Etablierung und Untersuchung Diabetischer Schweine Transplantation isolierter Langerhansinseln Optimierung der Isolierungsergbnisse

During the 1950's and 1960's a railroad yard located in Oneida, Tennessee, was used as a creosote treatment facility for railroad ties. After the cross-ties were treated with creosote, the excess creosote was stored in an holding pond located about 100 feet north of Pine Creek (Fetterolf 1998). In 1990, during a creek modification project, creosote was discovered seeping through the banks of Pine Creek. The creosote had leached through the bottom of the pond and migrated towards the creek. In 1997, the Tennessee Department of Environment and Conservation authorized a remedial strategy prepared by Geraghty & Miller, Inc (Fetterolf 1998). The strategy involved the use of phytoremediation and a previously installed interception trench system. The primary goals of the phytoremediation plan are to stimulate biodegradation and to decrease groundwater flow, thus minimizing the migration of the contaminant into Pine Creek. Poplar trees were selected for the phytoremediation plan and were planted in two sections. The objectives of this report involved analyzing the hydrogeology of the Oneida, Tennessee site and organizing the collected data for the purpose of evaluating the impact of the phytoremediation and interception trench systems on the aquifer. The water level data was used to evaluate water level and hydraulic gradient changes due to evapotranspiration, rainfall, and groundwater extraction. It was obvious from the water level and rainfall comparison plots that the rainfall has a measurable effect on the water table elevation (i.e. groundwater flow). Some areas may be less affected because the coal layer has a tendency to decrease recharge. Meanwhile, the interception trench lowers the water level around the trench. The decrease in head occurs before and after the trench, thus the water level forms a "v-shape" at the trench. This "v-shape" lends to the notion that the hydraulic gradient also slopes towards the trench in both directions. As for the phytoremediation, there was not sufficient evidence to suggest that the water levels were being lowered by evapotranspiration. This was expected since the poplar trees were had only completed their second growing season. GMS MODFLOW was used to predict the effects on the water table due to the phytoremediation and the interception trench systems. The calibrated model did an adequate job in simulating the site when the interception trench was not in operation and the trees were not in their growing season. By using variable recharge in some areas, the results are expected to improve. For example, it is important to know the location of the coal layer so this area can be given a lower recharge value than the other areas in the model. As for the trench model, the simulated heads were much lower than the observed heads, which emphasizes that using wells is not the best method to simulate the interception trench. In the future, a transient model should be used to simulate the site with the trench operation, and the drain package could be used to model the trench itself. Meanwhile, the ET model was a valuable simulation, because it illustrates how effective the poplar trees can be even under conservative conditions. With an assumed root zone of just 3 feet and a maximum potential evapotranspiration rate of 4.6 gallons per day per tree, the majority of the site will experience the dry conditions expected. / Master of Science

<p>Continuous improvement is one of five principles in General Motors – Global Manufacturing System (GM-GMS). GM-GMS has been used by Saab Automobile AB since 2003 and is a central component for realisation of GM’s vision. Internal audits have discovered problems with one of the tools, practical problem solving (PPS), which needs to be improved. The department manufacturing of press and body (PK) wants to survey the problems and initiate a process of improvement. The purpose of this thesis work is to develop a foundation for future re-designs of the PPS process. Employees have been interviewed and observed in order to explore possible difference theoretical and practical problem solving with PPS. The result of the investigation shows 4 different and interrelated problem categories. 1. Information transfer, PPS hand over to product quality engineers (PQE) department cause problem when general assemblies (GA) are excluded from the improvement work. General assemblies do not get any feedback information from (PQE) about planed countermeasures. 2. Problem solving, team leaders has difficulties with identifying the true problem. Using “five-why” during the analysis work causes problem, since team leaders do not have the knowledge of how to use the tool in a proper way. 3. Documentation of PPS, the content in the PPS-form is a problem according to team leaders. Lack of knowledge and understanding of how to use the PPS-document leads to incomplete and incorrect analysis. 4. Coordination of involved people, support and help are missing from the management and quality engineer according team leaders. PPS from Global Costumer Audit are imposing time stress according to team leaders. Recommendations for further work is to investigate the opportunities with a web based PPS and process to improve information transfer and documentation of PPS. A second recommendation is to train and coach team leaders in problem solving and improve coordination of involved people and skills in problem solving.</p>

