北京市地下水污染源荷载影响评价

在阐述地下水污染源荷载影响基本概念的基础上,介绍了污染源荷载影响评价的3大要素:污染荷载等级、含水层敏感性及地下水价值,说明了评价体系、指标和方法及过程。根据主要污染源荷载分析,结合地下水环境现状,对北京市进行了分区,提出污染源管理措施。     

下辽河平原地下水健康风险评价

通过在下辽河平原布设217个地下水采样点,调查监测其中典型的无机、有机化合物,并应用美国EPA健康风险评价模型进行风险评价。结果表明:该区域地下水中无机化合物较有机化合物浓度水平高;无机化合物中NO_3~-、NO_2~-、Mn及As浓度较高,有机化合物中γ-六六六浓度较高。所有监测的无机、有机化合物通过饮用水途径引起的致癌风险高于非致癌风险;所有化合物的非致癌风险数值均小于ICRP推荐的最大可接受风险水平10~(-6)a~(-1),As致癌风险最大值为6.15×10~(-5)a~(-1),超过EPA推荐的可接受值5.0×10~(-5)a~(-1)。     

重庆典型岩溶地区地下水多环芳烃污染水平及健康风险

采集重庆3个典型岩溶地区113个地下水样品,利用人体暴露风险系数法对16种优先控制多环芳烃(PAHs)饮水途径健康风险进行评价。结果表明:地下水中PAHs、致癌PAH和BaP的质量浓度分别为200 ng/L～2 638 ng/L、未检出～362 ng/L和未检出～62.7 ng/L,其中南川区地下水中BaP质量浓度为45.1 ng/L,已超过《生活饮用水卫生标准》(GB 5749—2006)的水质要求。PAHs污染水平为南川区老龙洞流域青木关流域,与国内其他岩溶地区地下水相比,处于较高污染水平。人群的致癌风险(ILCR)为5×10~(-10)～2.80×10~(-5),其中南川区ILCR10~(-6),具有潜在致癌风险;非致癌类PAHs饮水途径健康风险处于10~(-11)～10~(-9)水平,远低于USEPA规定的阈值1。     

地下水评价的污染损失率法

应用污染损失率法对地下水进行了质量评价,评价结果物理意义明确,实例分析表明了该法结果与模糊综合学评判学,物元分析法和灰色理论模型法的评介结果一致。     

乌鲁木齐河流域浅层地下水防污性能评价

地下水防污性能的评价是确定地下水资源保护措施是否可行的关键。本文根据乌鲁木齐河流域浅层地下水水文地质状况,采用DRASTIC模型,选取包气带岩性、厚度与结构、地形作为评价因子,在乌鲁木齐河流域地下水污染现状评价的基础上,用模糊综合评判法评价了地下水防污性能,从而为乌鲁木齐河流域地下水污染防治提供了依据。     

污染因子相关分析判定地下水污染源

把相关分析用于地下水污染源的判定,在安阳市劳教所一带地下水污染事故中成功地判定了污染源     

垃圾填埋场地下水污染对居民健康的风险评价

调查了某垃圾填埋场地下水和周边居民饮用水中的As、Hg等重金属和挥发酚等有机物的污染状况,运用美国环保局的健康风险计算模型,评估了该垃圾填埋场地下水对周边居民的潜在健康风险。结果表明,各类人群对4种有阈化合物的饮食和皮肤暴露的终身健康危险度在8．2×10^-11～1．3×10^-10之间,均低于可以接受的风险水平10^-6;对As的终身超额健康危险度在3．1×10^-7～4．9×10^-7之间,表明地下水中砷污染对居民潜在的致癌风险不明显。各类人群通过皮肤对Hg、As、Cd和挥发酚的暴露剂量比通过饮水暴露的剂量高0．7倍～14．5倍,皮肤暴露将是地下水影响人体健康并构成潜在风险的重要途径。     

