MESHWR / Department of Hydrology and Water Resources / See the attached abstract below

This study tested a dynamic modelling approach based on salt application, meteorological data and generic descriptions of hydrogeological environments for describing the spread of deicing salt to the surroundings and the corresponding increase in chloride storage in soil. Both the amount of chloride storage and the annual variation pattern were significantly altered due to deicing salt application and spread to the roadside environment. Data from field investigations comprising different hydrogeological environments and different methods of measurement were used to examine the variability of the salt deposition pattern in the vicinity of the road, and to test the performance of the model with respect to different soils and vegetation types. The use of typical hydrogeological environments to represent inputs to the model was shown to be useful to demonstrate the importance of soils, vegetation type and groundwater conditions for modelling the impact of deicing salt on soil water and the response to environmental changes in the vadose zone. However, the use of hydrogeological environment could also be misleading in view of the high degree of variability at the field scale. The different methods of measurements and simulations represented different spatial and temporal scales that were shown to be complementary useful to quantify the different pathways of deicing salt in the roadside environment. Continuous simulations complemented with selected field monitoring should therefore be promoted. / QC 20100526

The Carpathian foredeep is a lengthwise depressed area in the Carpathian foreland. In Moravia, it is mainly filled with Neogene soils. The thesis focuses on the South Moravian landslides which occurred in shallow relicts of Neogene deposits along a foredeep margin which lie on the rocks of the Bohemian Massif. Landslide activity within these shallow basins is a result of a number of factors. In the theoretical part, important general features of landslide areas, their geological conditions and hydrogeological regime are investigated. Next, available data on the geomechanical behaviour of soils, often connected with these landslides, are summarized and evaluated. The case studies deal with the landslide localities Budkovice-Svízla, Brno-Bystrc and Znojmo. The case study of Budkovice-Svízla is based on an extensive engineering geological survey of the locality and the measurement of groundwater levels in the years 1988 – 2017. In the thesis, the hydrogeological regime of the area is analysed and a reconstruction of the ground surface before slope movement is carried out. The probable trigger mechanisms, the development of sliding and the efficiency of the executed remedies of the landslide are evaluated by numerical studies. In conclusion, general recommendations for an engineering-geological survey and building activities in the area of interest are formulated.

Indiana University-Purdue University Indianapolis (IUPUI) / ABSTRACT Dustin Graves ASSESSING THE ROLE OF GEOLOGIC SETTING ON THE HYDROLOGY AND GROUND WATER GEOCHEMISTRY OF FENS IN THE GLACIATED MIDWESTERN UNITED STATES A water quality investigation of several fens located in the temperate glaciated Midwestern United States, near the southern limit of fen occurrence, was conducted to assess the role of geologic setting on the hydrogeochemical signature of fens and to compare hydrogeochemistry of fens located in different geographic and geologic settings. The five studied fens, located in the Central Till Plain physiographic region of Indiana, receive ground water sourced from glacial tills with very similar petrologic composition. These wetlands are hydrogeomorphically classified as slope wetlands with dominant ground water input. More specifically, these sites are inter-till / intra-till type fens (Type Ia and Ib) or outwash terrace type fens (Type II). Shallow ground water was collected just prior to surface interception (source water), and again after discharging into each fen (fen water) and measured for a suite of cations (Ca2+, Mg2+, K+, Na+) and anions (HCO3- SO42-, NO3-, NO2-, PO43-, and Cl-). Fen water hydroperiods showed similar dynamics, despite some variation in the hydrologic input of these systems (source water). Central Indiana fens are recognized as Ca2+, Mg2+, and HCO3- dominated systems. Fen water showed substantial evolution from source water at each study site, evidently the result of carbonate and gypsum dissolution dynamics. However, when only fen water is analyzed, results suggest that ground water of the southern fens represents geochemical similarity, with the exception of anthropogenic influence. The greatest geochemical variation among central Indiana fens can be attributed to Na+ and Cl-, which has been linked to road salt contamination at two of the study sites. This hydrogeochemical study also reveals that fens (slope wetlands) within this particular geologic setting of central Indiana show strong geochemical similarities to fens located throughout the temperate Northern Hemisphere. However, statistical analyses provide evidence that the parameters of Ca2+, HCO3-, and SO42- account for the greatest variation among these wetland communities, suggesting that calcium carbonate and gypsum dissolution dynamics are primarily fen specific while other parameters remain relatively homogenous across a wide geographical range. Lenore P. Tedesco, Ph. D.

