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40 Uppsatser om Tailings dams - Sida 1 av 3

Dammsäkerhetsutvärdering samt utformning av dammregister och felrapporteringssystem för svenska gruvdammar

A lot of mine waste rock and tailings arise from all mining processes and have to be stored in an appropriate way. Tailings are deposited in impoundments retained by Tailings dams. The objective of Tailings dams is to retain the slurry from the mining process and in that way prevent spill into the surroundings that might be harmful for the environment. Tailings dams are often constructed as staged embankments so that construction costs and demand of materials are spread more evenly over the period of deposition.The objective of this thesis has been to compile information about and evaluate events at Swedish Tailings dams and also to develop a collective database for all Swedish mining companies for all Tailings dams and all events that occur at Tailings dams.Information about 60 events at Swedish Tailings dams has been gathered and evaluated. The evaluation has been performed by comparison between and analysis of individual parameters and also by use of a multivariate statistical method called PLS.

Landvinning : scenarier för efterbehandling och gestaltning av Aitikgruvan, Gällivare

Open pit mining creates huge amounts of tailings and waste rock deposits. Due to it's content of sulphide minerals, predominantly pyrite (FeS2), there is a risk of oxidation and formation of acid water containing heavy metals, known as Acid Rock Drainage (ARD). To prevent the process of oxidation, the tailings and waste rock have to be reclaimed. The most commonly used methods of reclamation are a coverage of water or soil. Mining also results in a large-scale interference in the landscape that will make an eternal change of its appearance.

Islastens inverkan på brottsannolikheten för glidning och stjälpning av betongdammar

There are many old dams in Sweden and, since few dams are constructed today, the main task in risk assessment on the existing dams is often to reduce the risk of failure. RIDAS (Swedish Guidelines on Dam Safety) is used when designing new dams and assess the existing ones. The guidelines include stability requirements for different failure modes, e.g. overturning and sliding, which imply that the load effect from e.g. uplift and ice load need to be less than the resisting loads or moments.

The behaviour of foals before and after weaning in group

Weaning is a standard procedure at most studs, and the methods of weaning varies greatly. The method used at the stud in this particular study is supposed to decrease stress. The purpose of the study was to compare the behaviour of foals in group before and after stepwise removal of their mares. Standardbred foals with their mothers were kept in three different groups at pasture (12, 11 and 11 foals, respectively, mixed sexes). They had free access to silage and the foals were fed concentrate in a creep-feeding area. By the time the foals were 5 months old, the mares were stepwise removed from the pasture.

Säkerhetsklassificering av dammar : En kartläggning av system i Sverige, Norge, Finland, Schweiz, Kanada och USA

In a comparing survey this thesis investigatesclassification systems for dams in Sweden, Norway,Finland, Switzerland, Canada and USA. Theinvestigation is aiming at an understanding of howpotential consequences of a dam failure are takeninto account when classifying dams. Furthermore,the significance of the classification, regarding therequirements on the dam owner and surveillanceauthorities concerning dam safety is considered andreviewed. The thesis is pointing out similarities anddifferences in the line of dam safety.The survey of dam safety is firstly based upon legalrequirements in the different countries andsecondly on guidelines regarding dam safety. Damowners generally are ultimately responsible for thesafety of their dam, and often have their ownroutines regarding how this safety is to be achieved.In this thesis, however, the legal requirements aremainly focused upon.The investigation has resulted in an outlining ofeight areas, where the classification systems in thevarious countries have been compared.

Neutral bolagsskatt? : Analys om SOU 2014:40 skapar neutralitet mellan lånat och eget kapital

This paper examines the power producing dams along the Ume-river as an integral part of and a result from the urbanization process in Sweden during industrial capitalism. The aim of the paper is to contribute to the knowledge of the urbanization process in Sweden in general and of its traces along the Ume river in the county of Västerbotten in particular. The paper applies the theory of concentrated urbanization and extended urbanization put forward by Neil Brenner and Christian Schmid (2015) and argues that the building of power producing dams along the Ume-river is part of an extended urbanization process. This becomes particularly evident when examining the vast physical structures that is the dams, situated in an otherwise remote and sparsely populated area. These vast physical structures are also very well connected to a nation wide electric grid that has connections to bordering countries as well.

ABL:s utvidgade värdeöverföringsregler då ett aktiebolag är komplementär i ett kommanditbolag : Utgångspunkt ur NJA 2014 s. 604

This paper examines the power producing dams along the Ume-river as an integral part of and a result from the urbanization process in Sweden during industrial capitalism. The aim of the paper is to contribute to the knowledge of the urbanization process in Sweden in general and of its traces along the Ume river in the county of Västerbotten in particular. The paper applies the theory of concentrated urbanization and extended urbanization put forward by Neil Brenner and Christian Schmid (2015) and argues that the building of power producing dams along the Ume-river is part of an extended urbanization process. This becomes particularly evident when examining the vast physical structures that is the dams, situated in an otherwise remote and sparsely populated area. These vast physical structures are also very well connected to a nation wide electric grid that has connections to bordering countries as well.

The laboratory rat : improved welfare for mothers andpups through breeding in an enriched environment?

Maternal behaviour is crucial for the development of the rat pups? behaviour and stressresponses later in life. There are numerous studies evaluating the effects of the dams?behaviours on the pups, but not many addressing what can be made for wellbeing of the ratdams when breeding. Few studies have addressed the question of how the commonly usedrearing environment effects the dams? behaviour and in the long run how it effect the ratsreared to become our research models.

