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以某油田区地下水为研究对象,对DRASTIC模型的指标进行了继承和改进,评价了研究区地下水的综合防污性能.首先建立了该区潜水综合防污性能评价指标体系,选取了潜水固有防污性能指数、油井分布密度、土地利用类型三个指标.在此基础上,又选取潜水综合防污性能指数、上部隔水层厚度、承压含水层岩性和承压含水层埋深四个指标构建了承压水综合防污性能评价指标体系.采用正方形剖分法划分评价单元,应用AreGlS空间分析模块提取评价指标的性状数据,采用专家打分——层次分析法确定指标权重,选取综合指数模型对地下水综合防污性能进行评价及分区.结果表明:该区大部分地区地下水的综合防污性能较好,主城区及油井分布区的综合防污能力较低.经改进的评价方法能反映出油田区地下水的综合防污性能. 相似文献
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从模型原理、模型计算方法、评价结果三个方面系统地总结了DRASTIC模型的缺陷,并指出国内在地下水防污性能评价上的误区,提出模型的改进方法,在此基础上提出了基于DRASTIC模型的模糊综合评价模型,并应用于九江市的地下水防污性能评价工作,取得了较好的效果。 相似文献
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地下水防污性能评价方法探讨 总被引:52,自引:0,他引:52
地下水防污性能评价是环境规划和决策的有用工具,国外已有许多研究,也提出了各种计算防污性能指数模型。文中着重介绍使用最广泛的DRASTIC模型,并指出其不足之处。根据中国情况,提出用DRTA模型评价潜水的防污性能,用DLCT模型评价承压含水层的防污性能。DRTA模型包含有地下水埋深、包气带评分介质、包气带评分介质的厚度和含水层厚度4 个因子;DLCT模型包含有承压含水层埋深、隔水层岩性、隔水层的连续性和隔水层厚度4个因子。 相似文献
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区域地下水系统防污性能评价方法探讨与验证——以鲁北平原为例 总被引:2,自引:0,他引:2
区域地下水系统防污性能评价,面临影响因子多又复杂、评价指标难以客观性选定和权重不易确定等难题,以至严重影响评价结果的可信性。本文以鲁北平原为例,在以往地下水脆弱性评价常用的DRASTIC模型基础上,采用创新的迭置指数方法,改进为"DRITCS法",选择地下水位埋深、包气带综合岩性、地表2 m内单层厚度大于0.5 m的粘土层厚、含水砂层厚度及其渗透系数、和地下水净补给量等因子,组成区域地下水系统防污性能评价模型。合理地确定了区域地下水系统防污性能评价中关键指标——包气带粘性土层变化影响,并在鲁北平原示范性应用和通过以面源污染为主的三氮污染现状验证的结果表明:本文提出的方法能够客观地反映流域性相变造成的地下水系统防污性能空间差异性和区位分布特征,具有较强的实用性。 相似文献
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地下水防污性能评价是开展地下水保护工作的前提,可以为城镇的规划建设提供参考,具有很强的现实意义。常用的DRASTIC地下水防污性能评价模型简单,易于操作,但该模型是针对所有污染物总体考量,没有考虑到特定污染物在包气带中发生的各种生化作用,只是人为的依据经验值进行评分赋值,具有一定的缺陷性。因此,本次研究针对两种特定污染物氨氮、硝氮,定量了其在包气带中的吸附和生物转化作用,以模型模拟法的LPI模型对北京市昌平区地下水的防污性能进行了评价。评价结果表明,昌平区地下水对于氨氮、硝氮的防污性能具有很好的分带性。从山前到平原,地下水的防污性能逐渐增强。地下水对于氨氮的防污性能好于硝氮。此外,地下水大量开采导致的地下水位下降,也增强了地下水的防污性能。由于地下水的持续开采,2009年地下水对于氨氮、硝氮的防污性能普遍好于2005年。 相似文献
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地下水水源地是当今社会经济发展和生活的主要水源,水源地安全性评价具有十分重要的意义。DRASTIC法是国际上关于水源地脆弱性评价较为成功的一种方法,它较全面地考虑了与水源地脆弱性有关的各种因素,但鉴于水源地水文地质条件复杂程度、研究精度不一,评价结果往往与实际不符,对水源地安全性评价因子的选取和赋予的内涵上应因地而异。该文依托山东省主要城市饮用水安全保证调查评价项目,在DRASTIC法研究的基础上,将评价因子赋予新的内涵,使之更加符合山东省水源地的实际,并对城市地下饮用水水源地安全性作出评价。 相似文献
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Groundwater vulnerability assessment and evaluation of human activity impact (HAI) within the Dead Sea groundwater basin,Jordan 总被引:3,自引:2,他引:1
Groundwater vulnerability to contamination was determined within the Dead Sea groundwater basin, Jordan, using the DRASTIC model and evaluation of human activity impact (HAI). DRASTIC is an index model composed of several hydrogeological parameters and, in this study, the recharge parameter component was calculated as a function of rainfall, soil permeability, slope percentage, fault system, and the intersection locations between the fault system and the drainage system, based on the hydrogeologic characteristics of hard-rock terrain in an arid region. To evaluate the HAI index, a land use/cover map was produced using an ASTER VNIR image, acquired for September 2004, and combined with the resultant DRASTIC model. By comparing the DRASTIC and HAI indices, it is found that human activity is affecting the groundwater quality and increasing its pollution risk. The land use/cover map was verified using the average nitrate concentrations in groundwater associated with land in each class. A sensitivity analysis was carried out in order to study the model sensitivity. The analyses showed that the depth to water table and hydraulic conductivity parameters have no significant impact on the model, whereas the impact of vadose zone, aquifer media, and recharge parameters have a significant impact on the DRASTIC model. 相似文献
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Evaluation of aquifers vulnerability to contamination in the Yarmouk River basin, Jordan, based on DRASTIC method 总被引:2,自引:0,他引:2
The existing different human activities and planned land uses put the groundwater resources in Jordan at considerable risk. There are evidences suggesting that the quality of groundwater supplies in north Jordan is under threat from a wide variety of point and non-point sources including agricultural, domestic, and industrial. Vulnerability maps are designed to show areas of greatest potential for groundwater contamination on the basis of hydrogeological conditions and human impacts. DRASTIC method incorporates the major geological and hydrogeological factors that affect and control groundwater movement: depth to groundwater (D), net recharge (R), lithology of the aquifer (A), soil texture (S), topography (T), lithology of vadose zone (I), and hydraulic conductivity (C). The main goal of this study is to produce vulnerability maps of groundwater resources in the Yarmouk River basin by applying the DRASTIC