Case studies in organic contaminant hydrogeology

The effective management of domestic solid waste and hazardous, toxic, and radioactive waste is a major problem in the area of environmental geology and water sciences over the world. This series of case studies of organic contaminants from both solid and hazardous waste disposal facilities provides examples of these problems. The facilities were investigated to determine risks and liabilities before acquisition, to determine the site hydrogeologic conditions for design of appropriate groundwater monitoring plans, and/or to determine the potential for groundwater contamination. The results of these studies and investigations by Waste Management Inc. (WMI) and its consultants have shown certain relationships in the distribution of organic pollutants to the different geologic and hydrogeologic charac teristics of each facility. In each of the case studies, all 129 priority pollutants were analyzed in private wells and/or monitoring wells at the request of regulatory agencies. The 31 volatile organic compounds (VOCs) of the priority pollutant list were the majority of the organic compounds detected and these data are evaluated in each case study. The case studies are on disposal facilities located in glacial tills, carbonaceous weathered clay soils, weathered shale, limestone bedrock, dolomite bedrock, and alluvial and sedimentary deposits. A brief discussion of groundwater quality impacts and remedial measures also is included.Presented at the Second Annual Canadian/American Conference on Hydrogeology: Hazardous Wastes in Ground Water—A Soluble Dilemma. Banff, Alberta, Canada, June 26, 1985.     

Climate change and groundwater resources in Cambodia

Climate change has become a major global concern and threatens the security of natural environmental resources, including groundwater, especially for Cambodia. In this study, literature reviews related to climate change and groundwater resources in Cambodia were evaluated to address the impact of climate change on the groundwater environment. In Cambodia, global climate change will likely affect available water resources by driving changes in the groundwater recharge and usage pattern. Despite a general increase in the mean annual rainfall, a reduction in rainfall is anticipated during the dry season, which could lead to shortages of fresh water during the dry season. The impact of climate change on water resource environments can significantly affect national economic development. Thus, strategic management plansfor groundwater in response to climate change should be established to ensure the security of water resources in Cambodia.     

江汉平原砷中毒病区地下水砷形态季节性变化特征

查明地下水中砷的时间变异性规律及机理是高砷地下水研究的难点和热点, 也是防控地下水砷污染的根本.选择在雨季前后对浅层潜水和孔隙承压水进行了动态监测.研究表明地下水砷含量和形态与地下水位波动存在明显的响应关系: 雨季开始后随着地下水位抬升, 地下水还原环境增强, As(Ⅴ)和Asp转化成As(Ⅲ), 颗粒态铁大幅降低, 导致水中溶解的砷和铁大幅增加, 地下水砷含量在雨季达到最高且As(Ⅲ)所占比例达到90%;雨季结束后随着水位逐渐降低, 地下水中As(Ⅲ)所占比例和溶解的砷含量下降.农业活动对浅层潜水砷形态季节性变化有明显的影响.孔隙承压水的砷形态分布变化较浅层潜水幅度大, 其变化与水位波动存在滞后效应.自然或人为活动引起的地下水位季节性变化改变了含水层的氧化还原环境, 补给水源与地下水之间的混合过程带来新的物质输入促进地下水系统中砷的迁移转化.      

Rural women and technology in South Africa: Case studies from KwaZulu-Natal Province

This article contributes to a greater understanding of the linkages between women's roles, responsibilities and their use of technology in poor rural communities. The ways in which poor rural women conceptualize technology is examined. Furthermore, how they use their knowledge and skills to develop, modify and adapt the techniques and technical processes in which they are involved are also explored. Additionally, the links between indigenous and modern technologies in relation to gender considerations in poor rural contexts are examined. This article draws from findings of primary research undertaken in two marginalized rural communities in Kwazulu-Natal, South Africa. The study reveals that the use of technologies are highly gendered and differentiated among women. Poor rural women utilize a range of technologies in both productive and reproductive activities which are central to their livelihood strategies, especially at the household level. Furthermore, although women are adapting and innovating technologies their expertise remains largely unrecognized. A range of problems and constraints exist which limit women's access to and use of technologies. A key tension identified in the study is that between the use of locally-based, indigenous technologies and modern, external technologies. This revised version was published online in July 2006 with corrections to the Cover Date.     

低空高精度磁测方法在未知区找铁的应用——以柬埔寨罗文真穹隆为例

罗文真穹隆构造区属柬埔寨北部暹粒-上丁成矿带,主要矿种为铁.已发现铁矿床主要有表生残坡积矿和原生矿两种形式,矿体呈层状、似层状、囊状、透镜状,矿物组合为赤铁矿-磁铁矿-褐铁矿.已发现主要铁矿床有格高铁矿、石山铁矿、诺东山铁矿.穹隆内大范围未知区与已知矿床具有类似的成矿地质背景.为快速评价未知区内铁成矿背景,利用动力三角翼低空高精度磁测技术,综合地质-遥感信息进行找矿预测,并结合地面磁测进行验证.共圈定12个找矿预测区,其中4个为一级找矿靶区,为下一步的主要工作方向.     

