Thesis (M.S.)--University of Hawaii at Manoa, 2006. / Includes bibliographical references (leaves 105-109). / ix, 109 leaves, bound col. ill., col. maps 29 cm

Degradation of streams in urban-rural fringe regions occurs through complex interactions between hydrological, physical, chemical and biological mechanisms of the stream environment and surrounding landscape. Biological monitoring using macroinvertebrates may capture the complex and cumulative influences of land activity on the stream environment. The Salmon River catchment in the township of Langley, British Columbia, Canada straddles urban and rural environments in the Lower Fraser Valley. To date the Salmon River catchment has been subject to several environmental surveys. Following these earlier investigations, this study quantified relationships between the stream environment and changing land activity, across multiple scales, from 1975 to 2005, using macroinvertebrates as environmental integrators. Current and historical water, sediment, and macroinvertebrate information along with land use and land-cover evaluations were used to quantify relationships between the macroinvertebrate community and land activity in the catchment. Spatial and seasonal results for specific conductivity (a total dissolved ion indicator) and NO₃⁻-N and PO₄³ (nutrient indicators) traced groundwater and overland inputs to the stream environment. Nitrate guideline exceedances occurred at groundwater-influenced sites. Elevated sediment trace metal concentrations and Zn guideline exceedances occurred mid-reach in the catchment. Peak total macroinvertebrate and sensitive taxa abundance occurred mid-reach in the catchment in 2005, while richness and proportional sensitive abundance peaks were seen at groundwater-influenced sites. The dominance of tolerant to moderately pollution tolerant taxa occurred throughout. Despite historical water quality concerns at groundwater-influenced sites, greater shifts in community composition occurred in headwaters regions. Patterns of land use and land cover changed in sensitive areas (i.e. above aquifer and in the headwaters). A greater number of correlations between land activity and macroinvertebrate measures occurred at streams sites with 100 m buffers. The abundance of sensitive taxa positively correlated with the amount of agricultural land use, while rarefaction declined. Several Macroinvertebrate functional feeding groups correlated positively to forest cover, while sensitive taxa abundance and Zn concentrations declined. Results suggest continued water quality and sediment trace metal concerns, while macroinvertebrate results point to nutrient enrichment and greater historical variability in headwaters regions. Agricultural activity appears to have a stronger influence on aspects of the stream environment despite the presence of urban-rural land activity.

Sedimentary deposits are important aquifers in many parts of the world and in order to explore, develop and manage these aquifers, it is necessary to determine the relationship between the hydrogeologic properties and sedimentary facies (aquifer characterization). Within a sedimentary hydrogeologic system, the environment of deposition and the resulting distribution of grain sizes, texture, and facies associations within different individual aquifer bodies influence variations in hydraulic properties. Successful prediction of the quality of the aquifer is dependent on the accurate mapping of both lithologic units and hydrogeologic parameters. In this project, the influence of petrophysical characteristics of the sedimentary rocks to the quality of the aquifer is investigated with a view to finding a correlation between these characteristics, the type and nature of sedimentary rocks present and their hydrogeologic properties. Investigation methods involved the use of geophysical wireline log data, lithological core logging, thin section microscopy and X-Ray Diffraction analysis. All this was done to characterize the sedimentary rocks in terms of composition, grain size and diagenesis. Porosity tests were also performed on the samples collected while permeability data was collected from the Department of Natural Resources and Mines (DNR & M), Australia. The basins of interest for this project are the Bowen Basin in Australia and the Kalahari Basin in Botswana. The two basins are similar, though structurally different. The basins are similar in the sense that they have got similarity in their rock sequence. All the work done on the Bowen Basin and the results obtained are extrapolated to the similar Kalahari Basin. The units of the Bowen Basin are underlain by the Late Carboniferous to Early Permian Camboon Volcanics. The Permian units include the Buffel, Barfield, Flat Top, and Gyranda Formations and the Baralaba Coal Measures. The Triassic units are the Rewan Group, Clematis Sandstone and Moolayember Formation. Within the Bowen Basin the Permian units are generally argillaceous and therefore have generally low porosities and permeabilities and also give low resistivity (RES) base lines and high gamma ray (GR) baselines. However where fractured, the units yield some water from the shale. Boreholes drawing water from the Barfield, Flat Top and Gyranda Formations tap the fractured shales. The Triassic aquifers present a different picture. The best aquifers with high porosities and permeabilities are of the Triassic age and their distribution