南宁市河流型水源地重金属污染调查与健康风险评价

通过对南宁市河流型水源地水体中Pb、Cd、Hg、As浓度调查与健康风险评价研究,结果表明:这4种元素在水体中的质量浓度较低,均达到《地表水环境质量标准》(GB 3838-2002)Ⅱ类标准;经饮水途径引起的健康风险从大到小依次为AsCdPbHg,说明As是南宁市饮用水源中的主要风险因子;4种元素通过饮水途径引起的平均个人年健康致癌风险值为1.48×10-6a-1~13.75×10-6a-1,非致癌风险值为7.05×10-10a-1,均低于美国环保局和国际辐射防护委员会的推荐值。     

长三角地区饮用水水源地典型重金属污染状况及环境风险评估

随着城镇化和工业化的快速发展,长江三角洲地区饮用水水源水质安全引起了社会普遍关注。其中,重金属污染是该地区饮用水安全和水生态健康的重要隐患。因此,选取长三角地区107个县级以上集中式生活饮用水水源地为研究对象,分析该地区2017—2022年6种重金属(铜、锌、铅、砷、汞、镉)的总体污染状况和时空分布特征,并开展人体健康风险和生态风险评估。结果表明:长三角地区水源地水质总体良好,6种重金属污染程度总体较低。砷、铜、锌在河流型水源地中的浓度水平均高于湖库型水源地,而镉、汞、铅在湖库型水源地则相对更高,水源地重金属浓度水平受季节变化影响不大。砷、汞的生态风险较低,锌、铅、镉处于中低风险水平,铜主要处于中风险水平,但是每年均有部分水源地出现高风险。铜、锌、铅、汞、镉不会对人体产生非致癌健康风险,但是砷可能产生潜在的非致癌风险。砷、铅的致癌风险指数为10^-6~10^-4,可能具有潜在致癌风险。镉与污水排放有一定的相关性,砷的来源可能主要与自然地质等因素有关。综上,长三角地区饮用水水源地重金属污染环境风险管理的主要对象是铜、砷、铅。     

某废弃农药生产场地地下水挥发性有机物污染健康风险评价

对常州某废弃农药生产场地地下水中挥发性有机物污染状况和健康风险进行了调查评价。结果表明,该场地地下水中挥发性有机物污染以苯系物、氯代苯类和氯代烃类为主;部分点位地下水健康风险评价结果超出可接受范围,可能危害人体。     

Techniques of remote sensing applied to the environmental analysis of part of an aquifer located in the São José dos Campos Region sp,Brazil

The anthropogenic activity on the surface can modify and introduce new mechanisms of recharging the groundwatersystem, modifying the tax, the frequency and the quality ofrecharge of underground waters. The understanding of thesemechanisms and the correct evaluation of such modifications arefundamental in determining the vulnerability of groundwatercontamination. The groundwater flow of the South ParaíbaCompartment, in the region of São José dos Campos, São Paulo, is directly related to structural features of theTaubaté Basin and, therefore, the analysis of its behaviourenhances the understanding of tectonic structure. The methodologyadopted for this work consists in pre-processing and processing of the satellite images, visual interpretation of HSI products, field work and data integration. The derivation of the main structural features was based on visual analysis of the textureelements of drainage, and the relief in sedimentary and crystalline rocks. Statistical analysis of the feature densitiesand the metric-geometric relations between the analysed elementshave been conducted. The crystalline rocks, on which the sediments were laying, conditions and controls the structural arrangement of sedimentary formations. The formation of the SouthParaíba Grabén is associated with Cenozoic distensive movement which reactivated old features of crust weakness and generated previous cycles with normal characteristics. The environmental analysis is based on the integration of the existing methodology to characterise vulnerability of an universal pollutant and density fracture zone. The digital integration was processed using GIS (Geographic Information System) to delineate five defined vulnerability classes. The hydrogeological settings were analysed in each thematic map and,using fuzzy logic, an index for each different vulnerability class was compiled. Evidence maps could be combined in a seriesof steps using map algebra.     

