石油类污染场地土壤与地下水污染调查实例分析

以冀中平原某石油类污染场地为例,从污染源分布勘察、场地水文地质模型建立、土壤及地下水的现场调查入手,采用物探、坑探、钻探综合调查技术和定深取样等一些取样方法,对不同深度土壤及地下水的有机污染进行调查和样品分析。结果表明:整个场地的土壤和地下水受到不同程度的污染,30m深度内包气带和饱水带已被污染,50m深度的地下水中有有机污染物检出,石油类场地的污染特征主要表现为土壤及其地下水中含有高浓度单环芳烃和卤代烃。且单环芳烃在土壤与地下水中的浓度高于其它有机污染物。     

北京某垃圾处置场对地下水的污染

通过对北京某垃圾场所处的环境地质条件、地层对垃圾污染物的防护能力的调查及对地下水连续1个水文年的污染监测,用单因子和多因子(综合污染指数和内梅罗污染指数)2种方法,评价了该垃圾场对地下水的污染情况。结果表明,该垃圾场对地下水的污染极其严重：综合污染指数可达到59;单项污染组分如NO2^-、NH4^ 、COD等普遍比参照值高出几十倍,致癌物质NO2^-则高出340多倍。从水质的角度看,地下水中有的污染物(NO2^-、NH4^ 、COD)已经超出地下水Ⅲ类水质标准数十倍甚至100多倍,到了不能饮用的程度。这表明地质环境对地下水资源的防护能力直接关系到国土资源的合理利用及城市管理,若垃圾处置场选址不当,将污染地下水资源,影响城市可持续发展。     

Application of multiple-point geostatistics on modelling groundwater flow and transport in a cross-bedded aquifer (Belgium)

Sedimentological processes often result in complex three-dimensional subsurface heterogeneity of hydrogeological parameter values. Variogram-based stochastic approaches are often not able to describe heterogeneity in such complex geological environments. This work shows how multiple-point geostatistics can be applied in a realistic hydrogeological application to determine the impact of complex geological heterogeneity on groundwater flow and transport. The approach is applied to a real aquifer in Belgium that exhibits a complex sedimentary heterogeneity and anisotropy. A training image is constructed based on geological and hydrogeological field data. Multiple-point statistics are borrowed from this training image to simulate hydrofacies occurrence, while intrafacies permeability variability is simulated using conventional variogram-based geostatistical methods. The simulated hydraulic conductivity realizations are used as input to a groundwater flow and transport model to investigate the effect of small-scale sedimentary heterogeneity on contaminant plume migration. Results show that small-scale sedimentary heterogeneity has a significant effect on contaminant transport in the studied aquifer. The uncertainty on the spatial facies distribution and intrafacies hydraulic conductivity distribution results in a significant uncertainty on the calculated concentration distribution. Comparison with standard variogram-based techniques shows that multiple-point geostatistics allow better reproduction of irregularly shaped low-permeability clay drapes that influence solute transport.     

石家庄市地下水污染特征及其与超量开采的关系

石家庄市地下水污染以常量组分的含量和指标升高为主要特征，污染源主要来自城市污水，这在我国城市地区地下水污染问题中极具代表性。本在分析污染特征的基础上，对地下水污染与超量开采的关系进行了研究和探讨，揭示了超量开采加剧地下水污染进程的机理，进而提出，超量开采地下水是导致地下水污染的重要诱导因素。     

某化工场地土壤与地下水中多环芳烃的分布特征及迁移规律

选取某化工场地作为研究对象,采集不同深度的原状土壤样品和原状地下水样品,对土壤样品和地下水样品的16种优控多环芳烃进行定量分析,研究不同种类的多环芳烃在包气带和饱和带中的分布特征和迁移规律.研究表明,在平面上,多环芳烃在土壤和地下水中的污染高值区与生产车间分布基本一致;在垂向上,土壤中的16种多环芳烃集中分布在杂填土层...     