Den urbaniserade Umeälven : Vattenkraftverken som utsträckt urbanisering

This paper examines the power producing dams along the Ume-river as an integral part of and a result from the urbanization process in Sweden during industrial capitalism. The aim of the paper is to contribute to the knowledge of the urbanization process in Sweden in general and of its traces along the Ume river in the county of Västerbotten in particular. The paper applies the theory of concentrated urbanization and extended urbanization put forward by Neil Brenner and Christian Schmid (2015) and argues that the building of power producing dams along the Ume-river is part of an extended urbanization process. This becomes particularly evident when examining the vast physical structures that is the dams, situated in an otherwise remote and sparsely populated area. These vast physical structures are also very well connected to a nation wide electric grid that has connections to bordering countries as well.

Fotogrammetrisk analys av kornstorleksfördelningeni erosionsskydd vid kraftverksdammar

This master thesis was made to investigate the possibilities of using the Matlab-basedsoftware Basegrain to determine grain size distributions of erosion protections onhydropower dams. Basegrain is a photogrammetric tool developed to generate grainsize distributions and other information about coarse flood sediments by analyzing adigital photo of the stone bed. The investigation was made by validating the ability forBasegrain to assess grain size distributions of various materials smaller than the blocksused in an erosion protection by comparing sieving results or manual measurementswith the results obtained by the program. A statistical comparison was then made bycomparing the results from sieving and the program. The possibilities of using thesame method on existing hydropower dams were then investigated by determiningwhether the method was practically viable or not.The results showed that Basegrain generated grain size distributions for coarse gravelthat were very close to the sieving results.

Att påverka en samhällsdebatt : En retorisk studie av organisationen Ruter Dams strategiska kommunikation

Det har aldrig varit så lätt att uttrycka sin åsikt och samtidigt så svårt att faktiskt göra sin röst hörd som det är idag. För att nå ut med sin åsikt måste man uttrycka sig på rätt sätt och i rätt forum. Den här uppsatsen granskar hur man kan påverka en samhällsdebatt genom strategisk kommunikation och uppnå en förändring som kommer från publiken man riktar sig till. Uppsatsen sammanför retorik med strategisk kommunikation och undersöker specifikt hur organisationen Ruter Dam arbetar för att påverka jämställdhet inom svenskt näringsliv. Analysen åskådliggör hur Ruter Dam arbetar mot ett jämställt näringsliv med utgångspunkt i den retoriska situationen, publiker, core message och stakeholders.

Fröåtjärns föroreningshistoria : Utredning av hur metallbelastningen varierat över tid med hjälp av sediment som ett naturligt historiearkiv

The metal mining history goes thousands of years back. The downside of the mining industry is the large amount of tailings created during the mining operations. Drainage and leaching of heavy metals from these tailings may cause major environmental problems including acid mine drainage and leaching of heavy metals. This study examines a pond located near an old mining site, where part of the old mining facility has been recently (1990) restored. The objective was to assess eventual metal contamination from historical mining and the recently performed restoration using a sediment core as a natural archive of historical metal inputs to the pond.

Milk yield and composition in Swedish landrace goats (Capra hircus) kept together with their kids in two different systems

Swedish goats are mainly held for cheese production and therefore, both milk quality and composition are of great importance for dairymen. Today, only few data exists on milk composition from Swedish dairy goats and the casein content is still unknown. One way to reduce the work load for goat farmers and increase animal welfare can be to keep goats and kids together for longer periods. The aims of this study were to investigate how milk yield and composition were affected when kids suckled their dams during 8 weeks, and to measure the casein content on farm level by a mid-infrared spectroscopy method, previously calibrated for goat milk. Lactating goats were kept in two different MIX- systems where the dams are both suckled and milked.

GIS för fastighetsrättsliga frågor inom energibranschen

The purpose with the work is to study Fortums activities with hydro power plants, dams and reservoirs mainly in a premise jurisdictional perspective and to show how GIS would be a helpful tool for the future.A great deal of the information that the Generation Hydro-division at Fortum are managing have a spatial element. That means that it is possible to spatially join this information to a geographical polygon, line or point. This information is today gathered from several different sources, such as files, paper maps and digital data of several kinds. A Geographic Information System (GIS), as and aid besides the ordinary tools should be an effective support in the everyday work with questions of a premise jurisdictional nature.The goal of this work is to account for how to organize, present and analyse geographic information. We will show how to link from the map to traditional tools such as calculation- and register programs.

Dammsäkerhetsanalys via stabilitetsberäkningar för Långströmmens kraftverk : En jämförelse mellan olika dimensioneringsmetoder

A detailed dam safety evaluation (in Sweden called FDU) was performed in 2009 by WSP where stability control was performed for Långströmmen power plant with associated spillways. This evaluation concluded that stability could not be ensured, and risk of sliding occurred. The evaluation is based entirely on the recommendations outlined in RIDAS, the power companies guidelines for dam safety, and it is clear that extensive renovations are necessary to stabilize the dam.In this work, the stability will also be checked with guidance through new proposals on guidelines for concrete dams sliding stability, ELFORSK?s report 08:59. This report considered the guidelines in RIDAS as oversimplified, both from an international perspective, but also with regard to the current state of knowledge regarding dam safety.

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