Ground-Water Protection Zones

In many areas, the water demand of households, industries and farms is satisfied by ground water. Because of many human activities ground-water quality decreases, it is necessary to protect it. The quantity of pollutants entering the aquifers can be minimized by technical and legal measures. But it seems to be almost impossible to solve the problem regionally or nationwide. The delineation of protection zones around existing or planned wells is a more effective way. The intake area of wells or well fields have to be protected by legal measures against all activities which may affect ground-water quality. Regarding the migration of viruses and bacteria, it is well known that these biological pollutants have a distinct limited lifetime in aquifers, which is for West Germany estimated at 50 days. Because during this limited time they can move with the ground water, transfer diseases, and cause epidemics, certain zones around wells must be kept free from activities which may introduce bacteria into the subsurface systems. These zones are generally smaller than the catchments. For the determination of the zones, careful studies and calculations of the distance-velocity of ground water are necessary. Primary methods are the use of tracers and simple calculations. Examples are given for calculating the distance to the 50-day line, based on West German experience.     

某油田地下水污染特征及其机理分析

在对某油田石油类污染物分布特征研究的基础上,对其进入地下水的途径进行分析。研究表明,除石油类外,CODMn、Cl-、NO3-N和TDS具异常变化,这些异常变化已成为石油类污染的参考指标。含水层污染程度主要以严重污染和中度污染为主,下段含水层中的石油类污染物的浓度明显高于上段含水层。地下水遭受污染的途径类型分为地表渗透型和优势通道渗漏型,但地表渗透型污染对研究区地下水的威胁性相对来说较小。由构造活动、地下水开采引发的地裂缝形成的优势通道渗漏型污染是地下水污染的主要途径。     

In situ arsenic removal in an alkaline clastic aquifer

In situ removal of As from ground water used for water supply has been accomplished elsewhere in circum-neutral ground water containing high dissolved Fe(II) concentrations. The objective of this study was to evaluate in situ As ground-water treatment approaches in alkaline ground-water (pH > 8) that contains low dissolved Fe (<a few tens of μg/L). The low dissolved Fe content limits development of significant Fe-oxide and the high-pH limits As adsorption onto Fe-oxide. The chemistries of ground water in the two aquifers studied are similar except for the inorganic As species. Although total inorganic As concentrations were similar, one aquifer has dominantly aqueous As(III) and the other has mostly As(V). Dissolved O₂, Fe(II), and HCl were added to water and injected into the two aquifers to form Fe-oxide and lower the pH to remove As. Cycles of injection and withdrawal involved varying Fe(II) concentrations in the injectate. The As concentrations in water withdrawn from the two aquifers were as low as 1 and 6 μg/L, with greater As removal from the aquifer containing As(V). However, Fe and Mn concentrations increased to levels greater than US drinking water standards during some of the withdrawal periods. A balance between As removal and maintenance of low Fe and Mn concentrations may be a design consideration if this approach is used for public-supply systems. The ability to lower As concentrations in situ in high-pH ground water should have broad applicability because similar high-As ground water is present in many parts of the world.     

浅析某油田地下水石油类污染途径

研究区处于东北某油田区,该油田已有近50年的开发历史。随着对石油需求的不断增加,大量的石油被开采了出来。但是在开采过程中由于对落地原油及开采过程中油田废水的处置不当,致使地下水遭受了污染。因此保护地下水免受进一步污染对当地居民的身体健康和人身安全都是非常必要的。笔者基于研究区水样测试的结果石油类污染物浓度等值线图,发现地下水中石油类污染小范围内呈面状分布外,主要呈点状分布于研究区。通过结合对研究区地质环境、构造背景、地表水流和污染源的大量调查研究,分析得出石油类污染物主要是通过由过量开采地下水引起的地裂缝和新构造断裂引发的地裂缝以及事故性污染到达地下水的。研究区的ZK6号井附近由于长期的超量开采地下水从而改变了地下水流向,在地表则形成了地面沉降并引发了此处的地裂缝,致使此地下水油类的污染非常严重。另外,新构造断裂在北西向、北北东向及东西向3组壳断裂带的基础上继承性运动,致使下伏含油层油气沿裂缝上窜污染上覆含水层,同时在油田地表发育大量的地沟、地裂缝,地表洒落的原油及其他污染物通过这些地裂缝污染含水层。     

Potential pollution of groundwater in the valley of the Seybouse River,north-eastern Algeria

In north-eastern Algeria, the Seybouse River is an important source of water used mainly for irrigation of large agricultural areas extending from the Guelma region to Annaba city. Industrial activities in this region contribute substantial water pollution to the river and the groundwater. Based on the different sources of pollution, mapping of areas vulnerable to groundwater pollution has been accomplished by combining land use and data on groundwater levels. The resulting maps show that the most vulnerable areas are those with large industrial activities—in Meboudja, Bouchegouf and Guelma. Infiltration and runoff contribute to pollution, and the highest infiltration rate is generally observed in areas of agricultural and industrial activities. Pollution of the aquifers in this area is of concern. Mountains, such as the Edough and Gelaat Bou Sbaa, contribute high runoff that carries pollutants towards the groundwater.     