张集地区地下水易污性及污染风险评价

文章在地下水易污性和污染风险评价方法的基础上,根据张集地区的水文地质状况和土地利用情况,建立了地区地下水易污性和污染风险评价的指标方法:GRADIC法和GRADICL法,并利用GIS/Arcinfo软件对地区地下水易污性和污染风险进行评价,得到张集地区地下水易污性指数和污染风险指数及其分布图。评价结果对于张集地区地下水合理开发利用、科学管理和有效保护,实现地区地下水资源的可持续利用具有实际意义。     

Limitations in the use of compound-specific stable isotope analysis to understand the behaviour of a complex BTEX groundwater contamination near Brussels (Belgium)

The application of compound-specific stable isotope analysis (CSIA) was evaluated to characterise a complex groundwater contamination. For this purpose, δ¹³C and δ²H analysis of benzenes and alkylated derivatives were used to interpret both the impact of different sources on a contaminant plume and the presence of degradation processes. The different contaminant sources could be distinguished based on their combined δ¹³C–δ²H signature of the benzene, toluene, ethylbenzene and xylenes (BTEX) dissolved in the groundwater. Despite this source differentiation, plume characterisation was not possible due to the complex mixing of the respective contaminant plumes. Furthermore, the original isotope signatures of the sources were not preserved across these plumes. To estimate the level of in situ biodegradation independently from concentration data, the Rayleigh equation was used. Although current literature identifies the application of CSIA as very promising in the frame of characterising organic groundwater pollution, this study has indicated that this approach can be limited with respect to successfully distinguish the different plumes and their relation to the known source zones.     

Degradation of carbon disulphide (CS2) in soils and groundwater from a CS2-contaminated site

This study is the first investigation of biodegradation of carbon disulphide (CS₂) in soil that provides estimates of degradation rates and identifies intermediate degradation products and carbon isotope signatures of degradation. Microcosm studies were undertaken under anaerobic conditions using soil and groundwater recovered from CS₂-contaminated sites. Proposed degradation mechanisms were validated using equilibrium speciation modelling of concentrations and carbon isotope ratios. A first-order degradation rate constant of 1.25 × 10^?2 h^?1 was obtained for biological degradation with soil. Carbonyl sulphide (COS) and hydrogen sulphide (H₂S) were found to be intermediates of degradation, but did not accumulate in vials. A ¹³C/¹²C enrichment factor of ?7.5 ± 0.8 ‰ was obtained for degradation within microcosms with both soil and groundwater whereas a ¹³C/¹²C enrichment factor of ?23.0 ± 2.1 ‰ was obtained for degradation with site groundwater alone. It can be concluded that biological degradation of both CS₂-contaminated soil and groundwater is likely to occur in the field suggesting that natural attenuation may be an appropriate remedial tool at some sites. The presence of biodegradation by-products including COS and H₂S indicates that biodegradation of CS₂ is occurring and stable carbon isotopes are a promising tool to quantify CS₂ degradation.     

Geochemical and mineralogical study of a site severely polluted with heavy metals (Maatheide, Lommel, Belgium)

The former zinc smelter site ‘de Maatheide’ in Lommel (Belgium) was severely polluted with heavy metals and the pollution spread into the surroundings by rain water leaching and wind transportation. This study focuses on the processes of immobilization and natural attenuation that took place on the site. Three important factors were found. Firstly, the high pH values (pH 7–8) in the topsoil influence the mobility of heavy metals. Secondly, the spodic horizons below the polluted top layer seem to accumulate heavy metals, thereby slowing down their release into the environment. Finally, the glassy phases and iron oxi/hydroxides that are present can encapsulate heavy metals during their formation/recrystallization, thereby immobilizing them. An additional shielding effect results from the reaction rims of goethite around the contaminant phases, which partially inhibit the weathering process and release of contaminants. This shielding effect is an important factor to take into account when modelling contaminant release.     

Guidelines to locate and protect high-quality groundwater in Baiyu Mountain area of China

The Baiyu Mountain area has the most shortage of water in the Ordos Basin of China. The majority of the groundwater is in the Luohe water-bearing formation, which is characterized by high total dissolved solids (TDS). The concentration of TDS can be as high as 10.45 g/l, which makes the water unsuitable for either potable or irrigation purpose. The dominant ions in the groundwater are SO^2–₄·Cl^–. The maximum concentrations of SO^2–₄ and Cl^– are 3,170 and 3,830 mg/l, respectively. The areas with low TDS groundwater are in Jingbian and Zhidan counties. However, nitrogen pollution caused by human and agriculture activities is a significant threat to the protection of fresh water in these counties.     