method to determine areas where groundwater protection or monitoring is critical. ArcGIS 9.2 was used to create the groundwater vulnerability maps by overlaying the available hydrogeological data. The resulting vulnerability maps were then integrated with lineament and land use maps as additional parameters in the DRASTIC model to assess more accurately the potential risk of groundwater to pollution. The general DRASTIC index indicates that the potential for polluting groundwater is low in the whole basin, whereas the resulting pesticide DRASTIC vulnerability map indicates that about 31% of the basin is classified as having moderate vulnerability, which may be attributed to agricultural activities in the area. Although high nitrate concentrations were found in areas of moderate vulnerability, DRASTIC method did not depict accurately the nitrate distribution in the area. 相似文献
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Khaled S. Gemail Mohamed El Alfy Mohamed F. Ghoneim Ahmed M. Shishtawy Moheb Abd El-Bary 《Environmental Earth Sciences》2017,76(9):350
DRASTIC indexing and integrated electrical conductivity (IEC) modeling are approaches for assessing aquifer vulnerability to surface pollution. DRASTIC indexing is more common, but IEC modeling is faster and more cost-effective because it requires less data and fewer processing steps. This study aimed to compare DRASTIC indexing with IEC modeling to determine whether the latter is sufficient on its own. Both approaches are utilized to determine zones vulnerable to groundwater pollution in the Nile Delta. Hence, assessing the nature and degree of risk are important for realizing effective measures toward damage minimization. For DRASTIC indexing, hydrogeological factors such as depth to aquifer, recharge rate, aquifer media, soil permeability, topography, impact of the vadose zone, and hydraulic conductivity were combined in a geographical information system environment for assessing the aquifer vulnerability. For IEC modeling, DC resistivity data were collected from 36 surface sounding points to cover the entire area and used to estimate the IEC index. Additionally, the vulnerable zones identified by both approaches were tested using a local-scale resistivity survey in the form of 1D and 2D resistivity imaging to determine the permeable pathways in the vadose zone. A correlation of 0.82 was obtained between the DRASTIC indexing and IEC modeling results. For additional benefit, the obtained DRASTIC and IEC models were used together to develop a vulnerability map. This map showed a very high vulnerability zone, a high-vulnerability zone, and moderate- and low-vulnerability zones constituting 19.89, 41, 27, and 12%, respectively, of the study area. Identifying where groundwater is more vulnerable to pollution enables more effective protection and management of groundwater resources in vulnerable areas. 相似文献
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Assessment of Groundwater Vulnerability in Upper Betwa River Watershed using GIS based DRASTIC Model
Groundwater, the most vital water resource being used for irrigation, domestic and industrial purposes is nowadays under severe threat of contamination. Groundwater contamination risk assessment is an effective tool for groundwater management. In the study, a DRASTIC model which is based on the seven hydrogeological parameters viz: depth of water, net-recharge, aquifer media, soil media, topography, impact of vadose zone and hydraulic conductivity was used to evaluate the groundwater pollution potentiality of upper Betwa watershed. ArcGIS was used to create the ground water vulnerability map by overlaying the seven layers. Based on groundwater vulnerability map, the watershed has been divided in three vulnerable zones viz; low vulnerability zone with 42.83 km2 of area, moderate with 369.21 km2 area and high having 270.96 km2 of area. Furthermore, the DRASTIC model has been validated by nitrate concentration over the area. Results of validation have shown that in low vulnerable zone, no nitrate contamination has been recorded. While in the moderate zone nitrate has been found in the range of 1.6-10ppm. However, in high vulnerable zone 11-40ppm of nitrate concentration in groundwater has been recorded, which proves that the DRASTIC model is applicable for the prediction of groundwater vulnerability in the watershed and in similar areas too. 相似文献
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Groundwater is a very important natural resource in Khanyounis Governorate (the study area) for water supply and development.
Historically, the exploitation of aquifers in Khanyounis Governorate has been undertaken without proper concern for environmental
