Large scale failure of the external waste dump at the “South Field” lignite mine, Northern Greece

This paper presents the failure process of the external waste dump of the South Field Mine, the major open pit mine in Greece. The waste materials of the mine were deposited in three phases, forming an average inclination slope 10% and a total height of 110 m from the ground surface. The failure occurred when the third phase of the deposit was initiated. The high moisture content of the waste materials and their deposition over a spring, choking its flow, had as a result the development of high pore water pressure in clayey and marly materials in the base of the deposit. As a consequence, a large scale slope failure incident occurred. The landslide involved the mobilization of waste material in the order of 40 Mm³, while the material that moved outside the boundaries of the waste dump was in the order of 2.5 Mm³. The stability of the waste dump was investigated using the limit equilibrium analysis and different types of models.Limit equilibrium analyses were performed using different methods and considering the clay layer of small shear resistance that exists in the base of the deposit. They do not indicate activation of failure mechanism, only that there is a combination of high pore water pressure that developed in the deposit because the covering of the spring with the clayey materials of the dump.     

地质钻探废弃冲洗液污染特性及脱稳技术研究

废弃冲洗液无害化处理是落实绿色勘查理念的一项重要工作。通过室内测试分析与现场调研,对地质钻探不同领域的钻孔废弃冲洗液进行污染特性研究,了解其基本性质以及对环境的影响方式。结合湘桃地2井废弃冲洗液开展脱稳技术室内研究,对破胶剂及絮凝剂进行了优选,并获得了脱稳处理的基础配方。实验结果表明,经过处理后废弃冲洗液能实现快速脱稳絮凝,COD、悬浮物、色度等污染指标大幅下降,为下一步深度处理实现无害化排放创造了有利条件。     

瑞典硫化物矿山尾矿淋滤水的控制

在瑞典,硫化物矿尾矿污染水的淋滤造成巨大的环境污染问题。本文概述一项利用天然土覆盖尾矿、最大限度地减少淋滤水的调查报告。研究表明,天然土渗水性是如此之高,以致于起不到明显的隔水效果。天然土盖层只能减少高降雨量期或迅速化雪期的渗水量,而且只对淋滤水峰值有作用。但是,作为一种蓄水体,位于尾矿顶部的密封盖层具有重要意义,它可以增加蒸腾损失。     

Mineralogical and geochemical behavior of mill tailing material produced from lead-zinc skarn mineralization,Hanover, Grant County,New Mexico,USA

Mineral extraction and processing, especially metal mining, produces crushed and milled waste; such material, exposed to weathering, poses the potential threat of environmental contamination. In this study, mill tailings from inactive Pb-Zn mines in New Mexico, southwest USA, have been examined for their potential environmental impacts by means of detailed mineralogical and geochemical characterization. The principal ore minerals remaining in the tailings material are sphalerite, chalcopyrite, and very minor galena, smithsonite, and cerrusite, accompanied by the gangue minerals pyrite, pyrrhotite, magnetite, hematite, garnet, pyroxene, quartz, and calcite. White precipitate occurring on tailings surfaces is composed of gypsum and hydrated magnesium sulfates. Pyrite is mostly unaltered or shows only micron-scale rims of oxidation (goethite/hematite) in some surface samples. This iron oxide rim on pyrite is the only indication of weathering-derived minerals found by microscopy. There are variations in element concentrations with depth that reflect primary variations through time as the tailings ponds were filled. Cadmium and Zn concentrations increase with depth and Ag and Pb are low for the uppermost core samples, while Cu, Ni, and Co concentrations are generally high for the uppermost core samples. These elemental distributions indicate that little or no leaching has taken place since emplacement of the tailings because no accumulation or enrichment of these metals is observed in Hanover tailings, even in reducing portions of tailings piles. Element concentrations of surface samples surrounding the tailings reflect underlying mineralized zones rather than tailings-derived soil contamination. We observed no successive decreasing metal concentrations in prevalent wind directions away from the tailings. Stream sediment samples from Hanover Creek have somewhat elevated Zn, Cd, and Pb concentrations in areas that receive sediments from erosion of the tailings. However, input from tributaries downstream of the ponds appears to be principal source of heavy metals in Hanover Creek. The results of this study indicate that there is low risk for groundwater heavy-metal contamination from Hanover tailings. Tailings material do not show significant geochemical oxidation/alteration or metal leaching with depth. Our studies indicate that neutralizing minerals present in the tailings are sufficient to keep the tailings material chemically stable. Geochemically, however, tailings materials are being eroded and may pose a threat to Hanover Creek via siltation.     

