Impact of Tanning Industries on Groundwater Quality near a Metropolitan City in India

The present study was carried out with the objective of determining the extent of groundwater pollution caused by tanning industries in Chromepet area located south of Chennai, Tamil Nadu, India. Groundwater samples were collected during January and March 2008 from 36 wells and were analysed for the concentration of various major ions and chromium. Na-Cl was the dominant water type found in this area. Groundwater in this area is not suitable for drinking as it contains elevated concentration of most major ions and chromium. This is due to the recharge of partially treated effluent discharged by tanning industries into open drains. The concentration of chromium was above the permissible limit (0.05 mg/l) in 86% of the groundwater samples. The use of chemicals, such as sodium chloride, sodium sulphate, chromium sulphate etc. during the tanning processes is the major reason for the high concentration of major ions and chromium in groundwater. Hence it is important to regulate the industries and also take measures to reduce the total dissolved solids in the treated effluent before disposal. The groundwater quality of this region can also be improved by adopting rainwater harvesting thereby increasing groundwater recharge.     

Groundwater Quality Zonation Assessment using GIS, EOFs and Hierarchical Clustering

Three methods are utilized in this paper to assist in the groundwater clustering, in an arid region aquifer, into similar zones according to its quality. A multiple regression is first applied in order to assess the importance of the different chemical constituents in the amount of total dissolved salt, which shows the dominance of chlorine and sodium. A multivariate analysis based on empirical orthogonal functions and hierarchical clustering (EOFs) is applied to assist in water quality clustering in the studied aquifer. The clustering has produced five distinguished categories of groundwater quality, which agree well with World Health Organisation criteria and limits for water usage. Based on these categories, spatial distribution maps of groundwater quality are produced by Kriging and GIS software.     

白城市地下水质量现状评价

根据吉林省白城市境内选取的9个测点地下水指标的实测数据,对白城市地下水质量现状进行评价。选取的评价指标分别为氨氮、铁、氟化物、铅、砷、高锰酸钾、矿化度、硬度。评价方法分别采用加附注评分法与人工神经网络法,其中人工神经网络法选用BP神经网络、T-S模糊神经网络2种方法。评价结果显示:2种人工神经网络法评价的水质类别均在Ⅰ～Ⅲ类之间,水质较好;加附注评分法评价出的水质类别中只有穆家店屯水质属于Ⅱ类,其他测点均为Ⅳ类。对比3种方法评价的结果可知,BP神经网络与模糊神经网络评价的水质类型之间的差异较小,加附注评分法比其他2种方法评价得出的水质类别大。     

城市固体垃圾炉渣的三轴试验研究

炉渣是城市固体垃圾焚烧后的产物,可以代替骨料作为路基垫层材料使用,实现资源的二次利用。为了研究炉渣在路基填筑过程中的强度以及变形特征,对干密度ρ_d分别为1.4, 1.5, 1.6 g/cm³、龄期t分别为3, 7, 14, 28 d的饱和炉渣试样进行不同围压下的三轴固结排水试验,通过Lambe平面方法确定炉渣的抗剪强度参数(黏聚力、内摩擦角)。研究结果表明:在低围压下(100,200 kPa),城市固体垃圾炉渣的应力-应变曲线呈现应变软化特性;随着围压增大硬化特征明显,在高围压下(200,400 kPa)呈现应变硬化特性;炉渣的峰值强度与龄期增加呈现对数关系,即随着时间增长,强度逐渐增加,在早期阶段(14 d以前)强度增长迅速,随后增长速率减缓;黏聚力和内摩擦角随着龄期增加呈现不同的变化趋势,黏聚力随着龄期增加而不断变大,且近似呈现线性增长,而内摩擦角基本保持不变。研究成果可为炉渣的二次利用提供参考。     

排污河道对沿岸地下水水质的影响

为了阐明排污河道对地下水水质的影响程度和影响范围 ,以石家庄市排污河道氵交河为例 ,进行了河道污水对沿岸地下水污染机理的专题研究。通过此次研究 ,找出了污染物在地下水中的扩散规律 ,确定了河道污水对地下水环境的影响范围 ,为防污、治污提供了科学的理论依据。     

唐山市某垃圾填埋场对浅层地下水水质的影响

垃圾填埋是我国目前处理城市生活垃圾的主要方式,由此引发的垃圾填埋场渗滤液对地下水污染已成为当前主要的水环境污染.选择唐山市某垃圾填埋场为研究对象,通过对垃圾填埋场周围布孔,对地下水取样和监测,分析了垃圾填埋场对其周围地下水环境的影响.结果表明地下水中污染因子主要为COD、NH4 +-N、NO3-N、总硬度及溶解性总固体.目前该区域地下水已受到垃圾填埋场渗滤液的污染,在第四系地层保持完整而不被破坏的情况下,形成的地下水污染晕深度不超过30 m.随着垃圾填埋场运行时间的延长,垃圾渗滤液对周围浅层地下水环境的影响范围及程度还有待于进一步研究.     