impact. In view of the importance of quality groundwater, it might be expected that aquifer protection to prevent groundwater
quality deterioration would have received due attention. In the long term, however, protection of groundwater resources is
of direct practical importance because, once pollution of groundwater has been allowed to occur, the scale and persistence
of such pollution makes restoration technically difficult and costly. In order to maintain basin aquifer as a source of water
for the area, it is necessary to find out, whether certain locations in this groundwater basin are susceptible to receive
and transmit contamination. This study aims to: (1) assess the vulnerability of the aquifer to contamination in Khanyounis
governorate, (2) find out the groundwater vulnerable zones to contamination in the aquifer of the study area, and (3) provide
a spatial analysis of the parameters and conditions under which groundwater may become contaminate. To achieve that, DRASTIC
model within geographic information system (GIS) environment was applied. The model uses seven environmental parameters: depth
of water table, net recharge, aquifer media, soil media, topography, impact of vadose zone, and hydraulic conductivity to
evaluate aquifer vulnerability. Based on this model and by using ArcGIS 9.3 software, an attempt was made to create vulnerability
maps for the study area. According to the DRASTIC model index, the study has shown that in the western part of the study area
the vulnerability to contamination ranges between high and very high due to the relatively shallow water table with moderate
to high recharge potential, and permeable soils. To the east of the previous part and in the south-eastern part, vulnerability
to contamination is moderate. In the central and the eastern part, vulnerability to contamination is low due to depth of water
table. Vulnerability analysis of the DRASTIC Model indicates that the highest risk of contamination of groundwater in the
study area originates from the soil media. The impact of vadose zone, depth to water level, and hydraulic conductivity imply
moderate risks of contamination, while net recharge, aquifer media, and topography impose a low risk of aquifer contamination.
The coefficient of variation indicates that a high contribution to the variation of vulnerability index is made by the topography.
Moderate contribution is made by the depth to water level, and net recharge, while impact of vadose zone, hydraulic conductivity,
soil media, and Aquifer media are the least variable parameters. The low variability of the parameters implies a smaller contribution
to the variation of the vulnerability index across the study area. Moreover, the “effective” weights of the DRASTIC parameters
obtained in this study exhibited some deviation from that of the “theoretical” weights. Soil media and the impact of vadose
zone were the most effective parameters in the vulnerability assessment because their mean “effective” weights were higher
than their respective “theoretical” weights. The depth of water table showed that both “effective” and “theoretical” weights
were equal. The rest of the parameters exhibit lower “effective” weights compared with the “theoretical” weights. This explains
the importance of soil media and vadose layers in the DRASTIC model. Therefore, it is important to get the accurate and detailed
information of these two specific parameters. The GIS technique has provided an efficient environment for analysis and high
capabilities of handling large spatial data. Considering these results, DRASTIC model highlights as a useful tool that can
be used by national authorities and decision makers especially in the agricultural areas applying chemicals and pesticides
which are most likely to contaminate groundwater resources. 相似文献
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Groundwater vulnerability assessment in shallow aquifer of Kathmandu Valley using GIS-based DRASTIC model 总被引:1,自引:0,他引:1
Dhundi Raj Pathak Akira Hiratsuka Isao Awata Luonan Chen 《Environmental Geology》2009,57(7):1569-1578
In this paper, groundwater aquifer vulnerability map has been developed by incorporating the major geological and hydro-geological
factors that affect and control the groundwater contamination using GIS based DRASTIC model. This work demonstrates the potential
of GIS to derive a map by overlying various spatially referenced digital data layers that portrays cumulative aquifer sensitivity
ratings across the Kathmandu Valley, Nepal, providing a relative indication of groundwater vulnerability to contamination.
