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1.
环境调查研究表明,大武地下水水源地上游邻近的石化厂区出现严重的地下管道石油污染物持续泄漏现象。堠皋-柳杭地段地下水环境在成为集中污染地段的同时,水文地球化学环境也发生了迥然的变化:地下水中电子接受体溶解氧,NO3^-末检出,SO4^2-呈低值分布。这与地下水中存在微生物降解烃污染物的作用有关。其作用类型包括需氧降解,脱硝降解,脱硫降解以及有Fe^3+参与的降解作用。然而由于该地段需氧降解、脱硝降解、脱硫降懈以及有F3+参与的降解作用。然而由于废地段需氧降解、脱硝降懈难以进行,导致了生物降解污染物的速度降低 其研究意义是提高地下水中电子接受体的浓度.增强微生物的活性,以促进生物降解速度,将有利于含水层中这类污染物的清除。  相似文献   

2.
大武水源地地处山东省淄博市,区内建有某大型石化基地。水源地断裂带附近地下水曾受到来自地面石油化工污染物影响,亟需针对性治理修复。精准确定开采背景下岩溶水的实际流向、径流速度和渗透系数等关键参数是污染治理研究的关键。基于国际新兴的井孔地下水胶体探测技术,在该水源地断裂带污染段布设7眼探测孔,开展21个层位的原位系列探测,应用优势流理论和地质统计学方法确定关键水动力参数。结果表明:(1)大武岩溶水源地断裂带附近含水层强径流层位(易污染段)位于奥陶系八陡组下部(O2-3b)至奥陶系阁庄组(O2g)上部地层,65 m以浅的侧向流入补给是该水源地岩溶地下水污染的主要来源;(2)该水源地断裂带附近岩溶地下水具有多元质点流向,不同区段或层位实际水流方向和流速差异较大,揭示了断裂带对水源地的非单一层位影响,指明了水力屏障井混合开采的不利影响;(3)建议调整水力屏障井的抽排层位与强度,加强70 m以浅的抽排强度,使得SW95正西方向上的径流流速明显小于50.30 m/d;减小80~110 m深度的抽排强度,使得SW99正西方向上的径流流速明显小于49.38 m/d。  相似文献   

3.
In order to protect public supply wells from a wide range of contaminants, it is imperative to understand physical flow and transport mechanisms in the aquifer system. Although flow through fractures has typically been associated with either crystalline or carbonate rocks, there is growing evidence that it can be an important component of flow in relatively permeable sandstone formations. The objective of this work is to determine the role that fractures serve in the transport of near-surface contaminants such as wastewater from leaking sewers, to public supply wells in a deep bedrock aquifer. A part of the Cambrian aquifer system in Madison, Wisconsin (USA), was studied using a combination of geophysical, geochemical, and hydraulic testing in a borehole adjacent to a public supply well. Data suggest that bedrock fractures are important transport pathways from the surface to the deep aquifer. These fractured intervals have transmissivity values several orders of magnitude higher than non-fractured intervals. With respect to rapid transport of contaminants, high transmissivity values of individual fractures make them the most likely preferential flow pathways. Results suggest that in a siliciclastic aquifer near a public supply well, fractures may have an important role in the transport of sewer-derived wastewater contaminants.  相似文献   

4.
In this paper, the hydraulic characteristics of the fracture-karst aquifer and the distribution patterns of petrochemical contaminants are studied. Then, a numerical model using the mixed Eulerian-Lagrangian approach is constructed to predict the distribution and transport of petrochemical compounds in groundwater. The results of numerical modelling and sensitivity analysis show that it may be a workable way for aquifer remediation to combine contamination sources control and capture zone establishment.  相似文献   

5.
The risk of groundwater contamination following the infiltration of waste surface water, is of great interest, particularly in areas experiencing water shortage. In this study, the distribution characteristics of contaminants along the Cihe River, in the piedimont plain of the Taihang Mountains, China, was investigated by measuring the soil and water samples. The main organic contaminants detected in different media include hydrocarbons, chlorinated hydrocarbons, polycyclic aromatic hydrocarbons, and pesticides. The main contaminants found in different media are mostly derived from the river water, which can be seen from the results of waste water from the river and groundwater, from the soil samples from different depth and distance of the profiles along the river. The distribution characteristics showed that there has been a natural attenuation of the contaminants from the river during their transportation through the soils and groundwater. The sorption of organic compounds to soil organic matter is thought to be a main mechanism of natural attenuation.  相似文献   

