长沙市固体废弃物处理场水文地质及环境效应评价

为了解垃圾填埋场周边地下水环境污染状况,以长沙市固体废弃物处理场周边土壤、地下水及下游水库水质为研究对象,对研究区进行采样分析,采用单因子污染指数法和内梅罗污染综合指数法对该垃圾填埋场周边环境重金属含量特征进行分析与风险评价。结果表明：As、Cr（Ⅵ）、Ni、Pb、Zn、Cu重金属是填埋场周边环境中的主要污染物,区域采样点及下游水库中重金属含量均值低于地下水质量标准Ⅲ类,填埋场区污染状况良好;Cr（Ⅵ）含量在ZK1与R1样品中均高于地下水质量标准Ⅲ类,是填埋场周边地下水的主要风险污染物;ZK1~ZK4中土壤重金属元素以Pb、Cr（Ⅵ）富集为主,其达中度污染程度,应引起重视。     

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。     

贵阳市简易垃圾填埋场与卫生垃圾填埋场污染对比研究

<正>对贵阳市6个简易垃圾填埋场和一个卫生垃圾填埋场(比例坝垃圾填埋场)的岩石、土壤、地下水中的污染物的污染特征进行了对比研究,另外还采集了浪风关垃圾填埋场、望城坡垃圾填埋场的植物样品(水稻)以及望城坡垃圾填埋场的煤渣样品进行研究。结果显示:1)本次研究所涉及的垃圾填埋场中,岩石、土壤、水等介质中均有不同程度的污染。在岩石浸出液中污染指标主要有TP、TK、Zn、Mn、As、CODMn、NO-3、SO2-4等;土壤浸出液及原样中污染指标主     

基于modflow对某简易垃圾填埋场地下水污染预测研究

垃圾填埋技术是我国应用较广的垃圾处理技术,以某简易垃圾填埋场为例,查明研究区水文地质条件,通过计算得到垃圾渗漏液产生量及相关污染物浓度,选取合理预测参数,运用visual-modflow软件建立研究区地下水流场及地下水溶质运移模型,对研究区地下水相关污染因子进行预测,根据相关预测模型和参数,结果发现:该简易垃圾填埋场中氨氮污染距离可达536.4 m;高锰酸钾指数污染距离可达480.36 m,说明该简易垃圾填埋场渗滤液的泄漏已对下游一定区域的地下水环境造成了污染。     

阜新城市垃圾填埋场对地下水污染的研究

随着我国城市化的发展,城市生活垃圾产量剧增,垃圾渗滤液对地下水的污染问题已成为当前主要的水环境污染问题。通过对阜新市城市垃圾填埋场地理、地质和气候特征的调查,结合阜新市城市发展现状,分析了阜新市城市垃圾填埋场垃圾成分,渗滤液产生量及渗滤液中污染物的浓度,得出了阜新市城市垃圾填埋场渗滤液中各种污染物污染地下水的源强度。采用数值模拟的方法,对垃圾渗滤液污染地下水的情况进行模拟分析,验证了模拟方法的正确性,并对今后的污染情况进行了预测分析。     

河北省垃圾填埋场对地下水的污染分析

从河北省垃圾场的调查情况来看,全省处理生活垃圾的主要方式为垃圾填埋,且垃圾填埋场以未采取任何防渗措施的简易填埋场为主,约占垃圾场总数量的三分之二,已对环境造成一定污染。本文分析了河北省生活垃圾及其渗沥液化学成分,确定了生活垃圾及其渗沥液的主要污染成分。采用污染指数法,分析研究了河北省18个生活垃圾填埋场对地下水的污染情况,并总结出了垃圾填埋场对地下水的污染规律,对垃圾填埋场的建设和水资源的保护具有指导意义。     

垃圾填埋场渗滤液及对地下水污染研究进展

在查阅国内外相关文献的基础上,综述了垃圾填埋场渗滤液的产生、危害、污染特性、产生量和影响因素以及为防止地下水污染而采取的防渗措施,并系统阐述了国内外渗滤液污染物在地下水中迁移转化研究取得的成果和垃圾生态填埋技术研究现状,指出了我国填埋场目前研究中存在的主要问题和未来在该领域需重点研究的课题和一些新思路。     

北京地区垃圾填埋对地下水的污染及垃圾填埋场选址分区

本文介绍了北京市生活垃圾处理现状及由于垃圾填埋而引起的地下水污染问题。以北京西郊南部北天堂垃圾填埋场的污染状况为例进行研究,通过建立数学模型来模拟污染物在地下水中的运移及补救效果,对污染控制进行了模拟,分析及提出相关建议;并对北京市生活垃级填埋场遗址进行了分区。     