Modeling and management of pit lake water chemistry 2: Case studies

Pit lakes, a common product of open pit mining techniques, may become long-term, post-mining environmental risks or long-term, post-mining water resources depending upon management decisions. This study reviews two published pit lake modeling studies and one pit lake monitoring program in order to increase the transparency of approaches used in pit lake prediction and management. The first model is a two-year limnological simulation of the existing Dexter pit lake, Nevada, USA that accurately modeled temperature profiles, salinity profiles, and turnover events observed between 1999 and 2000. The second model is a 55-year prediction of a future pit lake in the Martha Mine, New Zealand that identified the need for additional mitigation and evaluated potential effects of cost-effective mitigation options. The final study reviews eight years of monitoring data collected from the Berkeley pit lake, Montana, USA, from 2004 to 2012. This study identifies changes in the physical limnology and water quality of the pit lake that resulted from metal recovery operations, and highlights the value of monitoring programs in general. Whereas these pit lakes are different in many ways, the management tools discussed herein maximized the value and understanding of the post-mining resources.     

Site response studies in Agartala Urban agglomeration

A systematic investigation using digital microearthquake recorders with short period SS-1 seismometers, covering 76 sites in and around Agartala city, has been carried out for site response (SR) studies in the area. In the northern part of the area, SR varies from 1.15 to 1.85 corresponding to peak frequency 0.76 to 0.93 Hz where soil is mostly semi-consolidated and stiffer than recent Quaternary deposits (Haora River formation). In the southern part of the area, SR varies from 1.12 to 2.42 corresponding to peak frequency from 0.71 to 0.85 Hz within the Dupitila formation (early Quaternary). It is observed that estimated SR from H/V increases from edges to middle of the Haora River valley and impedance contrast fallows the similar trend. This reflects that site response by H/V is influenced by impedance contrast, whereas computed amplification from 1-D model shows opposite trend. The maximum amplification at fundamental frequency of resonance, 1.04 Hz estimated from H/V by near to BH-7, is 2.5 times greater than the impedance contrast/ratio derived from 1-D model for same location. Relationship between resonance frequency and depth was obtained by applying quarter wavelength and Bard (2000) methodologies, which shows linearity, whereas H/V shows its nonlinearity characteristic in soil across the valley part of Haora River. Shear wave velocities, and subsequently, SPT index and factor of safety (by cyclic stress approach) were estimated from geotechnical parameters. Vs30 and site response data were used in this study for getting a first hand information about soil stiffness condition in the area. The estimation of SPT index and factor of safety could be a useful tool for delineating liquefied and none liquefied zones at various depth levels, especially where water table exists at a very shallow level. The expected liquefiable zone was observed at depths varying from 6–25 m beneath the soil bearing zones where percentage of fines is estimated to be more than 35% for the area. This knowledge about subsurface soil characteristics will be useful for the civil engineers/city planners, which can be taken into account at the time of constructing earthquake-resistant structures in the area.     

Multi-scalar inequality: Structured mobility and the narrative construction of scale in translocal Cambodia

Focusing on three neighbouring villages in Cambodia, this paper argues the need for a multi-scalar interpretation of the relationship between mobility and wealth. It analyses migrant livelihoods in both sender and receiving areas to show that single scale measurements of mobility are inappropriate in the context of translocal livelihoods because livelihoods enacted across multiple places may possess multiple values of scale and mobility, each co-existing within the same migrant lifeworld. In seeking an improved conception of these complexities, the paper has combined spatial and qualitative analysis of translocal livelihoods to highlight the linkages between mobility in multiple places. On this basis, it posits that the mobility of translocal livelihoods must be assessed at least three scales: the scale appropriate to the sending environment, the scale appropriate to the receiving environment, and the scale on which potential migrations are judged. Making use of this framework allows clear relationships to be observed between mobility and inequality in both the narratives and structures of the communities under investigation.     