6.
Due to growing water extraction for industry and agriculture, the Dawu Water Supply Base, in the east of Zibo, China, has been in a state of serious over-extraction. It will also be affected by the deep drainage of the Dianzi Iron Mine, which will be exploited in 2005. As to the environmental impact on the groundwater system of the Dawu Water Supply Base is concerned, this paper makes a systematic study about the influence of the mine draining on the water-supply environment of the Dawu Water Supply Base by using the numerical model of groundwater system. The result shows that the groundwater level will have an additional drawdown of 1.2–1.8 m/yr by the mine draining alone. The numerical analysis results indicate that the optimal model for determining the best extraction plan is the solution for the contradiction between water supply and water drainage.  相似文献   

7.
JR-121井位于北京市定福庄南里,开采蓟县系雾迷山组1600m以深热储层的岩溶裂隙水。该试验井施工使用GZ-2000型水源钻机,TBW-850/50型泥浆泵,钻探深度2202.98m。成井过程中,根据不同层段,采用不同成井工艺,在目的含水层的上覆非取水层段,采用分级下套管及水泥封闭的方法进行止水,泥浆与回旋方法钻进;在取水段,采用裸眼孔底钻铤加压、泥浆护壁与回旋钻进。洗井工艺上,采用酸化、液态CO2和空压机引喷相结合的联合洗井方法。使用此成井工艺,止水效果良好,达到了开发岩溶裂隙地热水的目的。  相似文献   

8.
南水北调中线工程供水后对河南省受水区浅层地下水位、用水结构等产生了重要影响。首先回顾了河南省平原区以往地下水位埋深变化,并通过收集、统计2008—2018年河南省受水区浅层地下水位的监测成果,基于ArcGIS软件,针对南水北调中线供水前后河南省受水区浅层地下水位变化进行量化分区;结合降水量、地下水资源量、供水量等资料对供水前后河南省受水区用水结构变化等进行分析。结果表明:自20世纪60年代至2008年,河南省平原区浅层地下水位平均埋深整体逐渐增加;河南省受水区地下水资源量随降水量增加呈线性增加趋势;南水北调中线一期供水后,2015—2018年平均地下水供水量在地下水资源量中的占比较2008—2014年减少9.55%;受水区浅层地下水位有所回升,且主要体现在埋深 > 8~12 m范围向埋深 > 4~8 m及≤4 m范围的转变,埋深 > 12~16 m及 > 16~20 m范围在受水前后基本保持不变,埋深 > 20 m的区域范围有所减少;2008—2014年各监测点分布县区的浅层地下水位呈下降趋势,2015—2018年供水期间有2/3以上县区浅层地下水位逐渐恢复;农林渔业用水和工业用水占比在供水后均有所减小,城乡生活、环境综合用水占比增加明显。研究结果表明南水北调中线工程对河南省受水区浅层地下水位恢复及缓解供水矛盾问题等产生积极有效的影响。   相似文献   

9.
The layer of water-bearing sandstone (PR2 V kt1) named Lower-Kotlin aquifer is widespread in the northwestern part of the Russian platform, within the Moscow Artesian Basin. It is mostly confined. The aquifer lies directly on the surface of the crystalline basement throughout the basin. The water mineralization rises from north to south together with the depth of the aquifer. The mineralization growth is mainly caused by the increase of sodium and chloride contents. Three consequent vertical zones can be marked out: fresh-water zones (<1 g/dm3), brackish-water zone (1–35 g/dm3) and brine zone (>35 g/dm3). Each of these zones has specific regularities of variation of chemical composition. The role of each component is different for waters of each zone. The aquifer is actively exploited—for public water supply and bottling in the north and for mineral water treatment in the south. Within St. Petersburg, this water is used for technical purposes of industry. There are some health resorts and spas in St. Petersburg Region, such as Sestroretsk, Peterhof, Luga, which use the mineral water of the Lower-Kotlin aquifer. A number of bottling plants produce bottled mineral water. Wide regional location and peculiarities of chemical composition of the Lower-Kotlin aquifer cause the possibility of the organization of many other spas and health resorts near St. Petersburg.  相似文献   

10.
经过野外现场调查和取样分析及室内研究得知南阳油田地下水已遭受不同程度的有机物污染,且污染范围可能进一步向油田南部扩散。根据近似地下水流线方向上地下水中总油质量浓度和Fe,Mn等无机组分的变化势态,结合含水介质化学分析结果,发现硫酸盐、Fe和Mn可作为地下水有机污染和地球化学标志物。在含水介质中Fe和Mn质量浓度较高的地方,地下水有机污染物降解速度快,含水介质中Fe和Mn的氧化物和氢氧化物的还原作用导致了含水层介质中Fe和Mn的缺乏和地下水中溶解Fe和Mn的积聚;在含水介质中Fe和Mn质量浓度低的地方,地下水中的有机物质量浓度并没有降低,相应地地下水中溶解Fe和Mn的质量浓度也很低。同时,由于有机污染物的存在使地下水中硫酸盐被还原,导致城下水中硫酸盐质量浓度偏低,且地下水中Fe对有机物污染的敏感性比Mn强。  相似文献   