In addition to a loss of potential revenues from Utah's $393 million sport fishing industry, the state expends millions of dollars every year on costs associated with whirling disease mitigation and prevention. A state fish hatchery at Midway, Utah was closed when the shallow unconfined aquifer being used for fish culture by spring discharge was deemed to be contaminated by whirling disease. An alternative water source may exist in a confined aquifer below this contaminated unconfined aquifer. However, the complex hydrostratigraphy presents a challenge in determining if this source is a viable resource for fish culture. Geological, physical, chemical, geophysical, and isotopic data were combined to create a conceptual model of the groundwater flow at the site and to determine the interactions this confined aquifer may have with the contaminated aquifer. This model divides groundwater at the hatchery into a shallow unconfined system, an upper confined system, and a lower confined system. The shallow unconfined system is characterized by a water table ~1m below ground surface, several active springs, fast travel times, modern water mixed with ancient hydrothermal water, relatively high TDS, and relatively enriched isotopic values. The confined aquifers have a smaller hydrothermal component, relatively depleted isotopic values, lower TDS, and modern recharge components. Two orthogonal shallow high-resolution seismic reflection profiles indicate substantial heterogeneity in the subsurface at the level of the confined systems at the hatchery. Several north-south trending normal discontinuities were interpreted as possible faults from the seismic profile oriented as a dip line, whereas the strike profile shows discontinuous layering without noticeable faulting. A well log profile for the site shows discontinuous tufa layers amid heterogeneous alluvium material. These tufa layers separate upward leaking confined aquifers from the unconfined system. It is only through the integration of several methods that such mixed systems, can be understood. In this study, the lower confined aquifer was found to be a sufficient and safe resource through the integration of numerous methods.

Summary: This master's thesis focuses on the actualization and compiling of a detailed engineering geological map in scale 1 : 5 000. The thesis deals with the area defined by four points in the coordinate system JTSK - Křovák: : x1= -749 300, y1= -1 043 400; x2= -745 900, y2= -1 043 400; x3= -749 300, y3= -1 044 500; x4= -745 900, y4= -1 044 500. In the first background research part, the geomorphologic, climatic, geologic, hydrogeological and geodynamic conditions of the mapped area are presented. The second practical part of the thesis consists of four major parts: the engineering geological conditions map, the height of recent sediments map, the hydrogeological map and the map of documentation points. Further, the master's thesis contains geological cross-section. The actualization of engineering geological condition map provides new information about recent sedimentation areas and anthropogenic sediments, especially about landfills and landslides.

Summary: This master's thesis focuses on the actualization and compiling of a detailed engineering geological map in scale 1 : 5 000. The thesis deals with the area defined by four points in the coordinate system JTSK - Křovák: : x1= -749 300, y1= -1 043 400; x2= -745 900, y2= -1 043 400; x3= -749 300, y3= -1 044 500; x4= -745 900, y4= -1 044 500. In the first background research part, the geomorphologic, climatic, geologic, hydrogeological and geodynamic conditions of the mapped area are presented. The second practical part of the thesis consists of four major parts: the engineering geological conditions map, the height of recent sediments map, the hydrogeological map and the map of documentation points. Further, the master's thesis contains geological cross-section. The actualization of engineering geological condition map provides new information about recent sedimentation areas and anthropogenic sediments, especially about landfills and landslides.