is influenced by their proximity to the source area. Sedimentary rocks of the Triassic age in the Bowen Basin become more argillaceous at more distal positions from the source area. The Rewan Group in particular shows this trend and hence better aquifers within the Rewan are those close to the source area. The Kalahari Basin Karoo stratigraphy commences with the Late Carboniferous to Early Permian glaciogenic sedimentary rocks of the Dwyka Group. The Dwyka Group is overlain by the argillaceous Permian to Early Triassic sedimentary rocks of The Ecca Group and the Beaufort Group. Overlying the Beaufort Group is the Lebung Group (lower Mosolotsane Formation-dominantly mudstone and siltstone sequence and upper Ntane Sandstone Formation- aeolian sandstone). Basaltic lavas of the stormberg Lava Group cap the Karoo stratigraphy. Few groundwater studies in the Karoo of the Kalahari Basin have shown that the Ecca Group does not posses good aquifer characteristics because of its argillaceous nature. However, thin arenaceous interbeds within the Ecca Group have yielded some groundwater. Non-measurable quantities of groundwater have been recorded from boreholes sunk in the Beaufort Group. Few boreholes penetrating the Mosolotsane Formation yielded very little groundwater whereas Ntane Sandstone have yielded a fair amount of groundwater. Groundwater yield from the Stormberg Lava Group is related to the presence of fractures.

Sedimentary deposits are important aquifers in many parts of the world and in order to explore, develop and manage these aquifers, it is necessary to determine the relationship between the hydrogeologic properties and sedimentary facies (aquifer characterization). Within a sedimentary hydrogeologic system, the environment of deposition and the resulting distribution of grain sizes, texture, and facies associations within different individual aquifer bodies influence variations in hydraulic properties. Successful prediction of the quality of the aquifer is dependent on the accurate mapping of both lithologic units and hydrogeologic parameters. In this project, the influence of petrophysical characteristics of the sedimentary rocks to the quality of the aquifer is investigated with a view to finding a correlation between these characteristics, the type and nature of sedimentary rocks present and their hydrogeologic properties. Investigation methods involved the use of geophysical wireline log data, lithological core logging, thin section microscopy and X-Ray Diffraction analysis. All this was done to characterize the sedimentary rocks in terms of composition, grain size and diagenesis. Porosity tests were also performed on the samples collected while permeability data was collected from the Department of Natural Resources and Mines (DNR & M), Australia. The basins of interest for this project are the Bowen Basin in Australia and the Kalahari Basin in Botswana. The two basins are similar, though structurally different. The basins are similar in the sense that they have got similarity in their rock sequence. All the work done on the Bowen Basin and the results obtained are extrapolated to the similar Kalahari Basin. The units of the Bowen Basin are underlain by the Late Carboniferous to Early Permian Camboon Volcanics. The Permian units include the Buffel, Barfield, Flat Top, and Gyranda Formations and the Baralaba Coal Measures. The Triassic units are the Rewan Group, Clematis Sandstone and Moolayember Formation. Within the Bowen Basin the Permian units are generally argillaceous and therefore have generally low porosities and permeabilities and also give low resistivity (RES) base lines and high gamma ray (GR) baselines. However where fractured, the units yield some water from the shale. Boreholes drawing water from the Barfield, Flat Top and Gyranda Formations tap the fractured shales. The Triassic aquifers present a different picture. The best aquifers with high porosities and permeabilities are of the Triassic age and their distribution is influenced by their proximity to the source area. Sedimentary rocks of the Triassic age in the Bowen Basin become more argillaceous at more distal positions from the source area. The Rewan Group in particular shows this trend and hence better aquifers within the Rewan are those close to the source area. The Kalahari Basin Karoo stratigraphy commences with the Late Carboniferous to Early Permian glaciogenic sedimentary rocks of the Dwyka Group. The Dwyka Group is overlain by the argillaceous Permian to Early Triassic sedimentary rocks of The Ecca Group and the Beaufort Group. Overlying the Beaufort Group is the Lebung Group (lower Mosolotsane Formation-dominantly mudstone and siltstone sequence and upper Ntane Sandstone Formation- aeolian sandstone). Basaltic lavas of the stormberg Lava Group cap the Karoo stratigraphy. Few groundwater studies in the Karoo of the Kalahari Basin have shown that the Ecca Group does not posses good aquifer characteristics because of its argillaceous nature. However, thin arenaceous interbeds within the Ecca Group have yielded some groundwater. Non-measurable quantities of groundwater have been recorded from boreholes sunk in the Beaufort Group. Few boreholes penetrating the Mosolotsane Formation yielded very little groundwater whereas Ntane Sandstone have yielded a fair amount of groundwater. Groundwater yield from the Stormberg Lava Group is related to the presence of fractures.

