Idag finns det tusentals verksamheter i Sverige som kräver tillstånd enligt miljöbalkens 9 kap 6 § då de klassas som miljöfarlig verksamhet. Vissa av verksamheterna omfattas också av Sevesolagstiftningen vilket innebär att åtgärder ska vidtas för att förebygga och begränsa följderna av allvarliga kemikalieolyckor. Vid sidan av de legala kraven väljer många företag att certifiera verksamheten enligt ledningssystemen ISO 14001 och OHSAS 18001, vilka ställer krav på verksamheten att arbeta med miljö och arbetsmiljö på ett strukturerat sätt. De legala kraven ovan samt ledningssystemen innebär att berörda företag ska arbeta med riskinventering samt kommunikation till externa intressenter. Nynas raffinaderi Nynäshamn är en verksamhet som omfattas av tillståndsplikt enligt miljöbalken och Sevesolagen, samt innehar certifikat enligt ISO 14001 och OHSAS 18001. Syftet med det här examensarbetet var att genom en enkätundersökning studera riskperceptionen, dvs. upplevelsen av risker, hos närboende till Nynas raffinaderi Nynäshamn. Även riskkommunikationen som sker mellan Nynas raffinaderi Nynäshamn och närboende till raffinaderiet undersöktes genom enkäten samt en intervju med Nynas, där de närboendes uppfattning om kommunikationens betydelse för den upplevda risken beaktades såväl som Nynas syn på kommunikationen. Enkäten skickade ut till 406 personer i Nynäshamn och gav svarsfrekvens på 37,4 %. Adresser togs fram slumpmässigt via hitta.se. Resultatet visade på signifikanta skillnader mellan samtliga jämförda grupper i enkätundersökning, utom mellan personer med olika avstånd till Nynas. Flest signifikanta skillnader fanns det i svaren mellan män och kvinnor. Slutsatserna var att män tillsammans med personer som är 50 år eller äldre och personer som skickade in sina svar innan den 1/3 då Nynas polisanmäldes för miljöbrott, i större utsträckning upplever riskkommunikationen som god jämfört med kvinnor, personer under 50 år samt personer som skickade in sina svar efter den 1/3. De största upplevda riskerna var utsläpp av farliga ämnen till luft, mark och vatten samt brand; det fanns också skillnader mellan män och kvinnors riskperception. Kvinnor tenderade att värdera risker högre än män. Vidare tillhandahåller Nynas en rad olika tjänster och aktiviteter för att sprida information till närboende.

The purpose with this essay is to highlight the environmental risk that black-carbon aerosols represent to the ice melting in the Arctic. When the ice melting in the Arctic and other climate-related issues are highlighted, the focus is primarily on carbon dioxide and the risks related thereto. Black-carbon aerosols and their environmental effects are much more unknown to most people. The effect that black carbon exerts on the Arctic ice melting is mainly that it causes a decrease in albedo. The term albedo is a measure of the proportion of the sunlight that hits the surface and then is reflected. A reduction in albedo means that a greater proportion of the incoming solar radiation is absorbed by the surface area. This is exactly what happens when black-carbon aerosols end up in the Arctic. Because of the black colour of the aerosols, the surface where the aerosols are deposited becomes darker, which means an increased light absorption, which in turn heats the surface and accelerates the ice melting process. The essay deals with the subject based on the environmental risk paradigm. That means that the focus is placed on the following three steps: the -risk assessment, the -risk communication and the -risk management. The risk assessment is used to assess the threat posed by black-carbon aerosols. Where and how black carbon occurs, and its ability to disperse to the Arctic constitute an important part of the risk assessment. Other environmental risks and especially the health risks associated with black carbon have also to some extent been treated in this essay. This is primarily because of the fact that those other environmental hazards that are not related to the Arctic may be relevant when it comes to increasing the incentives to reduce the emissions of black carbon. The facts that emerge in the risk assessment clearly indicate that Southeast Asia is of great importance when it comes to black carbon that ends up in the Arctic. The risk management is used to analyse the methods which are most appropriate and profitable in terms of reducing the emissions. The available technologies to reduce the emissions of black carbon are also treated. It turns out that the profitability to make emission reductions is greatest in Southeast Asia. The fact that the profitability to make emission reductions is greatest in the part of the world where the emissions are greatest indicates that there is a great potential to overcome the problem. The countries in Southeast Asia may need support from the Western countries when it comes to implementing measures in order to reduce the emissions. The risk communication is a part of the environment risk paradigm that is constantly needed in order to communicate the risks at various levels. An important conclusion of this essay is that the environmental risk communication between researchers and policy makers is insufficient. An improvement of this could lead to more vigorous measures to be taken in order to overcome this problem.