Geochemistry of overbank and high-order stream sediments in Belgium and Luxembourg: a way to assess environmental pollution

A geochemical survey of Belgium and Luxembourg was carried out as part of an international research project entitled ‘Regional geochemical mapping of Western Europe towards the year 2000'. The aim of this research was to map regional background geochemical patterns based on pristine or at least pre-industrial overbank samples and to deduce regional information on the degree of environmental pollution of floodplain and present-day river sediments. Over the entire study area (about 33,000 km²), 66 overbank sites have been sampled. Catchment areas range between 60 and 600 km². At each site an overbank profile has been dug out in the immediate vicinity of the river and described in detail. A first composite sample was taken 5–25 cm below the surface. This sample is supposed to represent deposition over the last centuries. Human interferences in this interval are often inferable based on changed sedimentary characteristics and the presence of anthropogenic particles such as charcoal, slags and brick fragments. A second composite sample was taken at depth, usually >1.5 m below the surface over an interval of about 20 cm. In most sites, the profile characteristics allowed to assume pre-industrial or even pristine conditions for this lower overbank sample. In some profiles this was confirmed by ¹⁴C-dating and/or by the absence of anthropogenic particles. Finally, a present-day stream sediment was sampled on the site to infer the actual pollution status. After drying at 80°C, disaggregation and sieving, the <125 μm fractions of the three sediment samples were analysed by XRF for major elements and several trace elements. Lower overbank samples generally show a direct link with the geological substrate and allow to assess natural background concentrations. Results from the mapping exercise as well as from the statistical analyses display a clear contrast between the northern part of Belgium where Cenozoic unconsolidated sandy and silty formations dominate which are especially vulnerable for erosion, and the southern part of Belgium and Luxembourg where Paleozoic and Mesozoic sandstones, carbonates, marls and shales are the prevalent lithologies. Here the shales are the most intensively eroded lithologies. This is especially reflected in the element patterns of Al₂O₃, MgO, K₂O, Ga, Ni, Rb, Sc and V which negatively correlate with SiO₂. Despite the human related pollution, the geological contrast between north and south Belgium is still recognisable in the geochemical pattern of the upper overbank and present-day stream sediment samples for the above-mentioned elements. Furthermore there is a clear increase in heavy metal contents (Zn, Cd, Pb, Cu), As and in certain locations in Ba from the lower to the upper overbank sediment, as well as to the present-day stream sediment. The relative increase in element content allows to assess the degree of pollution and helps to define those drainage areas where more detailed research is needed.     

Characterization of groundwater flow in the Bailin hazardous waste-disposal site (Huesca, Spain)

 A serious problem in Spain is presented, where the water and soil were contaminated by lindane produced by the chemical industry, at a time when environmental legislation was limited, and the hydrogeological characterization of the low permeability materials was insufficient. The waste-disposal sites where the lindane accumulated lacked suitable sealing and also had notable filtration. The non-existence of a safe waste-disposal site, and the economic and social problems of transporting lindane residues forced the alternative proposal of confining these residues in situ (Government of Aragón, 1995, 1996). Once the surface sealing was carried out, the problem centred on the site's underground confinement. The purpose of this publication is to present the particular hydrogeological behaviour of materials, which were initially considered impermeable because of the presence of very consolidated sandstone beddings and the vertical disposition of the strata, and so allowed the lindane to escape through the groundwater. In addition, this publication describes the procedures carried out in order to achieve effective underground confinement at the waste-disposal site. Received: 12 October 1999 · Accepted: 31 January 2000     

淮河流域（山东段）南部平原区浅层地下水有机污染特征

随着经济的发展,淮河流域山东段南部平原区地下水污染、环境问题日趋严重。就该区浅层地下水有机污染特征进行了总结,并就污染源、浅层地下水及表层土壤有机污染现状、河流对两侧浅层地下水的影响及污染途径等问题进行了研究。结果表明,该地区浅层地下水中有机组分检出率较低,有机组分中仅有个别指标水质超标,研究区浅层地下水有机污染程度整体较轻。平面分布特征上,有机物检出点及污染严重点主要集中在城镇所在地及周边地区、河道两侧及工矿企业密集区;在垂向分布特征上,浅层地下水的有机污染程度较深层地下水严重,随着深度的增加,污染程度逐渐减弱。     