11.
Wells along two regional flow paths were sampled to characterize changes in water quality and the vulnerability to contamination of the Memphis aquifer across a range of hydrologic and land-use conditions in the southeastern United States. The flow paths begin in the aquifer outcrop area and end at public supply wells in the confined parts of the aquifer at Memphis, Tennessee. Age-date tracer (e.g. SF6, 3H, 14C) data indicate that a component of young water is present in the aquifer at most locations along both flow paths, which is consistent with previous studies at Memphis that documented leakage of shallow water into the Memphis aquifer locally where the overlying confining unit is thin or absent. Mixtures of young and old water were most prevalent where long-term pumping for public supply has lowered groundwater levels and induced downward movement of young water. The occurrence of nitrate, chloride and synthetic organic compounds was correlated to the fraction of young water along the flow paths. Oxic conditions persisted for 10 km or more down dip of the confining unit, and the presence of young water in confined parts of the aquifer suggest that contaminants such as nitrate-N have the potential for transport. Long-term monitoring data for one of the flow-path wells screened in the confined part of the aquifer suggest that the vulnerability of the aquifer as indicated by the fraction of young water is increasing over time.  相似文献   

12.
徐州矿区奥灰岩溶水突出的原因与防治   总被引:6,自引:0,他引:6  
徐州矿区开采深度大,水文地质条件复杂,水害严重。主要突出水源为奥陶系含水层。突水原因主要有:底板隐伏陷落柱或断层导水;底(顶)板含水层与奥灰含水层对接;顶板冒落裂隙带导通断层对盘的奥灰含水层;奥灰水通过基岩隐伏露头侧向补给矿井。其防治对策为:引进先进技术手段,探查分析奥灰岩溶水发育规律;分区隔离开采,完善防排水系统;注浆封堵突水通道;排供结合,综合利用。   相似文献   

13.
为了有效提升大清河流域平原区地下水水位,亟需在此区域开展地下水人工补给工程,并确定合理的建设位置及有效的补给方式。首先基于研究区可利用补给水源、地下水位、地表高程、地表坡度及与河道距离5个指标的分布特征,构建地下水补给潜力评价体系,采用ArcGIS空间分析功能对研究区进行了地下水人工补给潜力区划;然后在此评价体系基础上,在典型人工补给高潜力区进一步开展系列野外现场试验,探讨适宜可行的地下水人工补给方式。结果表明:研究区西北部及南部河道附近区域开展人工补给工程潜力较高,而中部、北部及西南部远离河道的区域潜力较低。高潜力区——白沟引河地段包气带及含水层渗透性良好,整体渗透系数均在5 m/d左右或更高,适宜地表补给,但河床渗透性较差,渗透系数基本在0.01~0.09 m/d间,若通过河道补给需配合清淤等措施。其中,在上游及中游沿岸适宜将河道水通过生态水渠引至修建的地表入渗池或借助天然渗坑内入渗补给,在中下游沿岸区域适宜将补给水进行严格的水处理后采用井灌方式补给,在白沟引河中下游河道适宜修建拦水坝,利用河道进行入渗补给。  相似文献   

14.
王维平  徐玉  何茂强  曹彬 《中国岩溶》2010,29(3):325-330
通过监测和分析济南市市区降水、屋面雨水水质和水量过程,屋顶雨水属微污染类水,经前期雨水弃流和预处理达到一定质量标准,通过管井回灌到裂隙岩溶含水层,可用于饮用水供水和保护地下水环境。已做的示踪试验表明,北方岩溶含水介质多属多重裂隙岩溶通道,因此在人工开采条件下,回灌应关注快、慢速流带来的不同水质变化问题,包括屋面雨水与裂隙岩溶介质的水岩作用。澳大利亚的案例说明,裂隙岩溶含水层对不同污染物有着不同的衰变效果。100多年来Mount Gambier市城区雨洪水经非承压石灰岩含水层径流一直排放到作为城市供水的蓝湖,到目前它对蓝湖水质没有表现出任何可量度的损害。但对于济南市的屋顶雨水回灌裂隙岩溶含水层,仍有许多问题需要研究。   相似文献   

