone is defined as 0.30. According to the results in Table 2, the first evaluation unit U1 and the second evaluation unit U2 are adjacent to the main plant and have a high disturbance source hazard index, and are therefore classified as direct disturbance zones. The third evaluation unit U3 and the fourth evaluation unit U4 are distributed along fault F1 and the old tunnel, and have a significantly high conduction connectivity index, and are therefore classified as dominant channel conduction zones. Although the fifth evaluation unit U5 to the ninth evaluation unit U9 are not directly adjacent to the plant, the groundwater influence field strength index is moderate under the combined effects of interlayer hydraulic connection and circulation conditions, and are therefore classified as potential coupling zones. The tenth evaluation unit U10 to the twelfth evaluation unit U12 are far from the disturbance source and are jointly controlled by the impermeable layer and the sealing system, and are therefore classified as stable zones.

[0047] Step S6: Select one representative monitoring point P1-P4 in each of the four types of zones for dynamic monitoring. The monitoring results are shown in Table 3.

[0048] Table 3. Monitoring values ​​of representative monitoring points in each zone

[0049] Based on the dual-benchmark deviation index formula, the tradeoff coefficient is taken. Calculate the deviation of each evaluation index. Taking the water level fluctuation amplitude at point P1, a representative point in the direct disturbance zone, as an example, substitute X=0.62, B=0.18, C=0.15, σ B =0.05、σ C =0.04, the index deviation is 9.98, and the index deviation of the same index in the stable region P4 is 0.74, indicating that the direct disturbance region has deviated significantly from the background and control state.

[0050] Step S7: The weights of the evaluation indicators are determined by combining the CRITIC weighting method and the entropy weighting method. The weight coordination coefficient μ = 0.5 is taken. The weight results of each evaluation indicator are shown in Table 4.

[0051] Table 4 Calculation Results of Indicator Combination Weights

[0052] This embodiment uses logical functions: The deviation index is converted into a standardized impact value, and the impact score S for each sub-region is calculated. i The results are shown in Table 5.

[0053] Table 5 Impact Score for Each Zone and Overall Judgment Results

[0054] From Table 5, the area-weighted average influence level of each zone is: =0.975×0.167+0.912×0.167+0.587×0.417+0.147×0.250=0.597. The highest score for the high-impact zone is the score of the direct disturbance zone, which is 0.975. The area ratio of the high-impact zone is the sum of the areas of the direct disturbance zone and the dominant channel transmission zone, which is 0.334. Taking a=0.4, b=0.4, and c=0.2, the total impact value R of the project is: R=0.4×0.597+0.4×0.975+0.2×0.334=0.6956.

[0055] This embodiment classifies the impact level as follows: low impact R < 0.25; lower impact 0.25. R < 0.50; Higher impact: 0.50 R<0.75; High impact: R 0.75. Therefore, the overall groundwater impact level of this project is determined to be high in this embodiment. The directly disturbed area and the dominant transmission channel area should be designated as key control areas, with priority given to measures such as secondary grouting and sealing, enhanced monitoring, and stable flow drainage and regulation.

[0056] Secondary grouting was carried out at the intersection of fault F1 and the old roadway. After adjusting the drainage and return water operation from intermittent fluctuations to steady flow for three months, monitoring showed a significant decrease in gas leakage flux and temperature cycle amplitude in both the direct disturbance zone and the dominant channel conduction zone. Recalculations showed that S1 in the direct disturbance zone decreased from 0.975 to 0.780, S2 in the dominant channel conduction zone decreased from 0.912 to 0.653, and the total impact value R decreased from 0.6956 to 0.587. Although the impact level is still relatively high, it is close to the low impact threshold. This indicates that the method described in this invention can be dynamically updated according to changes in monitoring data and control measures, and is applicable to the identification and zoning control of groundwater impacts throughout the entire process of mine underground space reuse.