Leachate Characterization and Assessment of Groundwater Pollution Near Municipal Solid Waste Landfill Site

Leachate and groundwater samples were collected from Gazipur landfill-site and its adjacent area to study the possible impact of leachate percolation on groundwater quality. Concentration of various physico-chemical parameters including heavy metal (Cd, Cr, Cu, Fe, Ni, Pb and Zn) and microbiological parameters (total coliform (TC) and faecal coliform (FC)) were determined in groundwater and leachate samples. The moderately high concentrations of Cl⁻, NO⁻ ₃, SO²⁻ ₄, NH⁺ ₄, Phenol, Fe, Zn and COD in groundwater, likely indicate that groundwater quality is being significantly affected by leachate percolation. Further they proved to be as tracers for groundwater contamination. The effect of depth and distance of the well from the pollution source was also investigated. The presence of TC and FC in groundwater warns for the groundwater quality and thus renders the associated aquifer unreliable for domestic water supply and other uses. Although some remedial measures are suggested to reduce further groundwater contamination via leachate percolation, the present study demand for the proper management of waste in Delhi.     

occurrence and distribution of nitrate and pesticides in bowdle aquifer, south dakota

A shallow aquifer in central South Dakota was monitored for thepresence of nitrate and pesticides. A total of 593 nitrate samples and428 pesticide samples were analyzed from nine different sites and 14wells between 1989 and 1994. Nested wells were installed at four sitesto characterize the distribution pattern of nitrate and pesticidemovement in ground water. Nitrate concentrations and pesticidedetections were qualitatively compared with area precipitation and watertable fluctuations. The results indicate that nitrates tend to betransported by a leaching mechanism in a matrix flow and may appearin ground water within months after the fertilizer application in thefields. The pesticide movement is primarily controlled by geologicaland chemical characteristics of medium and pesticides.     

Dense Nonaqueous Phase Liquid Tracer Tests: Experimental Results

Two dense nonaqueous phase liquid (DNAPL) tracer tests werecarried out in a shallow aquifer north of Fort Worth, TX. i-Propanolwas used as the nonpartitioning tracer; n-hexanol and n-octanol werethe partitioning tracers. Field data, mathematical modeling, theresults of column tests, and field tracer tests with NaCl were usedin designing the DNAPL tracer tests. The results indicated the presenceof DNAPL at both sites tested; semi-quantitative estimates of theamounts of DNAPL present were obtained by mathematical modeling.Interpretation was complicated by heterogeneity of the aquifer andmass transport effects.     

化工开发区突发性大气污染事故预测预警系统建设架构

大气污染事故预测预警系统主要包括污染气象模型和大气扩散数学模型,利用地理信息系统(GIS)技术,按照污染事故发生的地理位置,将模型的数值解和GIS相结合,从而可以在时间和空间上对污染扩散进行分析,得到不同地点的污染物浓度和污染程度,获取受污染范围内的人口和周边单位等重要信息,从而预测污染事故对环境的影响程度和范围,为突发性环境污染事故的应急监测、现场救护和灾后评估提供科学依据。     

江苏某县地下水邻苯二甲酸酯类的检测与风险评价

在江苏某癌症高发区对地下水进行布点,采用固相萃取与气相色谱-质谱联用方法测定深层地下水和浅层地下水中邻苯二甲酸酯类(PAEs)的浓度。检测结果表明,地下水中PAEs污染程度较严重,邻苯二甲酸二丁酯(DBP)和邻苯二甲酸二(2-乙基己基)酯(DEHP)均有超标现象,其中,丰水期深层地下水和枯水期浅层地下水中DBP超标率达到100%,最大超标10.7倍。PAEs总质量浓度均值为10 034.56~14 872.91 ng/L,丰水期总浓度均值大于枯水期,浅层地下水的总浓度均值大于深层地下水。采用优化的USEPA风险评价模型,对PAEs进行人体健康风险评价,评价结果表明,该地区52.5% 地下水的PAEs总致癌风险超过10^-6的水质监控值,总非致癌风险在可接受范围内。     

Assessment of Ground Water Vulnerability and its Application to the Development of Protection Strategy for the Water Supply Aquifer in Owerri, Southeastern Nigeria