The BABEL project (Baltic And Bothnian Echoes from the Lithosphere) was a collaboration among British, Danish, Finnish, German and Swedish geoscientists to acquire deep-crustal reflection and wide-angle refraction data in the Baltic Shield and Gulf of Bothnia. In 1989, the collection of 2,268 km of deep marine reflection seismic data was carried out. BABEL line 7, one of several BABEL profiles, is the focus of this study and runs north of the Åland islands, in an E-W direction in the Bothnian Sea, east of the city of Gävle. The previous seismic image of the BABEL line 7 displays a considerable change in the reflectivity pattern from a weak reflective lower crust in thewest to a more highly reflective lower crust in the east, interpreted to be due to a transition from a stiff crust to a plastic crust from the west to the east. The seismic results were presented by the BABEL Working Group (1993) which focused on imaging and interpreting deep crustal structures as well as assessing the seismic velocities within the crust, the depth and nature of the Moho discontinuity and the seismic reflectivity texture in the crustal geological structures. Early Proterozoic plate tectonics in the Baltic Shield was also suggested from the reflection seismic data.The BABEL line 7 reflection data were collected with a profile length of 174 km, a group of 48 air guns towed at 7.5 m depth, and 3000 m long streamer, 60 hydrophones spaced at 50 m intervals towed at 15 m depth. Seismic data were acquired for a 25 s record length using a 4 ms sampling interval and a 75 m shot interval. Seismic data are characterized by strong source-generated noise at shallow travel times and strong but randomly distributed spurious spikes at later arrival times. In this thesis, the seismic data along BABEL line 7 were recovered and re-processed. Modern processing techniques that were not available previously, were used. A special emphasis on the shallow parts of the seismic data was given and resulted in revealingreflections as shallow as 300 ms. Some of these reflections seem to be a continuation of the deeper ones and now appear to come to the surface which can now improve thecorrelation with the surface geology. Two major apparently moderately dipping shear zones are now interpreted to reach to the surface in the re-processed data in comparison with the previous work.The deep reflections are also enhanced together with the improvement in the shallow parts which provide further insights about the nature of the Moho and its geometry along BABEL line 7. The re-processed seismic image demonstrates the potential in improving shallow and deep crustal structures along the BABEL offshore seismic data.

Seismic reflection surveying is a powerful method to explore the structures of the Earth’s crust and describe it is layers. It is also used extensively in the oil industry. Offshore seismic profiles were acquired in southern Sweden (Skane area) for petroleum exploration purposes, but no productive fields were discovered in that area. The seismic reflection data were collected and processed in the 1970s. The purpose of this thesis is to reprocess some of the seismic profiles from the 1970s with new processing programs to improve the results and compare it with the previous results. Offshore lines 208, 206, 212 have been selected in this project because they cross each other and are close to a borehole with sonic data. The borehole lies close to lines 208 and 212 as seen from the Skane area map. Also this report can be used to introduce the reader to fundamentals of seismic data processing. The processing was done using Claritas software by applying standard processing steps to produce migrated stacked sections for every line as a final product.

The Hammerfest Basin was formed through downfaulting in Late Jurassic-Early Cretaceous times, allowing the deposition and preservation of Jurassic sediments which later were covered by thick Cretaceous sequences filling in the basin. This study has been conducted along the southern margin of the Loppa High to develop a complete sequence stratigraphic framework and to map Early Cretaceous Knurr Formation turbidite lobes along the slope of the High. Six seismic profiles have been selected for interpretation along the southern margin of the Loppa High on the basis of the availability of good quality data. A complete sequence stratigraphic framework has been developed to mark the major surfaces (Sequence Boundary, MFS) by geologic characterization of high-resolution seismic reflection geometries (truncation patterns, sigmoidal reflections) and seismic facies using the coarsening-up, fining up and blocky GR log motifs from both the offset wells and the wells located on the seismic section. Two Wheeler Diagrams (Chronostratigraphic Charts) have been constructed for type sections to obtain better insight into the time relationships of the depositional system, and define surfaces of non-deposition, condensation and erosion. WinPICS interpretation software has been used for seismic interpretation. Sequence stratigraphic analysis has been carried out on two scales (3rd order and 2nd order cycles). The whole sedimentary package is divided into various sequences and system tracts. In addition to a detailed sequence stratigraphic analysis to investigate the hydrocarbon prospectivity, an Early Cretaceous turbidite sand lobe has been mapped (LHSG-84-428) using seismic stratigraphy and compared with a drilled analogue (well 7122/2-1). Two paleogeograhic maps have also been constructed to show the Early to Late Cretaceous progradation and accommodation space filling in the Hammerfest Basin.