Water quality and relationship between superficial and ground water in Rome (Aniene River basin,central Italy)

Chemical, physical, and biological features of streams and ground water of the North-Eastern area of Rome are jointly analyzed in order to assess the status of water resources. Ground water was investigated with classical survey methods (pH, temperature, and electric conductivity). Microbiological pollution, faunal composition, and stream surrounding area conditions of surface waters were studied, in order to quantify the residual value of these ecosystems from both a human and an environmental point of view. Results show a general impairment of the system and the comparison between superficial waters and shallow ground waters makes it possible to detect the presence of a connection between the two levels. This relationship occurs as an exchange from superficial waters (streams and rivers) to the shallow aquifers. Where superficial waters are contaminated, as in the Tor Sapienza stream, pollutants move to the shallow aquifers too, due to the decreased pressure of the over-exploited aquifer. Moreover, uncontrolled drilling activity, diffused in urban areas, makes it possible the connection between shallow and deep ground water. Notwithstanding this, the mixing between superficial and deep ground water system in Rome is not very widespread and, apparently, limited to restricted areas.     

Assessment and mapping of the intrinsic vulnerability to pollution: an example from Keritis River Basin (Northwestern crete, Greece)

Due to the geological and hydrogeological characteristics, the carbonate aquifers are frequently vulnerable to natural and/or anthropogenic polluting sources. The aim of the present study is to evaluate the intrinsic vulnerability to pollution of the Keritis River Basin (northwestern Crete, Greece). The huge amount of the flowing groundwater represents a strategic water resource to be allocated to drinking water purpose and to agricultural activities, too. The studied groundwater are characterized by quality degradation processes represented by the anthropogenic and natural pollution such as olive oil farming, agriculture activities, industrial waste and salt water intrusion. For a better management and protection of the water resources, the assessment and mapping of groundwater vulnerability to pollution are very important. From this investigation, the Keritis Basin showed an intrinsic vulnerability degree from extremely high to very low. This study allows to define the strategies which will permit a proper safeguard criteria, against the pollution sources of the Keritis Basin groundwater resources.     

内蒙古托克托县潜水与承压水中氟化物的空间分布特征及形成机理

氟是维持人体健康所必需的微量元素,过多或过少的摄入都会造成相应的健康问题。本研究从氟的来源、迁移和富集等角度,揭示了内蒙古呼和浩特市托克托县高氟地下水的空间分布规律及其在潜水和承压水中富集的原因。对研究区60个水样(30个潜水和30个承压水)进行了统计分析、水化学特征研究、聚类分析以及相关性分析。结果表明：潜水中F^- 浓度为0.40~7.20(2.30±1.80) mg/L,承压水中F^- 浓度为0.29~12.70(1.67±2.48) mg/L;地下水中F-浓度与HCO^-₃、Na⁺、溶解性总固体(TDS)和电导率(EC)呈正相关,与Ca²⁺呈一定的负相关关系。高氟水的水化学类型主要为HCO₃·Cl-Na型。受地下水流场的控制,高氟潜水(>5 mg/L)主要分布在地下水的排泄区;承压水中F^- 的富集主要受含水层岩性的影响,氟高浓度(>1.5 mg/L)分布区主要集中在研究区南部的湖积台地区域。     

Use and availability of ground-water

Every man has to consume a certain quatity of water every day. This use constitutes the most basic need for water. In households water is also used for basic hygiene, washing, cleaning, and for the transport of sewage. Water is used in industry for cooling, generating electric power, for the production of a large variety of goods, and other purposes. The greatest demand for water results from irrigation. To satisfy these demands, an increasing quantity of ground-water is used. It is available at many places, where far extended subsurface reservoirs exist; it is better protected against pollution than surface water. But even though ground-water exists in many geological formations, which seem to be infinite, the availability is limited. The recharge of ground-water is dependent on the supply of atmospheric moisture. Especially in semiarid and arid zones this component of the hydrologic cycle determines the availability of ground-water. Besides natural conditions, technical and economic factors such as drilling of boreholes and the cost of pumping of ground-water have to be considered. Also political decisions can limit the availability of ground-water. If, for instance, wetlands are destroyed by drawdown of ground-water, nontechnical and non-economical aspects are involved. We face undesirable effects of ground-water pumping. Whether these effects are tolerable or intolerable depends on the decision-making processes on a political level.     