[0057] This invention also provides a groundwater impact zoning and dynamic evaluation device, such as... Figure 2 As shown, it includes the following modules: The baseline construction module 201 is used to establish a baseline database characterizing the original state of groundwater and the synchronous change state of undisturbed areas before the implementation of the underground space reuse project in the mine. The baseline database includes background benchmark data and control benchmark data. The disturbance identification module 202 is used to identify disturbance sources in the process of reusing underground space in mines, obtain the spatial location, intensity and characteristics of the disturbance sources, and construct a disturbance source hazard index. The channel analysis module 203 is used to obtain the hydrogeological structure and water diversion channel distribution characteristics of the target study area in the underground space of the mine, and to analyze and establish the conduction connectivity index. The index construction module 204 is used to construct the water-aquifer vulnerability index, receptor sensitivity index, and control resilience index by combining the structure of the water-aquifer system, ecological protection goals, and engineering control measures. The partitioning module 205 is used to divide the target study area of ​​underground space in the mine into several evaluation units. Based on the disturbance source hazard index, conduction connectivity index, water-bearing system vulnerability index, receptor sensitivity index and prevention and control resilience index, the groundwater influence field strength index of each evaluation unit is calculated respectively, and the groundwater influence partition is divided according to the spatial distribution of the groundwater influence field strength index. The deviation quantification module 206 is used to obtain the measured values ​​of each evaluation index in the target study area. The evaluation index includes at least one of water level, water temperature and water chemical characteristics. A dual-benchmark deviation index is constructed based on the background benchmark and the control benchmark to quantify the degree of abnormality of the measured values ​​of each evaluation index relative to the benchmark state. The dynamic evaluation module 207 is used to determine the weights of the evaluation indicators, convert the dual-benchmark deviation index into a standardized impact value, and calculate the zonal impact score and the total project impact value in combination with the weights of the evaluation indicators to determine the groundwater impact level. When the updated measured values ​​of the evaluation indicators are obtained, the zonal impact score and the total project impact value are recalculated to update the groundwater impact level and evaluation results.

[0058] This invention can be an apparatus, method, and / or computer program product. A computer program product may include a readable storage medium having computer-readable program instructions loaded thereon for causing a processor to implement various aspects of the invention.

[0059] Storage media can be tangible devices that hold and store instructions for use by instruction execution devices. Storage media can include, but are not limited to, electrical storage devices, magnetic storage devices, optical storage devices, electromagnetic storage devices, semiconductor storage devices, or any suitable combination thereof. More specific examples (a non-exhaustive list) of readable storage media include: portable computer disks, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), static random access memory (SRAM), portable compact disc read-only memory (CD-ROM), digital multifunction disc (DVD), memory sticks, floppy disks, mechanical encoding devices, such as punch cards or recessed protrusions storing instructions thereon, and any suitable combination thereof.

[0060] It should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This way of describing the specification is only for clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

[0061] The detailed descriptions listed above are merely specific descriptions of feasible embodiments of the present invention, and are not intended to limit the scope of protection of the present invention. All equivalent embodiments or modifications made without departing from the spirit of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for zoning and dynamic evaluation of groundwater impacts, characterized in that, Includes the following steps: S1: Establish a baseline database characterizing the original state of groundwater and the synchronous change state of undisturbed areas before the implementation of the underground space reuse project in the mine. The baseline database includes background benchmark data and control benchmark data. The background benchmark data are groundwater dynamics, hydrogeological parameters and hydrochemical characteristics data at a continuous hydrological annual scale before the implementation of the reuse project. The control benchmark data are monitoring data of areas with weak hydraulic connection in the target study area. S2: Identify disturbance sources in the reuse process of underground space in mines, obtain the spatial location, intensity and characteristics of the disturbance sources, and construct a disturbance source hazard index; S3: Obtain the hydrogeological structure and water diversion channel distribution characteristics of the target study area in the underground space of the mine, and analyze and establish the conduction connectivity index; S4: Combining the structure of the aquifer system, ecological protection goals, and engineering control measures, construct the aquifer system vulnerability index, receptor sensitivity index, and control resilience index respectively. The aquifer system vulnerability index includes at least the aquifer depth, aquitard thickness, permeability, and groundwater flow velocity. The receptor sensitivity index includes at least the groundwater function level, distance to ecologically sensitive targets, and protection level. The control resilience index includes at least the integrity of engineering sealing, monitoring coverage, early warning response speed, and emergency control capability. S5: Divide the target study area of ​​underground space in the mine into several evaluation units. Based on the disturbance source hazard index, conduction connectivity index, water-bearing system vulnerability index, receptor sensitivity index and prevention and control resilience index, calculate the groundwater influence field strength index of each evaluation unit, and divide the groundwater influence zone according to the spatial distribution of the groundwater influence field strength index. S6: Obtain the measured values ​​of each evaluation indicator in the target study area. The evaluation indicators include at least one of water level, water temperature and water chemical characteristics. Construct a dual-benchmark deviation index based on the background benchmark and the control benchmark to quantify the degree of abnormality of the measured values ​​of each evaluation indicator relative to the benchmark state. S7: Determine the weights of the evaluation indicators, convert the dual-benchmark deviation index into a standardized impact value, and calculate the zonal impact score and the total project impact value in combination with the weights of the evaluation indicators to determine the groundwater impact level. When the updated measured values ​​of the evaluation indicators are obtained, recalculate the zonal impact score and the total project impact value to update the groundwater impact level and evaluation results.