Case studies on the origin of basalt

The simplified model of basalt genesis described in Part I of this series, equilibrium partial melting followed by Rayleigh-type fractional crystallization, is applied to a stratigraphically controlled sequence of basalt flows from Kohala volcano. Major-element compositions were determined for 52 samples and show a time-stratigraphic progression from tholeiites through transitional basalts to alkali basalts. Twenty-six of these samples were analyzed by isotope dilution for K, Rb, Cs, Sr, Ba and the REE, 13 for⁸⁷Sr/⁸⁶Sr, and 19 for Co, Cr, Ni and V by atomic absorption. After a simple, first-order correction for the effects of fractional crystallization (involving mostly olivine and aluminous clinopyroxene), the major element concentrations cluster tightly, and the incompatible trace elements show monotonic increases in concentration as a function of stratigraphic height. The process identification plot shows that all the (fractionation corrected) melt compositions can be explained by equilibrium partial melting of compositionally identical batches of source material. The REE and Sr are fractionated because of the presence of residual clinopyroxene. Garnet may also be present but in much smaller amounts. In this respect our results differ significantly from those of Leeman et al. (1980). The calculated chondrite-normalized REE patterns of the source are nearly flat to slightly convex upward. Therefore there is no need to invoke special mechanisms, such as metasomatic REE preenrichment of the source, in order to explain the petrogenesis of the suite of lavas. Specifically, Ce concentrations ranging from 20 to 250 times chondritic are all explained by the same calculated source pattern having a chondrite-normalized ratio of Ce/Sm=0.9±0.2. However, the normalized ratio Ce/Ba?2 shows that the source is not simply primitive mantle.     

重新审视深层油气成藏模式：以塔里木盆地为例

近年来,随着油气勘探不断向深层—超深层领域拓展,深层展现出了巨大的油气勘探潜力,同时也在成烃-成储-成藏等方面浮现出一系列科学问题。本文在广泛调研国内外相关研究的基础上,梳理了深层油气成藏环境和生、储、盖成藏要素的特殊性,重点讨论了深层油气藏在形成与演化过程中需要深入关注的四个基本问题：(1)深层中的油气生成、储集空间形成、油气相态和运移等研究,均需要以物质守恒和能量守恒基本定律为前提开展;(2)深层经历了盆地演化全过程,需要从动态演化角度研究油气成藏;(3)需要探索新的实验方法,加大对深层液态烃稳定性与保存深度下限的研究;(4)注重多学科融合与多技术交叉,解决深层复杂的地质问题。在此基础上,提出了深层油气藏最为可能的两种成藏模式：(1)中—浅层油成藏、深埋保持型;(2)长期浅埋、晚期快速深埋(凝析)气成藏型。以塔里木盆地台盆区顺北地区和库车坳陷博孜—大北地区为研究对象,应用储层地球化学分析、流体包裹体系列分析技术、方解石原位U-Pb定年技术和盆地模拟技术,对两个地区油气成藏模式进行研究。结果表明：顺北地区奥陶系深层油气藏为“早期中—浅层成藏、后期持续深埋保存”的成藏模式,油气成藏后相...     

Geotechnical aspects and ground response studies in Bhuj earthquake, India

The extent of damage and affected areas in Bhuj earthquake (26th January 2001) has provided a unique opportunity to evaluate a wide range of geotechnical issues. A large area in the Rann of Kutch experienced massive liquefaction resulting in ground subsidence and lateral flow. A large number of dams in the Kutch district suffered moderate to severe damages. Many buildings were damaged and collapsed in the city of Ahmedabad situated on the bank of the Sabarmati River. In this paper, the ground response studies at a site in Ahmedabad City along with observations of geotechnical aspects such as ground cracking, sand volcanoes and liquefaction of soils associated with the Bhuj earthquake are discussed. The ground response studies indicate that the varying degree of damage to multistorey buildings in Ahmedabad in the close proximity of Sabarmati river area was essentially due to the collapse and undesirable settlement of partly saturated silty sand deposits. Large settlements are attributed to amplification of the ground and the near resonance condition. This revised version was published online in July 2006 with corrections to the Cover Date.     

Mobile policies and policy streams: The case of smart metering policy in Australia

Geographers have become increasingly engaged with the notion of policy mobility. It is argued that in a globalised world policies have become more internationally mobile: we now live in an era of ‘fast policy’. Drawing on core concepts of mobility, neoliberalisation, and globalisation - and with a background primarily in geography and urban studies - policy mobility scholars have developed new ideas about how policies circulate internationally. In the process, however, theories of policy change developed within political science have been rather overlooked. In this paper it is shown how a political science theory with a shared interest in flows – the Multiple Streams Approach (MSA) – is complementary to policy mobilities scholarship. Two issues in particular are illuminated by the MSA: first, what constitutes policy, and, second, the role of the nation state in structuring the possibilities for, and timing of, policy change. In turn, policy mobilities scholarship highlights the different geographies of the multitude of objects, ideas, problems, processes, organisations, and regulations that constitute policy. It also raises questions about the validity of analytically separating politics from policy proposals, as advocated by the MSA. These issues are considered using the empirical case of smart electricity metering policy in Australia, in the period 2000–2015.     