Die Arbeit beinhalted verschiedene Studien, die die Grundwasser (GW)-Oberflächenwasser (OW)-Interaktion im Norddeutschen Tiefland untersuchen. Dabei werden zwei Ansätze verfolgt: der hydrogeologische und der limnologische Ansatz. Ersterer betrachtet die Interaktionen aus dem Blickpunkt der unterirdischen Wasserbewegung. Diese ist hauptsächlich gesteuert durch die Verteilung der hydraulische Leitfähigkeit (Sediment) und des hydraulischen Gradienten. Es ist immer noch eine Herausforderung beide Steuerungsgrößen richtig abzuschätzen. Mit neuen Ansätzen, welche auf der Wechselwirkung zwischen verschiedenen Landschafskomponenten basieren (Wasserstände, Topographie, Vegetation, Nährstoffe), wurde klein- bis mesoskalige Sedimentverteilungen in einer Aue untersucht und beschrieben. Des Weiteren konnte mit einem einfachen Grundwassermodell gezeigt werden, das verschiedene Grundwasserstonckwerke (regionale Skala) die Interaktion zwischen GW und einem See beeinflussen können. Der limnologische Ansatz basiert auf der Annahme, dass Bereiche in einem See identifiziert werden können an denen Grundwasser zutritt. In der vorliegenden Arbeit, wurden eine Methode getestet, die auf der unterschiedlichen Temperatur von beiden Wasserkörpern basiert: Im Frühjahr ist das GW wärmer als das Seewasser und sollte sich an der Seeoberfläche einschichten. Mittels thermalen Luftbildaufnahmen sollten somit Grundwasserzutritte identifizierbar sein. Die Studien aber zeigten, dass dies nur unter bestimmten Voraussetzungen möglich ist und seeinterne Prozesse bei der Interpretation der Temperaturverteilung an der Seeoberfläche berücksichtigt werden müssen. Somit besteht noch ein erhöhter Forschungsbedarf bezüglich des limnologischen Ansatzes. Dennoch birgt dieser ein großes Potential, denn er eröffnet die Möglichkeit kurzfristig auf grundwasserbürtige Einträge in OW direkt an der Sediment-Wasser-Grenze zu reagieren und verschafft somit Zeit für aufwändigere hydrogeologische Untersuchungen. / The thesis constists of different studies, which are investigating groundwater-surface water interaction in North-German-Lowlands. Therefore, two different approaches were used: the hydrogeological and the limnological one. The former is based on the classical hydrogeological point of view: the subsurface water movement is mainly driven by hydraulic conductivity (sediment) and the hydraulic gradient. However, the characterisation of both is still a challange. Different methods were used to characterize small- and meso-scale sediment distributions within a lowland floodplain. These are based on the interactions of different landscape components (water level fluctuations, topography, vegetation, nutrient distributions). Furthermore, a simple groundwater model was set up to illustrate how regional groundwater flow impacts local groundwater-lake interactions. The limnological approach is based on the assumption that areas of groundwater exfiltration into a lake are detectable directly at the sediment-water interface. For this purpuse, it was assuemed that temperature differences between both water bodies could be used as follows: in spring the groundwater temperature is higher than that of lakes. Hence, the warmer groundwater float on the lake surface. That should be detectable by thermal infrared imaging. However, the studies could illustrate, that this is only true for specific conditions. Furthermore, lake internal processes need to be considered for interpreting temperature distributions at the lake surface. As a consequence, the limnological approach requires more research activities, since it gives the opportunity to initate short-term measures on groundwater inputs in surface waters. This would also guarantee larger time spans for time-consuming hydrogeological studies.

The Sandspruit River catchment, found within the heart of the Swartland region is infamous for wheat and wine production. Variable groundwater quality and low productivity is encountered within the folded and fractured Malmesbury Group aquifer, whilst the most productive and better quality groundwater is found within the Table Mountain Group sandstone. The Sandspruit catchment (a tributary of the Berg River) represents a drainage system, whereby saline groundwater with TDS up to 10870 mg/l, and EC up to 2140 mS/m has been documented. The catchment belongs to the winter rainfall region with precipitation seldom exceeding 400mm/yr, as such, groundwater recharge occurs predominantly from May to August. Recharge estimation using the catchment water-balance method, chloride mass balance method, and qualified guesses produced recharge rates between 8-70 mm/yr. To understand the origin, occurrence and dynamics of the saline groundwater, a coupled analysis of major ion hydrochemistry and environmental isotopes (δ¹⁸O, δ²H and ³H) data supported by conventional hydrogeological information has been undertaken. Research data were collected in three seasonal field sampling campaigns within the study catchment. These spatial and multi-temporal hydrochemical and environmental isotope data provided insight into the origin, mechanisms and spatial evolution of the groundwater salinity. These data also illustrate that the saline groundwater within the catchment can be attributed to the combined effects of evaporation, salt dissolution, and groundwater mixing. The geology together with the local and regional faults control the chemistry of the groundwater, whereby relatively fresh groundwater can be observed in certain direct recharge areas. The salinity of the groundwater tends to vary seasonally and evolves in the direction of groundwater flow. The stable isotope signatures further indicate two possible mechanisms of recharge; namely, (1) a slow diffuse type modern recharge through a relatively low permeability material as explained by heavy isotope signal and (2) a relatively quick recharge prior to evaporation from a distant high altitude source as explained by the relatively depleted isotopic signal and sub-modern to old tritium values. A conceptual hydrogeological model based on the hydrogeological, hydrochemical, and environmental isotope data was developed for the Sandspruit catchment. This model, together with statistical and groundwater quality analysis has lead to the development of a proposed local optimized monitoring scheme for the catchment. / Thesis (M.Sc.)-University of KwaZulu-Natal, Westville, 2012.