In August 2008 and June 2009 two sets of airborne measurements were made in Falun and Borlänge, respectively, by the Geological Survey of Sweden (SGU). The purpose of these campaigns was to test the new Multi Frequency Receiver (MFR) instrument called ADU07 for the collection of airborne data in the VLF and LF bands. This system was designed by Metronix and adapted by Uppsala University together with the SGU in the frame of a joint research project. The SGU in its bedrock mapping program routinely records VLF signals from only two transmitters in the frequency band of 14‐30 kHz. The RMT technique also makes use of electromagnetic signals in both the VLF and LF bands in the frequency range of 10‐250 kHz. By measuring all the three magnetic field components in this broader band, the data acquired by the new MFR system can provide high lateral and vertical resolution compared to the VLF data. This can be done by applying the concepts used for the EnviroMT. The joint research therefore aims at extending the VLF technique currently used by the SGU for geophysical investigations and whereby generating improved and more detailed anomaly maps. The airborne measurements with the ADU07 system were performed by continuously recording the three magnetic field components with a sampling frequency of 512 kHz in three channels. The prior evaluation of the data gave good results in the beginning. However, later tests showed that there were some near field sources onboard the aeroplane that contaminated the data and highly affected the estimation of transfer functions from the radio transmitters’ signals. The noise was basically generated by other measuring instrumentation and the common power supply used to feed both the ADU07 and the PC controller. The main aim of the present project is to develop a processing method that identifies frequencies from these near field sources and filters them out from the spectral ADU07 data. This work has been carried out by writing MATLAB routines. After the filtering, more reliable transfer functions that provide relevant information about the Earth’s resistivity structure can be estimated. Different methods were applied in order to detect the noise in the data. The mean value of the real part of the vertical magnetic field component (Hz) and the scalar tippers were firstly calculated along the profiles. These values should normally be close to zero. These methods did not give any valuable information since no patterns could be seen in the results. Afterwards, the vertical signal‐to‐noise ratio (VSNR) was calculated for every frequency at each station. This criterion showed that, for the first campaign, there were practically two sets of noise frequencies in the spectra: the first group corresponds to the even and odd harmonics of frequency 8 kHz, and the second group to frequency 23.47 kHz and its harmonics. For the last campaign, frequency 10.28 kHz and its harmonics were identified. The band averaging technique that splits the main frequency band into 9 overlapping sub‐bands with 1 octave of width was used. Finally, Prediction Errors (PE’s) were estimated to detect the remaining noise. A threshold was then chosen in order to remove from the spectra those frequencies with a PE above 3 and up to 20% of the number of transmitters in the sub‐bands. These processing steps improved considerably the tipper behaviour for the VLF band along the profiles, although some noise was also added. For the LF band, the filtering steps seem to have worsened the data quality and therefore the tipper estimation. The removal of important frequencies that were hidden in the high noise levels and the useof some other instruments during the data collection could be the causes of these responses.

