某危险废物安全填埋场的设计与工艺

通过某危险废物安全填埋场项目,介绍了安全填埋工程的总体设计工艺,包括危险废物填埋处置总体流程、预处理系统、填埋库体结构、防渗系统、终场覆盖及环境监测等。结合工程设计实践,探讨了危险废物填埋场设计工艺要点。分析认为在沿海软土地区,采用双衬层水平防渗和垂直防渗相结合的半刚性结构方式,可以达到有效保护库区环境的目的。     

Environmental impact and vulnerability of the surface and ground water system from municipal solid waste disposal site: Koshe, Addis Ababa

Geo-environmental assessment and geophysical investigations were carried out over the only functional municipal solid waste disposal site of the city of Addis Ababa, Ethiopia, known locally as Koshe. The accumulated wastes from Koshe have impact on the surrounding human and physical environment since the disposal site was not designed. The study deserves emphasis because the city of Addis Ababa currently obtains a considerable portion of its domestic water supply from a well field developed not much farther from and along a groundwater flow direction in relation to the waste disposal site. It was found out that the leachates from the site contain high concentration of biological oxygen demand, chemical oxygen demand, chloride and sulphate besides high concentration of cobalt, nickel and zinc in the surrounding soils. The geophysical results have mapped weak zones and near-vertical discontinuities that could potentially be conduits for the leachate from the wastes into the deep groundwater system. Further, a zone of potential leachate migration from the landfill was identified from the electrical models; the location of this zone is consistent with the predicted direction of groundwater flow across the site. The results further suggested that the open dump site tends to cause increasing amount of pollution on the surrounding soil, surface and ground waters. Furthermore, it was observed that the Koshe waste disposal site has grown beyond its capacity and the poor management of the open dump landfill has reduced the aesthetic value of the surrounding environments. The need to change/relocate the existing waste disposal site to a more suitable and technologically appropriate site is emphasized.     

Landfill site selection and landfill liner design for Ankara, Turkey

Considering the high population growth rate of Ankara, it is inevitable that landfill(s) will be required in the area in the near future to sustain the sanitary waste disposal needs of the city. The main scope of this study is to select alternative landfill sites for Ankara based on the growing trends of Ankara toward the northwest, particularly toward the Sincan municipality, and to eventually select the best alternative through utilizing multi-criteria decision making. Landfill site selection was carried out utilizing Geographic Information System (GIS) and Multi-Criteria Decision Analysis. A number of criteria, namely, settlement, slope, proximity to roads, geology, availability and proximity of landfill containment material (i.e., clay for composite lining system), suitability for agriculture, erosion, vegetation cover and lineament system were gathered in a GIS environment. Each criterion was assigned a weight value by applying the Pairwise Comparison Method and the Analytical Hierarchy Method. In order to choose the best alternative, the Technique for Order Preference by Similarity to the Ideal Solution, which is regarded as an ideal point method, was applied and a landfill site was selected. The geotechnical properties of the so-called “Ankara clay” that shows widespread distribution in Ankara were reviewed and assessed for its suitability as a compacted clay liner.     

城市垃圾性质及其填埋场的工程地质评价

卫生填埋是现阶段处理城市垃圾的主要方法,正确评价,选择填埋垃圾的工程性质对填埋场的设计极为重要;填埋场是一个综合性污染源,若处理不当,会产生严重的环境工程地质问题,做好填埋场的工程地质研究,对于水资源及环境保护具有重要意义,本文对城市垃圾的工程性质进行了分析,评价,从环境工程地质学的角度对合肥市清溪路垃圾埋场的地基勘察,主要工程地质问题及应采取的工程措施进行了探讨。     

Landfill site selection using combination of fuzzy logic and multi-attribute decision-making approach

During the last decades, growth of urbanization and industrialization led to an increase in solid waste generation. Landfilling is the most prevalent ultimate disposal method for the municipal solid wastes in developing countries. The rapid municipal solid waste generation in Markazi province (central part of Iran) causes the need for precision in finding a suitable landfill site selection. In the present study, 12 factors (environmental and socioeconomic factors) have been applied to select the landfill site in Markazi province, Iran. The different methods including the analytic network process (ANP) combined with fuzzy linguistic quantifier, ordered weighted average (OWA), and weighted linear combination (WLC) approach in geographic information system was applied to find an appropriate landfill site. The OWA operator function permits the evaluation of the wide spectrum of consequences (with different scenario) obtained from different management strategies. Results revealed that integration of fuzzy logic, ANP, and OWA provides flexible and better ideas compared to the Boolean logic and WLC to select a suitable landfill site.     