不同龄期垃圾渗滤液对浅层地下水污染的实验研究

为了深入了解垃圾渗滤液对浅层地下水污染的机理,揭示不同龄期垃圾渗滤液在浅层地下水中多组分运移规律,文章以阜新市垃圾填埋场为研究对象,通过室内土柱对比实验,研究了不同龄期垃圾渗滤液在浅层地下水中多组分运移的机理和规律。结果表明不同龄期垃圾渗滤液在入渗过程中都会引起地下水不同程度的污染,且新鲜垃圾渗滤液较老龄垃圾渗滤液更易污染地下水,其污染机理主要为吸附、解析、溶解、沉淀和离子交换等水岩作用。研究结果为今后垃圾填埋场的治理和地下水的修复提供理论依据。     

兰考县水土污染现状及防治对策探析

兰考县位于河南省东部,近年来随着城市工业、乡镇企业的发展,城市垃圾堆放量及污水排放量不断增加。由于处于黄河下游冲积平原区,地表防护性能较差,地下水及土壤遭到一定程度污染。本文对兰考县的地下水及土壤的污染现状进行了评价,提出了水土污染防治对策,可为兰考县水土污染防治提供科学依据。地下水污染现状评价,采用单项组份评价和综合评价,单项组份评价按照水分析成果与地下水质量标准比较,综合评价在单项评价的基础上根据内梅罗公式按综合指数进行评价。工作区地下水多为未污染,未污染水质分布于全区大部分区域,仅在局部检测部分单因子超标,造成轻微污染。土壤污染评价按土壤环境质量标准值计算单指标土壤环境质量指数,单一元素土壤污染指数得出后,然后按内梅罗法计算综合污染指数。一级质量区主要分布在城市建成区周围及西部大部分区域。二级质量区主要分布在局部区域。水土污染防治对策：(1)从源头控制污染物的排放量;(2)做好污染物堆放场地的防渗工作;(3)加强污染场地水质监测,严防污染事故发生。     

北京市北天堂生活垃圾场地的地质环境效应评价

通过对生活垃圾主要污染成分分析，选出污染评价因子；采用单因子和多因子评价法对垃圾场地周围的地下水和土壤进行污染程度评价；为防止地下水及土壤的污染，认为生活垃圾严禁随意堆放，选择垃圾场址时必须进行环境影响评价。     

北京北天堂地区城市垃圾填埋对地下水的污染

本文介绍了由于城市垃圾填埋而引起的地下水资源污染问题，以北京南部北天堂垃圾填埋场的污染状况为例进行调查，对其进行污染综合评价，通过建立数学模型模拟污染物在几种条件下的地下运移情况补救效果，对污染控制进行了模拟、分析及提出相关的控制与治理的建议及措施。     

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.      

Aquifer vulnerability assessment using the DRASTIC model at Russeifa landfill,northeast Jordan

Groundwater is inherently susceptible to contamination from anthropogenic activities and remediation is very difficult and expensive. Prevention of contamination is hence critical in effective groundwater management. In this paper an attempt has been made to assess aquifer vulnerability at the Russeifa solid waste landfill. This disposal site is placed at the most important aquifer in Jordan, which is known as Amman-Wadi Sir (B2/A7). The daily-generated leachate within the landfill is about 160 m³/day and there is no system for collecting and treating this leachate. Therefore, the leachate infiltrates to groundwater and degrades the quality of the groundwater. The area is strongly vulnerable to pollution due to the presence of intensive agricultural activity, the solid waste disposal site and industries. Increasing groundwater demand makes the protection of the aquifer from pollution crucial. Physical and hydrogeological characteristics make the aquifer susceptible to pollution. The vulnerability of groundwater to contamination in the study area was quantified using the DRASTIC model. The DRASTIC model uses the following seven parameters: depth to water, recharge, aquifer media, soil media, topography, impact on vadose zone and hydraulic conductivity. The water level data were measured in the observation wells within the disposal site. The recharge is derived based on precipitation, land use and soil characteristics. The aquifer media was obtained from a geological map of the area. The topography is obtained from the Natural Resources Authority of Jordan, 1:50,000 scale topographic map. The impact on the vadose zone is defined by the soil permeability and depth to water. The hydraulic conductivity was obtained from the field pumping tests. The calculated DRASTIC index number indicates a moderate pollution potential for the study area.     

Site investigation on heavy metals contaminated ground in Estarreja — Portugal

Owing to its five decades in the chemical industry, Estarreja is one of the most important industrial areas in Portugal. Intensive industrial activity along with both direct discharge of the effluents into natural water streams and uncontrolled waste disposal on the ground has, throughout the years, had strong impact on health and welfare. Recently an association between industry and local authorities was created — ERASE. The main goal for this association is to find, in co-operation with the Portuguese Environmental Ministry, a cost-effective solution to deal with the soil/sediments contamination and solid waste problem.