In this thesis I have investigated the upper bounds on the possible presence of radiogenic heat sources in the inner core of the Earth, using both steady state and transient models, built during this work. Necessary theory for this and model descriptions are collected into appendices at the end of this work. In addition, the published literature is reviewed for various formation scenarios, modelling of the inner core, theoretical and experimental values of relevant thermodynamic parameters. A general expression for the upper thermodynamical bounds on the initial heat source abundance at onset of inner core soldification is derived, which in the range of the published values of the thermodynamical parameter space yields upper bounds of 0.20 ± 0.15 wt% initial abundance of 40K, the most favoured radiogenic candidate in the inner core. Alternatively the expression can be used to set an upper limit to the age of the inner core given that we know the present abundance of heatsources and thermal parameters. E.g. assuming a heat transfer coefficient of k = 80 W m−1 K−1, a melting temperature of iron of 5500 K at the inner core boundary, and a value of the thermodynamical Grüneisen parameter of  γth,ICB = 1.5, it is found that if the core is older than 0.9 Gyr the inner core 40K abundance has to be lower than 0.142 wt% (the constraint set by cosmochemical arguments) and if the inner core is older than 2.52 Gyr the upper bound is less than 0.058 wt% (upper limit as set by high pressure experiments). Several geotherms for the inner core in subspaces of the parameter space are also presented. A comparison between the steady state and transient models is also performed, with the result that steady state models generally underestimates the temperatures and are not suitable for the inner core geotherm, mainly due to the transient nature of inner core formation and evolution. Finally the nickel-silicide/georeactor inner core model, as proposed by Herndon is investigated. It is found that this would generate a large molten region at the centre of the inner core, which has not been observed today. Hence it is concluded that a georeactor can not be operational at the centre of the Earth today.

ABSTRACT This study focuses on the dissolution and near-source attenuation of oxygenated gasoline hydrocarbons in groundwater from two gasoline residual sources: one containing gasoline with 9.8% methyl tert butyl alcohol (MTBE) and 0.2% tert-butyl alcohol (TBA) (GMT source) and the other containing gasoline with 10% ethanol (E10 source). The sources were injected into a shallow sand aquifer, leaving a residual plume to dissolve under natural gradient conditions. The MTBE plume (from the GMT source) and the ethanol plume (from the E10 source) were compared with predictions by the BIONAPL numerical model assuming ideal source dissolution and no biodegradation of the oxygenates or aromatic hydrocarbons. While the complete mass of injected MTBE appeared to pass row 2, little MTBE was found further downgradient. This mass loss was considered to be an artifact of the monitoring system and of possible biodegradation. The ethanol mass flux was better captured in the E10 gate. Essentially all the ethanol from the E10 source also passed row 2, but, the ethanol mass flux decreased somewhat from row 2 to row 4. The better mass recovery may reflect that the ethanol plume remained more in the center of the monitoring network as compared to the MTBE plume some of which may have bypassed the monitoring fence. MTBE, TBA, and ethanol in the model were assumed to dissolve at equilibrium. The MTBE and TBA concentration breakthrough curves are generally consistent with equilibrium dissolution. However, the mass flux values suggest non ideal dissolution. The ethanol concentration breakthrough curves and mass flux are consistent with equilibrium dissolution. Also, the observed concentrations were often higher than predicted at later times. These features could be due to non-equilibrium (kinetically-limited) dissolution However, non-ideal source conditions may have arisen due to most of the oxygenates being dissolved into the water injected along with the gasolines thus distributing the residual gasoline in a non-uniform manner. The concentrations of aromatics are higher than expected from the BIONAPL model and are consistent with tailing expected with non-equilibrium dissolution. However, the probable complexity of the source concentration distribution likely account for much of the concentrations variability. There were insufficient electron acceptors to support complete mineralization of either the oxygenates or the BTX-TMB compounds. Although, evidence of weak MTBE biodegradation was found, the major mass loss seemed to be related to the uncertainties in the monitoring network. Some ethanol mass loss could be attributed to fermentation to organic acids (which were not sought in the field experiment). The persistence of BTX-TMB through the gates seemed to be slightly greater in the presence of ethanol. The field study was also used to test the Ratio Mass Estimation (RME) method of estimating the initial NAPL mass in the source from downgradient contaminant concentrations. The method was found reasonably reliable if the downgradient concentrations were collected close to the source where biodegradation was minor.