Behavior of a municipal landfill from field measurement data during a waste-disposal period

The behavior of a municipal waste landfill on marine clay was analyzed from field measurement data. Instruments, e.g., a groundwater level sensor, piezometer, earth pressure gauge, settlement plates, inclinometer, etc., were installed and operated during the disposal period from October 1992 to November 2000. A database system was developed to manage the data from this landfill using Access (Microsoft) with Delphi programs. From the analyses, it was determined that the settlement of the landfill during the initial period of waste disposal was small because of the high leachate level in the landfill. As the level of waste became higher than the leachate level, the settlement of the landfill increased significantly due to the increasing effective pressure within the landfill. From a stability point of view, the critical time for the landfill in this study was the initial period of landfill disposal, which was caused by either the impact load of waste disposal or the time schedule of waste disposal, which was faster than the consolidation of foundation clay caused by the waste load.     

北京砂石坑回填物对地下水水质影响分析

本文介绍了北京砂石坑回填现状,分析了回填物的污染组分特征。以北天堂生活垃圾填埋场和老山建筑垃圾填埋场为例,分析了生活垃圾和建筑垃圾对地下水的影响程度。结合回填物的特点,提出相应的处理对策。针对已造成地下水污染的回填地区,提出科学的污染控制和治理方法。     

A comparative study of waste landfill disposal in different countries

This study draws attention to the fact that natural processes can mobilize thallium （Tl）, a highly toxic metal, which may enter the food chain with severe health impacts on the local human population. A rural area having independent Tl mineralization in southwestern Guizhou, China, was chosen for a pilot study. Tl contents of soils extracted by HNO3 in the study area range from 35-165 mg/kg in soils from the mining area, 14-78 mg/kg in alluvial deposits downstream, and 〈0.2-0.5 mg/kg in soils from the background area. Tl contents in ammonium acetate EDTA-extracted fraction are 0.013-1.3 mg/kg, less than 1% of concentration in HNO3-extracted fraction. The amounts of Tl in NH4Ac-extracted fraction were thought to be more exchangeable and bioavailable, i.e., immediately available to plants and/or available to plant roots over a period of years. Tl concentration in crops exhibits species-dependent preferences. The enrichment of Tl in edible crop species decreases in the following order： green cabbage〉chili〉Chinese cabbage〉rice〉com. The highest level of Tl in green cabbage is up to 500 mg/kg （DW）, surpassing the values of Tl in the soils （13-59 mg/kg）. The enrichment factor for TI in green cabbage is up to 1-10 when considering the HNO3-extracted Tl, but the factor highly rises to 30-1300 while considering the NH4Ac-extracted Tl. The average daily uptake of Tl by the local villagers through consumption of locally planted crops was estimated at about 1.9 mg per person, which is 50 times the daily ingestion from the Tl-free background area.     

Safety concept and criteria for hazardous waste sites

The problem of waste disposal in Germany has been solved by using a combination of above-ground and underground disposal. Site selection criteria and precise criteria for the performance assessment of various types of waste disposal are available. In view of long-term safety of disposal, it is necessary to include geological and hydrogeological viewpoints in addition to purely engineering viewpoints.

In particular, the geotechnical site-specific safety assessment is described, as defined by the government in “Technical Regulations on Wastes” (TA-Abfall) in the section “Underground Disposal”. This safety assessment must cover the entire system comprising waste, cavern/mine and surrounding rock. For this purpose geo-mechanical models have to be developed.

According to the multi-barrier principle, the geological setting must be able to contribute significantly to isolation of the waste over longer periods. The assessment of the integrity of the geological barrier can only be performed by making calculations with validated geomechanical models.

Various engineering geological data are required for the selection of a site, for the design and construction of a repository, and for a safety analysis for the post-operational phase. These data can only be attained by the execution of a comprehensive site-specific geomechanical exploration and investigation program. The planning and design of an underground repository in rock salt layers are described, as an example for the various steps of this type of safety assessment.     