Continuous improvement is one of five principles in General Motors – Global Manufacturing System (GM-GMS). GM-GMS has been used by Saab Automobile AB since 2003 and is a central component for realisation of GM’s vision. Internal audits have discovered problems with one of the tools, practical problem solving (PPS), which needs to be improved. The department manufacturing of press and body (PK) wants to survey the problems and initiate a process of improvement. The purpose of this thesis work is to develop a foundation for future re-designs of the PPS process. Employees have been interviewed and observed in order to explore possible difference theoretical and practical problem solving with PPS. The result of the investigation shows 4 different and interrelated problem categories. 1. Information transfer, PPS hand over to product quality engineers (PQE) department cause problem when general assemblies (GA) are excluded from the improvement work. General assemblies do not get any feedback information from (PQE) about planed countermeasures. 2. Problem solving, team leaders has difficulties with identifying the true problem. Using “five-why” during the analysis work causes problem, since team leaders do not have the knowledge of how to use the tool in a proper way. 3. Documentation of PPS, the content in the PPS-form is a problem according to team leaders. Lack of knowledge and understanding of how to use the PPS-document leads to incomplete and incorrect analysis. 4. Coordination of involved people, support and help are missing from the management and quality engineer according team leaders. PPS from Global Costumer Audit are imposing time stress according to team leaders. Recommendations for further work is to investigate the opportunities with a web based PPS and process to improve information transfer and documentation of PPS. A second recommendation is to train and coach team leaders in problem solving and improve coordination of involved people and skills in problem solving.

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Groundwater is one of the main sources of drinking water in Sweden. Groundwater fluctuations and the detection of flow direction is of significant environmental importance especially when there is a risk for transport of contaminations. The Swedish Nuclear Fuel and Waste Management Company (SKB) has done detailed geotechnical investigations at two potential sites for a final nuclear waste deposition. This report presents the results from groundwater modeling in quaternary deposits in one of these sites. A steady state three dimensional groundwater model was developed for a 71 km2 large area in the Laxemar-Simpevarp, 320 km south of Stockholm close to the nuclear power plant Simpevarp. For this purpose, the Groundwater Modelling System (GMS) was used. The model uses finite difference method to solve the partial differential equation for the water movement with constant density through porous medium. The main objectives were to predict the groundwater heads and the flow directions, and to study the water balance. A conceptual model approach was used by creating five heterogynous soil and rock layers. GIS (Geographic Information System) was used to create top and bottom elevation of the layers by interpolating the GIS data. The model was calibrated using observation data in groundwater monitoring wells and the optimum values for recharge and hydraulic values were found. The numerical simulation was done for two different grid sizes (511×316 m2 and 255×158 m2) referred to coarse and fine grid model respectively. Results from the multilayer model showed flow towards the sea and in the quaternary deposits but not in high elevated rocks. The water balance in the multilayer model was satisfied in both grid sizes. The 3D groundwater model GMS was successfully applied to the large Laxemar-Simpevarp region. The choice of grid size was studied and better agreements between observed and simulated groundwater heads were found in the finer grid model. Large simulation errors in some of the observation wells can indicate GMS model’s weakness in modelling thin soil layers and large variance in topography.

A groundwater model of a 126.2-acre ranch in Cambria, California was expanded upon to analyze the effects of artificial recharge and a subsurface barrier. The ranch lies within the 48mi2 Santa Rosa Creek Watershed along the Central Coast of California. The mainly agricultural watershed outfalls to the Pacific Ocean to its west. Creek Lands Conservation, a non-profit that aims to conserve and restore habitat along the Central Coast, plans to identify projects to restore stream flow during dry seasons in the creek that runs through the Santa Rosa Creek Watershed and to increase artificial groundwater recharge. This study focuses on two of those projects. One project is an existing recharge basin and the other is a subsurface barrier. The objective of this numerical model is to improve upon an existing model by using a longer duration of data to calibrate the model, calibrating the model to hydraulic properties of soil samples that were obtained from the site at various depths, refining elevations of layers through integration of new borehole exploration data, and adding updated and new data such as mountain front recharge and pumping rates. The modeling program used was GMS which allows calculation and determination of heads and flow directions. Within the model, there are three separate layers based on hydrogeological characterization from previous studies. There is an upper unconfined zone, a confining clay layer, and a confined zone. A package within GMS (Groundwater Modeling System) called PEST (i.e., Parameter ESTimation) was used to calibrate the model to known water surface elevations throughout the site. Data such as elevations, head boundaries, stream flow, pumping rates, recharge, evapotranspiration, well locations, and hydraulic properties of the subsurface was processed and incorporated into the overall model in GMS. Recharge rates from the basin were estimated to be 0.1 m/day roughly starting in February and ending in May for each year. The model showed that the confining layer slows down the flow of water from the recharge basin, but it does eventually percolate into the underlying groundwater aquifer before reaching Santa Rosa Creek after a time period of 5 years. The proposed subsurface barrier does reduce travel times of groundwater by roughly a year and helps percolation of water into the confined layer. With the subsurface barrier it was seen that the water held within the confined aquifer increased on average 5,200 m3 each year.