Sedimentary deposits are important aquifers in many parts of the world and in order to explore, develop and manage these aquifers, it is necessary to determine the relationship between the hydrogeologic properties and sedimentary facies (aquifer characterization). Within a sedimentary hydrogeologic system, the environment of deposition and the resulting distribution of grain sizes, texture, and facies associations within different individual aquifer bodies influence variations in hydraulic properties. Successful prediction of the quality of the aquifer is dependent on the accurate mapping of both lithologic units and hydrogeologic parameters. In this project, the influence of petrophysical characteristics of the sedimentary rocks to the quality of the aquifer is investigated with a view to finding a correlation between these characteristics, the type and nature of sedimentary rocks present and their hydrogeologic properties. Investigation methods involved the use of geophysical wireline log data, lithological core logging, thin section microscopy and X-Ray Diffraction analysis. All this was done to characterize the sedimentary rocks in terms of composition, grain size and diagenesis. Porosity tests were also performed on the samples collected while permeability data was collected from the Department of Natural Resources and Mines (DNR & M), Australia. The basins of interest for this project are the Bowen Basin in Australia and the Kalahari Basin in Botswana. The two basins are similar, though structurally different. The basins are similar in the sense that they have got similarity in their rock sequence. All the work done on the Bowen Basin and the results obtained are extrapolated to the similar Kalahari Basin. The units of the Bowen Basin are underlain by the Late Carboniferous to Early Permian Camboon Volcanics. The Permian units include the Buffel, Barfield, Flat Top, and Gyranda Formations and the Baralaba Coal Measures. The Triassic units are the Rewan Group, Clematis Sandstone and Moolayember Formation. Within the Bowen Basin the Permian units are generally argillaceous and therefore have generally low porosities and permeabilities and also give low resistivity (RES) base lines and high gamma ray (GR) baselines. However where fractured, the units yield some water from the shale. Boreholes drawing water from the Barfield, Flat Top and Gyranda Formations tap the fractured shales. The Triassic aquifers present a different picture. The best aquifers with high porosities and permeabilities are of the Triassic age and their distribution is influenced by their proximity to the source area. Sedimentary rocks of the Triassic age in the Bowen Basin become more argillaceous at more distal positions from the source area. The Rewan Group in particular shows this trend and hence better aquifers within the Rewan are those close to the source area. The Kalahari Basin Karoo stratigraphy commences with the Late Carboniferous to Early Permian glaciogenic sedimentary rocks of the Dwyka Group. The Dwyka Group is overlain by the argillaceous Permian to Early Triassic sedimentary rocks of The Ecca Group and the Beaufort Group. Overlying the Beaufort Group is the Lebung Group (lower Mosolotsane Formation-dominantly mudstone and siltstone sequence and upper Ntane Sandstone Formation- aeolian sandstone). Basaltic lavas of the stormberg Lava Group cap the Karoo stratigraphy. Few groundwater studies in the Karoo of the Kalahari Basin have shown that the Ecca Group does not posses good aquifer characteristics because of its argillaceous nature. However, thin arenaceous interbeds within the Ecca Group have yielded some groundwater. Non-measurable quantities of groundwater have been recorded from boreholes sunk in the Beaufort Group. Few boreholes penetrating the Mosolotsane Formation yielded very little groundwater whereas Ntane Sandstone have yielded a fair amount of groundwater. Groundwater yield from the Stormberg Lava Group is related to the presence of fractures.