2. The method for zoning and dynamic evaluation of groundwater impact according to claim 1, characterized in that, In step S2, the disturbance source hazard index is obtained by weighted calculation of the disturbance source intensity, duration of action, operating condition stability and fluid physicochemical differences after dimensionless processing.

3. The method for zoning and dynamic evaluation of groundwater impact according to claim 1, characterized in that, In step S3, the conductivity index is obtained by weighted calculation of the degree of development of water-conducting structures, the permeability of dominant channels, the hydraulic conduction time and channel connectivity after dimensionless processing.

4. The method for zoning and dynamic evaluation of groundwater impact according to claim 1, characterized in that, In step S5, the groundwater impact zone is divided into a direct disturbance zone, a dominant channel conduction zone, a potential coupling zone, and a stable zone based on the groundwater impact field strength index. The zone boundaries are modified in combination with the distribution characteristics of the dominant water-conducting channels.

5. The method for zoning and dynamic evaluation of groundwater impact according to claim 1, characterized in that, In step S6, the dual-benchmark deviation index is used to reflect the deviation of the evaluation index relative to the background benchmark and the control benchmark.

6. The method for zoning and dynamic evaluation of groundwater impact according to claim 1, characterized in that, In step S7, the weights of the evaluation indicators are determined by combining the CRITIC weighting method and the entropy weighting method. The total impact value of the project is calculated by the average impact level of the partition, the score of the partition with the highest impact, and the area ratio of the partition with high impact.

7. The method for zoning and dynamic evaluation of groundwater impact according to claim 1, characterized in that, The evaluation indicators adopt a hierarchical system that combines general indicators with scenario-triggered indicators. The scenario-triggered indicators are selectively activated according to the specific application type of underground space reuse.

8. A groundwater impact zoning and dynamic evaluation device, characterized in that, Includes the following modules: The baseline construction module is used to establish a baseline database characterizing the original state of groundwater and the synchronous change state of undisturbed areas before the implementation of the underground space reuse project in the mine. The baseline database includes background benchmark data and control benchmark data. The background benchmark data are groundwater dynamics, hydrogeological parameters and hydrochemical characteristics data at a continuous hydrological annual scale before the implementation of the reuse project. The control benchmark data are monitoring data of areas with weak hydraulic connections in the target study area. The disturbance identification module is used to identify disturbance sources in the reuse process of underground space in mines, obtain the spatial location, intensity and characteristics of the disturbance sources, and construct a disturbance source hazard index. The channel analysis module is used to obtain the hydrogeological structure and water channel distribution characteristics of the target study area in the underground space of the mine, and to analyze and establish the conduction connectivity index. The index construction module is used to combine the structure of the aquifer system, ecological protection goals and engineering control measures to construct the aquifer system vulnerability index, receptor sensitivity index and control resilience index, respectively. The zoning module is used to divide the target research area of ​​underground space in the mine into several evaluation units. Based on the disturbance source hazard index, conduction connectivity index, aquifer vulnerability index, receptor sensitivity index, and prevention and control resilience index, the groundwater influence field strength index of each evaluation unit is calculated. The groundwater influence zone is divided according to the spatial distribution of the groundwater influence field strength index. The aquifer vulnerability index includes at least the aquifer depth, aquitard thickness, permeability, and groundwater flow velocity. The receptor sensitivity index includes at least the groundwater function level, distance to ecologically sensitive targets, and protection level. The prevention and control resilience index includes at least the integrity of engineering sealing, monitoring coverage, early warning response speed, and emergency control capability. The deviation quantification module is used to obtain the measured values ​​of each evaluation indicator in the target study area. The evaluation indicators include at least one of water level, water temperature and water chemical characteristics. A dual-benchmark deviation index is constructed based on the background benchmark and the control benchmark to quantify the degree of abnormality of the measured values ​​of each evaluation indicator relative to the benchmark state. The dynamic evaluation module is used to determine the weights of evaluation indicators, convert the dual-benchmark deviation index into a standardized impact value, and calculate the zonal impact score and the total project impact value in combination with the weights of the evaluation indicators to determine the groundwater impact level. When the updated measured values ​​of the evaluation indicators are obtained, the zonal impact score and the total project impact value are recalculated to update the groundwater impact level and evaluation results.

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