Simplified evaluation for swelling characteristics of bentonites

Bentonite is currently planned to be used as buffer and backfill materials for repositories of high-level nuclear waste because these materials must have the swelling characteristics to seal the waste. In the design for buffer and backfill materials, we must choose the adequate bentonite among many kinds of bentonite in the world. The database of the swelling characteristics of various bentonites and its evaluation will be available when we will select the adequate bentonite. For this purpose, this study performed the laboratory tests on the swelling pressure and swelling deformation of four kinds of bentonite produced in Japan and the United States. These bentonites have different physicochemical properties. This study investigated the characteristics of swelling pressure and swelling deformation from the viewpoint of the physicochemical properties of each bentonite. Furthermore, this study also proposed the simplified evaluation of swelling characteristics of various bentonites on the basis of microscopic analysis.     

关于尤卡山项目的一些思考

简要论述了美国尤卡山项目研发的历史进程,讨论了该项目目前的进展状态,以及由此引出可供我国高放废物地质处置研发工作值得思考的若干问题。笔者认为,目前尤卡山项目进展受阻的主要原因是政治因素,而不是场址的自然条件和科学技术因素。关于该项目的不同意见之争还将会继续下去,最后可能只有通过进一步的科学论证和法律途径得以解决。     

关于首饰清洗废油的处理研究

经过车花加工后的首饰、表面残留有丁烷橡胶胶质、芳香剂、有机酸等污垢,使首饰表面失去光泽。这些污垢可以用表面活性剂清洗,也可以用溶剂汽油（行话称白电油）清洗。如用白电油清洗,清洗后的白电油颜色发黄,粘度变大,极易造成环境的污染。对清洗废油处理是首饰厂家的棘手问题。现在的处理方式有三种：１）燃烧。会产生较大的浓烟,造成环境污染;２）分馏。由于批量小,分馏器不能常开,分馏的能耗较大;３）粘土处理。能耗低,但粘土脚料难于处理,首饰厂家只能采取交纳治污费和定期把废油送往特种废料处理站烧掉的办法,这增加了废…     

历史遗留损毁土地调查内容与调查方法探讨

掌握历史遗留损毁土地现状“家底”,是县级以上国土资源部门履行复垦责任的重要内容之一,同时,损毁土地调查成果质量也直接影响后期评价、复垦规划、复垦实施和复垦动态管理的科学性和有效性.该文基于实践经验法、对比分析法、理论分析法等方法,探讨了历史遗留损毁土地的内涵,明确了调查基本单元,提出了调查内容体系、调查方法和技术路线,对指导历史遗留损毁土地调查实施和贯彻落实《土地复垦条例》具有重要意义.     

PLACE MAKING,HAZARDOUS WASTE,AND THE DEVELOPMENT OF TOOELE COUNTY,UTAH*

ABSTRACT. Declining populations, aging inhabitants and infrastructure, limited economic opportunities, and under‐ or unappreciated natural environments characterize a number of rural communities in the western United States. Faced with the challenges of providing for their residents, some of these communities have chosen to permit undesirable land‐use activities, including the disposal of hazardous or nuclear waste. Central to the development of such sites is how a place is perceived and portrayed. Our purpose in this article is to examine how a dominant perception and portrayal of one such place—Tooele County, Utah—was created and used to facilitate the development of hazardous‐waste‐disposal sites. We use the geographical concept of “place” to illustrate how meanings and values are attached to a region in order to justify its becoming what it is and how such views persist.