桂江流域地下水污染途径及防控措施研究

对桂江流域开展岩溶地下水污染调查发现:流域内地下水污染源分为“三氮”污染源、重金属污染源、有机污染源三类;“三氮”污染源主要包括工业、养殖和生活三类污水、生活垃圾渗滤液、农业施用氮肥等;重金属污染主要来自工矿企业;有机污染来自工业、养殖业。污染途径主要有孤峰平原的分散入渗式、孤峰平原的脚洞灌入式、峰丛洼地的消水洞灌入式、溶丘谷地的入渗式和峰丛峰林谷地的天窗灌入式等五类。并对88组地下水样品测试结果进行多指标地下水污染综合评价,结果表明36.5%的水点为“三氮”污染,多以分散入渗进入地下水,其污染形态呈面状分布;15.3%的水点为重金属污染,主要通过峰丛洼地消水洞灌入式补给和溶丘谷地入渗补给两种途径,呈点状分布于污染场地附近;3.49%的水点为有机污染,主要为分散入渗补给途径,污染呈短线状或点状分布。      

Estimation of environmental impacts on the water quality of the Tahtalıdam watershed in İzmir, Turkey

Water pollution is a widespread problem in different areas of the world. Some of these problems originated from point contamination sources and widespread contaminant outlet sources which are observed in every country. The major elements and chemical loads of surface water have been dominated by constituents derived directly or indirectly from human activities and/or industrial practices that have increased additives in the last several decades. The point sources of contamination may result from the direct wastewater discharges to the dam sites, which are considered to be the most commonly encountered water pollution problems. One of these problems is the eutrophication process which usually occurs in the static water mass of lakes and other surface water reservoirs. This process may be caused by the continuous increase of nitrogen and phosphorus contents and decrease of O₂ level in water causing an anaerobic condition which may stimulate algae-growth flow in these water bodies, consequently reducing the quality of water. Of course, there are many research methods for determining the various kinds of water pollution. In this research, the hydrochemical parameters were evaluated to estimate the types of pollution sources, the level of pollution, and its environmental impacts on the Tahtal dam reservoir.     

Geologic, hydrologic, and geochemical interpretations of mineral deposits as analogs for understanding transport of environmental contaminants

Base- and precious-metal mineral deposits comprise anomalous concentrations of metals and associated elements, which may be useful subjects for study as analogs for migration of environmental contaminants. In the geologic past, hydrothermal mineral deposits formed at the intersection of favorable geologic, hydrologic and geochemical gradients. In the present, weathering of these sulfide-rich deposits occurs as a result of the interplay between rates of oxygen supply versus rates of ground or surface-water flow. Transport and spatial dispersion of elements from a mineral deposit occurs as a function of competing rates of water flow versus rates of attenuation mechanisms such as adsorption, dilution, or (co)precipitation. In this paper we present several case studies from mineralized and altered sedimentary and crystalline aquifers in the western United States to illustrate the geologic control of ground-water flow and solute transport, and to demonstrate how this combined approach leads to a more complete understanding of the systems under study as well as facilitating some capability to predict major flow directions in aquifers.     

扬-泰-靖地区地下水系统水力联系与硫酸盐污染特征

本文对长江三角洲扬-泰-靖地区第四系松散层地下水中环境同位素(D、18O、34S)的分布特征进行了分析,旨在揭示大气降水、长江水、潜水及承压水之间的水力联系,辨别地下水中硫酸盐的来源及其污染状况。研究结果表明潜水含水层接受大气降水及长江水的补给,硫酸盐主要为农业污染来源或与海源硫酸盐的混合。承压含水层主要接受大气降水的补给,与潜水含水层及长江之间的水力联系较差,硫酸盐来源不同。在研究区顶部和沿江地段的浅层孔隙承压水中,硫酸盐来源于硫化物的氧化;在东部的深层孔隙承压水中,硫酸盐主要来源于硫酸盐岩的溶解或海源硫酸盐的滞留,基本未受到潜水或地表水中硫酸盐的污染。     