In komplexen Grundwasserleitern lassen sich grundlegende Informationen zur Abgrenzung von Quelleinzugsgebieten, zur Ableitung von Grundwasserfließrichtungen oder zur Bewertung der Vulnerabilität nicht allein über konventionelle hydrogeologische Methoden (beispielsweise Grundwassergleichenpläne, Quellschüttungsmessungen, Pumpversuche) gewinnen, so dass vielfach ergänzend hydrochemische Methoden eingesetzt werden. Zu den gängigen hydrochemischen Methoden gehören Auswertungen der Hauptionenverhältnisse, stabiler und radioaktiver Isotope, von Umwelttracern und Metallen der Seltenen Erden einschließlich des Yttriums sowie der aktive Einsatz künstlicher Markierungsstoffe. Die Anwendung gängiger hydrochemischer Methoden ist durch natürliche oder anthropogene Hintergrundkonzentrationen, die die Ausbildung eines ausreichenden Kontrasts behindern können, limitiert. Da diese Methoden meist nur an der Quelle als integrales Signal des gesamten Einzugsgebiets ansetzen, kann die Abgrenzung des Einzugsgebiets nur indirekt durch die Abschätzung von Volumina und darauf aufbauender Abschätzung der Flächengröße vorgenommen werden. Zur konkreten Lokalisierung der Einzugsgebietsgrenzen und der Ableitung von Grundwasserfließrichtungen sind also zusätzliche Informationen notwendig. Durch die menschliche Produktion organischer Verbindungen steht ein riesiges Spektrum potentieller Indikatoren zur Verfügung, das die Anzahl der bei etablierten Methoden eingesetzten Stoffe um ein Vielfaches übertrifft. Aufgrund ihrer rein anthropogenen Herkunft haben organische Spurenstoffe keine natürlichen Hintergrundkonzentrationen und sind daher bereits auf einem sehr geringen Konzentrationsniveau nutzbar. Im Gebiet der „Waldecker Scholle“ konnten sowohl die räumliche Verteilung organischer Spurenstoffe als auch deren saisonale Konzentrationsschwankungen in einem komplexen Grundwassersystem mit moderat verkarsteten Grundwasserleitern untersucht werden. Die auftretenden Stoffmuster reflektieren die hydrogeologischen Verhältnisse und können zur Lokalisierung von Quelleinzugsgebietsgrenzen genutzt werden. Weitere Hinweise liefern die organischen Spurenstoffe zur Identifikation von punktuellen Eintragsquellen und zur Ausbreitung der aus Punktquellen freigesetzten Stoffe im Grundwasserleiter sowie zum Attenuationspotential dieser Stoffe. Weiterhin kann die hydraulische Wirksamkeit von geringleitenden Zwischenschichten und Störungszonen mittels Identifikation einer Fließkomponente mit einer Verweilzeit von mehr als 20 Jahren abgeschätzt werden. Auch Annahmen hinsichtlich der Vulnerabilität lassen sich validieren. Der Vergleich mit dem hydrogeologisch gut untersuchten Einzugsgebiet der Gallusquelle, zeigt, dass Stoffgruppen wie Triazine und Triazole eine weite Verbreitung haben, andere Stoffe jedoch an bestimmte Gegebenheiten im Gebiet gebunden sind (beispielsweise Altablagerungen, Kanalsystem). Außerdem bestätigt sich in beiden Gebieten, dass das Auftreten von Stoffen sowohl von den Stoffeigenschaften als auch von den hydrogeologischen Eigenschaften abhängig ist. Das bedeutet, dass die Art der in einer Karstquelle auftretenden Stoffe selbst ohne aufwändige zeitlich hochaufgelöste Beprobung bereits Rückschlüsse auf Systemeigenschaften zulässt. Die vorliegende Arbeit zeigt somit, dass organische Spurenstoffe bereits auf der Untersuchungsebene des konzeptionellen Modells wertvolle Indikatoren zur Charakterisierung komplexer Grundwassersysteme sein können. Die große Menge an zur Verfügung stehenden Stoffen bietet die Möglichkeit, bestimmte Stoffe auszuwählen, die die jeweiligen Systemcharakteristika widerspiegeln. Mit organischen Spurenstoffen können sowohl Grundwasserkomponenten unterschiedlicher Verweilzeiten von wenigen Tagen bis zu mehreren Jahrzehnten identifiziert werden als auch räumliche Zusammenhänge von wenigen Metern bis über Einzugsgebietsgrenzen hinaus untersucht werden. Die Einbeziehung organischer Spurenstoffe in die Erkundungsstrategien komplexer Grundwassersysteme hat daher ein vielversprechendes zukunftsweisendes Potential.