An extension to the DRASTIC model to assess groundwater vulnerability to pollution: application to the Haouz aquifer of Marrakech (Morocco)

An extension to the DRASTIC model is proposed in order to assess aquifer vulnerability to pollution. In contrast to the DRASTIC model, which considers the unsaturated and saturated zones together and computes a global intrinsic vulnerability index, the suggested approach discriminates between the aquifer vertical vulnerability (a concept related to the pollutant percolation) and the groundwater susceptibility (a concept that depends on the behaviour and uses of the groundwater). This approach is applied to the Haouz aquifer (Morocco) that supplies water to the Marrakech area. This aquifer is widely overexploited and there is evidence that the groundwater quality is threatened by various sources of pollution. Evaluation of the vertical vulnerability indicates that the aquifer mainly presents a moderate-to-weak vertical vulnerability. The zones potentially most favourable to pollutant percolation are mainly located in Central Haouz, along or near the surface wadis. The aquifer susceptibility is high in places located near the N’Fis, Baaja and Issil wadis. Everywhere else, low-to-moderate susceptibility is observed. This new approach therefore enables areas of vertical vulnerability and areas of susceptibility to be delineated separately. As a result, it constitutes a valuable decision-making tool for optimising the management of aquifer water resources and land-use planning.     

Delineation of spatial-temporal patterns of groundwater/surface-water interaction along a river reach (Aa River,Belgium) with transient thermal modeling

Among the advances made in analytical and numerical analysis methods to quantify groundwater/surface-water interaction, one methodology that stands out is the use of heat as an environmental tracer. A large data set of river and riverbed temperature profiles from the Aa River in Belgium has been used to examine the spatial-temporal variations of groundwater/surface-water interaction. Exchange fluxes were calculated with the numerical heat-transport code STRIVE. The code was applied in transient mode to overcome previous limitations of steady-state analysis, and allowed for the calculation of model quality. In autumn and winter the mean exchange fluxes reached ?90 mm d^?1, while in spring and early summer fluxes were ?42 mm d^?1. Predominantly gaining conditions occurred along the river reach; however, in a few areas the direction of flow changed in time. The river banks showed elevated fluxes up to a factor of 3 compared to the center of the river. Higher fluxes were detected in the upstream section of the reach. Due to the influence of exchange fluxes along the river banks, larger temporal variations were found in the downstream section. The exchange fluxes at the river banks seemed more driven by variable local exchange flows, while the center of the river was dominated by deep and steady regional groundwater flows. These spatial and temporal differences in groundwater/surface-water exchange show the importance of long-term investigations on the driving forces of hyporheic processes across different scales.     

Surface electrical resistivity tomography and hydrogeological characterization to constrain groundwater flow modeling in an agricultural field site near Ferrara (Italy)

A portion of an unconfined alluvial aquifer located in the Padana Plain (Italy) was characterized following an integrated hydro-geophysical approach. Initially an electrical resistivity tomography (ERT) survey was employed to localize the boundaries of a modest paleo-channel body and to design the installation of a groundwater monitoring network. Multilevel slug-tests were performed to estimate the aquifer’s saturated hydraulic conductivities. Determined permeability values together with electrical resistivity data were correlated. The correlation resulted in a site specific bi-logarithmic linear relationship. Based on this relationship, punctually determined hydraulic conductivities were spatially extended over the studied flow domain. Finally, continuously measured piezometric heads were used to calibrate a 3D flow model. Sensitivity analysis was performed to confirm the reliability of the reconstructed permeability field, as well as, to assess the minimum number of direct measurements needed to safely characterize the selected aquifer portion. The integration of the ERT survey results with the classical hydrogeological tests can be conveniently applied to constrain the permeability field during flow model calibration. Although the applicability of the determined relationship is site specific, the followed procedure is useful especially when there is a need to optimize the available resources and in case of small-scale pilot studies.     