APPLICATION OF THE GEOBOTANICAL METHOD IN HYDROGEOLOGIC STUDIES OF DESERTS AND SEMIARID REGIONS

Plant associations in arid and semiarid regions serve as indicators not only of presence of ground water, but of its depth, relative salinity and seasonal variations. Plants such as phreatophytes may serve as direct water indicators, while Anabasis salsa, an indirect water indicator, is more indicative of geologic conditions, in this case clayey or argillaceous soils. An Anabasis salsa association in the Temirsk-Aktyubinska Ural region indicates that the ground water is located at considerable depth; in the northwestern Caspian area, however, this same association is often found in low wastelands forming localized impermeable horizons where ground water may be found at depths of 5 to 10 m. Some associations indicate the degree of salinity, rather than ground-water depth. Preparation of a ground-water resources map from such geobotanical data requires field work, during which associations around known wells, ponds or ground-water areas are analyzed to provide a criteria for the area as a whole. It has been found that data from field studies tally closely from that made from aerial photographs. Hence, after initial studies are made, prospecting of a given region may be carried out by aerial photographs. Variations in vegetation relative to depth and mineralization of ground water also may be used to forecast changes in the vegetation which would occur following construction of an irrigation system. --A. Eustus.     

Groundwater quality of porous aquifers in Greece: a synoptic review

Greece is dependent on groundwater resources for its water supply. The main aquifers are within carbonate rocks (karstic aquifers) and coarse grained Neogene and Quaternary deposits (porous aquifers). The use of groundwater resources has become particularly intensive in coastal areas during the last decades with the intense urbanization, tourist development and irrigated land expansion. Sources of groundwater pollution are the seawater intrusion due to over-exploitation of coastal aquifers, the fertilizers from agricultural activities and the disposal of untreated wastewater in torrents or in old pumping wells. In the last decades the total abstractions from coastal aquifers exceed the natural recharge; so the aquifer systems are not used safely. Over-exploitation causes a negative water balance, triggering seawater intrusion. Seawater intrusion phenomena are recorded in coastal aquifer systems. Nitrate pollution is the second major source of groundwater degradation in many areas in Greece. The high levels of nitrate are probably the result of over-fertilization and the lack of sewage systems in some urban areas.     

Experimental study and numerical simulation of soil water and salt transport under dry drainage conditions

Coal mining has serious impacts on local environment, including damage to the land and soil by subsidence, damage to ground-water systems through the fracturing and subsiding of overlying rocks, contamination of surface waters with acid mine drainage, and pollution of the atmosphere by release of toxic gases. The damage to ground water and its consequent impacts on the regional environment is the core of research of the coal mining from the perspective of environment protection. The present paper focuses on the changes of surface vegetation coverage, the pollutants released from pit coal power plants, and the damages to the ground aquifers induced by mining activities in arid Eastern Junggar coalfield of China. At first, the authors investigated the changes of surface vegetation coverage, since mining began in the 2000s using Landsat data. Results show that the low surface vegetation coverage (grade 1 plus grade 2) in the southern part of the region decreased from 11.62?×?10⁸ m² in 2003 to 9.57?×?10⁸ m² in 2017 (?17.6%), while it increased from 11.58?×?10⁸ m² in 2003 to 12.70?×?10⁸ m² in 2017 (+?9.7%) in the eastern part. The high surface vegetation coverage (grade 3 plus grade 4) in the southern part increased from 1.94?×?10⁸ m² in 2003 to 4.00?×?10⁸ m² in 2017 (+?106.2%), while it decreased from 4.39?×?10⁸ m² in 2003 to 3.26?×?10⁸ m² in 2017 (?25.74%) in the eastern part. The data of annual precipitation during the same period in this area show that the changes of surface vegetation coverage have less relationship with the annual precipitation, which indicates that the mining activities is probably the major factor for that. Second, a statistic of air pollutants generated from pit coal power plants was made based on data of references. Results show that the estimated gaseous pollutant emissions increased as 865.23 tons of smoke particles, 5940.73 tons of SO₂, and 7584.48 tons of NO₂ in 2013, which increased rapidly with 9.73 times the smoke particle, 21.69 times the SO₂, and 9.24 times the NO₂ than that of 2007. And then, the physical and numerical simulation of the damage of mining activities to aquifers was made to show the permeability of the reference points of overlying aquifers varies associated with mining activities. Results show that the porous rock matrix permeability has a negative relationship with fluctuation during mining, while the fracture permeability shows a positive one. Finally, a case investigation in southern area surrounding this coalfield was illustrated. Result shows that the local ground-water level decreased by 16 m difference from the altitude level of?+?774 m in 2003 to?+?758 m in 2013. Data and results from this study presented the already and the potential pollutions and damages to local environment induced by the mining activities in this region.