There are many methods for cleaning up contaminated soil and groundwater. Phytoremediation is an engineered method that utilizes plants and trees to remove or immobilize inorganic and organic contaminants. The plants and trees can contain contaminant plumes, uptake the contaminants, or aid in the degradation of the contaminants through several poorly understood mechanisms. Hybrid poplar trees were planted to contain a creosote contaminant plume at the study-site in Oneida, Tennessee. This research looks at how the trees will affect groundwater flow in the site. This is accomplished with the groundwater modeling program MODFLOW. The trees are simulated using the Evapotranspiration Package within MODFLOW, within the GMS modeling platform, to produce a two-dimensional unconfined aquifer viewpoint groundwater model. Site characterization, setup, and rationale are provided. The modeling methodology including calibration, sensitivity analysis, non-unique solution check, and verification are also provided. The modeling methodology included steady-state model calibration at the study-site to match observed field data; precursory steady-state and subsequent practice transient calibrations at the site; and incorporation of the simulation of evapotranspiration in the final transient model calibrations at the site. The results show that a phytoremediation system consisting of densely-planted hybrid poplar trees can indeed impact groundwater flow, although not to the extent that clearly would contain a creosote contaminant plume. Various input parameters including specific yield, transient recharge, starting heads, evapotranspiration rates, and evapotranspiration extinction depths impacted MODFLOW model sensitivity in transient calibrations. Varying the time steps in post-precipitation stress periods did not significantly impact the model output. The interception trench conductance played a minimal role in the calibration, but trench groundwater collection data was lacking, and the trench was frequently in need of maintenance. Further suggested data requirements include more frequently collected rainfall and piezometer data, as well as the installation of more piezometers outside the model domain contained in this study. Using the Evapotranspiration Package in MODFLOW provided more realistic and authentic results than using the Well Package (used in a previous study of the site by Panhorst in 2000) to simulate evapotranspiration. The Evapotranspiration Package in MODFLOW incorporates transpiration extinction depths that prevent transpiration when the water table drops below a certain depth. Further suggested program development includes incorporating an asymptotic function for transpiration rates and allowing the Evapotranspiration Package to import evapotranspiration rates, extinction depths, and elevations. It may be deduced from this impact of flow that the tree system will aid in containment of a contaminant plume, but at the trees current growth stage, and with the coal layer present at the site, the containment is limited. / Master of Science