Groundwater levels in the Wheatbelt of Western Australia are rising and causing severe and widespread land salinisation. Evidence from northern Victoria showed that episodic recharge pulses following floods had caused significant groundwater rises. The aim of this study was to determine: 1. whether episodic recharge was significant compared to regular recharge in the Wheatbelt; 2. the conditions under which episodic recharge occurs. (For complete abstract open document)

The intermontane Mackenzie Basin is located within the central South Island of New Zealand. The glacial basin contains three glacial lakes which are used for hydroelectric power generation via a canal system that links the lakes. The basin is an area of climate extremes, low rainfall, high summer temperatures, and snowy winters. The area is predominantly used for pastoral farming, however farming practices are changing and, combined with an increasing population, there is a need to define the groundwater resources to enable sustainable resource management. Little is currently known about the hydrogeological system within the Mackenzie Basin, and what is known is from investigations carried out during the construction of the canal system from 1935 to 1985. There are four glacial formations that overlie Tertiary sequences and Torlesse bedrock. However, due to the glacial processes that have been ongoing over at least the last 300 ka, determining the occurrence and extent of groundwater within the outwash gravels is difficult. It is suggested that the permeability of the formations decreases with depth, therefore horizontal and vertical hydraulic conductivity decrease with depth. A shallow groundwater table is present within the Post Glacial Alluvial Gravels which is recharged directly from fast flowing streams and rivers as well as rainfall. It appears that this shallow system moves rapidly through the system and it is unlikely that the water infiltrates downwards to recharge the deeper groundwater system. It is thought that a deep groundwater system flows preferentially through the Mt John Outwash Gravels, being the second youngest glacial formation. Water chemistry and age dating tracer analysis indicate that the deeper groundwater is over 80 years old and that the groundwater system is recharging slowly. The shallow groundwater in the Post Glacial Alluvial Gravels and within the major fans to the east of the basin is 10 to 20 years in age. Baseline data such as water chemistry, groundwater levels, and surface water gaugings have been collected which can be used for future investigations. More data needs to be collected to create a long term record to further define the hydrogeological system and to determine the best way to manage the resource for long term sustainable use in the future.

Doctor of Philosophy / Water quality guidelines (WQGs) present concentrations of contaminants that are designed to be protective of aquatic ecosystems. In Australia, guidance for assessment of water quality is provided by the ANZECC and ARMCANZ (2000) Guidelines for Fresh and Marine Water Quality. WQGs are generally provided for individual contaminants, not complex mixtures of chemicals, where interaction between contaminants may occur. Complex mixtures of contaminants are however, more commonly found in the environment than singular chemicals. The likelihood and consequences of adverse effects occurring in aquatic ecosystems resulting from contaminants are generally assessed using an ecological risk assessment (ERA) framework. Ecological risk assessment is often a tiered approach, whereby risks identified in early stages, using conservative assumptions, prompt further detailed and more realistic assessment in higher tiers. The objectives of this study were: to assess and investigate the toxicity of the mixture of volatile chlorinated hydrocarbons (VCHs) in groundwater to indigenous marine organisms; to present a ‘best practice’ ecological risk assessment of the discharge of contaminated groundwater to an estuarine embayment and to develop techniques to quantify the environmental risk; and to evaluate the existing ANZECC and ARMCANZ (2000) WQGs for VCHs and to derive new WQGs, where appropriate. Previous investigations at a chemical manufacturing facility in Botany, Sydney, identified several plumes of groundwater contamination with VCHs. Contaminated groundwater containing a complex mixture of VCHs was identified as discharging, via a series of stormwater drains, to surface water in nearby Penrhyn Estuary, an adjacent small intertidal embayment on the northern margin of Botany Bay. A screening level ecological hazard assessment was undertaken using the hazard quotient (HQ) approach, whereby contaminant