浅议地下贮油库(罐)的防泄漏安全措施和地下水的污染防护

本文从泄漏石油及其产品在不同岩性非饱和带和地下水中的迁移特征和国内外油污染事故谈起,就目前城市地下油库（罐）的安全建设问题,介绍国外防止油库（罐）泄漏的技术措施和目前我国北京地区所采用的经济有效的防泄漏安全措施,以供推广应用     

Assessment of groundwater vulnerability to pollution: a combination of GIS, fuzzy logic and decision making techniques

The assessment of groundwater vulnerability to pollution aims at highlighting areas at a high risk of being polluted. This study presents a methodology, to estimate the risk of an aquifer to be polluted from concentrated and/or dispersed sources, which applies an overlay and index method involving several parameters. The parameters are categorized into three factor groups: factor group 1 includes parameters relevant to the internal aquifer system’s properties, thus determining the intrinsic aquifer vulnerability to pollution; factor group 2 comprises parameters relevant to the external stresses to the system, such as human activities and rainfall effects; factor group 3 incorporates specific geological settings, such as the presence of geothermal fields or salt intrusion zones, into the computation process. Geographical information systems have been used for data acquisition and processing, coupled with a multicriteria evaluation technique enhanced with fuzzy factor standardization. Moreover, besides assigning weights to factors, a second set of weights, i.e., order weights, has been applied to factors on a pixel by pixel basis, thus allowing control of the level of risk in the vulnerability determination and the enhancement of local site characteristics. Individual analysis of each factor group resulted in three intermediate groundwater vulnerability to pollution maps, which were combined in order to produce the final composite groundwater vulnerability map for the study area. The method has been applied in the region of Eastern Macedonia and Thrace (Northern Greece), an area of approximately 14,000 km². The methodology has been tested and calibrated against the measured nitrate concentration in wells, in the northwest part of the study area, providing results related to the aggregation and weighting procedure.     

Contamination of soil and groundwater at a former industrial site in Trondheim,Norway

This paper describes an investigation carried out in 1990 by the Geological Survey of Norway into the contamination of soils and groundwater at a former industrial site. The site covers an area of 0.5 ha and was used for a small plant generating gas for lighting purposes and from the middle of the last century for a small electrochemical facility (The Nidelven Brass and Iron Co. Est. 1843). The site is located immediately adjacent to the Nidelva river, in the central area of the city of Trondheim (pop. 150,000), Norway. Soil samples were obtained from 10 boreholes drilled to approximately 4 m depth. Analysis of the heavy metal content of these soil samples was subsequently undertaken. A subset of the samples was analysed for tar, including polycyclic aromatic hydrocarbons (PAH). The concentrations of Cd, Co, Cr, Hg, Ni and PAH in the soils are all below the maximum permissible levels recommended by the authorities. In certain localities, however, the concentrations of Cu, Pb and Zn are higher than the action levels at which remediation is required. It is estimated that approximately 4400 m³ of soil are contaminated, but that the contaminants are bound so tightly to the soil that the risk of dispersion of the pollutants is negligible.Groundwater samples were also collected from 4 monitoring wells installed at the site. Analysis of these groundwaters indicated the presence of only slightly contaminated groundwater. With the exception of 1 sample with a slightly higher concentration of Cu, the concentrations of PAH and the trace metals Co, Cr, Cu, Hg, Ni and Zn in the groundwater were below natural background values. This confirms the results from the soil analyses in which it was concluded that the dispersion of contaminants is negligible. A TCLP-extraction of 5 soil samples with high concentrations of Cu, Pb and Zn showed that only Zn was released in amounts exceeding the water guidance levels requiring monitoring.This study therefore indicates that the contaminants found in the ground at the site are strongly bound to the soil and are unlikely to be mobilised. This, combined with a slow base-flow, causes an insignificant contamination contribution to the waters in the River Nidelv. It should be noted, however, that the leaching experiments were not undertaken on the samples containing the highest Cu, Pb and Zn concentrations.     

广西某铅锌矿区水文地质及地下水重金属污染途径分析

文章在对广西某铅锌矿矿区水文地质条件分析的基础上,采用连通试验对地下水动态特征及其影响因素进行分析评价。实验结果表明,矿山区域地下水流经地下巷道携带大量重金属离子由废旧矿洞口排出地表,地表水流经地表废旧矿渣堆场携带大量污染物和矿洞水汇成溪沟,然后以地表径流方式污染长屯的土壤和水系,最终由长屯南伏流入口汇入洞零水库。尾矿库区域地下水通过地下岩溶管道和溶蚀裂隙向长屯洼地径流,经长屯南伏流入口,汇入洞零水库。