The 1946 M7.3 Ancash earthquake triggered a large number of landslides in an epicentral area along the continental divide in the Andes of Peru. Reconnaissance reports by Silgado (1947, 1951), Heim (1949) and Rüegg (1950) published shortly after the earthquake describe some of the landslides, but lack any detailed documentation. A review of literature, field traverses, aerial photograph interpretation and GIS mapping, identified 45 landslides inferred to have been triggered by the event. The cumulative volume-frequency plot shows a strong power law relation, similar in form to that derived for landslides triggered by the 1994 Northridge earthquake (Harp and Jibson, 1995). Data for the Ancash earthquake plots near the regression line calculated by Keefer (1994), and modified by Malamud et al. (2004), for earthquake moment magnitude vs. total volume moved by landslides during the earthquake. A denudation (average surface lowering) of 76 mm and a denudation rate of 0.00585 mm/yr was estimated for the area over which the earthquake-triggered landslides occurred. Rock avalanches constituted 83% of the landslides which involved Cretaceous limestones interbedded with shales. Rock slope failures were common on slopes with a southwest aspect, an orientation corresponding to the regional dip direction of major planar structures in the epicentral area. In valleys oriented transverse to the NW-SE structural trend of the epicentral area, south-westerly dipping bedding planes combined with orthogonal joint sets to form numerous wedge failures. Three rock avalanches were analysed using conventional wedge failure criteria. Two of the rock avalanches which did not satisfy conventional criteria were utilized to develop a new criteria, i.e. stepped wedge criteria. Stepped wedge failure involves wedge movement along a stepped line of intersection formed by a nearly-vertical discontinuity, striking roughly parallel to the slope, and the conventional line of intersection formed by the bedding and orthogonal joint set. The nearly-vertical discontinuity forms the essential backscarp needed to facilitate stepped wedge failure. Additional characteristics of stepped wedge failure were also distinguished based on the wedge failures studied in the epicentral area of the 1946 Ancash earthquake.

Oxygen has been shown to be an effective addition of enhancing the bioremediation of petroleum hydrocarbon contamination in porous media; however, the ability to effectively deliver oxygen to petroleum hydrocarbon contaminated groundwater has proven difficult. A field and numerical modelling study was completed at a former gas station in southern Ontario, to assess the delivery of oxygen into groundwater in a fractured limestone aquifer that had been contaminated with petroleum hydrocarbons. A field investigation was completed to characterize the bedrock aquifer and the groundwater flow system. Several hydraulically active fracture zones were identified and characterized. To evaluate how dissolved oxygen would behave in this type of groundwater environment, an injection test was completed using iTi’s gPro® oxygen injection technology. About 1000 L of water containing dissolved oxygen at ~ 30 mg/L and a bromide tracer was injected over ~ 90 minutes and monitored for ~ 10 days in the injection well and in a multilevel monitoring well located 3 metres down-gradient. The oxygen concentration rose rapidly within the injection well and at two of the down-gradient monitor intervals which were aligned with the injection well via major fractures. Concentration tailing persisted in the injection well for several days following injection. The effects of biodegradation were not assessed as part of this investigation. A three-dimensional numerical model for groundwater flow and advective-dispersive transport within a discretely-fractured porous medium was calibrated to the field conditions. The simulated injection test demonstrated that oxygen rapidly filled the porous matrix surrounding the injection well and filled the local intersecting fractures. Following injection, the oxygenated groundwater in the local fractures was rapidly flushed by the natural groundwater flow, with oxygen arrivals appearing as sharp pulses in the fracture-associated breakthrough curves in the monitor well. Back diffusion of oxygen from the porous matrix into the injection well was accurately reproduced by the model. Media properties (fracture apertures, hydraulic gradient and hydraulic conductivity) were varied to assess the sensitivity of the model and to evaluate the effectiveness of the remediation technology under different conditions. The sensitivity runs demonstrated that the distribution of oxygen within the system could be significantly different with varying degrees of advective transport within the fractures and diffusion into the rock matrix which depends on the physical properties and hydrogeological conditions. Predictive simulations were then run with two different injection scenarios: a continuous injection for 1 week and a cyclic injection scenario (injection every 2 days). The same mass of oxygen was delivered in each simulation (~3 kg). The results demonstrated that the delivery of oxygen into the system (continuous or cyclic) could affect the advective transport of oxygen through the fractures and the diffusion of oxygen into the matrix. The continuous injection resulted in a maximum zone of influence (down-gradient and in the transverse direction) while maintaining high levels of oxygen within the matrix. On the other hand the cycle injection provided a more continuous supply of oxygen over time to the system. The zone of influence was reduced but diffusion into the matrix along the fractures increased, creating a more uniform zone of increased oxygen concentrations around the injection well and along the fractures. This study demonstrated that oxygen could effectively be delivered to a fractured bedrock system at levels potentially sufficient to enhance aerobic biodegradation. Additional areas requiring investigation include the behavior of oxygen during hydrocarbon biodegradation through field and modelling studies. Full scale implementation of the technology should then be considered to provide additional information with respect to the applicability of the technology to real world environments.