concentrations measured in the environment were screened against published trigger values (TVs) presented in ANZECC and ARMCANZ (2000). Existing TVs were available for 9 of the 14 VCHs present in surface water in the estuary and new TVs were derived for the remaining 5 VCHs. A greater hazard was identified in the estuary at low tide than high tide or when VCH concentrations from both high and low tides were assessed together. A greater hazard was also identified in the estuary when the toxicity of the mixture was assessed, rather than the toxicity of individual contaminants. The screening level hazard assessment also identified several limitations, including: the low reliability of the TVs for VCHs provided in ANZECC and ARMCANZ (2000); the limited applicability of the TVs to a complex mixture of 14 potentially interacting contaminants; the use of deterministic measures for each of the exposure and toxicity profiles in the HQ method and the associated lack of elements of probability to assess ‘risk’. Subsequent studies were undertaken to address these identified shortcomings of the screening level hazard assessment as described in the following chapters. A toxicity testing methodology was adapted and evaluated for suitability in preventing loss of VCHs from test solutions and also for testing with 6 indigenous marine organisms, including: oyster (Saccostrea commercialis) and sea urchin larvae (Heliocidaris tuberculata); a benthic alga (Nitzschia closterium); an amphipod (Allorchestes compressa); a larval fish (Macquaria novemaculeata); and a polychaete worm (Diopatra dentata). The study evaluated possible VCH loss from 44 mL vials for small organisms (H.tuberculata, S.commercialis and N.closterium) and 1 L jars for larger organisms (M.novemaculeata, A.compressa and D.dentata). Vials were effective in preventing loss of VCHs, however, an average 46% of VCHs were lost from jars, attributable to the headspace provided in the vessels. Test jars were deemed suitable for use with the organisms as test conditions, i.e. dissolved oxygen content and pH, were maintained, however, variability in test organism survival was identified, with some control tests failing to meet all acceptance criteria. Direct toxicity assessment (DTA) of groundwater contaminated with VCHs was undertaken using 5 indigenous marine organisms and site-specific species sensitivity distributions (SSDs) and TVs were derived for the complex mixture of VCHs for application to surface water in Penrhyn Estuary. Test organisms included A.compressa, H.tuberculata, S.commercialis, D.dentata and N.closterium. The SSD was derived using NOEC data in accordance with procedures presented in ANZECC and ARMCANZ (2000) for deriving WQGs. The site-specific SSD adopted was a log-normal distribution, using an acute to chronic ratio (ACR) of 5, with a 95% TV of 838 μg/L total VCHs. A number of additional scenarios were undertaken to evaluate the effect of including different ACRs (i.e. 5 or 10), inclusion of larval development tests as either acute or chronic tests and choice of SSD distribution (i.e. log-normal, Burr Type III and Pareto). TVs for the scenarios modelled varied from 67 μg/L to 954 μg/L total VCHs. A site-specific, quantitative ERA was undertaken of the surface water contaminated with VCHs in Penrhyn Estuary. The risk assessment included probabilistic elements for toxicity (i.e. the site-specific SSD) and exposure (i.e. a cumulative distribution function of monitoring data for VCHs in surface waters in the estuary). The joint probability curve (JPC) methodology was used to derive quantitative estimates of ecological risk (δ) and the type of exposure in the source areas in surface water drains entering the estuary, i.e. Springvale and Floodvale Drains, Springvale and Floodvale Tributaries and the Inner and Outer Estuary. The risk of possible adverse effects and likely adverse effects were each assessed using SSDs derived from NOEC and EC50 data, respectively. Estimates of risk (δ) of possible adverse effects (i.e. based on NOEC data) varied from a maximum of 85% in the Springvale Drain source area to <1% in the outer estuary and estimates of likely adverse effects (i.e. based on EC50 data) varied from 78% to 0%. The ERA represents a ‘best practice’ ecological risk assessment of contamination of an estuary using site-specific probabilistic elements for toxicity and exposure assessments. The VCHs identified in surface water in Penrhyn Estuary are additive in toxicity and act under the narcotic pathway, inhibiting cellular processes through interference with membrane integrity. Lethal toxicity to 50% of organisms (i.e. LC50) is typically reported at the internal lethal concentration (ILC) or critical