The ERASE association planned to build a landfill for both solid waste and contaminated soil/sediments disposal. In order to determine more accurately the volume of material to be disposed of in the landfill, a site investigation was carried out during September/November 1998. The site investigation consisted mainly of systematic soil sampling at shallow depths, both within the industrial area and along the natural water streams.

The site investigation results revealed high concentrations of toxic pollutants, mainly heavy metals (namely As, Hg, Pb and Zn), in the soil of the industrial area. Much higher concentrations were found in the sediments of the water streams, several kilometres away from the industrial complex (the pollution source area).

In most cases, concentration increases with depth, reaching groundwater. Therefore the site investigation programme carried out could not determine the full extent of the contamination. Consequently, further studies were strongly recommended, which should include a wider and deeper investigation area and groundwater sampling.     

柔性垂直阻隔技术在危废污染应急治理项目中的应用

通过江苏省靖江市一危废污染应急治理项目,对比刚性垂直阻隔,采用柔性垂直阻隔可更好地阻断场地内填埋污染物与周边土壤及地下水的水力联系。柔性垂直阻隔具有防渗性能好、抗变形能力强、使用寿命长等特点,并重点阐述了其技术原理、施工工艺及施工要点,可为后续类似工程提供参考。     

垃圾渗滤液在含水层中的污染规律研究——以阜新市垃圾填埋场为例

垃圾的堆存和填埋会产生大量的渗滤液。渗滤液对垃圾填埋场周围环境能够造成严重污染,尤其使地下水质污染而丧失利用价值。通过阜新市垃圾填埋场现场采集新鲜渗滤液水样、垃圾堆体附近土样的实验研究,获得了新鲜渗滤液的各组分浓度和垃圾堆体附近土壤的性质。结合当地地理气候等情况揭示了垃圾渗滤液中污染溶质在地下水系统中的迁移转化的动态过程,定量化预测了污染范围及时空分布,为研究该地区地下水污染控制、管理和评价提供了可靠依据。     

Containment landfills: the myth of sustainability

A number of major problems associated with the containment approach to landfill management are highlighted. The fundamental flaw in the strategy is that dry entombment of waste inhibits its degradation, so prolonging the activity of the waste and delaying, possibly for several decades, its stabilisation to an inert state. This, coupled with uncertainties as to the long-term durability of synthetic lining systems, increases the potential, for liner failure at some stage in the future whilst the waste is still active, leading to groundwater pollution by landfill leachate. Clay liners also pose problems as the smectite components of bentonite liners are subject to chemical interaction with landfill leachate, leading to a reduction in their swelling capacity and increase in hydraulic conductivity. Thus, their ability to perform a containment role diminishes with time. More critically, if diffusion rather than advection is the dominant contaminant migration mechanism, then no liner will be completely impermeable to pollutants and the containment strategy becomes untenable.

There are other less obvious problems with the containment strategy. One is the tendency to place total reliance on artificial lining systems and pay little attention to local geological/hydrogeological conditions during selection of landfill sites. Based on the attitude that any site can be engineered for landfilling and that complete protection of groundwater can be effected by lining systems, negative geological characteristics of sites are being ignored. Furthermore, excessive costs in construction and operation of containment landfills necessitate that they are large scale operations (superdumps), with associated transfer facilities and transport costs, all of which add to overall waste management costs. Taken together with unpredictable post-closure maintenance and monitoring costs, possibly over several decades, the economics of the containment strategy becomes unsustainable. Such a high-cost, high-technology approach to landfill leachate management is generally beyond the financial and technological resources of the less wealthy nations, and places severe burdens on their economies. For instance, in third world countries with limited water resources, the need to preserve groundwater quality is paramount, so expensive containment strategies are adopted in the belief that they offer greatest protection to groundwater. A final indictment of the containment strategy is that in delaying degradation of waste, the present generations waste problems will be left for future generations to deal with.

More cost-effective landfill management strategies take advantage of the natural hydrogeological characteristics and attenuation properties of the subsurface. The ‘dilute and disperse’ strategy employs the natural sorption and ion exchange properties of clay minerals, and it has been shown that in appropriate situations it is effective in attenuating landfill leachate and preventing pollution of water resources. Operated at sites with thick clay overburden sequences, using a permeable cap to maximise rainfall infiltration and a leachate collection system to control leachate migration, ‘dilute and disperse’ is a viable leachate management strategy. Hydraulic traps are relatively common hydrogeological situations where groundwater flow is towards the landfill, so effectively suppressing outwards advective flow of leachate. This approach is also best employed with a clay liner, taking advantage of the attenuation properties of clays to combat diffusive flow of contaminants. These strategies are likely to guarantee greater protection of groundwater in the long term.