     

生活垃圾对环境的污染评价方法探讨

生活垃圾对环境的污染，主要表现为垃圾渗滤液对地面水、地下水、土壤等的污染。其污染评价涉及污染物指标、污染物标准值的确定和计算模式的建立等内容。本文在总结现行环境指数评价法的基础上，探讨性地提出一套将基于生活垃圾填埋场环境监测技术标准(CJJ／T3037—95)中涉及地面水、地下水、土壤等的相关监测项和垃圾中的其他常见重要污染物，一并确定出的污染评价指标，再根据相关有毒物急性毒性分级，结合阈限值和部分浸出毒性鉴别标准值等分为5类污染指标。并在污染物的标准值确定后，进行对应于5类污染物的不同数学模式计算，得到5个分类污染指数，再比较判别这5个分类污染指数，选出最大者作为总污染指数的组合型评价垃圾污染的方法。经实例应用分析，该方法对各种污染物数据分布情况的适宜性优于现行其他常用方法。     

贵州主要碳酸盐岩含水层污染现状与特征

岩溶地区地下水环境脆弱,易受人类活动及区域环境变化影响.目前将岩溶水污染与污染点所在区域的地层岩性、水文地质条件等结合起来的研究较少.采用改进后的层级阶梯评价法开展贵州省区域地下水污染评价,并结合实地调查分析污染成因.结果显示二叠系栖霞-茅口组,三叠系下统嘉陵江组、夜郎组等,中统关岭组、杨柳井组等是全省污染程度最高的碳酸盐岩含水层,原因与含水层岩石类型和出露位置密切相关.含水层岩石类型与特点决定了含水介质组合类型、岩溶发育程度和污染途径污染距离,石灰岩地层天然防污能力差,以中远源径流型污染为主,白云岩地层天然防污能力较好,以近源入渗型污染为主.贵州产煤地层龙潭组上覆嘉陵江组、夜郎组,下伏栖霞-茅口组最易受煤矿开采及其化工影响,污染组分以铁、铝、锰为主;而三叠系碳酸盐岩分布区域与安顺、贵阳、遵义等大中型城市和磷化工、铝工业、锰系铁合金生产等工矿企业聚集区域重合度高,更容易受到生产生活影响,污染组分多为氨氮、重金属、耗氧量及有机污染组分.      

Changes of the geological environment of the Northern Black Sea region and the chemicalization of agricultural production

The generalization of the data available, field and laboratory investigations made it possible to estimate the pesticide inflow with large rivers to the NW part of the Black Sea, and the degree of pollution of the soil cover, bottom sediments of water bodies, confined aquifers with pesticides and ground water with nitrates. As a result of the uncontrolled use of agrochemicals their residual quantities were found in 66–93% of the samples. In connection with economic activities the greatest damage was caused to the ground water — the main source of water supply in the region: in some areas the depletion of their resources, intrusion of sea water and salt ground waters into aquifers as well as presence of residual quantities of pesticides in concentrations exceeding the maximum permissible limit were detected.Ideas on limitation of the harmful impact of agrochemicals upon the region's environment are presented here.     

重工业区高脆弱岩溶含水层中多环芳烃污染的初步研究

以西南岩溶地区某市重工业区为研究对象,采集水文地质单元内地下水和土壤样品,利用气相色谱-质谱法（GC-MS)测试美国环保署16 种多环芳烃（PAHs）优控物。初步研究表明,研究区地下水16种PAHs均被检出,浓度为1 135.79～1 361.26 ng/L,以菲、蒽、萘、屈、芘为主;地下水处于中等污染程度,其中苯并[a]蒽、屈、苯并[b]荧蒽、苯并[k]荧蒽4种浓度超过美国EPA2009《国家推荐的优先有毒污染物水质标准》标准;PAHs特征比值显示含水层中的PAHs来源于燃煤和炼焦污染源,与钢铁厂和化肥厂排放的特征有机污染物一致。研究区污染源下游大面积区域地下水已经受到PAHs污染,且出现排泄区PAHs浓度高于径流区的现象,岩溶含水层PAHs的污染主要受两方面影响:一是洼地、裂隙发育,断层破碎带和强风化白云岩等为PAHs在含水层中的运移提供了有利条件,同时污染源区内地下水大量开采加速了污染物向地下水的入渗;二是水电站建坝蓄水发电,江水水位抬高,河岸地下水排泄速度减慢,可能致使岩溶含水层中PAHs的自净能力减弱。生态风险评价显示地下水中菲、蒽、芘、苯并[a]蒽、苯并[b]荧蒽处于重污染风险,应采取措施降低污染风险。