body residue (CBR) of ~2.5 mmol/kg wet weight or within the range of 1 to 10 mmol/kg wet weight. To evaluate the sensitivity of the test organisms to VCHs and to determine if toxicity in the DTA was due to VCHs, the internal residue for 6 test organisms was calculated for the mixture of VCHs in groundwater and toxicity testing with seawater spiked individually 2 VCHs, chloroform and 1,2-dichloroethane. Calculated residues (at LC50/EC50) were typically between 1 and 10 mmol/kg, with the exception of the algal and sea urchin toxicity tests, which were considerably lower than the expected minimum. Mean internal residues for the groundwater, chloroform and 1,2-dichloroethane were 0.88 mmol/kg, 2.84 mmol/kg and 2.32 mmol/kg, respectively, i.e. close to the predicted value of ~2.5 mmol/kg, indicating that the organisms were suitably sensitive to VCHs. There was no significant difference (P>0.05) between the mean residues of each of the three treatments and the study concluded that the additive toxicity of the VCHs in groundwater was sufficient to account for the observed toxicity (i.e. VCHs caused the toxicity in the DTA undertaken). Evaluation of the existing low reliability ANZECC and ARMCANZ (2000) TVs for chloroform and 1,2-dichloroethane was undertaken to determine if these guidelines were protective of indigenous marine organisms. NOECs, derived from toxicity testing of 1,2- dichloroethane and chloroform with 6 indigenous marine organisms, were screened against the existing low reliability TVs. The TVs for 1,2-dichloroethane and chloroform were protective of 4 of the 6 species tested (A.compressa, D.dentata, S.commercialis and M.novemaculeata), however, the TVs were not protective of the alga (N.closterium) or the sea urchin larvae (H.tuberculata). As the existing TVs were not considered to be adequately protective, SSDs were derived using the NOEC data generated from the testing in accordance with procedures outlined in ANZECC and ARMCANZ (2000). Moderate reliability TVs of 3 μg/L and 165 μg/L were derived for chloroform and 1,2- dichloroethane, respectively, i.e. considerably lower than the existing TVs of 770 μg/L and 1900 μg/L. Differences between the existing and newly derived TVs were considered to result from the sensitive endpoints selected (i.e. growth and larval development rather than survival) and from variability inherent when deriving SSDs using a small number of test species. Ongoing groundwater monitoring indicated that the plumes of VCHs in groundwater, identified in the 1990s, were continuing to migrate towards Botany Bay. Discharge of these groundwater plumes into Botany Bay would result in significant increases in the concentrations of VCHs in the receiving environment and would likely lead to significant environmental impacts. In 2006, a groundwater remediation system was commissioned to prevent the discharge of groundwater containing VCHs into Penrhyn Estuary and Botany Bay. The success of the project had only been measured according to chemical and engineering objectives. Assessment of changes in ecological risk is vital to the success of ERA and central to the ERA management framework. Whereas monitoring of chemical concentrations provides qualitative information that risk should decrease, it cannot quantify the reduction in ecological risk. To assess the ecological risk following implementation of the groundwater treatment system, the risk assessment was revised using surface water monitoring data collected during 2007 and 2008. The ERA indicated that, following remediation of the groundwater, ecological risk in Penrhyn Estuary reduced from a maximum of 35% prior to remediation, to a maximum of only 1.3% after remediation. Using the same methodology applied in the initial risk assessment, the success of the groundwater remediation was measured in terms of ecological risk, rather than engineering or chemical measures of success. Prior to the present investigation, existing techniques for assessing ecological risk of VCH contamination in aquatic ecosystems were inadequate to characterise ecological risk. The current study demonstrated that through monitoring of surface water at the site and DTA using indigenous marine organisms, ecological risk can be assessed using site-specific, quantitative techniques for a complex mixture of VCHs in groundwater. The present investigation also identified that existing ANZECC and ARMCANZ (2000) low reliability TVs were less protective of indigenous test organisms than previously thought and therefore, new TVs were derived in the current work. The present study showed that revision of the risk assessment as conditions change is crucial to the success of the ecological risk management framework.