15.
 Estimation of aquifer parameters is vital for the assessment of groundwater potential and groundwater flow regime. On an oceanic island where fresh water lens is fragile and sensitive to various stresses, it is even more essential that in order to assess the potential of fresh water lens and the effect of various stresses on the fresh groundwater regime the parameters should be representative to the field hydrogeological set up. Pumping tests conducted on existing large diameter wells on an oceanic island have been analyzed. A finite difference method has been used to take into account the well storage, partial penetration and upconing effect into the aquifer. Forward modeling has been carried out to estimate aquifer parameters from the pumping test data. Field examples are described. Received: 15 June 1998 · Accepted: 25 August 1998  相似文献   

16.
The present research aims to derive the intrinsic vulnerability of groundwater against contamination using the GIS platform. The study applies DRASTIC model for Ahmedabad district in Gujarat, India. The model uses parameters like depth, recharge, aquifer, soil, topography, vadose zone and hydraulic conductivity, which depict the hydrogeology of the area. The research demonstrates that northern part of district with 46.4% of area is under low vulnerability, the central and southern parts with 48.4% of the area are under moderate vulnerability, while 5.2% of area in the south-east of district is under high vulnerability. It is observed from the study that lower vulnerability in northern part may be mostly due to the greater depth of vadose zone, deeper water tables and alluvial aquifer system with minor clay lenses. The moderate and high vulnerability in central and southern parts of study area may be due to lesser depth to water tables, smaller vadose zone depths, unconfined to semi-confined alluvial aquifer system and greater amount of recharge due to irrigation practices. Further, the map removal and single-parameter sensitivity analysis indicate that groundwater vulnerability index has higher influence of vadose zone, recharge, depth and aquifer parameters for the given study area. The research also contributes to validating the existence of higher concentrations of contaminants/indicators like electrical conductivity, chloride, total dissolved solids, sulphate, nitrate, calcium, sodium and magnesium with respect to groundwater vulnerability status in the study area. The contaminants/indicators exceeding the prescribed limits for drinking water as per Indian Standard 10500 (1991) were mostly found in areas under moderate and high vulnerability. Finally, the research successfully delineates the groundwater vulnerability in the region which can aid land-use policies and norms for activities related to recharge and seepage with respect to existing status of groundwater vulnerability and its quality.  相似文献   

17.
 The Dawu well field, one of the largest in China, supplies most of the water for the Zibo City urban area in Shandong Province. The field yields 522,400–535,400 m3/d from an aquifer in fractured karstic Middle Ordovician carbonate rocks. Much of the recharge to the aquifer is leakage of surface water from Zihe Stream, the major drainage in the area. Installation of the Taihe Reservoir in 1972 severely reduced the downstream flow in Zihe Stream, resulting in a marked reduction in the water table in the Dawu field. Since 1994, following the installation of a recharge station on Zihe Stream upstream from the well field that injects water from the Taihe Reservoir into the stream, the groundwater resources of the field have recovered. An average of 61.2×103 m3/d of groundwater, mostly from the Ordovician aquifer, is pumped from the Heiwang iron mine, an open pit in the bed of Zihe Stream below the Taihe Reservoir. A stepwise regression equation, used to evaluate the role of discharge from the reservoir into the stream, confirms that reservoir water is one of the major sources of groundwater in the mine. Received, May 1998 / Revised, May 1999 / Accepted, June 1999  相似文献   

18.
武汉-1超深地热井钻井成井工艺   总被引:2,自引:0,他引:2       下载免费PDF全文
丁同领  高翯 《探矿工程》2012,39(8):23-25
根据设计要求及地质特征,武汉-1超深井采用回转钻进、泥浆泵正循环、牙轮钻头钻进、钻铤给压钻进工艺,采用合理的钻探技术参数保证地热井结构及垂直度符合设计要求,并对泥浆进行降密度、提粘、提切并加入适量堵漏剂的方法堵漏,取得了良好效果。抽水试验说明该井出水能力较强,热储层含水层富水性较好,且水温不受气温影响,在井流试验过程中水温损失所占比例较小,证明了本井的钻井和成井技术是合理的。介绍了武汉-1井的钻井成井工艺及抽水试验成果。  相似文献   

19.
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   

20.
A hydrogeological study has been carried out in Antalya travertine basin for the future domestic water supply of Antalya. Geological formations that could be used as an aquifer have been identified, and a hydrogeological map has been prepared. Water-quality analyses show that groundwater has been and is being contaminated by sewage discharge, industrial works, and other activities that create an ever-expending impact to the only available aquifer. Something should be done immediately to protect the aquifer from additional degradation. Received: 28 April 1998 · Accepted: 18 August 1998  相似文献   

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