城市垃圾卫生填埋场渗滤液处理综述

结合工程实际和实验研究,针对垃圾卫生填埋场技术背景及垃圾渗滤液的特点和影响因素,介绍了垃圾处理的3种方法,物化法、生物法和土地处理法,为今后的研究提出了建议。     

Entropy and Multi-Objective Based Approach for Groundwater Quality Monitoring Network Assessment and Redesign

Selection of the number and location of groundwater quality monitoring wells may require the consideration of different aspects such as: monitoring objectives, temporal frequency of monitoring, and monitoring costs. These aspects were examined using observations of groundwater quality variables made twice a year in 124 wells in the northern part of the Gaza Strip, where groundwater is of the best quality. Considering these features the groundwater quality monitoring network was assessed and redesigned using entropy. The assessment procedure was based on expressing transinformation as a function of distance between wells. It was found that the number and location of groundwater quality monitoring wells varied if these aspects were embedded in the assessment and redesign procedure.     

应用DRASTIC模型评价湛江市浅层地下水脆弱性

地下水脆弱性研究是目前国际水文地质工作的热点,而脆弱性评价是确定地下水资源保护措施是否可行的关键。该文根据湛江市的具体情况,选取地下水埋深等7个参数作为评价因子,在GIS平台上建立其基础和专题数据库,应用DRASTIC模型对湛江市浅层地下水脆弱性进行评价,编制脆弱性分区图。应用实测地下水硝酸盐浓度分布状况对评价结果进行验证,结果表明DRASTIC模型能够较好地反映湛江市浅层地下水脆弱性。     

水利工程地下水环境影响评价

拟建的四川某水库位于丘陵峡谷之中,工程区内分布侏罗系、白垩系河湖相红色砂、泥岩沉积,属于红层地区。项目建设是否会对区域地下水环境产生影响,进而导致与地下水有关的水土流失及生态破坏等环境问题值得特别关注。通过对该新建水利工程的地下水环境现状调查评价与监测,了解区域地下水环境现状,预测本工程在施工期和运营期对周围地下水环境影响的范围和程度,从环境保护角度出发论证工程建设的合理性、可行性。     

Spatio-Temporal Groundwater Vulnerability Assessment - A Coupled Remote Sensing and GIS Approach for Historical Land Cover Reconstruction

This paper presents a spatial-temporal groundwater vulnerability assessment, based on a coupled remote sensing and GIS approach for historical land cover reconstruction. This flexible methodological tool can be used for spatiotemporal vulnerability assessment in fresh water systems. The transboundary watershed of the Águeda River was used as an experimental case study where the DRASTIC and DRASTIC pesticide indices and the Susceptibility Index (SI) were used for vulnerability assessment. Land-use temporal evolution was mapped using remote sensing, taking into account the aerial frames of the historical American Flight of 1956/59, the IGN’s 1984 Flight and CORINE Land Cover (1990, 2000 and 2006) as spatial information. Four new land-use layers were considered in the SI’s temporal evolution assessment, namely for 1959, 1990, 2000 and 2006, respectively. In the last 50 years, the highest vulnerable areas to groundwater contamination have been concentrated mainly in the central zone of the watershed where the tertiary aquifer and the largest urban area are located. Future research will involve feasibility studies of different treatment schemes and the development of specific monitoring activities.     

沧州市地下水质量分析

通过对沧州市地下水资源质量分析评价,科学把握该地区地下水水资源质量条件,为有针对性地进行水资源开发、利用及有效管理提供科学技术支持.     

Sediment Yield Assessment of a Large Basin using PSIAC Approach in GIS Environment

Reservoirs are the key infrastructure for the socio-economic development of a country. The reservoirs are proven to be a remedial solution of highly erratic spatial and temporal availability of water. The growth in population and consequent developmental activities within a catchment area has shown to aggravate the problem of sedimentation which comprised of erosion, sediment transport and its deposition in these reservoirs. Among all above mentioned, reservoir sediment deposition is most important as it reduces its useful life and impairs the purposes of these vast water resource. The sediment yield has been considered as comprehensive index for assessing sustainability of such resources. The present study investigates the suitability of Pacific Southwest Inter-Agency Committee (PSIAC) model in determining the sediment yield rate for a drainage basin considering nine basin factors in geographical information system (GIS) environment. For the analysis, a large river basin at the foothill of Himalayas in India has been considered as case study. It was realized that the GIS approach made large basin characteristic sampling very easy and efficient for this hilly basin. A regression equation between specific sediment yield and effective model factors was established based on geomorphic features for this basin. It was observed that most of the basin area is falling under moderate to high sediment yielding potential zone, leading to high sediment yield.     