Loddby sulfitmassabruk var under sin verksamhetstid beläget vid Loddbyviken, cirka fem kilometer norr om Norrköping. På bruket bedrevs tillverkning av sulfitmassa mellan år 1899 och 1977 inom ett område som omfattar 18,6 hektar. Det före detta sulfitmassabruket anses idag vara förorenat till den grad att det medför en mycket stor risk för människors hälsa och miljön, men för att kunna besluta om åtgärder gällande den förorenade marken vid Loddby f.d. sulfitmassabruk behöver bland annat de hydrogeologiska förhållandena inom området klargöras. Detta examensarbete syftade till att kartlägga grundvattenströmningen vid Loddby f.d. sulfitmassabruk genom att utveckla en platsspecifik grundvattenmodell med modellkoden MODFLOW i programvaran Groundwater Modeling System (GMS). Dessutom avsåg examensarbetet att undersöka hur grundvattenströmningen i området påverkas av fluktuationer i den intilliggande Loddbyvikens vattennivå. Initialt utvecklades en konceptuell modell för området, där det hydrologiska systemet förenklat beskrevs med avseende på områdets geologi, hydrologi och klimat. Modellområdet avgränsades utefter topografiska vattendelare samt hydrologiska gränser och delades sedan vertikalt in i tre lager utefter de huvudsakliga jordmaterial som hade identifierats vid undersökningar i området: fyllnadsmaterial, lera och morän. I GMS delades modellområdet sedan in i ett rutnät med storleken 5x5 meter och dess ränder tilldelades lämpliga randvillkor. Genom att interpolera utsträckningen av modellens tre lager från sonderingspunkter med känd geologi kunde den konceptuella modellen beskrivas matematiskt i programvaran. För att öka modellens tillförlitlighet kalibrerades jordmaterialens hydrauliska konduktiviteter mot observerade grundvattennivåer i flertalet grundvattenrör inom Loddby f.d. sulfitmassabruk. Efter kalibrering var fyllnadsmaterialets, lerans samt moränens hydrauliska konduktivitet 2,1ˑ10-4 m/s, 5,7ˑ10-7 m/s respektive 3,9ˑ10-5 m/s. En känslighetsanalys utfördes slutligen för att undersöka hur valet av värden på jordmaterialens hydrauliska konduktiviteter samt grundvattenbildningen påverkar modellresultaten. Simuleringarna med den kalibrerade modellen visade bland annat att grundvattnet generellt rör sig från områdets västra delar mot Pjältån och Loddbyviken i norr och öster, dock runt de områden där bergytan når höga nivåer. Förändringar i Loddbyvikens vattennivå visade sig ha en viss påverkan på mängden vatten i systemet, men bedömdes inte medföra en större effekt på strömningsmönstret i området. Känslighetsanalysen visade att modellen var mycket känslig för värdet på grundvattenbildningen, samt att även den hydrauliska konduktiviteten för moränen hade en stor effekt på resultatet. Ett lågt värde på lerans genomsläpplighet visade sig kunna leda till modelleringssvårigheter och fyllnadsmaterialets konduktivitet hade generellt en liten påverkan på resultatet. / Loddby sulphite pulp factory was during its active days located next to Loddbyviken, approximately five kilometers north of Norrköping. Production of sulphite paper pulp was conducted between the years 1899 and 1977 within an area of 18,6 hectares. The former sulphite pulp factory is today considered polluted to the extent that it is entailing a great risk for human health and the environment, but to be able to decide what measures to take, the hydrogeological conditions in the area need to be clarified. The objective of this master’s thesis was to map the groundwater flow pattern within Loddby former sulphite pulp factory by developing a site-specific groundwater model with the groundwater flow model MODFLOW in the software Groundwater Modeling System (GMS). The master’s thesis also aimed at examining how the groundwater movement in the area is affected by fluctuations in the water level of Loddbyviken. A conceptual model was initially created to describe the hydrological system in a simplified way with regards to the geology, hydrology and climate within the area. The model domain was delimited by topographical water divides and hydrological boundaries, and was thereafter divided into three horizontal layers based on the main materials that have been identified during investigations within the area: filling material, clay and till. In GMS, the model domain was divided into a 5x5 meter grid and its borders were assigned appropriate boundary conditions. By interpolating the three model layers from scatter point data of known geology, the conceptual model could be described mathematically within the software. To increase the reliability of the model, the hydraulic conductivities of the materials were then calibrated against observed hydraulic head in several groundwater monitoring wells in the area. After the calibration, the hydraulic conductivities of the filling material, clay and till were 2,1ˑ10-4 m/s, 5,7ˑ10-7 m/s and 3,9ˑ10-5 m/s respectively. A sensitivity analysis was then performed in order to examine how the values of hydraulic conductivity and groundwater recharge would affect the model results. Simulations with the calibrated model showed that the groundwater generally moves from the western parts of the area towards Pjältån and Loddbyviken in the north and east. However, it moves around the areas where the impermeable bedrock is close to the ground surface. Changes in the water level of Loddbyviken proved to have some effect on the amount of water in the system, but they did not entail a greater influence on the groundwater movement pathways in the area. The sensitivity analysis showed that the model was very sensitive regarding the groundwater recharge and the hydraulic conductivity for the till. A very low conductivity of clay turned out to lead to some modeling difficulties and the conductivity of the filling material showed to only have a small effect on the result.

Håbo municipality is looking for alternative drinking water sources for its residence city of Bålsta. One possible source is the Vreta-Bålsta esker located northeast of Bålsta, which could be used for artificial infiltration and extraction of groundwater. Located on this esker is an area called Dragets industrial area, in which several objects of potential contamination have been identified. One of these is a Landfill located in the northern part of the industrial area in which the local fire fighting forces has used this area for training exercises. During these exercises they have used aqueous film forming foams (AFFFs) containing Per- and polyfluoroalkyl substances (PFAS). Some PFASs have demonstrated adverse health effects already at low concentrations and no more than 90ng l-1 is recommended in Swedish drinking water. In order to assess the suitability of the esker as a source for drinking water a model of the esker was created inside the program GMS (Groundwater modeling system). In GMS the package MODFLOW was used to create a groundwater flow model, and the package MT3DMS was used for contamination transport of PFAS from the landfill. The finished model showed a groundwater divide located in the central parts of Dragets industrial area, with the water either running south toward Lake Mälaren or north towards Lilla Ullfjärden. In total three different PFAS species were used in the transport model with the abbreviations PFOS, PFPeA and PFBA. The transport model was created as a point source to see the transport behavior of PFAS from the landfill. This showed that all the contamination transport that occurred would transport the PFAS north towards Lilla Ullfjärden. Based on this result this would mean that a use for artificial infiltration and extraction of groundwater in the southern part of the esker would not pose a contamination risk from the landfill.