In fact, the groundwater is the major natural resources in Kathmandu for drinking purpose. The decline in groundwater levels
due to the over exploitation and thus extracted water from shallow aquifer has been contaminated by the infiltration of pollutants
from polluted river and land surface is continuous and serious. As the demand for water for human and industrial use has escalated
and at the same time, the engineering and environmental costs are much higher for new water supplies than maintaining the
existing sources already in use. Management of groundwater source and protecting its quality is therefore essential to increase
efficient use of existing water supplies. Aquifer vulnerability maps developed in this study are valuable tools for environmental
planning and predictive groundwater management. Further, a sensitivity analysis has been performed to evaluate the influence
of single parameters on aquifer vulnerability assessment such that some subjectivity can be reduced to some extent and then
new weights have been computed for each DRASTIC parameters. 相似文献
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This study developed a new paradigm for groundwater vulnerability assessment by modifying the standard DRASTIC index (DI) model based on catastrophe theory. The developed paradigm was called the catastrophe theory-based DI (CDI) model. The proposed model was applied to assess groundwater vulnerability to pollution index (GVPI) in Perak Province, Malaysia. The area vulnerability index was modeled by considering the DRASTIC multiple vulnerability causative factors (VCFs) obtained from different data sources. The weights and ranking of the VCFs were computed by using the inner fuzzy membership mechanism of the CDI model. The estimated vulnerability index values of the CDI model were processed in a geographic information system (GIS) environment to produce a catastrophe theory–DRASTIC groundwater vulnerability to pollution index (CDGVPI) map, which demarcated the area into five vulnerability zones. The produced CDGVPI map was validated by applying the water quality status–vulnerability zone relationship (WVR) approach and the relative operating characteristic (ROC) curve method. The performance of the developed CDI model was compared with that of the standard DI model. The validation results of the WVR approach exhibits 89.29% prediction accuracy for the CDI model compared with 75% for the DI model. Meanwhile, the ROC validation results for the CDI and DI models are 88.8% and 78%, respectively. The GIS-based CDI model demonstrated better performance than the DI model. The GVPI maps produced in this study can be used for precise decision making process in environmental planning and groundwater management. 相似文献
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Aquifer vulnerability assessment using the DRASTIC model at Russeifa landfill,northeast Jordan 总被引:1,自引:0,他引:1
Groundwater is inherently susceptible to contamination from anthropogenic activities and remediation is very difficult and expensive. Prevention of contamination is hence critical in effective groundwater management. In this paper an attempt has been made to assess aquifer vulnerability at the Russeifa solid waste landfill. This disposal site is placed at the most important aquifer in Jordan, which is known as Amman-Wadi Sir (B2/A7). The daily-generated leachate within the landfill is about 160 m3/day and there is no system for collecting and treating this leachate. Therefore, the leachate infiltrates to groundwater and degrades the quality of the groundwater. The area is strongly vulnerable to pollution due to the presence of intensive agricultural activity, the solid waste disposal site and industries. Increasing groundwater demand makes the protection of the aquifer from pollution crucial. Physical and hydrogeological characteristics make the aquifer susceptible to pollution. The vulnerability of groundwater to contamination in the study area was quantified using the DRASTIC model. The DRASTIC model uses the following seven parameters: depth to water, recharge, aquifer media, soil media, topography, impact on vadose zone and hydraulic conductivity. The water level data were measured in the observation wells within the disposal site. The recharge is derived based on precipitation, land use and soil characteristics. The aquifer media was obtained from a geological map of the area. The topography is obtained from the Natural Resources Authority of Jordan, 1:50,000 scale topographic map. The impact on the vadose zone is defined by the soil permeability and depth to water. The hydraulic conductivity was obtained from the field pumping tests. The calculated DRASTIC index number indicates a moderate pollution potential for the study area. 相似文献