沧州市地下水质量分析

通过对沧州市地下水资源质量分析评价,科学把握该地区地下水水资源质量条件,为有针对性地进行水资源开发、利用及有效管理提供科学技术支持。     

大石桥市地下水环境质量评价

设地下井观测网是一个全向量的空间集合,各监测井不同的水质参数又是这个空间的连通子集,采用高斯方程拟合这个空间集合。用傅立叶级数进行子集收敛,依据地下水环境质量评价标准来进行地下水环境质量评价,取得了较好的效果。     

GIS在地质环境质量评价中的应用

地理信息系统(GIS)因其具有强大的数据处理和空间分析功能,为地质环境研究提供了新的研究方法。在阅读大量文献的基础上,讨论了地质环境质量评价的类型、方法及GIS应用于地质环境质量评价的研究进展。     

汉中市地下水水质动态变化原因分析

以2004年～2008年汉中市城区12个地下水水质监测点的监测数据为依据,根据本区地下水水质特征,选取矿化度、总硬度、硝酸盐、氟化物、有毒有害物(挥发酚C6H5OH、氰化物CN-、砷As、铬离子Cr6+、铅离子Pb2+、镉离子Cd2+、汞离子Hg2+)五项分析指标,按照国家<地下水质量标准)GB/T14848-93推荐的单因子评价法进行评价分析,得出五年间区内潜水及浅层地下水的动态变化趋势,最后提出对区内地下水污染的防治措施.     

基于ArcGIS的地下水浓度场绘制及质量评价

简述了我国北方地区近年来开展的地下水环境地质调查与评价工作,阐述了进行区域地下水浓度场绘制时需要考虑的主要因素、评价方法及基于ArcGIS的计算机实现步骤。结果表明:考虑了水文地质单元分区、地下水流向、溶解组分分布类型的评价方法更合理,结果更符合实际。以北京平原区为例,选取总硬度、总Fe含量进行了区域地下水水化学场刻画,并进行了浅层地下水的TDS单因子和综合质量评价。     

Impact of Flood Spreading on Groundwater Level Variation and Groundwater Quality in an Arid Environment

In arid and semiarid areas, bimodal and high rainfall leads to infrequent flood that can be extremely damaging. To reduce the impacts of persistent intra-seasonal drought and also to reduce flood damaging in arid and semiarid areas, rainwater storage is a prerequisite that keeps water far from evapotranspiration, increases groundwater level and decreases flood hazards modification to exchange between surface water and groundwater through flood spreading, dams, etc. The purpose of this paper is to delineate and explain variations in groundwater recharge and groundwater quality along an ephemeral stream that has been modified by flood spreading. Groundwater samples were collected from 14 deep wells located at different distances from flood spreading projection area (FSPA) in 1 month interval during September 2005 to September 2008. Groundwater quality was followed via Na⁺, K⁺, Ca²⁺, Mg²⁺, Cl^-, Hco₃^- SO₄^2-, Electrical Conductivity (EC) and pH measurements for two time periods between 2005 and 2008. The results show significant impact of flood spreading in groundwater table and groundwater salinity variation. Groundwater table decreased in all study wells, but groundwater drawdown increased by increasing the distance to FSPA (during 4 years study, 11.02 m in the well located at 20 m of FSPA versus 38.88 in the well located at 1,825 m). Also ion concentration increased in all of the wells during the study period, but the increasing ion concentration was significantly less important in FSPA closeness.     

垃圾焚烧炉渣混合土大型直剪试验研究

底渣为城市生活垃圾焚烧后的产物,具有砂性材料的性质,可作为路基的填料。为研究其抗剪性能,将其与黏土进行混合,分别在两种压实度和4种黏土含量下进行室内大型直剪试验。试验结果得到了8种底渣混合土的黏聚力和内摩擦角。试验结果表明:① 压实后的底渣具有良好的抗剪性能,随着底渣含量的增加,底渣混合土的抗剪强度增加,黏聚力下降,内摩擦角增加;② 随着压实度的增加,底渣的抗剪性能增加,黏聚力明显增加,内摩擦角有所下降。