上海某生活垃圾填埋场对浅层地下水水质的影响

垃圾填埋是目前处理城市生活垃圾普遍使用的方式,由此产生的垃圾渗滤液成为主要的地下水污染源.本文以上海市某生活垃圾填埋场作为研究对象,研究垃圾填埋对地下水的影响.通过监测该场地垃圾填埋前后2年内场区及周边地下水水质的变化情况,以垃圾填埋前调查区的地下水样品分析结果为本底值,采用本底法对地下水水质进行评价来判定地下水是否受到垃圾渗滤液的影响.评价结果显示,对于本研究的水质动态监测阶段,调查区内的浅层地下水水质暂未受到垃圾渗滤液的影响,个别监测井水质发生较大变化是由于填埋场施工建设过程中,破坏了监测井井盖及挖穿了井边含水层顶层.随着整个垃圾填埋场运行时间的延长,防渗漏措施的有效性以及垃圾渗滤液对周边地下水的影响还需要进一步研究.     

生活垃圾卫生填埋及地质环境效应概论

论述当前世界各国城市建设中必不可少的重要工程设施类型之一——生活垃圾处置工程。总结当前垃圾处置的主要方式,分析卫生填埋在各种处理方式中独具的优势,并简要介绍组成卫生填埋工程的各个部分及其功能;论述垃圾填埋体中进行的各种化学和生物化学作用及其变化;指出垃圾填埋体是其中的核心部分,填埋体结构的优化设计是控制污液污染地质环境的关键,提出填埋体结构设计的技术路线和系统方法。最后,根据当前卫生填埋场实施中存在的问题,为进一步有效地控制垃圾填埋处置对地质环境污染中的研究不足,提出意见和建议     

Efficacy of Fine-Grained Soil as Landfill Liner Material for Containment of Chrome Tannery Sludge

This paper evaluates the potential use of a fine-grained soil obtained from a site in West Bengal, India, as a suitable landfill liner material for the containment of hexavalent chromium from tanning waste sludge. The physico-chemical properties of the soil were determined. The soil adsorption affinity for hexavalent chromium was also assessed through adsorption batch and breakthrough column tests. The zero point charge (pH_zpc) of the soil was found to be 7.3. The batch kinetics and column tests results indicated that the soil liner possesses a relatively good hexavalent chromium adsorption capacity at natural or slightly alkaline condition. The adsorption results showed that the hexavalent chromium uptake by the soil follows both Langmuir and Freundlich adsorption isotherms. This study also illustrated that the hexavalent chromium breakthrough curve in the column experiment reached equilibrium concentration after 3.5 pore volumes (900 h). Overall, this study showed that the fine-grained soil has the potential for usage as a landfill liner or as a component of a landfill barrier system to prevent chromium contamination from the tannery waste disposal.     

Application of integrated methods in mapping waste disposal areas

An integrated suite of environmental methods was used to characterize the hydrogeological, geological and tectonic regime of the largest waste disposal landfill of Crete Island, the Fodele municipal solid waste site (MSW), to determine the geometry of the landfill (depth and spatial extent of electrically conductive anomalies), to define the anisotropy caused by bedrock fabric fractures and to locate potential zones of electrically conductive contamination. A combination of geophysical methods and chemical analysis was implemented for the characterization and management of the landfill. Five different types of geophysical surveys were performed: (1) 2D electrical resistance tomography (ERT), (2) electromagnetic measurements using very low frequencies (VLF), (3) electromagnetic conductivity (EM31), (4) seismic refraction measurements (SR), and (5) ambient noise measurements (HVSR). The above geophysical methods were used with the aim of studying the subsurface properties of the landfill and to define the exact geometrical characteristics of the site under investigation.     

Municipal solid waste landfill siting by using GIS and analytical hierarchy process (AHP): a case study in Qom city,Iran

Qom is the eighth most populated city in center of Iran, and its population growth rate is among the highest in this country. Th presence of a Great Salt Lake, petroleum potential and tourism attractions in this city sheds light on the importance of how solid waste landfill locations should be disposed, located and managed as an environmental issue. Considering the key parameters in landfill site selection, in this study a series of location analysis have been conducted to locate optimum regions for municipal solid waste disposal, using analytical hierarchy process (AHP) and geographical information system (GIS). The main factors in selecting the suitable location for waste disposal include geomorphology–hydrography, environmental–social factors and design criteria, each of which are subdivided into several categories. Criteria are selected according to the regional condition; therefore, important factors such as distance from sea and forested areas were not considered. In the next step, digital layers are weighted and classified according to the available standards and expert judgment. Then, analytical multi-criteria decision-making algorithms as AHP and weighted linear combination are applied upon existing layers in GIS. The results show that by implementing the AHP method in this region only 7% of the study area has a very good and appropriate condition for landfill location and the field observation confirms them. Finally, considering the environmental effects of landfill, appropriate locations are suggested.     