Pollution vulnerability of theOwerri regional water supply aquifer wasevaluated as a basis for developing appropriateprotection strategy for the groundwaterresource. The assessment was accomplished usingLegrand, GOD, Siga and DRASTIC models.Techniques of the models generally involvedparameters rating and point count systems, whichare based on the evaluation of various parameterin relation to their capacity for enhancing orattenuating contaminants in the groundwatersystem. Field and laboratory evaluations of theparameters indicate that the Owerri areagenerally occupies a nearly, flat topographywith a relatively high groundwater recharge. Thearea is underlain by predominantly sandyfacies in the Northern area which grades intogravelly sequences towards the southwest. TheSoutheastern area is distinguished by thickclayey facies that thin westwards towards theOwerri metropolis. Effective hydraulicconductivity (Kz) in the downward directionranges from 1.44 × 10^-3 to 5.6 × 10^-9 m s^-1; with the upper limits reflecting coarsesands and gravelly units. The amount of clay andclay-size particles in the sandy and gravellyunits is negligible, suggesting that thesorptive capacity of the units is low. Depth towater table decreases southwards while hydraulichead gradients vary between 0.09 and 0.22.Groundwater occurs in unconfined conditions inmost places except in the southeastern zonewhere it is semi-confined due to the presence ofa clayey unit. The groundwater vulnerabilitymap developed on the basis of the models andseveral other thematic maps shows that theOwerri metropolis and the southwest area ofOwerri have high vulnerability, indicatinggroundwater pollution. The existing wastedisposal sites in these sub-areas should beabandoned and rehabilitated to forstall furtherpollution of the groundwater system. Areas tothe North and Southeast of Owerri have moderateand low vulnerabilities, respectively,indicating the relatively lower sensitivity ofthe groundwater system in the sub-areas tocontamination. The lower sensitivity couldfurther be matched with properly engineeredsanitary landfills in the event of choice ofsites, as an additional protective strategy forthe groundwater system.     

论水污染物排放统计指标体系

水污染物排放统计指标体系包括水污染物排放统计指标以及排放管理指标,统计对象主要是规模以上点源。实施统计的污染源的规模应当是全国统一的。统计指标区分为指标、主要参数和辅助参数,既便于理解也便于管理;将排放指标细化为污染源排放量、入河排放量和通量使得排放概念更加清晰,有利于水环境管理。对入河排放量和污染源排放量的比较,可以确定纳入统计范围的污染源的代表性,对通量和入河排放量的比较可以推断非点源污染物排放状况。以流域为单元的,以通量、入河排放量和污染源排放量为主要概念的排放统计管理方式,有助于提高流域水污染防治的确定性和一致性。     

城市区域水污染物排放核查方法与案例研究

城市水污染物排放信息是城市水环境保护决策和管理的依据,但城市水污染控制的外部性使城市水污染物排放信息产生失真风险,需要对城市区域水污染物排放信息核查。通过高质量数据对低质量数据的核查,用基于监测的水污染物入河量数据核查基于环境统计申报与排污系数的水污染物入河量数据,完善了城市区域水污染物排放核查方法。案例分析结果显示,环境统计COD入河排放量明显偏小。建议水污染物排放统计以入河量为核心,建立入河排污口监测体系,编制核查技术规范,实施区域污染物排放核查。     

A probabilistic methodology to assess the risk of groundwater quality degradation

An approach to assess the risk of groundwater quality degradation with regard to fixed standards, based on DisjunctiveKriging (DK) is presented. The DK allows one to evaluate the Conditional Probability (CP) of overriding a given threshold of concentration of a pollutant at a given time, and at a generic point in a consideredgroundwater system. The result of such investigation over the considered area can be plotted in form of maps of spatial risk. By repeating this analysis at different times, severalspatial riskmaps will be produced, one for each consideredtime. By means of non-parametric statistics, the temporal trendof the CPs can be evaluated at every point of the considered area. The trend index, assessed by means of a sort of classification of the trend values obtained as described above,can be superimposed on the most recent values of the spatialrisk (i.e.: the most recent values of probability). Consequentlya classification of the risk of groundwater quality degradationresults with which to weigh both the spatial distribution and thetemporal behaviour of the probability to exceed a given standardthreshold. The methodology has been applied to values of nitrateconcentration sampled in the monitoring well network of theModena plain, northern Italy. This area is characterised by intensive agricultural exploitation and hog breeding along withindustrial and civil developments. The influence of agriculture on groundwater results in a high nitrate pollution that limitsits use for potable purposes.