Sedimentary deposits are important aquifers in many parts of the world and in order to explore, develop and manage these aquifers, it is necessary to determine the relationship between the hydrogeologic properties and sedimentary facies (aquifer characterization). Within a sedimentary hydrogeologic system, the environment of deposition and the resulting distribution of grain sizes, texture, and facies associations within different individual aquifer bodies influence variations in hydraulic properties. Successful prediction of the quality of the aquifer is dependent on the accurate mapping of both lithologic units and hydrogeologic parameters. In this project, the influence of petrophysical characteristics of the sedimentary rocks to the quality of the aquifer is investigated with a view to finding a correlation between these characteristics, the type and nature of sedimentary rocks present and their hydrogeologic properties. Investigation methods involved the use of geophysical wireline log data, lithological core logging, thin section microscopy and X-Ray Diffraction analysis. All this was done to characterize the sedimentary rocks in terms of composition, grain size and diagenesis. Porosity tests were also performed on the samples collected while permeability data was collected from the Department of Natural Resources and Mines (DNR & M), Australia. The basins of interest for this project are the Bowen Basin in Australia and the Kalahari Basin in Botswana. The two basins are similar, though structurally different. The basins are similar in the sense that they have got similarity in their rock sequence. All the work done on the Bowen Basin and the results obtained are extrapolated to the similar Kalahari Basin. The units of the Bowen Basin are underlain by the Late Carboniferous to Early Permian Camboon Volcanics. The Permian units include the Buffel, Barfield, Flat Top, and Gyranda Formations and the Baralaba Coal Measures. The Triassic units are the Rewan Group, Clematis Sandstone and Moolayember Formation. Within the Bowen Basin the Permian units are generally argillaceous and therefore have generally low porosities and permeabilities and also give low resistivity (RES) base lines and high gamma ray (GR) baselines. However where fractured, the units yield some water from the shale. Boreholes drawing water from the Barfield, Flat Top and Gyranda Formations tap the fractured shales. The Triassic aquifers present a different picture. The best aquifers with high porosities and permeabilities are of the Triassic age and their distribution is influenced by their proximity to the source area. Sedimentary rocks of the Triassic age in the Bowen Basin become more argillaceous at more distal positions from the source area. The Rewan Group in particular shows this trend and hence better aquifers within the Rewan are those close to the source area. The Kalahari Basin Karoo stratigraphy commences with the Late Carboniferous to Early Permian glaciogenic sedimentary rocks of the Dwyka Group. The Dwyka Group is overlain by the argillaceous Permian to Early Triassic sedimentary rocks of The Ecca Group and the Beaufort Group. Overlying the Beaufort Group is the Lebung Group (lower Mosolotsane Formation-dominantly mudstone and siltstone sequence and upper Ntane Sandstone Formation- aeolian sandstone). Basaltic lavas of the stormberg Lava Group cap the Karoo stratigraphy. Few groundwater studies in the Karoo of the Kalahari Basin have shown that the Ecca Group does not posses good aquifer characteristics because of its argillaceous nature. However, thin arenaceous interbeds within the Ecca Group have yielded some groundwater. Non-measurable quantities of groundwater have been recorded from boreholes sunk in the Beaufort Group. Few boreholes penetrating the Mosolotsane Formation yielded very little groundwater whereas Ntane Sandstone have yielded a fair amount of groundwater. Groundwater yield from the Stormberg Lava Group is related to the presence of fractures.

[Truncated abstract] It has become widely apparent throughout the world that the discharge of nitrogen contaminated groundwater is reducing surface water quality of marine coastal waters, and is subsequently contributing to the decline of benthic habitats such as seagrasses. A process-based understanding of submarine groundwater discharge (SGD) has lagged behind these impacts, and this lack of understanding is addressed by this thesis. This thesis, of the spatial and temporal complexity of SGD, has uncovered and answered questions regarding the sources, fate and transport of SGD in a complex coastal discharge environment. Radium isotope techniques, groundwater biogeochemical investigations and HAMSOM surface water modelling have identified the magnitude, transport and fate of SGD in Cockburn Sound, a semienclosed embayment in Western Australia. A temporal periodicity that encompassed end-of-winter, early-summer, late-summer and mid-winter regimes of hydrology and oceanography, was employed in field studies that spanned the years 2003, 2004 and 2005. ... The fate of the groundwater in the semi-enclosed embayment was investigated using knowledge of surface water currents. Localised regions of high groundwater influence were identified in the surface waters of the embayment, and through the application of a 3-dimensional hydrodynamic model (HAMSOM) it was discovered that, despite similar total volume residence times, variation in the surface flow regime resulted in very different fates for groundwater discharged to the embayment. For three of the four investigated seasonal regimes, groundwater discharged at the shoreline was shown to be rapidly exported out of the embayment (within approximately 1-3 days). During mid-winter very different wind and current regimes existed, resulting in the lateral transport of shoreline groundwater across the embayment, presenting potential for nutrient recirculation within the system for longer time periods (10+ days). Lateral transport of groundwater during mid-winter from the limestone region of the coastline, may contribute to peaks in phytoplankton biomass that have been reported to occur at this time. The investigations into spatial, temporal and biogeochemical dynamics of SGD provided for further dissertation of the processes that affect these dynamics, at a scale that was relevant to marine embayments, coastal aquifers and the coastal ecosystem. It is hoped that this thesis will contribute to a better understanding of the inputs, dynamics and impacts of SGD on coastal ecosystems and lead to improved management strategies for coastal zones.