Magnetic properties and heavy metal content of sanitary leachate sludge in two landfill sites near Bandung,Indonesia

Magnetic properties and heavy metal content of landfill leachate sludge samples from two municipal solid waste disposal sites near Bandung, West Java, Indonesia, and their correlation with heavy metals are studied in the present work. Leachate was found to be sufficiently magnetic with mass-specific magnetic susceptibility that varies from 64.8 to 349.0 × 10⁻⁸ m³ kg⁻¹. It is, however, less magnetic than the soils around the landfill sites. The magnetic minerals are predominantly pseudo-single domain and multidomain magnetite. Leachate samples from the older but inactive disposal site, Jelekong, are found to be more magnetic than that from Sarimukti, the younger and active site. The enhancement of leachate due to the soil-derived ferrimagnetic particles is possibly the same for both Sarimukti and Jelekong. The fact that strong correlation between magnetic parameters and heavy metals is observed in Jelekong but is absent in Sarimukti suggests that the use of magnetic measurement as a proxy measurement for heavy metal content in leachate is plausible provided that the magnetic susceptibility exceeds certain threshold value. Moreover, the accumulation of magnetic minerals and heavy metals in leachate might depend on the activity and the age of landfill site.     

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.     

Performance-based landfill design: development of a design component selection matrix using GIS and system simulation models

Designing environmentally safe and economically feasible landfills can be a challenging task due to complex interactions that need to be taken into account between landfill size, waste and site characteristics. The main focus of this study is, by interfacing the geographic information systems (GIS) with system simulation models (SSM), to develop a methodology and a landfill design component selection matrix that can enable the determination of landfill design components providing the desired performance with minimal design details. In this paper, the conceptual framework and applications of the developed methodology demonstrating the selection of landfill design components that are suitable for the existing site conditions are presented. The conceptual model defines design variables, performance criteria and design components of a landfill. GIS and SSM are used to handle the site-specific data and to evaluate the landfill performance, respectively. Results indicate that the landfills having the same design characteristics show different performance under different site conditions; therefore, a landfill design that is technically and economically feasible should be selected on the basis of performance.     

哈尔滨市区垃圾堆放场环境地质条件适宜性评价

城市垃圾堆放场所由于设置不合理,对周边环境和地下水已造成了不同程度的影响,垃圾堆放场的选址成为保证城市大气、地表水、地下水环境不受污染的首要问题.根据垃圾堆放场地的环境地质条件,选择黏性土厚度、土层渗透系数、地下水水位埋深、地下水供水意义及水质状况、地下水是否流向城区5个评价因子,运用综合指数法,对哈尔滨市区15个现有的垃圾堆放场的环境地质条件适宜性作了评价.     

Hazardous waste landfill site selection in Khorasan Razavi Province, Northeastern Iran

The disposal is the final step of any hazardous waste management plan. An inappropriate landfill site may have negative environmental, economical, and ecological impacts. Therefore, landfills should be sited carefully by taking into account various rules, regulations, factors, and constraints. In this study, candidate sites for hazardous landfills in the northeastern Khorasan Razavi province are determined using the integration of geographic information system and landfill susceptibility zonation methods. For this, the inappropriate areas were first removed from the model, and the suitability of remaining regions were evaluated using 15 different criteria in two steps. With this done, nine candidate sites were selected as the most suitable locations. Finally, the selected landfill sites were proposed based on environmental impact assessment (Leopold matrix) and economical studies. This study shows that Maasumabad, Kheirabad, Mayamey, and Yonsi are the best locations for the constitution of landfill in Khorasan Razavi province, respectively.     

Small-scale landfills: impacts on groundwater and soil

In Brazil, the large quantities of solid waste produced are out of step with public policies, technological developments, and government budgets for the division. In small municipalities, the common lack of technological knowledge and financial conditions for suitable waste disposal has resulted in a large number of illegal dumps. Therefore, small sanitary landfill facilities are working with simplified operations focusing on cost reduction and meeting the economic and technological standards of the city without endangering the environment or public health. Currently, this activity is regulated at a federal level although there is some uncertainty regarding the risk of soil and aquifer contamination as theses facilities do not employ liners. Thus, this work evaluates a small landfill to identify changes in soil and groundwater using geotechnical parameters, monitoring wells, and geophysical tests performed by electrical profiling. It is verified that based on current conditions, no contaminants have migrated via underground water aquifers, and overall no significant changes have occurred in the soil. It is concluded that, despite its simplicity, the method investigated is a viable alternative for the final disposal of municipal solid waste from small cities, especially in developing countries.