Issues in public policy evaluation: the case of regional policy

This paper notes the recent growth of public policy evaluation studies and pays particular attention to those policies with avowed spatial objectives. It seeks to establish the general nature of these diverse studies and their relationship to geographical analysis. A case study examining the evaluation of regional policy in the U.K. is used to demonstrate the nature of the issues in public policy evaluation and to explore the role of geography in the rapidly growing domain, known most commonly as ‘policy analysis’.     

Participation in payments for ecosystem services: Case studies from the Lacandon rainforest, Mexico

Understanding people’s willingness to participate in projects and programmes of payments for ecosystem services (PES) has not been a key analytical concern of the scholarly literature around this new field of environmental policy and practice. This paper analyses participation in four communities benefiting from payments for biodiversity and carbon fixation in Mexico, and contrasts the results for each case with neighbouring communities that do not receive payments. We take a holistic approach that accounts for procedural rules, actors’ interactions, institutions and values, and individuals’ characteristics. We show that the nature of PES rules and the effectiveness of communication with government officers and NGOs influence resource managers’ ability and willingness to participate. We highlight community size, resource managers’ ability to diversify livelihood activities and local perspectives on the conservation of common forests, particularly sacred values and intergenerational concerns on forest conservation, as critical participation drivers. This analysis provides insights on why and how these new institutions may be attractive for some resource managers and permits to draw some recommendations for the future design of PES projects and programmes.     

The co-production of livelihoods and land use change: Case studies from South Africa and Ghana

Land use change and livelihood systems are often analyzed separately or with one “driving” the other. This “driver-feedback” relationship has been buttressed by approaches to social process that are often far too static. Actors are confronted with a bundle of choices that they must negotiate as they create pathways of change. These choices are always bound up in relations of power and the knowledges that are the conditions for and results of these relations. We suggest that land uses and livelihood are different manifestations of the social processes by which individuals and groups negotiate the everyday conditions that shape their lives. We propose a framework that extends current understandings of the relationship between land use change and livelihoods by treating social relations of power as the entry point into this complex relationship. We underpin our arguments with empirical examples from South Africa and Ghana that locate power/knowledge relations in the context of social change in both study areas.     

Landslides in Sado Island of Japan: Part I. Case studies, monitoring techniques and environmental considerations

A sufficient knowledge on the kinematics and development of landslides helps to adopt proper measures that can be used to protect slopes and the environment in general. This can be achieved by adequate monitoring programs. This paper presents the findings of intensive monitoring activities carried out on Shiidomari and Katanoo landslides found in Sado Island of Japan. More than one year of observation of the two landslides allowed defining some peculiar futures of their kinematics and style of development. The problem of slope instability in the two areas is generally accredited to various factors. But, both landslides were triggered by heavy rainfalls and snowmelt. Because of the outline of the area and the presence of relict topographic features, the Shiidomari landslide is considered to be a large-scale reactivation of old slope failures. The Katanoo landslide is, however, a first-time case. Geophysical investigations and drilling activities in Shiidomari indicated the presence of two slip planes. The deepest (80–100 m) of these is controlled by existing lineaments. Monitoring data suggests that the body of the landslide has subsided as much as 1.16 m just below the main scarp, but a centimeter in the central region. The toe sector also experienced a significant amount of subsidence, but this was counter-balanced by an uplift on the opposite side of the landslide. Hence, the landslide seems not any more active along the deepest slip surface, although it may extend upward and define a series of shallow shear planes around the crown. In the case of Katanoo, the landform characteristics, differential weathering, the road cut and groundwater fluctuations appeared to contribute much to determine the exact location of the landslide. Extensional cracks that preceded the landslide can be related to heavy rainfalls and the cold and warm cycles thereafter. Subsurface investigations and monitoring works indicated that the landslide has two slide blocks with different slip planes. During the observation period, the upper part of the landslide responded more effectively to rainfall and snowmelt than the middle and lower sections. The corresponding movements, however, appeared to settle about three months after failure. There were also little strain transmissions in boreholes and no significant change in the characteristics of the landslide. The kinematics of deformation of many of the slopes in Sado Island resembles that of Shiidomari landslide. But mass movements along highways and mountain roads are usually similar to Katanoo. Landslides of the type like Shiidomari may not show sudden and drastic failures, but are usually long lasting and can reactivate repeatedly along new, shallow shear planes. Monitoring works and long-term supervisions in these types of landslides are useful to identify impending failures and take the right measures before they brought about large-scale destruction to the environment.